Purification and characterization of xylanase from Aspergillus fumigatus isolated from soil

The objectives of the present study were to purify and characterize xylanase enzyme from the fungus obtained from soil. A total of 40 fungi were isolated from 25 soil samples collected after primary screening on Potato Dextrose Agar. In the secondary screening (malt extract agar, 0.5% birch wood xylan), based on the diameter of the clear zone, the fungus was identified as Aspergillus fumigatus by microbial type culture collection (MTCC), Chandigarh, India and was selected for xylanase enzyme production in solid state fermentation using wheat bran. Xylanase was subjected to a three-step purification scheme involving ammonium sulphate precipitation, gel filtration chromatography and anion exchange chromatography. Purity was verified by running the extracted protein on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and a single band was observed. When compared with the standard wide range protein molecular markers on SDS-PAGE, it was found to have a molecular weight of 43 KDa. The Km and Vmax value of xylanase was 3.12 mg/ml and 2857 μmol/min/mg protein as obtained from a Lineweaver-Burk plot. The optimal temperature and pH was found to be 30 and 10°C, respectively. After 4 h of incubation, enzyme retained 100% activity at 30°C. Xylanase was incubated at various pH levels (2 to 12) for 4 h at 30°C, and the residual activity was measured. More than 65% of the original activity was retained at pH ranging from 4 to 10 after 4 h.Keywords: Xylanase, Aspergillus fumigatus, production, enzyme purification, enzyme characterization, Lineweaver–Burk plotAfrican Journal of Biotechnology Vol. 12(20), pp. 3049-305

Antimicrobial activity in leaf, seed extract and seed oil of Jatropha curcas L. plant

The study on antibacterial and antifungal efficacy of leaf and seed extract and seed oil of Jatropha curcas reveals that the inhibition zones ranged from 7 to 22 mm for antibacterial and from 10 to 20 mm for antifungal activity. Among all extracts tested, seed extract showed significant activity while leaf extract showed intermediate activity against gram-positive bacteria. In case of gram-negative bacteria, seed extract and seed oil has shown some moderate activity whereas, no activity was observed in leaf extract. In case of fungal cultures, among all test extracts only seed extract showed significant activity against Mucor and Tilletia fungus, while in case of Rhizopus no activity was observed against all test extracts. These results indicated the possibility of using Jatropha extract and seed oil for medicinal uses and natural food preservation

Occurrence of Pollinator Bees in Leh: Ladakh (Jammu & Kashmir) at 3430 Metres (11,200 feet) Altitude in India

OUT OF 19,000 species of wild bee in the world (Linsley, 1958) only two, the leaf-cutting bee Megachile rotunda Fabr. (Bohrat, 1972; Johanson & Mayer, 1976) and the Alkali Bee Nomia mela11deri Cockerell (Johanson & Eves, 1973) are manipulated and used in crop pollination

Performance of Jatropha curcas L. in Semi-arid Zone: Seed Germination, Seedling Growth and Early Field Growth

There is a lack of information on basic agronomic properties of Jatropha curcas L. (jatropha) cultivation on the marginal lands in the semi-arids. Evaluation of agronomic performance of identified elite strains of J. curcas in marginal lands would be of paramount importance for addressing gap areas in their agronomic properties and subsequently for harnessing their optimum economic potentials. The present study undertook the task of analysing the growth performance of a high oil bearing elite strain of J. curcas–DARL-2 in degraded land in semi-arid zone of Deccan Plateau, India. While undertaking the assessment of growth performance of elite strain DARL-2, two other native (wild) strains (namely AHN-1 and AHN-2) of J. curcas were also considered so that a comparative evaluation could be carried out. The role of gypsum was also investigated on J. curcas in the nursery stage as well its carry over effects on growth performance of transplanted trees in the field. Two types of substrates, gypsum-treated soil (GS) and untreated soil (SL) were used for growing seedlings of all the three jatropha strains. Seedlings (120-days-old) of DARL-2 exhibited greater plant height, collar diameter and number of branches but root length was greater in the local strains. In the second year of field transplantation, DARL-2 strain exhibited significantly (p<0.05) greater plant height and number of branches/plant. No carry over effects of gypsum treatment were observed in field transplanted plants as none of the growth parameters significantly varied among the substrate types