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Aspergillus terreus NCFT4269.10 was implemented in solid-state (SSF) and liquid static surface fermentation (LSSF) for biosynthesis of pectinase. Amongst various substrates, like, mustard oil cake, neem oil cake, groundnut oil cake, black gram peels, green gram peels, chickling vetch peels/grass pea peels wheat bran, pearl millet residues, finger millet waste, broken rice, banana peels (BP), apple pomace (AP) and orange peels, banana peel (Musa paradisiaca L.; Family: Musaceae) was most suitable for pectinase biosynthesis (LSSF: 400 ± 21.45 Uml−1; SSF: 6500 ± 1116.21 Ug−1). Optimization of process parameters using one-variable-at-a-time method revealed that an initial medium pH of 5.0 at 30 °C and 96 h of incubation along with mannitol, urea, ammonium persulfate and isoleucine have positive influence on pectinase production. Further, K+ (1 mM), Riboflavin (10 mg 100 ml−1) and gibberellic acid (0.025 %, w/v) supported in enhanced pectinase production. Banana peels and AP at a ratio of 9:1, moisture content of 90 % with 2 % inoculum size were suitable combinations for production of pectinase. Similarly, 96 h of soaking time with 0.1 M phosphate buffer (pH 6.5) is essential for pectinase recovery. Purification to electrophoretic homogeneity revealed 1.42 fold purification with 8.08 % yield and a molecular weight of 24.6 kDa. Scaling up of various fermentation parameters and supplementing BP as the substrate for pectinase production with better recovery could make it promising for different industrial exploitation.

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Enzyme production by Aspergillus terreus NCFT 4269.10 was studied under liquid static surface and solid-state fermentation using mustard oil cake as a substrate. The maximum lipase biosynthesis was observed after incubation at 30 °C for 96 h. Among the domestic oils tested, the maximum lipase biosynthesis was achieved using palm oil. The crude lipase was purified 2.56-fold to electrophoretic homogeneity, with a yield of 8.44%, and the protein had a molecular weight of 46.3 kDa as determined by SDS-PAGE. Enzyme characterization confirmed that the purified lipase was most active at pH 6.0, temperature of 50 °C, and substrate concentration of 1.5%. The enzyme was thermostable at 60 °C for 1 h, and the optimum enzyme–substrate reaction time was 30 min. Sodium dodecyl sulfate and commercial detergents did not significantly affect lipase activity during 30-min incubation at 30 °C. Among the metal ions tested, the maximum lipase activity was attained in the presence of Zn2+, followed by Mg2+ and Fe2+. Lipase activity was not significantly affected in the presence of ethylenediaminetetraacetic acid, sodium lauryl sulfate and Triton X-100. Phenylmethylsulfonyl fluoride (1 mM) and the reducing, β-mercaptoethanol significantly inhibited lipase activity. The remarkable stability in the presence of detergents, additives, inhibitors and metal ions makes this lipase unique and a potential candidate for significant biotechnological exploitation.

ABSTRACT:The demand for biodegradable polymers produced from renewable natural resources continues to grow as environmental concerns increase. Biodegradable plastics derived from agricultural feedstock are a new generation of materials capable of reducing the environmental impact in terms of energy consumption and greenhouse effect in specific applications to perform as traditional/ conventional plastics when in use and are completely biodegradable within a composting cycle through the action of living/micro-organisms. The objective of this study is to examine the potentiality and performance pattern of soy protein isolate (SPI) resin, modified with various concentrations of thiosemicarbazide (TSC), as a thermoplastic to substitute some conventional petroleum-based plastics. The spectral, thermal, morphological properties and the biodegradability of the modified resin have been investigated. The spectral studies indicate that TSC is not crosslinked with the protein moiety; rather, it acts as a modifier. Thermogravimetric analysis of the modified material has been followed using a computer analysis method (LOTUS package) developed by us for assigning the degradation mechanism. A number of equations have been used to evaluate the kinetic parameters. The degradation mechanism has been ascertained on the basis of the kinetic parameters. It is expected that, this environment-friendly, fully biodegradable and sustainable TSC-modified SPI green plastic could be commercially used for making molded products.