Purification and kinetic behavior of glucose isomerase from Streptomyces lividans RSU26.

Glucose isomerase (GI), an enzyme with deserved high potential in the world market. GI plays a major role in high Fructose Corn Syrup Production (HFCS). HFCS is used as a sweetener in food and pharmaceutical industries. Streptomyces are well-known producers of various industrially valuable enzymes, including Glucose isomerase. Currently, recombinant strains have been available for the production of various enzymes, but it has limitation in the large scale production. Therefore, identifying effective streptomyces strains have emerged. The current study, the novel S. lividans RSU26 was isolated from a marine source and optimized its potential to produce glucose isomerase at different physical and chemical conditions. The optimum pH and temperature for GI and biomass production were 7.5 and 35 °C, respectively at 96 h. Characterization study revealed that the approximate molar mass of GI was 43 kDa for monomeric and 170 kDa for tetrameric forms. Kinetic behavior exhibits Km, and Vmax values for the conversion of fructose to glucose conversion were 48.8 mM and 2.54 U mg-1 at 50 °C and glucose to fructose were 29.4 mM and 2.38 U mg-1 at 65 °C protein, respectively. Therefore, the present study suggested that the wild-type S. lividans RSU26 has strong potential to produce glucose isomerase for various industrial applications.

Production of lactic acid using a new homofermentative Enterococcus faecalis isolate.

Lactic acid is an intermediate-volume specialty chemical for a wide range of food and industrial applications such as pharmaceuticals, cosmetics and chemical syntheses. Although lactic acid production has been well documented, improved production parameters that lead to reduced production costs are always of interest in industrial developments. In this study, we describe the production of lactic acid at high concentration, yield and volumetric productivity utilizing a novel homofermentative, facultative anaerobe Enterococcus faecalis CBRD01. The highest concentration of 182 g lactic acid l(-1) was achieved after 38 h of fed-batch fermentation on glucose. The bacterial isolate utilized only 2-13% of carbon for its growth and energy metabolism, while 87-98% of carbon was converted to lactic acid at an overall volumetric productivity of 5 g l(-1) h(-1). At 13 h of fermentation, the volumetric productivity of lactate production reached 10.3 g l(-1) h(-1), which is the highest ever reported for microbial production of lactic acid. The lactic acid produced was of high purity as formation of other metabolites was less than 0.1%. The present investigation demonstrates a new opportunity for enhanced production of lactic acid with potential for reduced purification costs.

Synthesis, characterisation and evaluation of N-mannich bases of 2-substituted Benzimidazole derivatives.

RATIONALE: Benzimidazoles and its derivatives represent one of the mainly biological active classes of literature. AIM: In this present study aimed to synthesize N-mannich bases derivatives compounds bearing of 2-substituted benzimidazole moiety, in order to investigate their possible biological activity. METHOD: Benzimidazole compounds were prepared from the condensation reaction between ortho phenylene diamine and various acids. Mannich base of newly synthesized Benzimidazole derivatives were synthesized from 2-substituted Benzimidazoles by reacting with secondary amines. The purity of the compounds was ascertained by melting point (m.p) and thin layer chromatography (TLC). Structures of the synthesized compounds were elucidated by spectral data. Antimicrobial assay was performed by microbroth dilution method. Bacterial genomic DNA cleavage was assessed by Agarose gel electrophoresis. Toxicity of the most effective compounds was studied by Brine-shrimp lethality assay. RESULT: Among the synthesized compounds, compound 5E (a) and (b) was establish to be the most potent against all tested microorganisms. This two compounds exhibited complete bacterial DNA cleavage and non-toxic. CONCLUSION: These results suggest that it an interesting compound compared to the current therapeutic agents and are considered to investigate further for the same.