High Throughput Screening for Bioactive Components of Berberis baluchistanica Ahrendt Root and Their Functional Potential Assessment.

Berberis baluchistanica Ahrendt is a medicinal plant potentially known for the treatment of different diseases. The bioactive, antioxidant, nutritional components, and antimicrobial properties of crude ethanolic root extract of Berberis baluchistanica were evaluated in this study. The extract was analyzed for total phenolic, flavonoid, DPPH (2, 2-diphenyl-1-picryl-hydrazyl) scavenging ability, FRAP (ferric reducing antioxidant power), nutritional, and antimicrobial potentials. The alkaloids, tannins, cardiac glycosides, anthraquinones, coumarin, saponins, phenolics, flavonoids, steroids, and terpenoids were confirmed. The extract possessed DPPH radical inhibition with the IC50 of 1.125 mg/mL and FRAP % reduction activity with IC50 (0.912 mg/mL). Total phenolic 19.897 ± 4.8141 mg GAE/g and flavonoid 12.9876 ± 0.8388 mg QE/g contents were confirmed in the root. The extracts exhibit good antibacterial activity against a broad spectrum of food borne pathogens Pseudomonas aeruginosa, Salmonella typhi, Klebsiella pneumoniae, Escherichia coli, and Staphylococcus aureus. The highest inhibitory activity was against Escherichia coli23.30 ± 1.16 mm and lowest against Klebsiella pneumoniae7 ± 0.01 mm. Furthermore, the presence of various phytochemical constituents (plant secondary metabolites) was also confirmed with gas chromatography and mass spectroscopy analysis. Results disclosed the occurrence of more than 70 compounds possessing various medicinal properties supporting the traditional uses of root of Berberis baluchistanica in various medical complications indigenously.

Purification and Characterization of Cellulase from Obligate Halophilic Aspergillus flavus (TISTR 3637) and Its Prospects for Bioethanol Production.

A cellulase from the extreme obligate halophilic fungus, Aspergillus flavus, isolated from a man-made solar saltern in Phetchaburi, Thailand, was purified by ammonium sulfate precipitation and using Sephadex G-100 gel filtration column chromatography. The cellulase was found to be approximately 55 kDa by SDS-PAGE. Using CMC as a substrate, the specific activity of the cellulase was 62.9 units (U) mg-1 with Vmax and Km values of 37.87 mol min-1 mg-1 and 3.02 mg mL-1, respectively. Characterization of the enzyme revealed it to be an extremozyme, having an optimum activity at pH 10, 60 °C, and 200 g L-1 of NaCl. The enzyme activity was not significantly altered by the addition of divalent metal cations at 2 mM and neither did ß-mercaptoethanol, while EDTA was found strongly inhibiting the cellulase. Compared with commercial cellulase, the purified cellulase from A. flavus was more active in the extremity of conditions, especially at pH 10, 60 °C, and 150 g L-1 NaCl, whereas the commercial cellulase had a very low activity.

Biosorption of heavy metals by obligate halophilic fungi.

The presence of heavy metals in the environment poses a serious threat to human health. Remediation of this problem using microorganisms has been widely researched to find a sustainable solution. Obligate halophilic fungi comprising Aspergillus flavus, Aspergillus gracilis, Aspergillus penicillioides (sp. 1), Aspergillus penicillioides (sp. 2), Aspergillus restrictus and Sterigmatomyces halophilus were used for the biosorption of cadmium, copper, ferrous, manganese, lead and zinc. The metals were supplemented as salts in potato dextrose broth for the growth of obligate halophilic fungi and incubated for 14 days. The supernatant and biomass were obtained by the acid digestion method. The biosorption was screened by atomic absorption spectroscopy. All tested fungi showed moderate to high adsorption of heavy metals, amongst which A. flavus and S. halophilus showed the best average adsorption of all heavy metals studied, with an average of 86 and 83%, respectively. On average, Fe and Zn are best removed from the liquid media of obligate halophilic fungi, with an average of 85 and 84%, respectively. This pioneering study of biosorption by obligate halophilic fungi using inexpensive media in stagnant conditions provides a cost-effective environmental solution for the removal of heavy metals.