Jessore University of Science & Technology

About: Jessore University of Science & Technology is a based out in . It is known for research contribution in the topics: Adsorption & Population. The organization has 811 authors who have published 974 publications receiving 10471 citations.

Efficacy of soil-borne Enterobacter sp. for carbofuran degradation: HPLC quantitation of degradation rate

Abstract: Excessive use of pesticides in agricultural fields is a matter of great concern for living beings as well as the environment across the world, in particular, the third world countries. Therefore, there is an urgent need to find out an effective way to degrade these hazardous chemicals from the soil in an environment-friendly way. In the current project, a bacterial species were isolated through enrichment culture from carbofuran-supplemented rice-field soil and identified as a carbofuran degrader. The rate of carbofuran degradation by this bacterial species was evaluated using reverse-phase high-performance liquid chromatography (RP-HPLC), which confirmed the ability to utilize as a carbon source up to 4 µg/ml of 99% technical grade carbofuran. The morphological, physiological, biochemical characteristics and phylogenetic analysis of the 16S rRNA sequence showed that this strain belongs to the genus of Enterobacter sp. (sequence accession number LC368285 in DDBJ), and the optimum growth condition for the isolated strain was 37°C at pH 7.0. Moreover, an antibiotic sensitivity test showed that it was susceptible to azithromycin, penicillin, ceftazidime, ciprofloxacin, and gentamycin, and the minimal inhibitory concentration value of gentamycin was 400 μg/ml against the bacteria. It shows beyond doubt from the RP-HPLC quantification that the isolated bacterium has the ability to detoxify carbofuran (99% pure). Finally, the obtained results imply that the isolated strain of Enterobacter can be used as a potential and effective carbofuran degrader for bioremediation of contaminated sites through bioaugmentation.

Nutritional Value and Biofunctionalities of Two Edible Green Seaweeds (Ulva lactuca and Caulerpa racemosa) from Indonesia by Subcritical Water Hydrolysis

Abstract: Caulerpa racemosa (sea grapes) and Ulva lactuca (sea lettuces) are edible green seaweeds and good sources of bioactive compounds for future foods, nutraceuticals and cosmeceutical industries. In the present study, we determined nutritional values and investigated the recovery of bioactive compounds from C. racemosa and U. lactuca using hot water extraction (HWE) and subcritical water extraction (SWE) at different extraction temperatures (110 to 230 °C). Besides significantly higher extraction yield, SWE processes also give higher protein, sugar, total phenolic (TPC), saponin (TSC), flavonoid contents (TFC) and antioxidant activities as compared to the conventional HWE process. When SWE process was applied, the highest TPC, TSC and TFC values were obtained from U. lactuca hydrolyzed at reaction temperature 230 °C with the value of 39.82 ± 0.32 GAE mg/g, 13.22 ± 0.33 DE mg/g and 6.5 ± 0.47 QE mg/g, respectively. In addition, it also showed the highest antioxidant activity with values of 5.45 ± 0.11 ascorbic acid equivalents (AAE) mg/g and 8.03 ± 0.06 trolox equivalents (TE) mg/g for ABTS and total antioxidant, respectively. The highest phenolic acids in U. lactuca were gallic acid and vanillic acid. Cytotoxic assays demonstrated that C. racemosa and U. lactuca hydrolysates obtained by HWE and SWE did not show any toxic effect on RAW 264.7 cells at tested concentrations after 24 h and 48 h of treatment (p < 0.05), suggesting that both hydrolysates were safe and non-toxic for application in foods, cosmeceuticals and nutraceuticals products. In addition, the results of this study demonstrated the potential of SWE for the production of high-quality seaweed hydrolysates. Collectively, this study shows the potential of under-exploited tropical green seaweed resources as potential antioxidants in nutraceutical and cosmeceutical products.

Modeling the potential impacts of global climate change in Bangladesh: An optimal control approach

Abstract: One of the most hot issues in the recent environmental research worldwide has become the harmful effects of climate change on the ecosystems and environment due to global warming. Bangladesh is one of the most vulnerable countries not only in the South East Asia but also in the world. It is predicted that a large portion of the South-western region of Bangladesh will go under sea in the next 50 to 100 years due to sea level rise. In this paper, we first discuss some potential impacts of climate change in Bangladesh and its aftermath on the ecosystems and secondly, we study a mathematical model of climate change in terms of ordinary differential equations (ODEs) and apply optimal control techniques in the form of Pontryagin Maximum Principle (PMP) to investigate the control strategy of greenhouse gases (GHGs). We study the model numerically using some known nonlinear ‘optimal control solvers’ and the results are illustrated with numerical simulations.

Abundant new exact solutions to the fractional nonlinear evolution equation via Riemann-Liouville derivative

Abstract: The space–time fractional equal width (EW) and the space–time fractional generalized equal width (GEW) equations are two important models that represent nonlinear dispersive waves, namely, waves ensuing in the shallow water channel, 1-D wave generation ascending in the nonlinear dispersive medium estimation, cold plasma hydro-magnetic waves, chemical kinematics, electromagnetic interaction, etc. In this article, we search advanced and broad-spectrum wave solutions of the formerly indicated models in diverse families in conjunction with the Riemann-Liouville fractional derivative via the double ( G ′ / G , 1 / G )-expansion approach. The nonlinear fractional differential equations (NLFDEs) are transformed into ODEs by the composite function derivative and the chain rule putting together with the wave transformation. We acquire kink wave solution, multiple periodic solutions, single soliton solution, periodic wave solution and other types of soliton solutions by setting particular values of the embodied parameters. The suggested technique is functional, convenient, powerful, and computationally feasible to examine scores of NLFDEs.