Добірка наукової літератури з теми "HPTLC-bioautography"

Abstract This paper reviews the use of TLC-bioautography in the search for antifungal compounds from natural sources. The main methods used for antifungal screening are presented, with special emphasis on bioautography. Different aspects of the technique, including the latest chromatographic developments such as HPTLC and HPLC microfractionation are presented. The present status and recent advances made in antifungal bioautography are discussed, and a comprehensive review of the applications over the last 6 years is presented. Various strategies applied in the search for antifungal compounds from natural sources are discussed, with a highlight on the challenges faced when screening complex crude mixtures. The activities of approximately 100 antifungal compounds of natural origin are presented with their minimum inhibitory quantity. The most active natural source compounds against Candida, Cladosporium, Colletotrichum, and Fusarium species are highlighted, and the compound activities discussed. In addition, perspectives concerning future improvements in bioautography sensitivity and reproducibility are noted.

Abstract Background: Interest in the antioxidant and antidiabetic activity of natural products are growing vastly in the modern world. Thin layer chromatography-bioautography-mass spectroscopy (TLC-bioautography-MS) plays an important role in chemico-biological screening of natural sources. TLC combined with 2, 2-Diphenyl-1-picrylhydrazyl (DPPH) free radical, α-amylase and α-glucosidase bioassay were used to evaluate antioxidant and antidiabetic activities, respectively, in different extracts of Citrullus colocynthis (Hanzal), a well-known traditional Indian Unani medicinal plant. Objective: To develop a TLC-bioautographic-MS method for DPPH, α-amylase, and glucosidase inhibitors in different extract of C. colocynthis fruits. Method: Fruits of C. colocynthis were successively extracted with toluene, dichloromethane, ethyl acetate, methanol, and water. TLC solvents were developed, and bioautographic-MS analysis was carried out to identify the antioxidant and antidiabetic compounds. Results: HPTLC fingerprinting analysis showed maximum numbers of band separated in dichloromethane and ethyl acetate extracts of C. colocynthis, fourteen and thirteen at 254 and 366 nm, respectively. Whereas six and five separated bands were observed in toluene extract at 254 and 366 nm, respectively showed minimum numbers of metabolites. Based on TLC-bioautography-MS, maximum number of antioxidant compounds were identified in dichloromethane extract. Except aqueous extract of C. colocynthis, all the extracts have shown antidiabetic activity. On the other hand, there were no antioxidant compounds in methanolic extract of C. colocynthis. Conclusions: The results of this study reveal that TLC-bioautography-MS–guided strategy used to identify antioxidant and antidiabetic compounds of C. colocynthis is very useful technique for high-throughput screening of bioactive compounds. Highlights: TLC-MS bioautography is a simple and fast to enables bioactive compounds present in extracts.

This study was performed to determine the main antibacterial compounds of the essential oil (??) of saltmarsh plant Artemisia santonicum (Asteraceae). The combination of HPTLC and direct bioautography was used for the activity guided isolation of isogeranic acid as the main antibacterial constituent with remarkable antimicrobial activity, although it was the minor component of the EO, present only in 0.2 %, as calculated from GC/FID. Its structure was determined by 1D- and 2D-NMR and GC?MS techniques. Antibacterial activity of isogeranic acid against all tested bacteria was significantly higher than EO and even than both controls streptomycin and ampicillin. In further investigation of antibiofilm and antiquorum sensing activity EO exhibited the best inhibition of the biofilm formation at 1/8 minimal inhibitory concentration (MIC) and isogeranic acid at 1/2 MIC. Both EO and isogeranic acid possessed pyocyanin inhibitory activity showing the reduction of pigment at 60.6 and 62.8 %, respectively, at 1/2 MIC concentrations.

Abstract Background: Alpinia officinarum Hance (ginger family) is an important Chinese medicine, especially in Southern China. Objective: A simple and effective high-performance thin-layer chromatography coupled with 2, 2-diphenyl-1-picrylhydrazyl bioautography (HPTLC-DPPH) and electrospray ionization quadrupole time-of-flight tandem mass spectrometry (ESI-Q-TOF-MS/MS) method was developed for the bioactivity-based quality control of A. officinarum. Methods: The HPTLC-DPPH and ESI-Q-TOF-MS/MS were applied for the analysis of different parts of A. officinarum after using methanol extraction for 23 batches of taproot, four batches of aerial, and three batches of fibril parts. Results: The systematic evaluation showed that similar components in taproot and aerial parts make the major antioxidant activity. However, based on our evaluation, the antioxidant ability of the aerial parts is lower than the taproot parts. There is also a significant difference (P < 0.05) between taproot and fibril parts of the root. The chemical structures of compounds with the antioxidant capacity were tentatively identified as 5R-hydroxy-7-(4-hydroxy-3-methoxyphenyl)-1-phenyl-3-heptanone (band 1), kaempferide (band 2), and galangin (band 3) based on ESI-Q-TOF-MS/MS analytical results and further confirmed by standards. Conclusions: This identification indicated that two flavonoid compounds and one diarylheptanoid compound possessed high potentials to be used as the antioxidant biomarkers for the quality control of A. officinarum. Highlights: The comparison of different parts could be considered as guidelines for the usage of A. officinarum.

Cette thèse porte sur l’étude d’une méthode de criblage de bio activités de composés naturels en plein essor : l’HPTLC-bioautographie. C’est une technique couplant une séparation chromatographique et des tests d’activité biologique. La séparation des composés naturels de l’extrait à tester va s’effectuer sur une plaque d’HPTLC et cette même plaque développée va être révélée par différentes méthodes permettant de tester les activités biologiques des composés. Généralement, il existe plusieurs catégories de tests utilisables : les tests antimicrobiens, les tests enzymatiques et les tests chimiques (notamment la recherche d’antioxydants). Ce travail résulte d’un partenariat (CIFRE) entre Université Côte d’Azur et la société BotaniCert, spécialisée dans l’analyse phytochimique. La demande de la société BotaniCert souhaitant se pourvoir en méthodes de criblage d’activités a conduit à la recherche des tests d’HPTLC-bioautographie existants et développables dans un laboratoire de chimie (certains tests antimicrobiens nécessitent la manipulation d’organismes pathogènes et ne sont effectuables que dans des laboratoires adaptés). Le choix de certaines pathologies découlant d’une demande en recherche et développement a mené à l’adaptation au laboratoire de BotaniCert des plusieurs tests de criblage enzymatiques (α-glucosidase, acétylcholinestérase, lipase pancréatique) ainsi que de deux tests antimicrobiens (Bacillus subtilis et Aliivibrio fischeri). L’adaptation de ces tests s’est accompagnée du criblage de plusieurs espèces du genre Pittosporum. Le troisième volet de ce travail de thèse a porté sur le développement d’un nouveau test en HPTLC-bioautographie. Celui-ci est le fruit d’un partenariat avec l’équipe 6 du C3M de l’Hôpital l’Archet de Nice et porte sur le criblage de composés anti-leishmaniens. En effet les protozoaires n’ont jamais fait l’objet de développements de tests de criblage par HPTLC-bioautographie. Deux tests ont vu le jour, chacun sur une des deux formes du parasite Leishmania infantum : la forme promastigote extracellulaire et la forme amastigote intracellulaire. Ces deux formes ayant des conditions de survie très différentes, les deux tests ont été développés selon deux techniques différentes : la bioautographie directe pour la forme promastigote et la bioautographie par agar overlay pour la forme amastigote
This thesis focuses on the study of a screening method for the bioactivities of natural compounds booming: HPTLC-bioautography. It is a technique combining a chromatographic separation and biological activity tests. The separation of natural compounds from the extract to be tested will be carried out on an HPTLC plate and this same developed plate will be revealed by different methods to test the biological activities of compounds. Generally, there are several categories of tests that can be used: tests antimicrobials, enzyme tests and chemical tests (including research of antioxidants). This work is the result of a partnership (CIFRE) between Université Côte d´Azur and the BotaniCert company, specialized in phytochemical analysis. The request of the BotaniCert company wishing to acquire screening methods activities led to the search for existing HPTLC-bioautography tests and developable in a chemistry laboratory (some antimicrobial tests require the handling of pathogenic organisms and can only be done in laboratories adapted). The choice of certain pathologies resulting from a demand for research and development led to the adaptation to the BotaniCert laboratory of several tests of enzymatic screening (α-glucosidase, acetylcholinesterase, pancreatic lipase) as well as two antimicrobial tests (Bacillus subtilis and Aliivibrio fischeri). The adaptation of these tests is accompanied by the screening of several species of the genus Pittosporum.The third part of this thesis work focused on the development of a new test in HPTLC-bioautography. This is the result of a partnership with team 6 of the C3M in Nice hospital L’ Archet and focuses on the screening of anti-Leishman compounds. This protozoa have never been the subject of developments in screening tests by HPTLC-bioautography. Two tests have emerged, each on one of the two stages of the parasite Leishmania infantum: the extracellular promastigote stage and the intracellular amastigote stage. These two stages having very different survival conditions, the two tests were developed using two different techniques: direct bioautography for promastigote stage and overlay agar bioautography for the amastigote stage