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Journal articles on the topic 'Microorganisme'
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Supianor, Supianor, Juanda Juanda, and Hardiono Hardiono. "Perbandingan Penambahan Bioaktivator EM-4 (Effective Microorganisme) Dan Mol (Microorganisme Local) Kulit Nanas (Anana Comosus L.Merr) Terhadap Waktu Terjadinya Kompos." JURNAL KESEHATAN LINGKUNGAN: Jurnal dan Aplikasi Teknik Kesehatan Lingkungan 15, no. 1 (2018): 567. http://dx.doi.org/10.31964/jkl.v15i1.41.
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The Comparison Of Additional Bio-Activator EM-4 (Effective Microorganism) And Mol (Microorganisme Local) Pineapple (Ananas Comosus L.Merr) Skin To The Composting Time. Composting is the reform process (decomposition) and stabilization of organic materials by microorganism in controlled environment (controlled) and its final outcome of humus or compost. It can be speed up by addition other ingredients called the activator. Activator is material consisting of enzymes and microorganisms (bacterial culture) that can accelerate the composting process. This study aimed to determine the effect of additional bioactivator EM-4 (Effective Microorganism) and MOL (Microorganism Local) pineapple skin (Ananas comosus l.merr) skin to the composting time. They was administered on each treatment and observed for 24 day. The result of the compost with the addition bio-activator EM-4 took for 16 days and compost with the addition MOL pineapple skin took for 14 days. Based on the statistical analysis by One Way Analysis of Variance method with α = 0.05 was significant effect between the addition of bio-activator EM-4 and MOL pineapple skin to the compositing time with average composting time for 16 and 14 days. Further study can be conducted by potential materials as basic raw materials for MOL such as fruits (banana, sugar cane, jackfruit), animal and human urine, and food scraps.
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Hafiz, Muhammad, Surya Aji Wibowo, Wahyu Purbaningsih, and Sriyono Sriyono. "Penyuluhan Pembuatan Microorganisme Local Bagi Warga Desa Brengkol Guna Mengurangi Penggunaan Pupuk Kimia Pada Pertanian." Surya Abdimas 2, no. 2 (2018): 21–26. http://dx.doi.org/10.37729/abdimas.v2i2.557.
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Mayoritas pertanian saat ini menggunakan pupuk kimia. Meskipun efektif dalam menyuburkan tanaman, namun dampak jangka panjangnya dapat merusak ekosistem persawahan dan lahan pertanian itu sendiri. Penyubur tanaman memanfaatkan mikro bioorganisme lokal menjadi solusi bagi petani lokal, menuju pertanian ramah lingkungan dan bebas dari pupuk dan obat-obatan kimiawi. Tujuan kegiatan ini adalah (1) Memanfaatkan limbah organik sebagai bahan pembuatan microorganisme local, (2) Menghindari penggunaan pupuk kimia agar hasil tanaman layak dikonsumsi, (3) Menginformasikan pemanfaatn limbah organik sebagai bahan microorganisme local terhadap petani. Kegiatan ini dilaksanakan pada tanggal 30 Januari 2017, bertempat di aula balai desa Brengkol, kecamatan Pituruh, pukul 08.00 WIB. Metode pelaksanaan yaitu penyuluhan, mengintroduksikan bahan limbah organik dan pembuatan micoorganisme local. Hasil kegiatan pembuatan microorganisme local di desa Brengkol kecamatan Pituruh menunjukan: (1) Kegiatan ini dihadiri oleh perangkat desa, petani, karang taruna dan tohoh masyarakat, (2) Peserta yang mengikuti kegiatan ini antusias dan sangat termotivasi dengan penyampaian materi dan praktik sehingga dengan penyampaian materi dan praktik pembuatan MOL peserta diharapkan bisa mempraktekan sendiri.
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Supriwan, Supriwan, A. E. Harahap, and E. Erwan. "Hasil Fermentasi Menggunakan Effective Microorganisme-4 dengan Penyimpanan Berbeda." Jurnal Ilmu dan Industri Peternakan (Journal of Animal Husbandry Science and Industry) 6, no. 2 (2020): 77. http://dx.doi.org/10.24252/jiip.v6i2.18313.
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Tujuan untuk mengetahui kualitas nutrisi pellet yang disimpan dengan bahan kulit ari biji kedelai yang difermentasi menggunakan EM4. Metode yang digunakan dalam penelitian ini adalah Rancangan Acak Lengkap (RAL) dengan 5 perlakuan dan 5 ulangan. Peubah yang diamati adalah kualitas nutrisi pellet meliputi (kadar air, protein kasar, lemak kasar, serat kasar, abu dan bahan ekstrak tanpa nitrogen). Penelitian ini dilaksanakan di Laboratorium Ilmu Nurisi dan Kimia Fakultas Pertanian dan Peternakan Universitas Islam Negeri Sultan Syarif Kasim Riau dan Laboratorium Hasil Perikanan Universitas Riau. Hasil penelitian ini adalah semakin lama waktu simpan dapat mempertahankan kualitas nutrisi dilihat dari protein kasar, lemak kasar dan BETN dan tidak berpengaruh nyata (P>0.05) terhadap kadar air, serat kasar, dan abu yang dihasilkan. Kesimpulan dari penelitian ini menunjukkan bahwa lama penyimpanan 8 minggu merupakan perlakuan terbaik dalam meningkatkan kualitas nutrisi pellet dilihat dari kandungan protein kasar sebesar 20,70%.
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Benaroyo, Lazare. "Les recherches de Theodor Kocher sur l'étiologie de l'ostéomyélite et de la strumite aiguës." Gesnerus 49, no. 2 (1992): 151–60. http://dx.doi.org/10.1163/22977953-04902004.
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Theodor Kocher démontre expérimentalement en 1879 que ¡’ostéomyélite aiguë est une maladie infectieuse causée par un microorganisme non spécifique, le microcoque. Il montre que Vinfection de la moelle osseuse est consécutive à une dissémination hêmatogène d’une infection locale, cutanée ou muqueuse. La forme clinique et pathologique que prend la maladie dépend, selon lui, non seulement de la virulence du microcoque, mais également de la qualité du terrain sur lequel ce dernier se développe. Il suggère la même année que la strumite aiguë (l’inflammation du goitre) a, par analogie, la même étiologie que l’ostéomyélite ; il ne fournit cependant pas de preuves expérimentales à l’appui de cette hypothèse. Nous pouvons ainsi constater qu’à l’aube des années 1880, Kocher a défini de manière originale l’infection comme le produit d’une interaction entre un microorganisme et son hôte. L’influence exercée par ses idées sur ses contemporains atteste qu’il a stimulé les recherches sur l’étiologie des maladies infectieuses.
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Meriatna, Meriatna, Suryati Suryati, and Aulia Fahri. "Pengaruh Waktu Fermentasi dan Volume Bio Aktivator EM4 (Effective Microorganisme) pada Pembuatan Pupuk Organik Cair (POC) dari Limbah Buah-Buahan." Jurnal Teknologi Kimia Unimal 7, no. 1 (2019): 13. http://dx.doi.org/10.29103/jtku.v7i1.1172.
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Pembuatan pupuk organik cair khususnya dari limbah buah-buahan dengan penambahan bio aktivator EM4 (Effective Microorganisme) bertujuan untuk menentukan pengaruh waktu pembuatan terhadap kandungan Nitrogen (N), Phosfor (P2O5), dan Kalium (K2O) dalam pupuk organik cair, serta menentukan pengaruh bio aktivator EM4 terhadap kandungan N, P, K. Metode pembuatan pupuk organik cair ini yaitu limbah buah-buahan seperti buah semangka, jeruk, dan buah pepaya yang banyak mengandung air dihancurkan sebelum di fermentasikan. Kemudian bio aktivator EM4 disiapkan untuk penambahan dalam limbah buah-buahan yang sudah dikecilkan ukurannya. Limbah buah-buahan dimasukkan ke dalam galon air 5 liter, larutan bio aktivator EM4 kemudian dimasukkan ke dalam galon secara merata. Pengambilan sampel dilakukan berdasarkan variasi waktu 10 hari, 13 hari dan 16 hari serta variasi penambahan jumlah bio aktivator EM4 sebanyak 40 ml, 50 ml, dan 60 ml. Hasil penelitian menunjukkan bahwa kadar N, P, K terbaik didapat pada hari ke 13 dengan volume bio aktivator EM4 60 ml, untuk kandungan nitrogen yaitu 13,4 %, untuk kandungan phosfor 10,92 %, dan untuk kandungan kalium yaitu 6,39 %. Volume bio aktivator EM4 sangat berpengaruh terhadap kandungan N, P, dan K, dikarenakan semakin banyak volume bio aktivator EM4 maka kadar N, P, dan K juga akan semakin tinggi.Kata kunci:effective microorganisme, nitrogen, phosfor, kalium, pupuk organik cairPembuatan pupuk organik cair khususnya dari limbah buah-buahan dengan penambahan bio aktivator EM4 (Effective Microorganisme) bertujuan untuk menentukan pengaruh waktu pembuatan terhadap kandungan Nitrogen (N), Phosfor (P2O5), dan Kalium (K2O) dalam pupuk organik cair, serta menentukan pengaruh bio aktivator EM4 terhadap kandungan N, P, K. Metode pembuatan pupuk organik cair ini yaitu limbah buah-buahan seperti buah semangka, jeruk, dan buah pepaya yang banyak mengandung air dihancurkan sebelum di fermentasikan. Kemudian bio aktivator EM4 disiapkan untuk penambahan dalam limbah buah-buahan yang sudah dikecilkan ukurannya. Limbah buah-buahan dimasukkan ke dalam galon air 5 liter, larutan bio aktivator EM4 kemudian dimasukkan ke dalam galon secara merata. Pengambilan sampel dilakukan berdasarkan variasi waktu 10 hari, 13 hari dan 16 hari serta variasi penambahan jumlah bio aktivator EM4 sebanyak 40 ml, 50 ml, dan 60 ml. Hasil penelitian menunjukkan bahwa kadar N, P, K terbaik didapat pada hari ke 13 dengan volume bio aktivator EM4 60 ml, untuk kandungan nitrogen yaitu 13,4 %, untuk kandungan phosfor 10,92 %, dan untuk kandungan kalium yaitu 6,39 %. Volume bio aktivator EM4 sangat berpengaruh terhadap kandungan N, P, dan K, dikarenakan semakin banyak volume bio aktivator EM4 maka kadar N, P, dan K juga akan semakin tinggi.
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Fridarti, Fridarti, N. Jamarun, M. Zain, and R. W. S. Ningrat. "The Characteristics of Rumen Fluid and Digestibility Cocoa Leaves Fermentation With Microorganisme Indigenus Method In -Vitro." International Journal of Forest, Animal and Fisheries Research 1, no. 4 (2017): 1–7. http://dx.doi.org/10.22161/ijfaf.1.4.1.
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Adrianto, Mario Dwi. "Analisis Produksi Biogas Berdasarkan Bahan Baku Limbah Kotoran Sapi, Serbuk Gergaji, dan Effective Microorganisme-4 (EM4)." Jurnal BETA (Biosistem dan Teknik Pertanian) 7, no. 2 (2019): 297. http://dx.doi.org/10.24843/jbeta.2019.v07.i02.p10.
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Biogas is an alternative energy made from organic waste. Organic waste which is often used as raw material for biogas is cow dung. Cow manure is used as raw material for biogas because the cellulose content in it is quite high and its availability is relatively large. However, if only one material is used, the optimum C / N ratio will not be achieved. If the optimum C / N ratio is achieved, the gas produced in biogas production will also increase. One way to get the optimum C / N ratio is by adding biogas filling material. In this study, variations in the composition of biogas filling materials were carried out, namely (1) cow dung, (2) cow dung and sawdust, and (3) cow dung, sawdust, and EM4. Of the three variations of this filling material, measurements of temperature, gas pressure, and pH will be carried out. The purpose of this study was to determine the effect of the composition of the biogas mixture on the variables of temperature, gas pressure, and pH. The biogas production process were divided into several stages, such as mixing filling material, inputting filling material into the digester, fermentation process, taking the data of observation, and analyzing the data. The results showed that differences in the composition of biogas raw materials affected the variable temperature and gas pressure. As for pH, the composition of the filling material does not have a significant effect.
Keywords: biogas, cow dung, sawdust, EM4
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Khazanah, Wiqayatun, Nurliana Nurliana, and Rini Safitri. "The Effect of Irradiation to Sensoric Characteristic, Physic and Microbe in Sie Balu, Acehnese Dried Meat." International Journal of Tropical Veterinary and Biomedical Research 2, no. 1 (2017): 12–17. http://dx.doi.org/10.21157/ijtvbr.v2i1.8635.
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One of the Acehnese traditional food preserved by the addition of salt, acid and dried was sie balu. The preservation method may lead to changes in the structure and nutritional content. Sie balu with the addition of vinegar, garlic and ginger can reduce the value of water activity (aW), pH and bacterial counts. This condition affects the physical properties and sensory of sie balu. Irradiation can control pathogenic microorganisms in meat without affecting the physical condition. Low-dose irradiation is able to maintain the desired sensory attributes nutritious food products. This study aims to determine the characteristics of the sensory and physic sie baluthat irradiated with increasing doses and the shelf life of 3-6 weeks. Sie balu was made of 10 kg fresh beef, dried in the sun to dry, vacuum and irradiated at doses of 5, 7 and 9 kGy. Sensory test conducted by taste sie balu by trained panelists and fill out the hedonicform. The physical properties based on pH and aW. The microbe total calculated used Total Plate Count.The results showed that the irradiation dose significantly (P <0.05) affected on microbe total, aroma, color, texture and taste of sie balu. Storage time does not affect the sensory properties. Irradiation dose and storage time significantly (P <0.05) on pH and aWsiebalu. The study concluded that irradiation can improve the physical properties, sensory and microorganisme reductionof sie balu.
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Widyastuti, Sri, and Yogi Suyantara. "PENAMBAH AN SAM PAH SAYURAN PADA FERMENTASI BIOGAS DARI KOTORAN SAPI DENGAN STARTER EM4." WAKTU: Jurnal Teknik UNIPA 15, no. 1 (2017): 36–42. http://dx.doi.org/10.36456/waktu.v15i1.433.
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Jumlah sampah sayuran yang dihasilkan dari kegiatan pasar sangat melimpah, sampah sayuran dimanfaatkan sebagai bahan pembuatan pupuk kompos, selain digunakan sebagai bahan baku pupuk sampah sayuran dapat juga dimanfaatkan menjadi biogas. Tujuan dari penelitian ini untuk mengetahui pengaruh penambahan komposisi sampah sayuran pada fermentasi biogas dari kotoran sapi. Reaktor berupa digester drum kapasitas 150 liter sampah sayuran dicampur dengan kotoran sapi dan ditambah Effektive Microorganisme (EM4). Proses fermentasi selama 20 hari. Penelitian ini menggunakan 3 variasi berat sampah sayuran yaitu berat sampah sayuran 10 kg, 14 kg, dan 18 kg. Hasil penelitian menunjukkan dengan semakin banyaknya takaran sampah sayuran maka tekanan gas yang dihasilkan semakin besar, tetapi berbanding terbalik dengan uji nyala api. Nilai uji tekanan gas dan uji lama nyala api pada sampel P1,P2, dan P3 berturut-turut 27,73 cm., 78 detik, 20,67 cm., 38,06 detik, dan 27,83 cm., 23,23 detik.
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Anis, Mohhamad Yunus, and Dyah Hariani. "Pemberian EM4 (Effective Microorganisme 4) Hasil Kultur dalam Media yang Berbeda pada Pakan untuk Budi daya Lele (Clarias sp.)." Jurnal Riset Biologi dan Aplikasinya 1, no. 1 (2019): 1. http://dx.doi.org/10.26740/jrba.v1n1.p1-8.
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Ikan lele (Clarias sp.) merupakan salah satu komoditas perikanan air tawar yang banyak diminati di Indonesia dan terjadi peningkatan produksinya setiap tahun. Untuk itu, terus dipacu peningkatan produksi ikan lele. Upaya yang dilakukan untuk meningkatkan produksi ikan lele yaitu melalui pemberian EM4 (Effective microorganism 4) pada pakan. EM4 yang digunakan berisi Lactobacillus casei dan Saccharomyces cerevisiae. EM4 dikultur dalam media yang dibuat dari molase, bekatul, susu sapi, buah nanas, kunyit putih, temulawak, jahe merah dan air kelapa. EM4 hasil kultur dalam media disebut sebagai fermentor. Penelitian ini bertujuan untuk menguji pengaruh pemberian EM4 hasil kultur dalam media yang berbeda pada pakan terhadap laju pertumbuhan spesifik/spesific growth rate (SGR), rasio konversi pakan/feed conversion ratio (FCR) dan tingkat kelangsungan hidup/survival rate (SR) benih ikan lele. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL). Perlakuan terdiri atas A (pakan komersial), B (pakan+10% EM4), C (pakan+10% fermentor 1), D (pakan+10% fermentor 2) dan E (pakan+10% fermentor 3), setiap perlakuan diulang sebanyak empat kali. Pakan difermentasi selama 1-3 hari sebelum pakan diberikan kepada benih ikan lele ukuran panjang 7-9 cm. Data dianalisis menggunakan ANAVA. Hasil penelitian menunjukkan bahwa pemberian EM4 hasil kultur dalam media yang berbeda pada pakan berpengaruh secara signifikan terhadap SGR, FCR dan SR benih ikan lele (P<0,05). Perlakuan terbaik diperoleh pada perlakuan E (pakan+10% fermentor 3) dengan nilai SGR sebesar 5,91±0,04%, FCR sebesar 0,88±0,045 dan SR sebesar 73,50±1,91%.
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Bach, Stéphane, Pierre Colas, and Marc Blondel. "La levure modèle et outil… aussi pour la recherche thérapeutique." médecine/sciences 36, no. 5 (2020): 504–14. http://dx.doi.org/10.1051/medsci/2020077.
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La levure a été utilisée de façon empirique pendant des millénaires pour la panification et la fermentation des sucres en alcool. C’est seulement à partir de 1857 que Louis Pasteur décrit le microorganisme à l’origine de ces deux activités agroalimentaires majeures. Dès lors, les souches de levure ont pu être sélectionnées et modifiées sur une base rationnelle pour optimiser leurs usages agroalimentaires, permettant ainsi l’essor de la levure comme modèle biologique eucaryote. Cette utilisation a conduit à de très nombreuses découvertes de biologie cellulaire fondamentale. Depuis une vingtaine d’années, la levure est également utilisée comme modèle et outil pour la santé humaine. Ces approches s’étendent de la production de molécules thérapeutiques à la recherche de candidats-médicaments et de sondes chimiques, en passant par la mise au point de tests diagnostiques et la découverte de nouvelles cibles thérapeutiques. Cette utilisation de la levure en chémobiologie fait l’objet de la présente revue.
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Sutrisno, Joko. "PEMBUATAN BIOGAS DARI BAHAN SAMPAH SAYURAN (KUBIS, KANGKUNG dan BAYAM)." WAKTU: Jurnal Teknik UNIPA 8, no. 1 (2010): 100–112. http://dx.doi.org/10.36456/waktu.v8i1.885.
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Sampah sayur di pasar-pasar tradisional sangat berlimpah jumlahnya, terdiri dari beberapa bahanbuangan sisa proses penyortiran untuk dijual seperti sayur kangkung,. Kubis, bayam, sawi, daunubi jalar,daun ubi kayu, kacang panjang dan brokoli. Sesungguhnya semua sisa sayur yangakhirnya menjadi sampah ini dapat dimanfaatkan untuk dijadikan bahan guna diproses agarmenghasilkan gas bio yang merupakan energi panas alternative dengan bahan baku dapatdiperbarui. Melalui alat digester biogas yang disiapkan pada ukuran kecil untuk skala rumahtangga, kebutuhan energi panas untuk keperluan memasak dapat dipenuhi dari proses ini.Penelitian ini merupakan percobaan pembuatan gas bio dengan bahan sampah sayur basah daripasar tradisional berupa 3 variasi bahan yaitu kangkung, bayam dan kubis, yang dihaluskanterlebih dahulu dengan mesin perajang sampah. Untuk mempercepat proses digunakan starterberupa bakteri Effektive Microorganisme (EM4) yang banyak beredar di pasaran. Hasil percobaanmenunjukan bahwa ketiga bahan sayuran tersebut dapat dijadikan bahan pembuatan gas bio,dengan tekanan produk maksimal yang tidak signifikan perbedaannya.
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Pedraza, Raúl O., Kátia R. S. Teixeira, Ana Fernández Scavino, et al. "Microorganismos que mejoran el crecimiento de las plantas y la calidad de los suelos. Revisión." Corpoica Ciencia y Tecnología Agropecuaria 11, no. 2 (2010): 155. http://dx.doi.org/10.21930/rcta.vol11_num2_art:206.
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<p>El presente artículo surge de la revisión de la teoría y temas prácticos desarrollados durante el curso”Caracterización y contribución de las plantas que promueven el crecimiento de microorganismos en la sostenibilidad de la agricultura”, llevado a cabo en el Laboratorio de Microbiología de Suelos de la Corporación Colombiana de Investigación Agropecuaria (Corpoica), ubicado en Mosquera (Cundinamarca), Colombia, en julio de 2010. Esta actividad fue desarrollada en el marco de la Red Dimiagri que incluye a investigadores de Argentina, Brasil, Colombia, España, Guatemala, México y Uruguay, reunidos en una acción de coordinación financiada por el Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo (Cyted). Los aspectos inherentes al crecimiento y la sanidad vegetal, el sistema radical, el suelo circundante (rizósfera), los microorganismos asociados en ese sistema y su contribución al manejo sustentable del complejo suelo-planta fueron analizados en este trabajo. También se abordan temas como la biodiversidad microbiana y su efecto en la calidad del suelo; el ciclado de nutrientes del suelo por acción microbiológica; la importancia de los microorganismos en la promoción del crecimiento vegetal y su utilización biotecnológica como alternativa para favorecer la sustentabilidad y calidad de los suelos. Además se pretende interiorizar en los conceptos relacionados con el consorcio suelo-planta-microorganismo y el objetivo de mitigar el impacto ambiental negativo causado por el uso excesivo de insumos químicos en los cultivos agrícolas, mediante la utilización de microorganismos promotores del crecimiento vegetal, que incluyen tanto a bacterias como a hongos benéficos asociados con las raíces de las plantas.</p><p> </p><p><strong>Microorganisms that enhance plant growth and soil quality. Review</strong></p><p>The present article of revision arise from theory and practical subjects developed during the course “Characterization and contribution of plant growth-promoting microorganisms in the agricultural sustainability” carried out in the Laboratory of Soil Microbiology of the Colombian Corporation of Agricultural Research (Corpoica) located in Mosquera (Cundinamarca), Colombia, in July 2010. This activity is in the framework of the Dimiagri network that includes researchers from Argentina, Brazil, Colombia, Spain, Guatemala, Mexico and Uruguay, gathered in a Coordination Action funded by the Iberoamerican Program of Science and Technology for the Development (Cyted). Aspects inherent to the growth and plant health, root system, the surrounding soil (rhizosphere), microorganisms that system partners and their contribution to sustainable management of soil-plant were analyzed in this work. Topics related to the microbial biodiversity and its effect on soil quality; nutrient cycling in the soil by microbiological activity; the importance of microorganisms in plant growthpromotion and their biotechnological application as an alternative to favor sustainability and soil quality were presented. The aim of this review is to show important concepts related to the soil-plant-microorganism system, which will allow to achieve the general objective: to mitigate the negative environmental impact due to the excessive use of chemical products on agricultural crops by using plant growth-promoting microorganisms, including bacteria and beneficial fungi associated to plant roots.</p>
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Chappe, P., A. Mourey, and J. Manem. "La microflore de boues aérobies acclimatées à des teneurs élevées en graisse." Revue des sciences de l'eau 7, no. 4 (2005): 395–404. http://dx.doi.org/10.7202/705208ar.
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Le travail présenté dans cet article a pour but d'isoler les principaux micro-organismes impliqués dans la biodégradation des lipides concentrés dans des réacteurs spécifiques de stations d'épuration des eaux et d'étudier leur action sur ce type de substrat. La microflore d'une boue activée « classique » est comparée à celle de boues acclimatées à des teneurs élevées en lipides selon un nouveau procédé « BIOMASTER® G ». Cela montre un enrichissement en bactéries fortement lipolytiques dans le système à l'équilibre. En effet, la boue activée « classique » ne contient aucun microorganisme fortement lipolytique alors qu'à partir de la boue acclimatée du même site on a pu en isoler, Acinetobacter calcoaceticus et Pseudomonas putida étant les constituants les plus actifs. L'utilisation de bioadditifs du commerce pour l'ensemencement des pilotes au lancement du système ne semble pas apporter d'avantages décisifs puisqu'on ne retrouve pas à l'équilibre les micro-organismes contenus dans ces bioadditifs. Par contre, d'autres microorganismes à pouvoir lipolytique élevé sont détectés tels que Pseudomonas sp., Aeromonas hydrophila et Staphylococcus sp . Le genre Pseudomonas est par ailleurs presque toujours rencontré quelle que soit la boue acclimatée examinée. De même, on peut noter la quasi absence de bactéries Gram positif. Tous les isolats Gram négatif dégradent plus ou moins les acides gras de longueur de chaîne variée. Le seul isolat Gram positif est inhibé ou même tué par les acides gras à chaîne moyenne ou courte et cela peut contribuer à la pauvreté en bactéries Gram positif dans les boues acclimatées. Les genres principaux que nous avons rencontrés, Pseudomonas, Acinetobacter et Aeromonas, sont capables d'assurer à la fois la lipolyse (libération des acides gras) et l'oxydation subséquente des acides gras. L'enrichissement naturel de la microflore lipolytique des boues activées dans le procédé aboutit à une microflore acclimatée capable d'assurer la biodégradation complète des lipides.
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Reni Ustiatik, Yulia Nuraini, Suharjono, and Eko Handayanto. "Isolation of Mercury-Resistant Endophytic and Rhizosphere Microorganisms from Grasses in Abandoned Gold Mining Area." Jurnal Agronomi Indonesia (Indonesian Journal of Agronomy) 49, no. 1 (2021): 97–104. http://dx.doi.org/10.24831/jai.v49i1.32356.
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There were about 900 hotspots of artisanal and small scale gold mining (ASGM) in Indonesia that recovered gold through amalgamation and cyanidation techniques. Amalgamation technique causes mercury (Hg) pollution to the soil. This study was a preliminary study that aimed to isolate Hg-resistant endophytic and rhizosphere microorganisms from pioneer grasses in the Hg-polluted soil. The most potential microorganism will be used for Hg phytoremediation in the future study. Pioneer grasses were collected from the abandoned gold mining area in Central Lombok Regency, West Nusa Tenggara. Total microorganisms were counted using Colony Forming Unit (CFU) or Standard Plate Count. The microorganism colony was characterized based on morphological characteristics. Hg-resistant endophytic and rhizosphere microorganisms were successfully isolated from pioneer grass (Cynodon dactylon and Eleusine indica) in the study site. The colonies of rhizosphere microorganisms were diverse morphologically compared to endophytic microorganisms based on the number of isolated microorganisms, 20 isolates and 17 isolates, respectively. The density of rhizosphere microorganisms was higher (96%) than endophytic microorganisms (4%). The density of rhizosphere bacteria and fungi were 47x103 and 2x103 CFU g-1, respectively. However, the density of endophytic bacteria and fungi were only 2x103 and 1x103 CFU g-1, respectively.
Keywords: endophytic microorganism, Hg-resistant, microorganism density, rhizosphere microorganism
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Švedienė, Jurgita, Vitalij Novickij, Rokas Žalnėravičius, et al. "Antimicrobial Activity of L-Lysine and Poly-L-Lysine with Pulsed Electric Fields." Applied Sciences 11, no. 6 (2021): 2708. http://dx.doi.org/10.3390/app11062708.
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For the first time, the possibility to use L-lysine (Lys) and poly-L-lysine (PLL) as additives with pulsed electric fields (PEF) for antimicrobial treatment is reported. The antimicrobial efficacy of Lys and PLL for Escherichia coli, Staphylococcus aureus, Trichophyton rubrum and Candida albicans was determined. Inactivation of microorganisms was also studied by combining Lys and PLL with PEF of 15 and 30 kV/cm. For PEF treatment, pulses of 0.5, 1, 10 or 100 μs were applied in a sequence of 10 to 5000 at 1 kHz frequency. The obtained results showed that 100 μs pulses were the most effective in combination with Lys and PLL for all microorganisms. Equivalent energy PEF bursts with a shorter duration of the pulse were less effective independently on PEF amplitude. Additionally, various treatment susceptibility patterns of microorganisms were determined and reported. In this study, the Gram-negative E. coli was the most treatment-resistant microorganism. Nevertheless, inactivation rates exceeding 2 log viability reduction were achieved for all analyzed yeast, fungi, and bacteria. This methodology could be used for drug-resistant microorganism’s new treatment development.
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Ekamaida, Ekamaida. "Sistem Intensifikasi Tanaman Padi SRI Melalui Pemanfaatan Mikroorganisme Lokal Dalam Pembuatan Kompos Dapat Meningkatkan Populasi Mikroba Tanah (Studi Kasus Di Desa Sidodadi Kabupaten Deli Serdang)." Jurnal Agrium 10, no. 2 (2018): 56. http://dx.doi.org/10.29103/agrium.v10i2.497.
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System of Rice Intensification (SRI) by a Local Microorganisme Usage (MOL) in Producing the Compost Fertilizer (Case Study at Desa Sidodadi Kabupaten Deli Serdang) is expected to maintain the fertile of land, improve land microbia population and to preserve the environment at once capable to maintain or improve land productivity. The agriculture system with SRI is applied by using organic material such as fruif waste whis is fermented to produced MOL used as decomposer in composing proges. This reseach studied microbia population where an organik agricaltural system (SRI) has been applied. The reseach was comparedl of mikroba population soil also whith how effect SRI aplication between chemical fertilizer for the managemental in Sidodadi village.Using compost MOL at SRI improved microbia population soil by the result of soil analysis either chemically and biologically the uses of MOL compost is far better compared for environmental the uses of an-organic fertilizer. The SRI pattern practiced at Desa Sidodadi was an agricultural work environmentally friendly using organic fertilizer as source of nutrients improve physical, chemical and biological properties of soil as well in increasing production yield.
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Ardina, Ardina, and Suprianto Suprianto. "Formulasi Sabun Cair Antiseptik Ekstrak Etanol Daun Seledri (Apium graveolens L.)." Jurnal Dunia Farmasi 2, no. 1 (2019): 21–28. http://dx.doi.org/10.33085/jdf.v2i1.4393.
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Pendahuluan: Tangan merupakan media yang sangat mudah untuk penyebaran penyakit dan infeksi pada manusia karena tangan sering melakukan kontak dengan lingkungan, terutama pada bagian kulit tangan yang paling sering digunakan sehingga rawan terhadap kontaminasi, sebab itu dibutuhkannya sabun pencuci tangan cair yang diyakini dapat membersihkan tangan dari microorganisme. Berawal dari hal tersebut, maka penelitian terkait inovasi sabun cuci tangan cair dengan penambahan bahan alam dilakukan. Bahan alam yang dipilih adalah daun seledri yang mengandung saponin, flavonoid. Tujuan: Untuk mengetahui formulasi menggunakan ekstrak daun saledri (Apium graveolens L. ) sebagai antiseptik sabun cair. Metode: Penelitian ini menggunakan eksperimental untuk meneliti sedian sabun cair dengan konsentrasi 0%, 2,5%, 5%, 7,5% . Berdasarkan hasil yang di uji pH dan organoleptis terdapat pengaruh perbedaan warna dan uji pH pada sedian sabun cair menunjukkan semakin besar konsentrasi dalam sedian sabun cair semakin rendah pH kulit yang didapatkan. Hasil: Hasil pemeriksaan penampilan masing-masing formula sediaan sabun cair yang paling bagus konsentrasi 2,5% .Tidak terjadi perubahan bau, warna, pH kulit berkisar antara 5,0-6,5 dan tidak terjadinya iritasi pada kulit sukarelawan. Kesimpulan: Penelitian yang telah dilakukan menunjukkan bahwa daun seledri dapat diformulasikan sebagai sabun cair antiseptik bentuk sediaan cair untuk pemakaian tangan.
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Nottingham, Charles U., Mark A. Assmus, Alexander W. Peters, et al. "Next generation sequencing in patients with nephrolithiasis: how does it perform compared with standard urine and stone cultures?" Therapeutic Advances in Urology 13 (January 2021): 175628722199497. http://dx.doi.org/10.1177/1756287221994972.
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Background: Our aim was to compare microorganism detection between standard culture (Ctx) and next generation sequencing (NGS) in patients undergoing surgery for nephrolithiasis; we prospectively compared both urine and stone culture results using these two techniques. Methods: We prospectively compared microorganism detection of urine and stone cultures using Ctx versus NGS in patients undergoing surgery for nephrolithiasis. We analyzed preoperative voided urine (Voided) using both Ctx and NGS. Intraoperatively, renal stone (Stone) cultures were analyzed with Ctx and NGS. The primary outcome was concordance in microorganism detection between Voided Ctx and Stone NGS, as well as between Stone Ctx and Stone NGS. Results: We prospectively evaluated 84 patients. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of Voided Ctx predicting Stone Ctx were 66.7%, 73.7%, 54.5%, and 82.4%, respectively. Concordance of Voided Ctx microorganisms to Stone microorganisms decreased when NGS was used for the Stone compared with Ctx. The sensitivity, specificity, PPV, and NPV of Voided NGS to predict Stone Ctx microorganisms were 85.2%, 24.6%, 34.8%, and 77.8%, respectively. The concordance of Voided NGS to Stone microorganisms improved when the Stone was analyzed via NGS compared with Ctx. Conclusion: NGS has a higher detection rate of microorganisms than standard culture for both preoperative urine and stone cultures. Voided NGS was the most sensitive in predicting a positive Stone sample, but the specificity and PPV were, overall, low. Further correlation of NGS microorganism detection with patient outcomes will determine which clinical situations may benefit most from NGS versus standard culture in patients with urinary-tract stones.
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Hirata, Tsuyoshi, Kiyoshi Kawamura, Kazuyoshi Yano, et al. "Removal Efficiencies of Microorganisms in Wastewater Treatment Processes." Water Science and Technology 28, no. 7 (1993): 55–61. http://dx.doi.org/10.2166/wst.1993.0142.
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The removal characteristics of indigenous microorganisms in wastewater treatment unit processes were studied at five operating wastewater treatment plants. The removal efficiencies of the selected microorganisms in each unit process were dependent upon not only the systems but also the kinds of microorganisms. In almost all processes, the removal efficiencies of total coliforms were similar to or higher than those of Clostridium perfringens except for filtration processes. In the additional survey, focussed on the comparison of removal efficiencies of total coliforms, Cl. perfringens and coliphages, little difference was found between CL perfringens and coliphages. From these results, it may be suggested that CL Perfringens is an effective indicator microorganism for evaluating microorganism removal in wastewater treatment processes and systems.
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Hapsoh, Gusmawartati, and Muhammad Yusuf. "Effect Various Combination of Organic Waste on Compost Quality." Journal of Tropical Soils 20, no. 1 (2016): 59–65. http://dx.doi.org/10.5400/jts.2015.v20i1.59-65.
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Municipal solid waste and agricultural waste have different ratio C/N and nutrients contents. They can be used as compost row materials. The purpose of the research was to get an optimum combination of both wastes to improve compost quality, to meet the Indonesian National Standard 19-7030-2004. Composting process use pots. The treatments were twelve combination of municipal solid waste (garbage market, household waste, restaurant waste) and agricultural waste (rice straw, empty fruit bunches of oil palm, cassava peel, banana skin) with a ratio of 1:1 and enriche by chicken manure, cow manure, wood ash and cellulolytic microorganisme. The treatment were replicated three times. The results showd that the nutrients content of compost were 0.77 to 1.19% nitrogen, 0.23 to 0.30% phosphorus, 0.46 to 0.69% potassium and 15.48 to 34.69% organic matter. The combination of agricultural waste and municipal solid waste affected the quality of compost. Compost that meets SNI 19-7030-2004 is a combination of rice straw+market waste that contains 1.12% nitrogen, 0.28% phosphorus, 0.63% potassium, ratio C/N 19.50, pH 7.42, and organic matters 37.65%. [How to Cite: Hapsoh, Gusmawartati, and M Yusuf. 2015. Effect Various Combination of Organic Waste on Compost Quality. J Trop Soils 19: 59-65. Doi: 10.5400/jts.2015.20.1.59][Permalink/DOI: www.dx.doi.org/10.5400/jts.2015.20.1.59]
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Benaroyo, Lazare. "La contribution de Friedrich Wilhelm Zahn (1845—1904) à l'étude de l'inflammation." Gesnerus 48, no. 3-4 (1991): 395–408. http://dx.doi.org/10.1163/22977953-0480304013.
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Avant d’être appelé à occuper la première chaire de pathologic à l'Universitc de Genève, Friedrich Wilhelm Zahn a publié en 1871 sa these de doctoral intitules: Zur Lehre von der Entzündung und Eiterung. Ce travail, rédigé sous la direction d’ Edwin Klebs, à Berne, démontre expërimentale merit que le prétendu Microsporon septicum (un champignon infectieux identifié par ce dernier) provoque une inflammation locale ainsi que Fapparition de foyers de suppuration secondaires, a distance. Cette étude confirme apparemment Fhypothèse de Klebs selon laquelle le Microsporon septicum, habituellement present dans les plates, est la cause d' une maladie infectieuse. La recherche de Zahn fait d’emblée Fob jet d’une critique, également adressée à Klebs : V identification du microorga-nisme, de rnëme que la demonstration de son action causale ne s ont pas concluan-tes. A Fissue du debat, il est admis qu’un microorganisme ne pent être la cause d'un état infectieux qu'aux deux conditions suivantes: il doit être considéré comme identifié selon la méthode de Koch, et la relation causale qui l'unit à la maladie infectieuse doit être spédfique. C’est ce que la thèse de Zahn n’est précisément pas parvenue a dérnontrer. L’analyse du contenu de cette recherche ainsi que des critiques qu’elle a suscitées nous permet de mettre en lumière les divers arguments qui ont alimenté la controverse sur la cause de l'inflammation et de la suppuration ä l'aube de l'ère bactériologique.
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Isaieva, H. O., M. M. Mishyna, M. O. Gonchar, O. L. Logvinova, and M. A. Basiuk. "Microorganisms causing respiratory diseases in children in relation to age and diagnosis." Regulatory Mechanisms in Biosystems 11, no. 4 (2020): 552–56. http://dx.doi.org/10.15421/022085.
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Community-acquired pneumonia (CAP) in children is still one of the leading causes of morbidity and mortality, especially in developing countries. The World Health Organization (WHO) has reported that pneumonia accounts for 15% of all deaths of children under 5 years old. The aim of the present study was to find out the predominance of microorganisms in the respiratory tract in children. 334 strains of microorganisms were isolated: Gram-positive – 293 strains, Gram-negative – 41. From the pharynx 183 strains were isolated, from the nose – 94, from sputum – 57. Among Gram-positive microorganisms the following were isolated: Staphylococcus aureus 44 strains of microorganisms, S. epidermidis – 75, Group A β-hemolytic streptococci – 39, viridans streptococci – 55, Streptococcus pneumoniae – 34, Enterococcus faecalis – 2, Candida spp. – 38, Corynebacterium pseudodiphthericum – 6. Among Gram-negative microorganisms the following were isolated: Escherichia coli 4 strains of microorganisms, Klebsiella pneumoniae – 13, Pseudomonas aeruginosa – 6, Haemophilus influenzae – 11, Enterobacter cloacae – 7. Children were divided by age and diagnosis into four groups: I group – children with acute bronchitis (0–5 years of age), II group – children with acute bronchitis (5–18 years of age), III group – children with CAP (0–5 years of age), IV group – children with CAP (5–18 years of age). Materials used in the research – nasal swabs, throat swabs and sputum. Microorganisms were isolated and identified using standard microbiological methods. S. aureus was the predominant microorganism isolate from the pharynx in children with bronchitis (0–5 years). Group A β-hemolytic streptococci were isolated most often from the pharynx in children with bronchitis older than 5 years and in children with CAP less than 5 years of age. S. pneumoniae was most often isolated from the pharynx in children older than 5 years of age with CAP. S. aureus was the main microorganism, isolated from the nose in children with bronchitis in all age groups; in patients with CAP it was the predominant microorganism in children older than 5 years of age. S. aureus was the predominant microorganism, isolated from sputum in children with bronchitis older than 5 years. S. pneumoniae was the predominant microorganism, isolated from sputum in children with CAP older than 5 years. The research showed that S. pneumoniae is still one of the main pathogens that cause CAP in school aged children.
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Steindel, Steven J., and Marianne K. Simon. "Characterization of Microorganism Identification in the United States in 1996." Archives of Pathology & Laboratory Medicine 125, no. 7 (2001): 913–20. http://dx.doi.org/10.5858/2001-125-0913-comiit.
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Abstract Context.—The National Inventory of Clinical Laboratory Testing Services (NICLTS) was designed to give an unbiased estimate of all patient testing performed by laboratories registered under the Clinical Laboratory Improvement Amendments in 1996. Objective.—Survey data were used to develop a profile of laboratory testing primarily intended to identify microorganisms or antibodies to these microorganisms. Design.—Estimates of the extent of microorganism identification were derived from the NICLTS database by identifying associated tests and methods. The volumes for tests performed at locations that primarily prepared blood components for distribution were excluded. Organisms of public health importance were identified from the National Notifiable Disease list maintained by the Centers for Disease Control and Prevention. Participants.—Laboratories that were enrolled in the 1996 Online Certification Survey and Reporting System, maintained by the US Health Care Finance Administration, and that performed laboratory testing in 1996. Outcome Measure.—Estimated volumes and associated confidence limits by test, method, specimen type, public health importance, and testing location. Results.—Excluding testing of the blood supply, 315 million tests (95% confidence limits, 280–354 million tests) were performed in the United States for microorganism identification. Those tests for which public health consensus requires national reporting represented 38% of this total. Although hospitals performed 46% of all microorganism identification, they only performed 33% of the testing for microorganisms of public health importance. Independent and specialty laboratories performed 38% of all testing but 65% of the testing for microorganisms of public health importance. Direct methods (methods not involving culture) were used in 77% of the tests for microorganisms of public health importance and in 42% of all identification tests. Conclusions.—The distribution of microorganism identification testing found using NICLTS data is consistent with plans to modernize the public health surveillance system in the United States.
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Wheeler, Jeanette D., Eleonora Secchi, Roberto Rusconi, and Roman Stocker. "Not Just Going with the Flow: The Effects of Fluid Flow on Bacteria and Plankton." Annual Review of Cell and Developmental Biology 35, no. 1 (2019): 213–37. http://dx.doi.org/10.1146/annurev-cellbio-100818-125119.
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Microorganisms often live in habitats characterized by fluid flow, from lakes and oceans to soil and the human body. Bacteria and plankton experience a broad range of flows, from the chaotic motion characteristic of turbulence to smooth flows at boundaries and in confined environments. Flow creates forces and torques that affect the movement, behavior, and spatial distribution of microorganisms and shapes the chemical landscape on which they rely for nutrient acquisition and communication. Methodological advances and closer interactions between physicists and biologists have begun to reveal the importance of flow–microorganism interactions and the adaptations of microorganisms to flow. Here we review selected examples of such interactions from bacteria, phytoplankton, larvae, and zooplankton. We hope that this article will serve as a blueprint for a more in-depth consideration of the effects of flow in the biology of microorganisms and that this discussion will stimulate further multidisciplinary effort in understanding this important component of microorganism habitats.
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Parmar, Amit, Rakesh Choudhary, and Krishna Agarwal. "Magnetohydrodynamics Williamson Fluid Comprising Gyrotactic Microorganisms Flows Through a Permeable Stretching Layer with Variable Fluid Properties." Journal of Nanofluids 9, no. 4 (2020): 375–87. http://dx.doi.org/10.1166/jon.2020.1762.
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The present study shows the impacts of Williamson fluid with magnetohydrodynamics flow containing gyrotactic microorganisms under the variable fluid property past permeable stretching sheet. Variable Prandtl number, mass Schmidt number, and gyrotactic microorganisms Schmidt number were all considered. The momentum, energy, mass, and microorganism equations’ governing PDEs are converted into nonlinear coupled ODEs and numerically solved with the bvp4c solver using suitable transformations. The main outcome of this study is that Williamson fluid parameter constantly decreases in velocity profile, however reverse effects can be shown in temperature profile. Also, M parameter and Kp parameter enhance the heat transfer rate, concentration rate and microorganisms boundary layer thickness but declines in momentum boundary layer thickness and velocity profile. The aim of this research is to see how velocity slide, temperature jump, concentration slip, and microorganism slip affect MHD Williamson fluid flow with gyrotactic microorganisms over a leaky surface embedded in spongy medium, with non-linear radiation and non-linear chemical reaction.
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Oliveira, Adriana Cristina de, Rafael Souza Silva, Mario E. Piscoya Díaz, and Robert Aldo Iquiapaza. "Bacterial Resistance and Mortality in an Intensive Care Unit." Revista Latino-Americana de Enfermagem 18, no. 6 (2010): 1152–60. http://dx.doi.org/10.1590/s0104-11692010000600016.
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The goal was to identify risk factors for healthcare-associated infections by resistant microorganisms and patient mortality in an Intensive Care Unit. A prospective and descriptive epidemiological research was conducted from 2005 till 2008, involving 2300 patients. Descriptive statistics, bivariate and multivariate logistic regression analysis were used. In bivariate analysis, infection caused by resistant microorganism was significantly associated to patients with community-acquired infection (p=0.03; OR=1.79) and colonization by resistant microorganism (p<0.01; OR=14.22). In multivariate analysis, clinical severity (p=0.03; OR=0.25) and colonization by resistant microorganism (p<0.01; OR=21.73) were significant. Mortality was associated to the following risk factors: type of patient, average severity index, besides mechanical ventilation. The relation between resistant microorganisms and death shows the need to monitor adherence to infection control measures so as to improve care quality and mainly survival of critical patients.
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Srinivasacharya, D., and I. Sreenath. "Bioconvection of Micropolar Fluid in an Annulus." International Journal of Mathematical, Engineering and Management Sciences 5, no. 2 (2020): 237–47. http://dx.doi.org/10.33889/ijmems.2020.5.2.019.
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This paper deals with the bioconvection of microploar fluid in an annulus containing microorganisms in which the outer cylinder is rotating. A mathematical model, with a fully coupled system of partial differential equations presenting the velocity, total mass, momentum, thermal energy, mass diffusion, and motile microorganisms is presented. A suitable transformations is adopted to reduce the governing non-linear governing to a set of non-linear ordinary differential equations and then linearized by means of successive linearization method. The resulign linearized equaions are solved using Chebyshev collocation method. The illustrating analysis of influences of the various flow governing physical parameters such as the micropolar coupling number, the bioconvection Schmidt-number, Prandtl number, Lewis number and bioconvection Peclet-number and Reynolds number on motile microorganism distribution are studied and is presented. Also, the density number of motile microorganism is examined for various governing parameters along with slip parameter of motile microorganism.
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Abdul Latiff, Nur Amalina, Md Jashim Uddin, O. Anwar Bég, and Ahmad Izani Ismail. "Unsteady forced bioconvection slip flow of a micropolar nanofluid from a stretching/shrinking sheet." Proceedings of the Institution of Mechanical Engineers, Part N: Journal of Nanomaterials, Nanoengineering and Nanosystems 230, no. 4 (2016): 177–87. http://dx.doi.org/10.1177/1740349915613817.
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The unsteady forced bioconvection boundary layer flow of a viscous incompressible micropolar nanofluid containing microorganisms over a stretching/shrinking sheet is studied numerically. A mathematical model, with the aid of appropriate transformations, is presented. The transformed non-linear ordinary differential equations are solved numerically by the Runge–Kutta–Fehlberg fourth- to fifth-order numerical method. The effect of the governing parameters on the dimensionless velocity, micro-rotation, temperature, nanoparticle volume fraction and microorganism as well as the local skin friction coefficient, the heat transfer rate and microorganisms transfer rate is thoroughly examined. The findings show that the value of skin friction and Nusselt number are decreased and microorganism number is increased as velocity slip, thermal slip and microorganism slip parameter are increased, respectively. Results from this investigation were compared with previous investigations demonstrating very good correlation. The present results are relevant to improving the performance of microbial fuel cells deploying nanofluids.
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Huang, Zhao Lin, Ping Ning, and Zhang Liu. "Microbial Inoculants of Environmental Material in the Compost Application Research Progress." Advanced Materials Research 534 (June 2012): 230–34. http://dx.doi.org/10.4028/www.scientific.net/amr.534.230.
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composting is a process of organic matter degradation and transformation achieved by microorganism, which plays a leading role during composting processes. Inoculation with proper microorganisms can raise the temperature rapidly, shorten the time of the composting, increase the degradation of organic matter and improve the quality of compost. This paper summarized the functions of microorganism inoculum and suggested that in order to solve the problems: to become the dominant strain(s) for the microorganism inoculated in the composting process; to choose the species of microorganism inoculum，the optimal inoculation quantity and the time of inoculation should be studied.
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Le, Jian Jun, Ji Yuan Zhang, Lu Lu Bai, Rui Wang, Zhao Wei Hou, and Xiao Lin Wu. "Evaluation and Application of Endogenous Microorganism Activator in Reservoir after Chemical Flooding." Advanced Materials Research 1051 (October 2014): 404–9. http://dx.doi.org/10.4028/www.scientific.net/amr.1051.404.
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To further enhance oil recovery in reservoir after chemical flooding, an efficient activator formulation for promoting metabolism of endogenous microorganism was researched. Changes in community structure, growth and metabolites of endogenous microorganism were analyzed by methods of aerogenic experiments, physical simulation experiments, electron microscopy scanning (SEM), T-RFLP and Pyrophosphate sequencing. To evaluate whether endogenous microorganism activator screened in laboratory could activate endogenous microorganisms and enhance oil recovery in reservoirs after polymer flooding. The flooding effect and mechanism were studied, and this activator was used in a testing well group in Daqing oilfield. The results of the aerogenic experiments showed that the activator could activate the endogenous microorganisms in the injected water and make them produce a lot of biogas. The pressurized gas reached 2MPa after 60d static culture of activator in a high pressure vessel. The results showed that the activator could activate the endogenous microorganisms in the injected sewage and make them have a lot of growth and reproduction in the core and physical simulation of natural core flooding experiment. In the field test,the incremental oil production was 5957 t while the water content declined by 2.2% after injecting the activator, which provides an effective way to further enhance oil recovery in reservoir after chemical flooding.
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Yang, Lv, Chen Guang Liu, Bai Lin Fu, and Jia Wei. "Identification, Analysis of Fungal Microorganisms on Filter of Central Air Conditioning System." Advanced Materials Research 955-959 (June 2014): 565–68. http://dx.doi.org/10.4028/www.scientific.net/amr.955-959.565.
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As air conditioning system long-time running, microorganism like bacterium and fungus propagates easily in high humidity environment such as filter equipment. After the microorganism entering indoor environment through air conditioning system, the air quality would be affected seriously. Air conditioning system which is regarded as potential microbial pollution source is becoming more attention. The study was about isolation and identification of fungal microorganisms on the filter surface of the central air conditioning system in a gymnasium, and then researching on the colonies and mycelium grown and reproduce regular of fungal microorganisms in different thermal environment using thermal methods, aim to lay groundwork of propagation and diffusion mechanism study of fungal microorganisms in air conditioning system and effective air microbial contamination solve by thermal methods. By physiology biochemistry experiment and molecular biological identification, it was shown that the dominant fungi were Penicillium spp. and Cladosporium spp., colonies were 600 cfu/cm2 and 140 cfu/cm2 respectively.
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Endo, G., and Y. Tohya. "Ecological Study on Anaerobic Sludge Bulking Caused by Filamentous Bacterial Growth in an Anaerobic Contact Process." Water Science and Technology 20, no. 11-12 (1988): 205–11. http://dx.doi.org/10.2166/wst.1988.0286.
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The authors observed a biological sludge bulking phenomenon which was caused by filamentously growing anaerobic microorganisms in experimental anaerobic contact processes (ACP) treating wheat starch wastewater. There are many kinds of anaerobic microorganisms which grow filamentously, like in activated sludge. One species of anaerobic bacteria caused serious sludge bulking, and it had thin rod (around 0.2 µ m in width) and long chained morphology. When acidogenically fermented starch wastewater was fed to the ACP, the thin rod microorganism was eliminated and the biomass concentration of the methanogenic fermentor was recovered. The microorganism which caused bulking phenomenon was enriched in a liquid medium containing raw starch (wheat starch particle). The microorganism grew in long chained filamentous form, degraded raw starch, and fermented mainly volatile fatty acids (acetate, propionate, butyrate and ethanol). From these results, it is revealed that acidogenic fermentation of wastewater containing raw starch prior to treatment by an ACP is effective to prevent the anaerobic sludge bulking and to keep high organic laoding of ACPs.
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ELAD, DANIEL. "Risk Assessment of Malicious Biocontamination of Food." Journal of Food Protection 68, no. 6 (2005): 1302–5. http://dx.doi.org/10.4315/0362-028x-68.6.1302.
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Throughout the last decades of the 20th century, the biological threat evolved from primarily a government-controlled weapon to a tool of terrorism. One of the consequences of this trend is the near impossibility of foreseeing when and how an act of bioterrorism will occur. The suitability of food products for such an act stems from the multitude of microorganisms that may be used for contamination and the vulnerability of the products during and after processing. Tests that would enable the detection of a large variety of microorganisms quickly, reliably, and economically should also provide satisfactory means to prevent acts of malicious biocontamination of food products. Until such means become available, a priority-based approach to the problem is probably the most practical. Priorities should be determined based on a systematic risk assessment to define the relative likelihood of a certain microorganism being used in an act of malicious food contamination. Criteria to be evaluated are availability, weaponization processes, delivery of an effective dose, probability of early detection, and the microorganism's resistance to the conditions to which it will be exposed. Because the results of such an assessment may vary according to prevailing conditions, the assessment must be based on the existing circumstances. The results of the assessment should then be applied to the various procedures of food processing, which should further reduce the number of potential microbial threats. Existing methods of screening food for contaminating microorganisms and existing food safety and security procedures such as hazard analysis and critical control point programs may have to be modified to become suitable for the detection of acts of bioterrorism.
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Jeksen, Julianus, and Charly Mutiara. "PENGARUH SUMBER BAHAN ORGANIK YANG BERBEDA TERHADAP KUALITAS PEMBUATAN MIKROORGANISME LOKAL (MOL)." AGRICA 11, no. 1 (2018): 60–72. http://dx.doi.org/10.37478/agr.v11i1.23.
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This study aims to determine the content of microorganisms from local microorganisms and determine their quality. This research is a descriptive study, where the results of the analysis of microbial content are described by the standard microbial content in Local Microorganisms. The results showed that Local Microorganisms from the leaves of Kirinyu, Gamal, Lamtoro and vegetables wastes contained Lactobacillus, Saccharomyces mushrooms, Actinomycetes fungi, and phosphate solvent bacteria (BPF). Local microorganisms from these materials have not been able to produce good quality because they are still lower than the minimum technical requirements based on Minister of Agriculture Regulation number 70 of 2011, while Saccharomyces mushroom microorganism content, pH and phosphate solvent bacteria (BPF) are in accordance with technical requirements all types of local microorganisms positively contain phosphate solvent bacteria (BPF).
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Xiong, Qiangqiang, Jinlong Hu, Haiyan Wei, Hongcheng Zhang, and Jinyan Zhu. "Relationship between Plant Roots, Rhizosphere Microorganisms, and Nitrogen and Its Special Focus on Rice." Agriculture 11, no. 3 (2021): 234. http://dx.doi.org/10.3390/agriculture11030234.
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Fertilization is an important practical measure in agricultural production. As an important nutrient element of plants, nitrogen (N) has a significant impact on the plant productivity and microbial function. Rhizosphere microorganisms affect plant growth and development, nitrogen uptake and utilization, and ecological adaptability. The interaction mechanism between plant and rhizosphere microorganisms is one of the hotspots in life science research and the key program of agricultural microorganism utilization. In this article, the relationship among plant root morphology and physiology, rhizosphere microorganisms, and nitrogen is reviewed, summarized, and prospected.
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Schweitzer, Jennifer A., Joseph K. Bailey, Dylan G. Fischer, et al. "PLANT–SOIL–MICROORGANISM INTERACTIONS: HERITABLE RELATIONSHIP BETWEEN PLANT GENOTYPE AND ASSOCIATED SOIL MICROORGANISMS." Ecology 89, no. 3 (2008): 773–81. http://dx.doi.org/10.1890/07-0337.1.
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Kradtap, Supaporn, C. Ajith Wijayawardhana, Kevin T. Schlueter, H. Brian Halsall, and William R. Heineman. "“Bugbead”: an artificial microorganism model used as a harmless simulant for pathogenic microorganisms." Analytica Chimica Acta 444, no. 1 (2001): 13–26. http://dx.doi.org/10.1016/s0003-2670(01)01152-7.
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Guo, Qingqing, Jun Yu, Jingguo Sun, et al. "Exogenous Inoculation of Microorganisms Effect on Root Exudates and Rhizosphere Microorganism of Tobaccos." Advances in Microbiology 11, no. 09 (2021): 510–28. http://dx.doi.org/10.4236/aim.2021.119038.
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Chaudhary, Renu, Meenakshi Balhara, Mrridula Dangi, Mehak Dangi, and Anil K. Chhillar. "RHIZOSPHERE MICROBIOME: AN EMERGING FRONTIER IN CAUSING AND CURING INFECTIOUS DISEASES." Asian Journal of Pharmaceutical and Clinical Research 11, no. 6 (2018): 65. http://dx.doi.org/10.22159/ajpcr.2018.v11i6.25299.
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Prevalence of pathogenic microorganisms in the rhizosphere causing infectious diseases in plants and humans has increased considerably due to a high content of nutrients. Such pathogenic infections are of huge concern in agriculture, health care, and medical arenas. Rhizosphere microbiome is a “microbial hotspot,” not only for pathogenic microorganism but also for unlimited beneficial microorganisms. Therefore, this microbiome has immense potential in the shaping of earth from natural vegetation to the intense agricultural production to human health. Rhizosphere microorganism from unexplored habitats is a promising approach to overcome the escalating threat of such pathogenic infections. Hence, efforts are being made to isolate more and more rhizobacteria that are beneficial for better plant productivity and for treating human diseases. Thus, present review highlights and discusses the available literature on beneficial/pathogenic microorganisms belonging to rhizosphere and their impact on plants and human diseases. Furthermore, it sheds light on how this novel knowledge helps in deriving maximum benefits out of this naturally occurring population for the betterment of plant and human health.
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Lu, Xiaoling, Xiaoyu Liu, Cong Long, et al. "A Preliminary Study of the Microbial Resources and Their Biological Activities of the East China Sea." Evidence-Based Complementary and Alternative Medicine 2011 (2011): 1–8. http://dx.doi.org/10.1155/2011/806485.
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East China Sea is one of the four sea areas in China, which possesses peculiar ecological environment and many kinds of living creatures, especially the microorganisms. We established the East China Sea microorganism library (during 2006–2010) for the first time, which stored about 30000 strains that covered most kinds of the species. In this paper, 395 pure strains of East China Sea microorganism library which belong to 33 different genera were mainly introduced.Sulfitobacter,Halomonas,Bacillus,Pseudoalteromonas, andIdiomarinawere the most dominant species. On the large-scale biological activity screening of the 395 strains, 100 strains possess different biological activities based on different screening models, of which 11.4% strains have antibacterial activities, 15.9% have cytotoxicity activities, and 6.1% have antioxidation activities. Besides, the secondary metabolites of 6 strains with strong biological activities were studied systematically; diketopiperazines and macrocyclic lactones are the active secondary metabolites. The species and the biological activity of microorganisms diversity, the abundant structure type of the secondary metabolites, and their bioactivities all indicate that East China Sea is a potent marine microorganisms-derived developing resource for drug discovery.
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Kumari, Pallavi, Tali Sayas, Patricia Bucki, Sigal Brown-Miyara, and Maya Kleiman. "Real-Time Visualization of Cellulase Activity by Microorganisms on Surface." International Journal of Molecular Sciences 21, no. 18 (2020): 6593. http://dx.doi.org/10.3390/ijms21186593.
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A variety of methods to detect cellulase secretion by microorganisms has been developed over the years, none of which enables the real-time visualization of cellulase activity on a surface. This visualization is critical to study the interaction between soil-borne cellulase-secreting microorganisms and the surface of plant roots and specifically, the effect of surface features on this interaction. Here, we modified the known carboxymethyl cellulase (CMC) hydrolysis visualization method to enable the real-time tracking of cellulase activity of microorganisms on a surface. A surface was formed using pure CMC with acridine orange dye incorporated in it. The dye disassociated from the film when hydrolysis occurred, forming a halo surrounding the point of hydrolysis. This enabled real-time visualization, since the common need for post hydrolysis dyeing was negated. Using root-knot nematode (RKN) as a model organism that penetrates plant roots, we showed that it was possible to follow microorganism cellulase secretion on the surface. Furthermore, the addition of natural additives was also shown to be an option and resulted in an increased RKN response. This method will be implemented in the future, investigating different microorganisms on a root surface microstructure replica, which can open a new avenue of research in the field of plant root–microorganism interactions.
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Saleem, S., Hunza Rafiq, A. Al-Qahtani, Mohamed Abd El-Aziz, M. Y. Malik, and I. L. Animasaun. "Magneto Jeffrey Nanofluid Bioconvection over a Rotating Vertical Cone due to Gyrotactic Microorganism." Mathematical Problems in Engineering 2019 (May 12, 2019): 1–11. http://dx.doi.org/10.1155/2019/3478037.
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The particular inquiry is made to envision the behavioral characteristics of gyrotactic microorganism effects on the MHD flow of Jeffrey nanofluid. Together the nanoparticles and motile microorganism are inducted into the modeled nonlinear differential equations. The optimal solutions for the governing equations are tackled by optimal homotopy analysis method. The physical characteristics of the relatable parameters are explored and deliberated in terms of graphs and numerical charts. Also, the precision of the present findings is certified by equating them with the previously published work. It is explored that rescaled density of the motile microorganisms contracts with bioconvection Peclet number Pe. It is seen that bioconvection Rayleigh number Rb shrinks the magnitude of tangential velocity. Also, bioconvection Schmidt number Sb augments the reduced density number of the motile microorganisms.
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BUENO, DANTE J., CÉSAR H. CASALE, ROMINA P. PIZZOLITTO, MARIO A. SALVANO, and GUILLERMO OLIVER. "Physical Adsorption of Aflatoxin B1 by Lactic Acid Bacteria and Saccharomyces cerevisiae: A Theoretical Model." Journal of Food Protection 70, no. 9 (2007): 2148–54. http://dx.doi.org/10.4315/0362-028x-70.9.2148.
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The ability of lactic acid bacteria (LAB) and Saccharomyces cerevisiae to remove aflatoxin B1 (AFB1) from liquid medium was tested. The experimental results indicated that (i) AFB1 binding to microorganisms was a rapid process (no more than 1 min); (ii) this binding involved the formation of a reversible complex between the toxin and microorganism surface, without chemical modification of the toxin; (iii) the amount of AFB1 removed was both toxin- and bacteria concentration–dependent; and (iv) quantitatively similar results were obtained with viable and nonviable (heat-treated) bacteria. According to these details, a physical adsorption model is proposed for the binding of AFB1 to LAB and S. cerevisiae, considering that the binding (adsorption) and release (desorption) of AFB1 to and from the site on the surface of the microorganism took place (AFB1 + S ↔ S − AFB1). The model permits the estimation of two parameters: the number of binding sites per microorganism (M) and the reaction equilibrium constant (Keq) involved, both of which are useful for estimating the adsorption efficiency (M × Keq) of a particular microorganism. Application of the model to experimental data suggests that different microorganisms have similar Keq values and that the differences in toxin removal efficiency are mainly due to differences in M values. The most important application of the proposed model is the capacity to select the most efficient microorganism to remove AFB1. Furthermore, it allows us to know if a modification of the adsorption efficiency obtained by physical, chemical, or genetic treatments on the microorganism is a consequence of changes in M, Keq, or both.
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Guzik, Hillary, and Kessler McCoy-Simandle. "Modeling Microorganism Transmission with Madagascar Hissing Cockroaches: An Inquiry Activity." American Biology Teacher 79, no. 5 (2017): 365–74. http://dx.doi.org/10.1525/abt.2017.79.5.365.
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Students will test Madagascar hissing cockroach's capacity as a vector for transmission of microorganisms. By comparing a cockroach exposed to human contact (handled by students) and a cockroach with limited exposure (not handled), students can assess the ability of cockroaches to transmit microorganisms from one location (hands) to another (agar plate where the microorganism will be grown). This will allow students to determine if the Madagascar hissing cockroach, the classroom pet, is a potential vector for microorganisms. Students then will be able to question and relate the concept of insects and objects as vectors for common pathogen transfer.
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Ali, Liaqat, Xiaomin Liu, Bagh Ali, Saima Mujeed, and Sohaib Abdal. "Finite Element Simulation of Multi-Slip Effects on Unsteady MHD Bioconvective Micropolar Nanofluid Flow Over a Sheet with Solutal and Thermal Convective Boundary Conditions." Coatings 9, no. 12 (2019): 842. http://dx.doi.org/10.3390/coatings9120842.
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In this article, the intention is to explore the flow of a magneto-hydrodynamic (MHD) bioconvective micro-polar Nanofluid restraining microorganism. The numerical solution of 2-D laminar bioconvective boundary layer flow of micro-polar nanofluids are presented. The phenomena of multi-slip, convective thermal and Solutal boundary conditions have been integrated. A system of non-linear partial differential equations are transformed into the system of coupled nonlinear ordinary differential equations by applying appropriate transformations, the transformed equations are then solved by applying the variational finite element method (FEM). The fascinating features of assorted velocity parameter, microrotation, temperature, microorganism compactness, solutal and nanoparticles concentration have been inspected. The rate of heat transfer, the skin friction coefficient, couple stress and Sherwood number for microorganisms have also been discussed graphically and numerically. The investigations illustrated that increase in material parameters causes a reduction in microorganism compactness, concentration and temperature. As a result of enhancement in the unsteadiness parameter, the fluid velocity, concentration of microorganisms and the temperature are observed to be declines. Energy and microorganism compactness profile affected by the improvement in the buoyancy ratio parameter. As the improvement in results of buoyancy ratio parameter effects on improvement in the energy and the microorganism compactness profile while the velocity profile is condensed. In the end, rationalized convergence of the finite element solution has been inspected; the computations are found out via depreciating the mesh size.
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Elogail, M. A., and Kh S. Mekheimer. "Modulated Viscosity-Dependent Parameters for MHD Blood Flow in Microvessels Containing Oxytactic Microorganisms and Nanoparticles." Symmetry 12, no. 12 (2020): 2114. http://dx.doi.org/10.3390/sym12122114.
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This work’s primary purpose is to implement a numerical study that simulates blood flow through a microvessel involving oxytactic microorganisms and nanoparticles. The oxytactic microorganisms exhibit negative chemotaxis to gradients of oxygen (oxygen repellents). These microorganisms are to batter infected hypoxic tumor cells as drug-carriers. The viscosity of blood is to vary with temperature, shear-thinning, and nanoparticle concentration. We have formulated a mathematical model then simplified it under assumptions of long wavelength and low Reynold’s number. The resulting non-linear coupled differential equation system is solved numerically with the MATHEMATICA software aid using the built-in command (ParametricNDSolve). This study treated all non-dimensional parameters defined in terms of viscosity to be variables (VP-Model), unlike some previous literature attempts that have considered these parameters mentioned above as constants (CP-Model). The achieved results assured the reliability of the (VP-Model) over the (CP-Model). Our results reveal that temperature and microorganism density increase with the thermophoresis parameter. The impact of increasing the Brownian motion parameter is to increase temperature and lessen microorganism density. Outcomes also indicate an enhancement in the microorganism density towards the hypoxic tumor regions located aside the microvessel walls by boosting oxygen concentrations in the streamflow. The current study is believed to provide further opportunities to improve drug-carrier applications in hypoxic tumor regions by better recognizing the flow features, heat, and mass transfer in such zones.
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ALWAZEER, DURIED, REMY CACHON, and CHARLES DIVIES. "Behavior of Lactobacillus plantarum and Saccharomyces cerevisiae in Fresh and Thermally Processed Orange Juice." Journal of Food Protection 65, no. 10 (2002): 1586–89. http://dx.doi.org/10.4315/0362-028x-65.10.1586.
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Lactobacillus plantarum and Saccharomyces cerevisiae are acid-tolerant microorganisms that are able to spoil citrus juices before and after pasteurization. The growth of these microorganisms in orange juice with and without pasteurization was investigated. Two samples of orange juice were inoculated with ca. 105 CFU/ml of each microorganism. Others were inoculated with ca. 107 CFU/ml of each microorganism and then thermally treated. L. plantarum populations were reduced by 2.5 and <1 log10 CFU/ml at 60°C for 40 s and at 55°C for 40 s, respectively. For the same treatments, S. cerevisiae populations were reduced by >6 and 2 log10 CFU/ml, respectively. Samples of heated and nonheated juice were incubated at 15°C for 20 days. Injured populations of L. plantarum decreased by ca. 2 log10 CFU/ml during the first 70 h of storage, but those of S. cerevisiae did not decrease. The length of the lag phase after pasteurization increased 6.2-fold for L. plantarum and 1.9-fold for S. cerevisiae, and generation times increased by 41 and 86%, respectively. The results of this study demonstrate the differences in the capabilities of intact and injured cells of spoilage microorganisms to spoil citrus juice and the different thermal resistance levels of cells. While L. plantarum was more resistant to heat treatment than S. cerevisiae was, growth recovery after pasteurization was faster for the latter microorganism.
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Angarita Merchán, Maritza, Giselle Di Filippo Iriarte, Diana Patricia Mora Moreno, and Atilio Junior Ferrebuz Cardozo. "Perfil de resistencia de microorganismos circulantes en una Institución Prestadora de Servicios de salud en el Departamento de Boyacá, 2018." Revista Investigación en Salud Universidad de Boyacá 6, no. 1 (2019): 120–44. http://dx.doi.org/10.24267/23897325.327.
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Introducción. La resistencia bacteriana ha tomado importancia en salud pública, requiriendo establecer las relaciones existentes entre las infecciones, el manejo terapéutico y la expresión de los mecanismos de resistencia en microorganismos aislados en muestras hospitalarias. Objetivo. Reportar el perfil de resistencia de los microorganismos identificados en una institución prestadora de servicios de salud de tercer y cuarto nivel de atención en el Departamento de Boyacá durante un periodo de 6 meses en el año 2018. Materiales y métodos. Se llevó a cabo un estudio observacional, descriptivo y de corte transversal; los microorganismos fueron aislados de muestras clínicas de una institución prestadora de salud del departamento de Boyacá durante un periodo de 6 meses en el año 2018. Se realizó identificación, concentración mínima inhibitoria y pruebas confirmatorias de susceptibilidad según la Clinical and Laboratory Standards Institute M100-S23. Resultados. En los aislados evaluados predominaron los bacilos Gram negativos con un 86,4 % de estas 50% presentaron el fenotipo de resistencia Betalactamasas de espectro extendido, siendo Escherichia coli el microorganismo más frecuente. Staphylococcus aureus fue el único microorganismo Gram positivo aislado con 100% de cepas resistente a meticilina. Conclusiones. El microorganismo aislado con mayor frecuencia fue Escherichia coli y el mecanismo de resistencia más prevalente fue la producción de Betalactamasas de espectro extendido aisladas de muestras de orina.
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Asano, H., H. Myoga, M. Asano, and M. Toyao. "A Study of Nitrification Utilizing Whole Microorganisms Immobilized by the PVA-Freezing Method." Water Science and Technology 26, no. 5-6 (1992): 1037–46. http://dx.doi.org/10.2166/wst.1992.0545.
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The particular characteristics of nitrifying bacteria are that they have a reduced tendency to flocculate, a lower specific growth rate and a higher specific nitrification rate. Accordingly, we used whole microorganisms immobilized by the PVA-freezing method (in order to prevent microorganism wash-out) to investigate the characteristics and efficiency of their nitrification. The following results were obtained.By comparsion with suspended microorganisms, the nitrification rate of immobilized microorganisms was not as affected by temperature and their storage stability was better.The nitrification efficiency of a recycling operation in a biological nitrogen removal system was compared with that of a once-through operation, using immobilized microorganisms. The results showed that the ratio of allowable volumetric loading in the recycling operation was 60% of that in the once-through operation.