There is a growing body of evidence that endophytic fungal metabolites possess important biological activities. Cynodon dactylon (L.) Pers., a well-known grass species with potential medicinal properties, is under-explored for the diversity of endophytic fungal species and their metabolites. We report here the diversity of endophytic fungi in the culm, leaf and inflorescence of Cynodon dactylon when cultured on moist blotter (MB), potato dextrose agar (PDA) and malt extract agar (MEA). Species richness, Shannon and Simpson diversity and evenness indices showed that PDA followed by MEA supported the growth of the largest number of fungal species. Amongst four fungal species tested, Curvularia tsudae was selected for further studies on antimicrobial and antioxidant activities. The mycelial mat (MM) and culture filtrate (CF) of PD broth grown Curvularia tsudae extracted with ethyl acetate and methanol, respectively, were subjected to antimicrobial assay against five bacterial and four fungal test isolates. Results indicated that the ethyl acetate extract of CF had moderate activity against Enterococcus faecalis, Escherichia coli, Pseudomonas fluorescence and Staphylococcus aureus whereas the methanolic MM extract showed high to moderate activity to Aspergillus flavus, A.  https://www.selleckchem.com/ALK.html  niger and Fusarium oxysporum. Cyclic voltammetric analysis of ethyl acetate extract showed very good antioxidant activity and the extract contained coumarins when determined by HPLC. High-resolution orbitrap LC-MS of ethyl acetate extract revealed the presence of metabolites with antimicrobial and antioxidant and other biological activities. Finding of the present study suggested that Curvularia tsudae could be exploited for pharmaceutical applications.Photorhabdus akhurstii is an insect-parasitic bacterium that symbiotically associates with the nematode, Heterorhabditis indica. The bacterium possesses several pathogenicity islands that aids in conferring toxicity to different insects. Herein, we constructed the plasmid clones of coding sequences of four toxin genes (pirA, tcaA, tccA and tccC; each was isolated from four P. akhurstii strains IARI-SGMG3, IARI-SGGJ2, IARI-SGHR2 and IARI-SGMS1) in Escherichia coli and subsequently, their biological activity were investigated against the fourth-instar larvae of the model insect, Galleria mellonella via intra-hemocoel injection. Bioinformatics analyses indicated inter-strain amino acid sequence difference at several positions of the candidate toxins. In corroboration, differential insecticidal activity of the identical toxin protein (PirA, TcaA, TccA and TccC conferred 15-59, 27-100, 25-100 and 33-98% insect mortality, respectively, across the strains) derived from the different bacterial strains was observed, suggesting that the diverse gene pool in Indian strains of P. akhurstii leads to strain-specific virulence in this bacterium. These toxin candidates appear to be an attractive option to deploy them in biopesticide development for managing the insect pests globally.The addition of n-dodecane (between 1-3%) to the Escherichia coli fermentation broth in a mechanically agitated and aerated bioreactor revealed improved DO (dissolved oxygen) levels induced during fermentation which lead to an increase in biomass productivity and faster glucose consumption. The maximum values for enzyme activity (increased with 43% compared with the control) and k L a (the volumetric mass transfer coefficient) were obtained for the addition of 2% v/v n-dodecane in the bioreactor, due to the fact that oxygen limitation during the exponential growth phase of the bacterium can repress β-galactosidase production. The oxygen vector addition increased the available dissolved oxygen and activated a redox-sensitive regulation and an elevated intracellular oxidative metabolism that lead to the enhancement in E. coli biomass accumulation and a more accurate protein folding of β-galactosidase that would increase its activity. In addition to the experimental analysis, a complex model, developed using an improved version of Bacterial Foraging Algorithm and Artificial Neural Networks, was proposed, with a good average absolute value (6.2% in the training phase and 7.28% in the testing phase) between the process dynamic and the predictions generated by the model.In this study, the lipopeptide biosurfactant was extracted, purified and characterized from the Bacillus isolate LK5.4 obtained from kinema samples of Sikkim. Plant growth-promoting property of the biosurfactant producing bacterium was also evaluated. Out of fifty-seven isolates, only ten were biosurfactant producer as determined by the oil displacement test. Bacillus isolate LK5.4 showed the maximum emulsification index (52.3 ± 0.02), reduced surface tension up to 40% and produced 754 mgL-1 biosurfactant in the nutrient broth. Based on 16S rRNA gene sequencing, the isolate LK5.4 was identified as B. tequilensis. Biosurfactant was purified by Thin Layer Chromatography (TLC). Evaluation of the chemical characteristics by TLC, Liquid Chromatography-Mass Spectrometry, Fourier Transform Infrared Spectroscopy and Nuclear Magnetic Resonance Spectroscopy identified the biosurfactant as surfactin. The effect of different concentration of biosurfactant in maize seed germination was evaluated under in vitro condition. It showed the fastest growth of seedlings at 300 µg/ml biosurfactant solution. Similar results were shown by the potted plant experiment, where the soil was directly treated with biosurfactant producing bacterium LK5.4. The LK5.4 treated plants showed a mean height of 29.17 ± 0.47 cm and mean leaf length of 18.42 ± 0.17 cm while the mean height and mean length of the leaf were 15.48 ± 0.98 cm and 11.12 ± 0.40 cm respectively in the control plants. The treated plants had higher moisture content (68.48 ± 2.79%) than the control plants (50.53 ± 1.63%), which is because of higher bioadsorption in the treated plants. These results provided indirect evidence of plant growth-promoting property of the biosurfactant.Ingested dietary fibres are hydrolysed by colon microbiota to produce energy-providing short-chain fatty acids (SCFA) that stimulate anti-inflammatory effects. SCFA-producing bacteria were screened from bacteria isolated from human faeces using bromothymol blue as an acid indicator and gas chromatography for SCFA profiling. The beneficial functions (antagonistic activity, haemolytic activities, antibiotic susceptibility, mucus adherent percentage and toxin gene detection) were evaluated for the top five SCFA-producing bacteria isolated from three healthy volunteers that identified as Escherichia coli strains. They produced acetic, propionic, isobutyric, butyric, isovaleric, valeric and caproic acids at average concentrations of 15.9, 1.8, 1.1, 1.9, 1.8, 2.7 and 3.4 mM, respectively. The SCFA production by E. coli strains was rapidly increased during the first 8 h of incubation and gradually decreased after 16 h of incubation. All E. coli strains showed acid and bile tolerance, resulting in a survival rate greater than 70% with no haemolytic activity, mucus adherence greater than 40% and susceptibility to conventional antibiotics.