Aqueous and ethanolic extracts of leafy stems of Acacia hockii harvested in Tanguiéta, were examined for antimicrobial and antioxidant activities. Phytochemical screening of A. hockii was performed using two complementary methods: tube test and thin layer chromatography method. Antimicrobial activities of aqueous and ethanolic extracts were investigated against four Gram Positive and two Gram negative strains bacteria and three species of Aspergillus. The microdilution and agar diffusion methods were used to evaluate antibacterial and antifungal activities respectively. The antioxidant activity was evaluated by 2,2-diphenyl-1-picryl-hydrazyl (DPPH) method. The results showed the presence of Alkaloids, flavonoids, anthracene derivatives, tannins, pigments, triterpenes, saponins and lignans in aqueous and ethanolic extracts of A. hockii leafy stems. Coumarins are only present in the ethanolic extract. The minimum inhibitory concentrations of extracts ranged from 0.625 mg/ml to 5 mg/ml. Both extracts showed significant inhibition effect of sporulation with an inhibitory percentage up to 95.88%, while little to moderate inhibition was obtained against the mycelium growth (36.62 to 78.80 %). Antioxidant activity of extracts ranged from 6 to 96 %. The results suggested that Acacia hockii extracts contains antimicrobial and antioxidant agents.
In present study, purification and characterization of two alpha-glucosidases from termite workers Macrotermes bellicosus (Termitidae: Macrotermitinae) were conducted. The purification procedure consisted of anion-exchange, gel filtration, and hydrophobic interaction chromatography. The enzymes designated alpha-glucosidases A1 and A2 had native molecular weights of approximately 191.23± 0.7 and 140.39± 1.2 kDa, respectively, and there functioned as monomeric structures. The two isoforms isolated exhibited maximal alpha-glucosidase activity pH at 5.6. Alpha-glucosidases A1 and A2 hydrolytic activities were maximal at 50 and 45°C, respectively. The purified enzymes pH stabilities were in the range of 5.0-6.0. The enzymes readily hydrolyzed p-nitrophenyl-α-D-glucoside, maltose, maltodextrins and required strictly alpha-gluco configuration for activity. They cleaved glucose-glucose alpha-(1–2) linkages better than alpha-(1–4), alpha-(1–1), alpha-(1–3) and β-(1–6) linkages. The catalytic efficiency (Vmax/ KM) values for p-nitrophenyl-α-D-glucoside, were respectively 277.75±9.2 and 59.51±4, for alpha-glucosidases A1 and A2. Both alpha-glucosidases were inhibited by sulfhydryl-binding reagents. The physiological role of the two alpha-glucosidases in the digestive tract of the termite could be the digestion of di-and oligosaccharides derived from starch. The enzymes could be used as a tool in the structural analysis of D-glucose containing oligosaccharide chains of glycoproteins, glycolipids and starch.
Aristolochia indica is a popular medicinal plant in the Ayurvedic Pharmacopeia of India. Plant is collected from the wild for its medicinal usage, in the present study medicinal potential of cultivated medicinal plant under standard conditions was explored. Phytochemical analysis revealed presence of flavonoids and tannins like important class of compounds, where as leaf extracts of the plant showed cytotoxic as well as antioxidant potential using brine shrimp mortality and DPPH radical scavenging assays. Acetone extract of the plant showed best cytotoxic and antioxidant potential amongst all the extracts.