We investigated the Effects of plantation development, seasons, and soil depth on soil microbial indices in Gmelina arborea plantations in south-western Nigeria. Soil samples were obtained from the soil depths of 0-15...We investigated the Effects of plantation development, seasons, and soil depth on soil microbial indices in Gmelina arborea plantations in south-western Nigeria. Soil samples were obtained from the soil depths of 0-15 and 15-30 cm from plantations of six different ages during the rainy season, dry seasons, and their transitions. We used plate count and fumigation-extraction methods to determine microbe population and microbial biomass carbon （MB-C） and nitrogen （MB-N）, respectively. Plantation age did not affect microbial indices, implying a non-significant effect of plantation development on microbial communities. It could also imply that soil microbial indices had already stabilized in the sampled plantations. Seasonal variation and soil depth had significant effects on microbial indices. At 0-15 cm soil depth, mean MB-C increased from 50.74 μg·g^-1 during the peak of the dry season （i.e. March） to 99.58μg·g-1 during the peak of the rainy season （i.e. September）, while it increased from 36.22μg·.g^-1 to 75.31μg·.g^-1 at 15-30 cm soil depth between the same seasonal periods. Bacteria populations and MB-N showed similar increasing trends. Correlations between MB-C, MB-N, microbe populations, and rainfall were positive and linear. Significantly higher microbial activities took place in the plantations during the rainy season, increased with soil wetness, and decreased at greater soil depth.展开更多
Arsenic （As） in the soils of South-Eastern Bangladesh is not rely a threat for the health of millions of people but also a problem for plant growth due to its higher concentration in soil. Gmelina arborea Linn. is a...Arsenic （As） in the soils of South-Eastern Bangladesh is not rely a threat for the health of millions of people but also a problem for plant growth due to its higher concentration in soil. Gmelina arborea Linn. is a promising fast growing tree species in Bangladesh which has dso a potential to be planted in arsenic contaminated areas. This study tssessed the role of arbuscular mycorrhizal （AM） fungi on the growth of 7. arborea in arsenic amended soils at nursery stage. Before sowing ;eeds, soils were treated with four different concentrations （10 mg.kg^-1, 25 mg.kg^-1, 50 mg.kg^-1, and 100 mg.kg^-1） of Arsenic. Growth parameters length of shoot and root, collar diameter, fresh and dry weight of shoot and root） of the plant, and mycorrhizal root colonization and spore population in the rhizosphere soil of G. arborea were recorded. Mycorrhizal seedlings showed better growth than non-mycorrhizal eedlings. Myeorrhizal seedlings planted in soil with 10-mg.kg^-1 arsenic howed best performance in terms of growth, biomass and mycorrhizal ：olonization, compared to other treatments with higher concentration of Lrsenie. With increasing arsenic concentration, growth of seedlings, nycorrhizal infection rate and spore population, all decreased ignificantly （p〈0.05）. The mycorrhizal seedlings had as much as 40% higher increment in total growth and 2.4 times higher increment in biomass compared to non-mycorrhizal seedlings. The study clearly indicated that mycorrhizal inoculation could reduce the harmful effects of arsenic on the initial growth of G. arborea Linn. in degraded soil at nursery stage.展开更多
Objective: To study the effects of aqueous extract of Gmelina arborea bark on normoglycemic levels and streptozotocin (STZ) induced diabetes in rats. Methods: After single administration of the aqueous extract, plasma...Objective: To study the effects of aqueous extract of Gmelina arborea bark on normoglycemic levels and streptozotocin (STZ) induced diabetes in rats. Methods: After single administration of the aqueous extract, plasma glucose level was determined up to 6 h. In subacute study, the aqueous extract was administered for 28 d and plasma glucose level was determined weekly. The diabetes was induced in rats by the intraperitoneal injection of STZ at a dose of 55 mg/kg body weight. The diabetic animals were divided into four groups containing six in each: Group 栺 diabetic control, Group 栻 and 栿 treated with the aqueous extract respectively at a dose of 250 and 500 mg/kg body weight once daily and Group 桇 treated with glibenclamide at a dose of 0.6 mg/kg body weight once daily. In acute study, the aqueous extract and glibenclamide were administered orally to rats. Plasma glucose levels were determined at 30, 60, 120, 240 and 360 min after the administration of the test samples. To study subacute effects, test samples (the aqueous extract and glibenclamide) were administered for 28 d consecutively. The effects of each test sample on plasma glucose level, body weight as well as food and water intake were also monitored weekly. The oral glucose tolerance test and biochemical indicators were estimated on day 28. Results: The aqueous extract did not significantly decrease the plasma glucose level in the normoglycemic rats as shown by the acute and subacute assays. However, after oral administration of the aqueous extract, the plasma glucose level was significantly ( P<0.001) decreased in the diabetic rats in the acute study. The long-term administration of the aqueous extract significantly ( P<0.001) reduced plasma glucose levels of the diabetic rats. Additionally, the aqueous extract also reduced loss of body weight and significantly decreased food and water intake in the diabetic animals. Nevertheless, no effects on biochemical indicators were observed at the selected doses. Conclusions: The aqueous extract of Gmelina arborea bark had antihyperglycemic activity against STZ induced diabetes in rats, after single and subacute oral administration. Moreover, it did not show significant glucose lowering effect in normoglycemic rats.展开更多
Objective:To study the effects of aqueous extract of Gmelina arborea bark on normoglycemic levels and streptozotocin(STZ) induced diabetes in rats.Methods:After single administration of the aqueous extract,plasma gluc...Objective:To study the effects of aqueous extract of Gmelina arborea bark on normoglycemic levels and streptozotocin(STZ) induced diabetes in rats.Methods:After single administration of the aqueous extract,plasma glucose level was determined up to 6 h.In subacute study,the aqueous extract was administered for 28 d and plasma glucose level was determined weekly.The diabetes was induced in rats by the intraperitoneal injection of STZ at a dose of 55 mg/kg body weight.The diabetic animals were divided into four groups containing six in each:CroupⅠdiabetic control,GroupⅡandⅢtreated with the aqueous extract respectively at a dose of 250 and 500 mg/kg body weight once daily and GroupⅣtreated with glibenelamide at a dose of 0.6 mg/kg body weight once daily.In acute study,the aqueous extract and glibenclamide were administered orally to rats.Plasma glucose levels were determined at 30,60,120,240 and 360 min after the administration of the test samples.To study subacute effects,test samples(the aqueous extract and glibenelamide) were administered for 28 d consecutively.The effects of each test sample on plasma glucose level,body weight as well as food and water intake were also monitored weekly. The oral glucose tolerance test and biochemical indicators were estimated on day 28.Results: The aqueous extract did not significantly decrease the plasma glucose level in the normoglycemic rats as shown by the acute and subacute assays.However,after oral administration of the aqueous extract,the plasma glucose level was significantly(P【0.001) decreased in the diabetic rats in the acute study.The long-term administration of the aqueous extract significantly(P【0.001) reduced plasma glucose levels of the diabetic rats.Additionally,the aqueous extract also reduced loss of body weight and significantly decreased food and water intake in the diabetic animals.Nevertheless,no effects on biochemical indicators were observed at the selected doses. Conclusions:The aqueous extract of Gmelina arborea bark had antihyperglycemic activity against STZ induced diabetes in rats,after single and subacute oral administration.Moreover,it did not show significant glucose lowering effect in normoglycemic rats.展开更多
The use of cyanidin as a metallochromic agent in analyses of heavy metal is reported. Cyanidin is a ligand that was extracted from Gmelina arborea fruit and characterized. The cyanidin was used to form complexes with ...The use of cyanidin as a metallochromic agent in analyses of heavy metal is reported. Cyanidin is a ligand that was extracted from Gmelina arborea fruit and characterized. The cyanidin was used to form complexes with metals in five fish samples for the quantitative determination of Cu, Zn, Ca and Mg. The optimum pH for absorbances of the cyanidin-metal complexes was observed at 5. Experimental results obtained using cyanidin were compared with analyses results obtained by Atomic absorption spectrophotometry (AAS) and both methods were evaluated using paired T-test to ascertain the suitability of cyanidin as metallochromic agent for the quantitative determination of heavy metals in fish samples. A null hypothesis that cyanidin method is a good alternative to AAS was accepted for the analyses of Cu and Zn (p > 0.05). The paired T-test, however rejected the null hypothesis for the determination of Ca and Mg (p < 0.05). This study has provided a cheap, sensitive, rapid, simple and easy method for metal determination in analytical samples.展开更多
文摘We investigated the Effects of plantation development, seasons, and soil depth on soil microbial indices in Gmelina arborea plantations in south-western Nigeria. Soil samples were obtained from the soil depths of 0-15 and 15-30 cm from plantations of six different ages during the rainy season, dry seasons, and their transitions. We used plate count and fumigation-extraction methods to determine microbe population and microbial biomass carbon （MB-C） and nitrogen （MB-N）, respectively. Plantation age did not affect microbial indices, implying a non-significant effect of plantation development on microbial communities. It could also imply that soil microbial indices had already stabilized in the sampled plantations. Seasonal variation and soil depth had significant effects on microbial indices. At 0-15 cm soil depth, mean MB-C increased from 50.74 μg·g^-1 during the peak of the dry season （i.e. March） to 99.58μg·g-1 during the peak of the rainy season （i.e. September）, while it increased from 36.22μg·.g^-1 to 75.31μg·.g^-1 at 15-30 cm soil depth between the same seasonal periods. Bacteria populations and MB-N showed similar increasing trends. Correlations between MB-C, MB-N, microbe populations, and rainfall were positive and linear. Significantly higher microbial activities took place in the plantations during the rainy season, increased with soil wetness, and decreased at greater soil depth.
文摘Arsenic （As） in the soils of South-Eastern Bangladesh is not rely a threat for the health of millions of people but also a problem for plant growth due to its higher concentration in soil. Gmelina arborea Linn. is a promising fast growing tree species in Bangladesh which has dso a potential to be planted in arsenic contaminated areas. This study tssessed the role of arbuscular mycorrhizal （AM） fungi on the growth of 7. arborea in arsenic amended soils at nursery stage. Before sowing ;eeds, soils were treated with four different concentrations （10 mg.kg^-1, 25 mg.kg^-1, 50 mg.kg^-1, and 100 mg.kg^-1） of Arsenic. Growth parameters length of shoot and root, collar diameter, fresh and dry weight of shoot and root） of the plant, and mycorrhizal root colonization and spore population in the rhizosphere soil of G. arborea were recorded. Mycorrhizal seedlings showed better growth than non-mycorrhizal eedlings. Myeorrhizal seedlings planted in soil with 10-mg.kg^-1 arsenic howed best performance in terms of growth, biomass and mycorrhizal ：olonization, compared to other treatments with higher concentration of Lrsenie. With increasing arsenic concentration, growth of seedlings, nycorrhizal infection rate and spore population, all decreased ignificantly （p〈0.05）. The mycorrhizal seedlings had as much as 40% higher increment in total growth and 2.4 times higher increment in biomass compared to non-mycorrhizal seedlings. The study clearly indicated that mycorrhizal inoculation could reduce the harmful effects of arsenic on the initial growth of G. arborea Linn. in degraded soil at nursery stage.
文摘Objective: To study the effects of aqueous extract of Gmelina arborea bark on normoglycemic levels and streptozotocin (STZ) induced diabetes in rats. Methods: After single administration of the aqueous extract, plasma glucose level was determined up to 6 h. In subacute study, the aqueous extract was administered for 28 d and plasma glucose level was determined weekly. The diabetes was induced in rats by the intraperitoneal injection of STZ at a dose of 55 mg/kg body weight. The diabetic animals were divided into four groups containing six in each: Group 栺 diabetic control, Group 栻 and 栿 treated with the aqueous extract respectively at a dose of 250 and 500 mg/kg body weight once daily and Group 桇 treated with glibenclamide at a dose of 0.6 mg/kg body weight once daily. In acute study, the aqueous extract and glibenclamide were administered orally to rats. Plasma glucose levels were determined at 30, 60, 120, 240 and 360 min after the administration of the test samples. To study subacute effects, test samples (the aqueous extract and glibenclamide) were administered for 28 d consecutively. The effects of each test sample on plasma glucose level, body weight as well as food and water intake were also monitored weekly. The oral glucose tolerance test and biochemical indicators were estimated on day 28. Results: The aqueous extract did not significantly decrease the plasma glucose level in the normoglycemic rats as shown by the acute and subacute assays. However, after oral administration of the aqueous extract, the plasma glucose level was significantly ( P<0.001) decreased in the diabetic rats in the acute study. The long-term administration of the aqueous extract significantly ( P<0.001) reduced plasma glucose levels of the diabetic rats. Additionally, the aqueous extract also reduced loss of body weight and significantly decreased food and water intake in the diabetic animals. Nevertheless, no effects on biochemical indicators were observed at the selected doses. Conclusions: The aqueous extract of Gmelina arborea bark had antihyperglycemic activity against STZ induced diabetes in rats, after single and subacute oral administration. Moreover, it did not show significant glucose lowering effect in normoglycemic rats.
文摘Objective:To study the effects of aqueous extract of Gmelina arborea bark on normoglycemic levels and streptozotocin(STZ) induced diabetes in rats.Methods:After single administration of the aqueous extract,plasma glucose level was determined up to 6 h.In subacute study,the aqueous extract was administered for 28 d and plasma glucose level was determined weekly.The diabetes was induced in rats by the intraperitoneal injection of STZ at a dose of 55 mg/kg body weight.The diabetic animals were divided into four groups containing six in each:CroupⅠdiabetic control,GroupⅡandⅢtreated with the aqueous extract respectively at a dose of 250 and 500 mg/kg body weight once daily and GroupⅣtreated with glibenelamide at a dose of 0.6 mg/kg body weight once daily.In acute study,the aqueous extract and glibenclamide were administered orally to rats.Plasma glucose levels were determined at 30,60,120,240 and 360 min after the administration of the test samples.To study subacute effects,test samples(the aqueous extract and glibenelamide) were administered for 28 d consecutively.The effects of each test sample on plasma glucose level,body weight as well as food and water intake were also monitored weekly. The oral glucose tolerance test and biochemical indicators were estimated on day 28.Results: The aqueous extract did not significantly decrease the plasma glucose level in the normoglycemic rats as shown by the acute and subacute assays.However,after oral administration of the aqueous extract,the plasma glucose level was significantly(P【0.001) decreased in the diabetic rats in the acute study.The long-term administration of the aqueous extract significantly(P【0.001) reduced plasma glucose levels of the diabetic rats.Additionally,the aqueous extract also reduced loss of body weight and significantly decreased food and water intake in the diabetic animals.Nevertheless,no effects on biochemical indicators were observed at the selected doses. Conclusions:The aqueous extract of Gmelina arborea bark had antihyperglycemic activity against STZ induced diabetes in rats,after single and subacute oral administration.Moreover,it did not show significant glucose lowering effect in normoglycemic rats.
文摘The use of cyanidin as a metallochromic agent in analyses of heavy metal is reported. Cyanidin is a ligand that was extracted from Gmelina arborea fruit and characterized. The cyanidin was used to form complexes with metals in five fish samples for the quantitative determination of Cu, Zn, Ca and Mg. The optimum pH for absorbances of the cyanidin-metal complexes was observed at 5. Experimental results obtained using cyanidin were compared with analyses results obtained by Atomic absorption spectrophotometry (AAS) and both methods were evaluated using paired T-test to ascertain the suitability of cyanidin as metallochromic agent for the quantitative determination of heavy metals in fish samples. A null hypothesis that cyanidin method is a good alternative to AAS was accepted for the analyses of Cu and Zn (p > 0.05). The paired T-test, however rejected the null hypothesis for the determination of Ca and Mg (p < 0.05). This study has provided a cheap, sensitive, rapid, simple and easy method for metal determination in analytical samples.
