Species of Lactobacillus are widely used as starter cultures in the dairy industry and have been reported to play a significant role in the production of bioactive peptides in fermented dairy products. The aim of the present study was to screen selected strains of Lactobacillus for their ability to generate antioxidant activity during the fermentation of milk and to correlate their proteolytic activity with antioxidative peptide production. Skim milk fermented with 19 strains of Lactobacillus from ten species was evaluated for antioxidant activity by 2, 2′-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) decolourization assay. The whey fraction of fermented skim milk showed radical scavenging activity ranging from 0.12 to 0.49 mmol·L −1 Trolox equivalent antioxidant capacity. The proteolytic activity of the different strains ranged from 0.40 to 2.25 mmol·Leu·L −1 . Seven strains including Lactobacillus delbrueckii subsp. bulgaricus NCDC08, Lactobacillus plantarum NCDC25, Lactobacillus casei subsp. casei NCDC17, Lactobacillus rhamnosus NCDC24, Lactobacillus paracasei subsp. paracasei NCDC63, Lactobacillus fermentum NCDC141 and Lactobacillus helveticus NCDC288 exhibited a positive correlation between antioxidant and proteolytic activity. On hydrolysis of casein with cell-free extract from these seven strains, L. rhamnosus NCDC24, L. casei subsp. casei NCDC17 and L. paracasei subsp. paracasei NCDC63 showed a significant (P<0.05) increase in radical scavenging activity. The low molecular weight peptides (<3 kg·mol −1 ) represented 60-70% of the total radical scavenging activity for these three strains. The development of antioxidant activity was found to be strain specific and that these strains of

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In the present study, the fruiting body extracts of Xylaria sp. strain R006 were obtained from hexane, ethyl acetate and methanol. Among them, the ethyl acetate extract exhibited significant antimicrobial activities against bacterial and fungal pathogens. Based on the effective antimicrobial activity, the crude ethyl acetate extract was fractionized by two-step siliga gel column chromatography. All the fractions were tested for antibacterial activity against drug resistant Staphylococcus aureus strains (1-10) and Pseudomonas aeruginosa strains (1-8). The fraction E showed a maximum inhibition zone of 27.9 mm against drug resistant S. aureus strain 3 and 29.4 mm against drug resistant P. aeruginosa strain 4. Minimal inhibitory concentration of fraction E showed potential result against all the drug resistant strains however, the lowest concentration of 75 µg/mL-1 was observed against S. aureus strains 1 and 6 and P. aeruginosa strain 3. Further, 60 µg/mL of fraction E had significant cytotoxic activity of 54.9, 55.1 and 54.9% against MDA-MB-231 (breast carcinoma cells), A-549 (lung carcinoma cells) and MCF-7 (breast carcinoma cells) human cancer cell lines, respectively. The spectral data revealed that the fraction E has chromophoric groups in it and had the C = O stretching, C-C = C asymmetric stretch, N-H stretch and C-O stretch as functional groups. The results indicate that the metabolites of fruiting bodies of Xylaria sp. R006 are the potential natural source for the development of new anticancer agents.

Enormous fungal species live within the healthy plant tissues, some of which presumably occur in a symbiotic association with host. Some fungal endophytes are widespread and can be found in many different plant species, whereas others are highly specific to single hosts. In this study, we isolated three endophytic fungi from the medicinal plant Vitex negundo. They were identified based on morphological characteristics such as size, shape, and colour of the spore and it was reinforced by 18s rRNA gene sequence analysis. The phylogenetic tree showed that C. gloeosporioides VN1 and Pestalotiopsis virgatula VN2 were closely relationship between. But they were not closely relationship between the other endophytic fungal species that were obtained from geographically different part of the world. This aspect can be further explored to understand the relationships between plant hosts and their fungal endophyte.

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