RESUMO
Aim: Partial purification and characterization of amyloglucosidase from an insect were carried out to determine the physicochemical properties of the enzyme. Study Design: It was designed to dissect digestive tracts from the American cockroach, Periplaneta americana, and to investigate the properties of the gut amyloglucosidase with a view to predicting possible industrial and pest control applications. Place and Duration of Study: The study was carried out in the Insect Physiology Laboratory of the Department of Crop Production and Protection and Department of Biochemistry, Obafemi Awolowo University, Ile-Ife, Nigeria between June and October, 2013. Methodology: Newly emerged cockroaches were dissected in ice-cold phosphate buffer and digestive tracts were collected to prepare the crude enzyme extract. Standard bioassays were constituted to purify and characterize amyloglucosidase. Results: The purification had a 71.6% yield and a specific activity of 2.53 U/mg protein. On soluble starch, the enzyme exhibited optimum activity at pH 4.0 with a Michaelis constant (Km) of 1.67 mg/ml and a maximum velocity (Vmax) of 10mg/ml/min. Amyloglucosidase activity was enhanced by Mn2+ but it was slightly inhibited by Sn2+, Mg2+ and Ni2+, while Zn2+ caused a 50% inhibition. Optimum temperature for the partially purified enzyme was 40°C and it lost about 90% of its original activity when incubated beyond 20 min at 60°C. Conclusion: Obtained results suggested that starch degradation using amyloglucosidase from P. americana could be done around pH 4 and at temperature around 40°C. This work appears to give the first report on physicochemical properties of amyloglucosidase in insects. Further studies would be needed to determine the possibility of using molecular techniques in inducing amyloglucosidase- Zn2+ complex in P. americana and to find a probable source of thermophilic amyloglucosidase which would be of importance in an industrial context.
RESUMO
The objective of the study was to comparatively verify the effects of aqueous extracts of three plants on some biochemical parameters following ethanol administration with a view to ascertaining the role of the extracts in ameliorating ethanol toxicity. A total of forty rats were divided into eight groups (n=5). Group A were control rats; Group B were administered with absolute ethanol; Group C were ethanol administered rats treated with Xylopia aethiopica; Groups D were ethanol administered rats treated with Fiscus mucuso, Group E were ethanol administered rats treated with Anthocleista vogelli; Group F were normal rats administered orally with Xylopia aethiopica; Group G were normal rats administered orally with Fiscus mucuso; Group H were normal rats administered orally with Anthocleista vogelli. At the end of the experimental period, the animals were sacrificed and serum was obtained for total protein, uric acid, creatinin, urea, aspartate aminotrasferase (AST) and alanine aminotransferase (ALT) analysis using respective research kits. The result showed that Xylopia aethiopica had protective effect on the kidney as compared with Fiscus mucuso and Anthocleista vogelli treated rats. Also, The AST and ALT was lowered with the beginning of Xylopia aethiopia treatment. The total protein, creatinin and urea were slightly (p>0.05) affected with ethanol, an effect which was normalized with the beginning of extract treatment. It can be concluded that Xylopia aethiopica had a better reno-protective and hepatoprotective effect than Anthocleista vogelli and Fiscus mucuso extract as evident in its ameliorative role on the biochemical profiles.