A Green Process for Starch Oleate Synthesis by Cryptococcus sp. MTCC 5455 Lipase and Its Potential as an Emulsifying Agent

Starch oleate is synthesized in an aqueous medium using lipase from the yeast Cryptococcus sp. MTCC 5455. The optimum conditions of esterification are found at 24 h and 30 �C with an oleic acid/starch molar ratio of 1:2 using 500U of lipase and the degree of substitution was 0.26. Spectral techniques confirm the presence of oleate group in the modified potato starch. Scanning electron microscopic and X-ray diffraction studies also reveal the morphological and crystallographic properties of starch which are disrupted during the esterification process. Thermogravimetric analysis indicates the decrease in thermal stability of starch oleate due to the transformed structure of starch from semi crystalline to an amorphous form. The synthesized starch oleate could impart 85% stability to emulsions and has potential as an emulsifier in food sector owing to its eco-friendly preparation

<span style="font-size:11.0pt;mso-bidi-font-size: 12.0pt;font-family:"Times New Roman","serif";mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:Mangal;mso-ansi-language:EN-GB;mso-fareast-language:EN-US; mso-bidi-language:HI" lang="EN-GB">Production of α-galactosidase from <i style="mso-bidi-font-style: normal">Aspergillus foetidus</i> MTCC 6322 by solid state fermentation and its application in soymilk hydrolysis</span>

72-75<span style="font-size:11.0pt;mso-bidi-font-size: 12.0pt;font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" mso-bidi-font-family:mangal;mso-ansi-language:en-gb;mso-fareast-language:en-us;="" mso-bidi-language:hi"="" lang="EN-GB">The production of α-galactosidase from the wild fungal strain Aspergillus foetidus MTCC 6322 using solid state fermentation (SSF), its characterization, and its efficacy in the hydrolysis of soymilk using response surface methodology were studied. The optimum conditions for production of α-galactosidase by SSF were: wheat bran (10 g), moisture content (64%), inoculum volume (1.0 mL; 6 × 107 spores/mL) with a yield of 4.1 × 103 units per gram dry substrate (U/gds) at 96 h. The enzyme showed optimum activity at pH 6.0, temperature 40°C, pH stability between 5.0-8.0, and temperature stability between 30-40°C. The enzyme was stable in the presence of trypsin, lipase, and collagenase and it showed susceptibility of the substrates such as raffinose, melibiose, guar gum and soymilk to hydrolysis in varying degrees. The optimized conditions for soymilk hydrolysis were: soymilk (10 mL) from defatted soybean meal (1.5%), α-galactosidase (0.15 UmL-1) at 30°C, pH 6.0 and duration of 1 h.</span

Cutinase-Like Enzyme from the Yeast Cryptococcus sp. Strain S-2 Hydrolyzes Polylactic Acid and Other Biodegradable Plastics

A purified lipase from the yeast Cryptococcus sp. strain S-2 exhibited remote homology to proteins belonging to the cutinase family rather than to lipases. This enzyme could effectively degrade the high-molecular-weight compound polylactic acid, as well as other biodegradable plastics, including polybutylene succinate, poly (ɛ-caprolactone), and poly(3-hydroxybutyrate)

Statistical medium optimization of an alkaline protease from <i style="mso-bidi-font-style: normal">Pseudomonas aeruginosa </i>MTCC 10501, its characterization and application in leather processing

336-342Proteases are shown to have greener mode of application in leather processing for dehairing of goat skins and cow hides. Production of protease by submerged fermentation with potent activity is reported using a new isolate P. aeruginosa MTCC 10501. The production parameters were optimized by statistical methods such as Plackett-Burman and response surface methodology. The optimized production medium contained (g/L); tryptone, 2.5; yeast extract, 3.0; skim milk 30.0; dextrose 1.0; inoculum concentration 4%: initial pH 6.0; incubation temperature 30 °C and optimum production at 48 h with protease activity of 7.6 U/mL. The protease had the following characteristics: <i style="mso-bidi-font-style: normal">pH optima, 9.0; temperature optima 50 °C; <i style="mso-bidi-font-style: normal">pH stability between 5.0-10.0 and temperature stability between 10-40 °C. The protease was observed to have high potential for dehairing of goat skins in the pre- tanning process comparable to that of the chemical process as evidenced by histology. The method offers cleaner processing using enzyme only instead of toxic chemicals in the pre-tanning process of leather manufacture

Growth associated degradation of aliphatic-aromatic copolyesters by Cryptococcus sp. MTCC 5455

The degradation of aliphatic-aromatic copolyesters, poly[(butylene succinate/terephthalate/isophthalate)- co-(lactate)] (PBSTIL) and poly(butylene adipate co-terephthalate) (PBAT) under mesophilic conditions was investigated using the yeast, Cryptococcus sp. MTCC 5455. Complete degradation of PBSTIL and PBAT films was observed at 25 �C within 96 and 216 h, respectively. Lipase was produced during the course of degradation and the encoding gene was expressed in Escherichia coli BL21 (DE3). The production of lipase was enhanced by cumulative induction with 0.1mM IPTG and 1.5mM lactose for 24 h at 25 �C, which resulted in a maximum lipase activity of 27.75 ± 1.0 U/mL. Spectral studies of the degraded polymeric films confirmed the hydrolysis of ester bonds by the lipase. Scanning electron microscopy revealed the formation of cracks and holes on the surface of the polymeric films during degradation. The results indicated the feasibility of the process towards degradation of polymeric waste at ambient temperatures within a short period of time