Purification and anticancer activity of glutaminase and urease-free l-asparaginase from novel endophyte Chaetomium sp.

l-Asparaginase catalyzes the hydrolysis of asparagine into aspartic acid and ammonia. The present work elaborates the isolation and identification of a novel endophytic fungal isolate producing l-glutaminase and urease-free l-asparaginase. Cell growth and enzyme production were investigated for large production. The isolated endophytic fungi were identified at molecular levels and a phylogenetic tree was constructed. The enzyme synthesis was evaluated by cultivating the isolated microorganisms in potato dextrose agar medium. Out of 27 isolated endophytes, nine were producing "l-glutaminase and urease-free l-asparaginase." l-Asparaginase from Chaetomium sp. exhibited superior enzyme activity than from the other isolates. Observed optimal conditions for l-asparaginase activity were 25 min of incubation time, 0.5 mg of enzyme source, 40°C of temperature, and pH 7.0. l-Asparaginase from Chaetomium sp. exhibited anticancer activity on human blood cancer (MOLT-4) cells. The current study has demonstrated the production of contaminant-free l-asparaginase enzyme from endophytic fungal species. The results showed that: (a) maximum enzyme activity was observed for l-asparaginase from Chaetomium sp., (b) concentration of glucose in the medium as a carbon source suppressed the enzyme production. Chaetomium sp. is a novel source for "l-glutaminase and urease-free l-asparaginase," which may play a major role in pharmacotherapy.

Plant extract mediated synthesis enhanced the functional properties of silver ferrite nanoparticles over chemical mediated synthesis.

In this study, the antibacterial, antioxidant and cytotoxicity behaviour of silver ferrite nanoparticles (AgFeO2 NPs) synthesized through chemical and green routes were compared. Green synthesis (Bio) of AgFeO2 NPs were prepared by precipitation method using Amaranthus blitum leaves extract as a reducing agent. Chemical synthesis (Che) of AgFeO2 NPs was mediated by sodium borohydride as a reducing agent. [AgFeO2 (Bio)] NPs showed reduced size, better monodispersity and surface area compared to [AgFeO2 (Che)] NPs. The results showed that synthesized NPs have better antibacterial activity against E. coli than S. aureus. In addition, 250 µg of AgFeO2 (Bio) and (Che) NPs showed antioxidant efficiency of 98 and 86%. The results showed that [AgFeO2 (Bio)] NPs showed lower cytotoxicity [AgFeO2 (Che)] NPs against human human embryonic kidney (HEK 293) cells. These results suggest that [AgFeO2 (Bio)] NPs have improved physicochemical properties thereby they can be used as an effective biocatalytic material in biotechnology.