ANTIOXIDATIVE AND ANTIBACTERIAL POTENTIALS OF FUNGAL ENDOPHYTES FROM JUSTICIA WYNAADENSIS HEYNE: AN ETHNOMEDICINAL RAIN FOREST SPECIES OF WESTERN GHATS

Objective: Endophytes, living within the medicinal plants, are recognized as an alternative source of bioactive components useful for human health. This study aims to isolate and identify the fungal endophytes from the ethnomedicinal rain forest plant Justicia wynaadensis and evaluation of their antioxidant and antimicrobial potentials. Methods: Endophytic fungi were isolated and identified by sequencing the internal transcribed spacer. The secondary metabolites were extracted with ethyl acetate and evaluated for the total phenolic, flavonoid, antioxidant, and antibacterial potentials. The antioxidative capacities were determined using different experimental models, viz., radical scavenging capacity, reducing power, and inhibition of lipid peroxidation. The antibacterial potential of extracts was determined through disc diffusion method and by evaluating minimum inhibitory concentration through microplate technique. Results: A total of nine fungal endophytes belonging to six genera were identified. The total phenolic content of the extracts ranged from 4.8±0.08 to 20.74±0.96 mg Gallic acid equivalent/g dry extract. Flavonoid was present in eight extracts in the range of 2.1±0.08 to 8.75±0.6 mg catechin equivalent/g dry extract. Fusarium incarnatum was found to have potentially high antioxidant capacity as well as broad spectrum antibacterial activity against Gram-positive and Gram-negative bacteria. Conclusion: This study reported various endophytic fungi from the plant J. wynaadensis. This is the first attempt to explore the treasure of endophytes and their bioactive potentiality from this plant. Hence, our findings encourage the exploration of these fungi and exploit them in search of potential drug discovery

Endophytic Fungal Diversity in Medicinal Plants of Western Ghats, India

Endophytes constitute an important component of microbial diversity, and in the present investigation, seven plant species with rich ethnobotanical uses representing six families were analyzed for the presence of endophytic fungi from their natural habitats during monsoon (May/June) and winter (November/December) seasons of 2007. Fungal endophytes were isolated from healthy plant parts such as stem, root, rhizome, and inflorescence employing standard isolation methods. One thousand five hundred and twenty-nine fungal isolates were obtained from 5200 fragments. Stem fragments harbored more endophytes (80.37%) than roots (19.22%). 31 fungal taxa comprised of coelomycetes (65%), hyphomycetes (32%), and ascomycetes (3%). Fusarium, Acremonium, Colletotrichum, Chaetomium, Myrothecium, Phomopsis, and Pestalotiopsis spp. were commonly isolated. Diversity indices differed significantly between the seasons (P<0.001). Species richness was greater for monsoon isolations than winter. Host specificity was observed for few fungal endophytes. UPGMA cluster analysis grouped the endophytes into distinct clusters on the basis of genetic distance. This study is the first report on the diversity and host-specificity of endophytic fungal taxa were from the semi evergreen forest type in Talacauvery subcluster of Western Ghats

Green Synthesis of Gold Nanoparticles from Vitex negundo Leaf Extract to Inhibit Lipopolysaccharide-Induced Inflammation Through In Vitro and In Vivo

Gold nanoparticles (AuNPs) have wide applications in the field of diagnosis and treatment of diseases which are attributed to their compatibility and high efficiency of drug delivery, because of their eco-friendly nature and easy handling. In the current study, we have used an extract of Vitex negundo, a traditional anti-inflammatory folk medicine in India and synthesized gold nanoparticles (VnAuNPs), to know the effects of anti-bacterial, antioxidant, and anti-inflammatory properties both in vivo and in vitro. V. negundo leaf extracts (VnLE) per se yielded high flavonoids, saponins, tannins, alkaloids, glycosides, phenols, terpenoids. The synthesized VnAuNPs in leaf extracts was confirmed by UV-vis spectra at 543 nm and further by Fourier transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM) and through Dynamic light scattering (DLS). The FTIR showed the peaks at 3345, 1638, 692, 683, 662 cm(-1) which are responsible for the reduction and capping of gold nanoparticles. The size and shape of the AuNPs were determined by SEM. DLS study analysed the particle size distribution of AuNPs. The VnAuNPs showed significant antibacterial activity on both gram positive and negative bacteria. VnAuNPs also showed strong antioxidant (DPPH, H2O2 scavenging, Nitric oxide scavenging power and reducing power) activities when compared to VnLE extract. The VnAuNPs exhibited strong anti-inflammatory activities (COX-2, lipoxygenase and xanthine oxidase inhibitory activity) in in vitro (HeLa cell model) and in vivo study of carrageenan induced paw edema model in Swiss albino mice (paw edema and acetic acid-induced writhing test). Results suggested that the synthesized VnAuNPs are potential candidates for treating inflammatory diseases and may find application in clinical studies

Elicitation of Novel Trichogenic-Lipid Nanoemulsion Signaling Resistance Against Pearl Millet Downy Mildew Disease

Nanoemulsion was formulated from membrane lipids of Trichoderma spp. with the non-ionic surfactant Tween 80 by the ultrasonic emulsification method. Nanoemulsion with a droplet diameter of 5 to 51 nm was obtained. The possible effects of membrane lipid nanoemulsion on pearl millet (PM) seed growth parameters and elicitation of downy mildew (DM) disease resistance in PM was analyzed to develop an eco-friendly disease management strategy. Seed priming with nanoemulsion illustrates significant protection and elevated levels of early defense gene expression. Lipid profiling of Trichoderma spp. reveals the presence of oleic acid as a major fatty acid molecule. The prominent molecule in the purified lipid fraction of T. brevicompactum (UP-91) responsible for the elicitation of induction of systemic resistance in PM host against DM pathogen was predicted as (E)-N-(1, 3-dihydroxyoctadec-4-en-2yl) acetamide. The results suggest that protection offered by the novel nanoemulsion formulation is systemic in nature and durable and offers a newer sustainable approach to manage biotrophic oomycetous pathogen