Purification, catalytic, kinetic, thermodynamic characterization and stability profile of alkalophilic lipase from Streptomyces sp. SBLWN_MH2

Accessing the biotechnological potential of a novel isolated microalga from a semi-arid region of Brazil

The use of microalgae as a source of food and pharmaceutical ingredients has garnered growing interest in recent years. Despite the rapid growth of the nutraceutical market, knowledge about the potential of bioactive molecules from microalgae remains insufficient. The present study aimed to investigate the biotechnological potential of the green microalga Desmodesmus armatus isolated from a semi-arid region of Brazil. The algal biomass was characterized in terms of gross biochemical composition, exopolysaccharide content, enzymatic inhibition capacity, and antioxidant, antibacterial, and hemolytic activities from solvents of different polarities (water, ethanol, acetone, and hexane). D armatus biomass had 40% of crude protein content, 25.94% of lipids, and 25.03% of carbohydrates. The prebiotic potential of exopolysaccharides from D armatus was demonstrated, which stimulated the growth of Lacticaseibacillus rhamnosus and Lactiplantibacillus plantarum bacteria strains. Moreover, the enzyme inhibition capacity for the proteases chymotrypsin (34.78%-45.8%) and pepsin (16.64%-27.27%), in addition to α-amylase (24.79%) and lipase (31.05%) was confirmed. The antioxidant potential varied between the different extracts, with 2,2-diphenyl-1-picrylhydrazyl sequestration values varying between 17.51% and 63.12%, and those of the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) method between 6.82% and 22.89%. In the antibacterial activity test, only the ethanolic extract showed inhibition against Listeria sp. (at minimum inhibitory concentration [MIC] = 256 µg mL-1). This fraction also presented the highest significant levels of hemolysis (31.88%-52.45%). In summary, the data presented in the study suggest the presence of biocompounds with biotechnological and nutraceutical potential in the D armatus biomass. Future studies may evaluate the inclusion of this biomass in foods in order to increase their biological value.

Characterization of Detergent-Compatible Lipases from Candida albicans and Acremonium sclerotigenum under Solid-State Fermentation

The purpose of this study was to compare and explore the potential of two distinct lipases at industrial levels after their production using wheat bran substrate in solid-state fermentation. Lipases from Candida albicans (C. albicans) and Acremonium sclerotigenum (A. sclerotigenum) were characterized to assess their compatibility and suitability for use in laundry detergents. The effects of pH, temperature, metal ions, inhibitors, organic solvents, and various commercially available detergents on these lipases were studied in order to compare their activity and stability profiles and check their stain removal ability. Both lipases remained stable across the wide pH (7-10) and temperature (30-50 °C) ranges. C. albicans lipase exhibited optimum activity (51.66 U/mL) at pH 7.0 and 37 °C, while A. sclerotigenum lipase showed optimum activity (52.12 U/mL) at pH 8.0 and 40 °C. The addition of Ca2+ and Mg2+ ions enhanced their activities, while sodium dodecyl sulfate (SDS) and ethylenediamine tetraacetic acid (EDTA) reduced their activities. Lipase from both strains showed tolerance to various organic solvents and considerable stability and compatibility with commercially available laundry detergents (>50%); however, A. sclerotigenum lipase performed slightly better. Characterization of these crude lipases showed nearly 60% relative activity after incubation for 2 h in various detergents, thus suggesting their potential to be employed in the formulation of laundry detergents with easy and efficient enzyme production. The production of thermostable and alkaline lipases from both strains makes them an attractive option for economic gain by lowering the amount of detergent to be used, thus reducing the chemical burden on the environment.