Search Results

You are looking at 1 - 4 of 4 items for

  • Author: Md. Shahidul Islam x
Clear All Modify Search
Open access

Md Masud Sarker and Md. Shahidul Islam

Abstract

Social capital supports toward participating in political activities in democratic countries. This study tries to examine the relation between social capital and political participation in Bangladesh. A cross-sectional study was conducted in Sylhet Sadar Upazila (sub-district) of north-eastern Bangladesh. A total of 100 respondents - who are above 23 years of age - were selected by using systematic random sampling technique for a face-to-face interview. Chi-square test and Fisher Exact test were applied to measure the association between social capital dimensions and political participation. The results show that social networks, civic participation, norms of reciprocity and social trusts are significantly associated with political participation in Bangladesh. This result suggests that social capital may have an effect towards an increment of a political participation in Bangladesh.

Open access

Afroza Ahammed Shimu and Md. Shahidul Islam

Abstract

The ready-made garments (RMG) sector of Bangladesh is considered as a key driver for the Bangladeshi Economy. This paper tries to examine the impacts of macroeconomic variables on the RMG export growth of this country. For this purpose, secondary data was collected from various sources. Multiple linear regression model was applied to measure the effects of macroeconomic variables on the RMG export growth. Trade Entropy and the Competitiveness Index were applied to understand the status of RMG sector in the world market. After that, to check the accuracy of the regression model, three types of econometric problems were tested in this study. Firstly, heteroscedasticity problem was tested by graphical presentation. Secondly, auto-correlation problem was tested by Durbin Watson test. Thirdly, multicollinearity problem was tested by correlation matrix and Variance Influence Factor (VIF). The empirical results show that for every unit increase of the growth rate of official exchange rate, inflation rate, real interest rate, and female unemployment rate; the growth rate of RMG export decreases by 1.159, 0.055, 0.034, and 0.068 units, respectively.

Open access

Mohammed Auwal Ibrahim, Neil Anthony Koorbanally and Md. Shahidul Islam

Abstract

This study evaluated the in vitro antioxidative activity of Khaya senegalensis extracts and inhibitory effects of some solvent fractions on α-glucosidase and α-amylase activities. The stem bark, root and leaf samples of the plant were sequentially extracted with ethyl acetate, ethanol and water and then tested for antioxidative activity. Our findings revealed that the ethanolic extract of the root had the highest antioxidative activity. Solvent-solvent fractionation of the root ethanolic extract yielded a butanol fraction that showed higher antioxidative activity than other fractions. Furthermore, the butanol fraction had significantly higher (p < 0.05) α-glucosidase and α-amylase inhibitory activities with IC50 values of 2.89 ± 0.46 and 97.51 ± 5.72 μg mL-1, respectively. Enzyme kinetic studies indicated that the butanol fraction is a non-competitive inhibitor for α-glucosidase with an inhibition binding constant Ki of 1.30 μg mL-1 and a competitive inhibitor of α-amylase with a Ki of 7.50 μg mL-1. GC-MS analysis revealed that the butanol fraction contained two chromones, p-anilinophenol and 3-ethyl-5-(3- ethyl-(3H)-benzothiazol-2-ylidene)-2-(p-tolylvinylamino)- 4-thiazolidinone. Data obtained in the study suggest that the butanol fraction derived from the ethanolic extract of K. senegalensis root possessed excellent antioxidative as well as α-glucosidase and a-amylase inhibitory activities while chromones and/or p-anilinophenol could be the main bioactive compounds responsible for the observed activities.

Open access

Olajumoke A. Oyebode, Ochuko L. Erukainure, Neil A. Koorbanally and Md. Shahidul Islam

Abstract

In this study, we identified bioactive compounds from the ethanolic extracts of the leaves, stem bark and root bark of Acalypha wilkesiana through GC-MS analysis and investigated the effects of these extracts on some of the enzymes linked to type 2 diabetes. Plant parts were extracted sequentially with ethyl acetate, ethanol and water. GC-MS analysis revealed the presence of long-chain alkyl acids, esters, ketones and alcohols including phytol and phytol acetate along with some secondary metabolites such as xanthone, vitamin E and various types of sterols including stigmasterol, campesterol and sitosterol. Ethanolic extracts of all the parts showed a dose- -dependent inhibition of α-glucosidase and α-amylase activity. The extracts also demonstrated anti-lipase activity. The ethanolic extract of root bark showed the highest inhibition of enzymes compared to other extracts. The EC50 values (concentrations for 50 % inhibition) of α-glucosidase, α-amylase and lipase inhibition were 35.75 ± 1.95, 6.25 ± 1.05 and 101.33 ± 5.21 μg mL-1, resp. The study suggests that A. wilkesiana ethanolic extracts have the ability to inhibit the activity of enzymes linked to type 2 diabetes. Further studies are needed to confirm the responsible bioactive compounds in this regard.