Enhanced production of laccase and pectinase using co-culture of Trametes hirsuta and Phanerochaete sp. through EVOP-factorial design technique.

The present study deals with the coproduction of laccase and pectinase enzymes through solid state fermentation using mixed fungal culture of Trametes hirsuta and Phanerochaete sp., to minimize the cost and time of the process. Substrates selected for the enzyme production were wheat bran, pulse husk and mustard peel. To get optimum yield of laccase and pectinase in a single fermenter, EVOP factorial design technique with factors like pH, incubation temperature and substrates ratio have been explored. At search level of EVOP, outcomes of the one factor at a time has been considered as incubation temperature 30 °C for 7 days at pH 5 with wheat bran: pulse husk: mustard peel ratio of 2:2:1 (w/w/w) and yield of laccase and pectinase was found as 78.1 U/gds and 105.0 U/gds respectively. In first setup of EVOP factorial both laccase and pectinase activities were not found optimum in same set of experiments; therefore, on the basis of its decision making steps, second set of experiment was performed by taking decisions of first set of EVOP as search level. Optimum yield of laccase and pectinase was achieved about 250 U/gds and 247 U/gds respectively at 34 °C, pH 4.5 with 1.75:1.75:1.5 (w/w/w) wheatbran: pulse husk: mustard peel as substrate, which was 2-3 times higher than the outcomes of one factor at a time method.

Isolation, Screening, and Identification of Novel Isolates of Actinomycetes from India for Antimicrobial Applications.

The search for novel bioactive compounds from the natural environment has rapidly been gaining momentum with the increase in multi-drug resistant (MDR) pathogens. In the present study, the antimicrobial potential of novel actinomycetes has been evaluated by initial screening of six soil samples. Primary and secondary screening was performed against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Candida albicans, Candida tropicalis, Trichophyton rubrum, and other MDR bacterial and fungal test strains, thirteen active isolates were selected for further study. Microbial strains were identified on the basis of growth conditions and other biochemical characters. Five most active microbial strains were identified using 16S rRNA sequence homology and designated as Streptomyces xanthophaeus MTCC 11938, Streptomyces variabilis MTCC 12266, Streptomyces xanthochromogenes MTCC 11937, Streptomyces levis EU 124569, and Streptomyces sp. NCIM 5500. Four antibacterial and three antifungal compounds isolated from the above five isolates were purified and partially characterized using UV absorption and IR spectra. Two antibacterial metabolites, belong to chromone and peptide antibiotic, respectively. The antifungal compounds were found to be of non-polyene nature. In conclusion, we study the isolation of novel bacterial strains of actinomycetes for producing novel compounds having antibacterial and antifungal activities from the unexplored agro-ecological niches of India. Also, this study paves the way for further characterization of these isolates of Streptomyces sp. for their optimum utilization for antimicrobial purposes.