Enhanced Enzymatic Transformation of 1-Naphthol in the Presence of Catechol by Peroxidase

Islam, A.K.M. Mydul,Lee, Sung-Eun,Kim, Jang-Eok The Korean Society for Applied Biological Chemistr 2014 Applied Biological Chemistry (Appl Biol Chem) Vol.57 No.2

Effect of catechol on 1-naphthol transformation by horse radish peroxidase (HRP) was examined. The impact of catechol to 1-naphthol ratio, enzyme activity, pH, and reaction time in solution were studied. The results obtained indicated that, in the presence of catechol, 1-naphthol transformation by peroxidase shows enhancement greater than that in an equivalent catechol free system. Only 27% of 1-naphthol (0.3 mM) was able to transform when catechol was absent in solution, but reached 79% in its presence (3.0 mM) in 0.1M sodium phosphate buffer (pH 7.0), and 0.3 mM $H_2O_2$ by peroxidase (0.5 unit/mL) after 3 h. The 1-naphthol transformation rate was accelerated by increase of pH or HRP concentration. High-performance liquid chromatography analysis was performed to characterize transformation products based on their relative polarities, and molecular weights of products were identified by mass spectrometry. The transformation products were found to be (hydroxy) naphthoquinones, 1-naphthol: hydroxy-naphthoquinone, and 1-naphthol oligomers (dimer, trimer, tetramer) with the molecular weights (m/z) ranging 100-600. Liquid chromatography-tandem mass spectrometry technique, to the best of our knowledge, was used for the first time to elucidate the product structure at m/z 191. The study shows that 1-naphthol is transformed rapidly by peroxidase when catechol is present, which could be useful information for improving the efficiencies of decontamination techniques.

Performance Evaluation of Finite Queue Switching Under Two-Dimensional M/G/1(m) Traffic

Islam, Md. Syeful,Rahman, Md. Rezaur,Roy, Anupam,Islam, Md. Imdadul,Amin, M.R. Korea Information Processing Society 2011 Journal of information processing systems Vol.7 No.4

In this paper we consider a local area network (LAN) of dual mode service where one is a token bus and the other is a carrier sense multiple access with a collision detection (CSMA/CD) bus. The objective of the paper is to find the overall cell/packet dropping probability of a dual mode LAN for finite length queue M/G/1(m) traffic. Here, the offered traffic of the LAN is taken to be the equivalent carried traffic of a one-millisecond delay. The concept of a tabular solution for two-dimensional Poisson's traffic of circuit switching is adapted here to find the cell dropping probability of the dual mode packet service. Although the work is done for the traffic of similar bandwidth, it can be extended for the case of a dissimilar bandwidth of a circuit switched network.

Molecular identification and virulence of six isolates of Metarhizium anisopliae (Deuteromycotina: Hyphomycetes) to Bemisia tabaci Q biotype

M.T. Islam,D. Omar,M. Shabanimofrad 한국응용곤충학회 2014 Journal of Asia-Pacific Entomology Vol.17 No.3

The aimof this studywas to investigate the molecular identification and virulence of the entomopathogenic fungusMetarhizium anisopliae. Initially, the alignments of nucleotide sequences of the internal transcribed spacer(ITS) 1-5.8S-ITS4 regions of six isolates–TFFH1, TFFH3, PR1, MAP, GT3, and GT2–were investigated using GenBankITS sequences for the same region and species of fungus. Thereafter, the in vitro (germination, vegetative growth,and sporulation) and the in vivo (%mortality of Bemisia tabaci) virulence of the funguswere investigated. A BLASTsearch of the ITS1 region revealed a match to a sequence registered under the accession number forM. anisopliae. The submitted sequence datawere registered and providedwith the accession numbers JX041507 to JX0415012,which were released in August 2012 (GenBank). In the virulence experiments, the highest germination percentage,vegetative growth, and sporulation of M. anisopliae were observed in the isolate PR1, with mean values of97.2%, 4.6 cm, and 7.2 × 106 conidia/ml, respectively; while the highest mortality percentage of B. tabaci was observedin the isolate GT3,with an mean value of 84.3%. This study concludes that all the six tested isolates–TFFH1,TFFH3, PR1, MAP, GT3, and GT2–are M. anisopliae and the isolates PR1 and GT3 are more virulent to B. tabaci thanthat by the other four isolates.

Performance Evaluation of Finite Queue Switching Under Two-Dimensional M/G/1(m) Traffic

Md. Syeful Islam,Md Rezaur Rahman,Anupam Roy,Md Imdadul Islam,M. R. Amin 한국정보처리학회 2011 Journal of information processing systems Vol.7 No.4

Iturin produced by Bacillus pumilus HY1 from Korean soybean sauce (kanjang) inhibits growth of aflatoxin producing fungi

Cho, K.M.,Math, R.K.,Hong, S.Y.,Asraful Islam, S.Md.,Mandanna, D.K.,Cho, J.J.,Yun, M.G.,Kim, J.M.,Yun, H.D. Butterworths ; Taylor Francis ; Elsevier Science 2009 FOOD CONTROL Vol.20 No.4

A new strain of Bacillus pumilus, designated HY1, was isolated from Korean soybean sauce (kanjang). This classification was based on morphological, physiological, and chemotaxonomic features of the organism that identified it as a Gram-positive bacillus, and confirmed by 16S rDNA based phylogenetic analysis. Strain HY1 showed strong antifungal activity against the aflatoxin-producing fungi Aspergillus flavus and Aspergillus parasiticus, two common contaminants of fermented soybean foods. MALDI-TOF mass analysis revealed that the antifungal compound was similar to the known lipopeptide iturin. Iturin purified from strain HY1 had three isoforms with protonated masses of m/z 1,043.4, 1,057.4, and 1,071.4, and different structures in combination with Na<SUP>+</SUP> ion using MALDI-TOF MS. Purified iturin from HY1 also exhibited antifungal activity against A. flavus and A. parasiticus.

Enhanced Enzymatic Transformation of 1-Naphthol in the Presence of Catechol by Peroxidase

A. K. M. Mydul Islam,이성은,김장억 한국응용생명화학회 2014 Applied Biological Chemistry (Appl Biol Chem) Vol.57 No.2

Effect of catechol on 1-naphthol transformation byhorse radish peroxidase (HRP) was examined. The impact ofcatechol to 1-naphthol ratio, enzyme activity, pH, and reactiontime in solution were studied. The results obtained indicated that,in the presence of catechol, 1-naphthol transformation byperoxidase shows enhancement greater than that in an equivalentcatechol free system. Only 27% of 1-naphthol (0.3 mM) was ableto transform when catechol was absent in solution, but reached79% in its presence (3.0 mM) in 0.1M sodium phosphate buffer(pH 7.0), and 0.3 mM H2O2 by peroxidase (0.5 unit/mL) after 3 h. The 1-naphthol transformation rate was accelerated by increase ofpH or HRP concentration. High-performance liquid chromatographyanalysis was performed to characterize transformation productsbased on their relative polarities, and molecular weights of productswere identified by mass spectrometry. The transformation productswere found to be (hydroxy) naphthoquinones, 1-naphthol:hydroxy-naphthoquinone, and 1-naphthol oligomers (dimer, trimer,tetramer) with the molecular weights (m/z) ranging 100–600. Liquid chromatography-tandem mass spectrometry technique, tothe best of our knowledge, was used for the first time to elucidatethe product structure at m/z 191. The study shows that 1-naphtholis transformed rapidly by peroxidase when catechol is present,which could be useful information for improving the efficienciesof decontamination techniques.

Performance Evaluation of the VoIP Services of the Cognitive Radio System, Based on DTMC

Habiba, Ummy,Islam, Md. Imdadul,Amin, M.R. Korea Information Processing Society 2014 Journal of information processing systems Vol.10 No.1

In recent literature on traffic scheduling, the combination of the two-dimensional discrete-time Markov chain (DTMC) and the Markov modulated Poisson process (MMPP) is used to analyze the capacity of VoIP traffic in the cognitive radio system. The performance of the cognitive radio system solely depends on the accuracy of spectrum sensing techniques, the minimization of false alarms, and the scheduling of traffic channels. In this paper, we only emphasize the scheduling of traffic channels (i.e., traffic handling techniques for the primary user [PU] and the secondary user [SU]). We consider the following three different traffic models: the cross-layer analytical model, M/G/1(m) traffic, and the IEEE 802.16e/m scheduling approach to evaluate the performance of the VoIP services of the cognitive radio system from the context of blocking probability and throughput.

DEVELOPMENT OF STRAW BASED RATION FOR FEEDING RUMINANTS

Kibria, S.S.,Islam, M.R.,Saha, C.K. Asian Australasian Association of Animal Productio 1991 Animal Bioscience Vol.4 No.3

A CRD experiment with thirty growing cross bred calves were assigned at random to three treatments rations. 1) $T_0$, 0% Urea + 20% M. O. cake, 2) $T_1$, 1% Urea + 10% M. O. cake and 3) $T_2$, 2% Urea + 0% M. O. cake to develop a rice straw based ration for ruminants. Sweetish odour and yellowish colour were observed in good recovered silage. Organic matter varied from 87.45% to 89.63% whereas crude protein varied from 14.0% to 14.5% in each treatment. No significant differences were found among the nutrient composition of the ration. The dry matter in take (DMI) and dry matter digestibility was higher in $T_0$ (0% Urea) than those of ration containing 1% ($T_1$) and 2% Urea ($T_2$). The organic matter digestibility decreases with increasing doses of urea. The crude protein & nitrogen-free-extract digestibility were found higher in the ration $T_1$ containing 1% urea whereas crude fibre digestibility and available metabolizable energy (ME) were higher in $T_0$ containing no urea as compared to $T_1$ and $T_2$. Total digestible nutrient (TDN) decreases with the increase of urea level. The highest feed efficiency was found in $T_0$ having no urea and lowest was in $T_2$. The animals gained in weights from each ration. Highest gain in weight was found in $T_0$ ration, then followed $T_1$, and $T_2$. This is due to natural protein available in M. O. cake only. It is concluded that supplemetation of urea or M. O. cake with readily available energy source as molasses upto 20% of total dietary dry matter in a complete ration may increase the intake of low quality fibrous roughage only when nitrogen and mineral are not limiting factor.

Performance Evaluation of the VoIP Services of the Cognitive Radio System, Based on DTMC

( Ummy Habiba ),( Imdadul Islam ),( M R Amin ) 한국정보처리학회 2014 Journal of information processing systems Vol.10 No.1

In recent literature on traffic scheduling, the combination of the two dimensional discrete-time Markov chain (DTMC) and the Markov modulated Poisson process (MMPP) is used to analyze the capacity of VoIP traffic in the cognitive radio system. The performance of the cognitive radio system solely depends on the accuracy of spectrum sensing techniques, the minimization of false alarms, and the scheduling of traffic channels. In this paper, we only emphasize the scheduling of traffic channels (i.e., traffic handling techniques for the primary user [PU] and the secondary user [SU]). We consider the following three different traffic models: the cross-layer analytical model, M/G/1(m) traffic, and the IEEE 802.16e/m scheduling approach to evaluate the performance of the VoIP services of the cognitive radio system from the context of blocking probability and throughput.

Wheat Blast in Bangladesh: The Current Situation and Future Impacts

M,Tofazzal Islam,Kwang-Hyung Kim,Jaehyuk Choi 한국식물병리학회 2019 Plant Pathology Journal Vol.35 No.1

Wheat blast occurred in Bangladesh for the first time in Asia in 2016. It is caused by a fungal pathogen, Magnaporthe oryzae Triticum (MoT) pathotype. In this review, we focused on the current status of the wheat blast in regard to host, pathogen, and environment. Despite the many efforts to control the disease, it expanded to neighboring regions including India, the world s second largest wheat producer. However, the disease occurrence has definitely decreased in quantity, because of many farmers chose to grow alternate crops according to the government’s directions. Bangladesh government planned to introduce blast resistant cultivars but knowledges about genetics of resistance is limited. The genome analyses of the pathogen population revealed that the isolates caused wheat blast in Bangladesh are genetically close to a South American lineage of Magnaporthe oryzae. Understanding the genomes of virulent strains would be important to find target resistance genes for wheat breeding. Although the drier winter weather in Bangladesh was not favorable for development of wheat blast before, recent global warming and climate change are posing an increasing risk of disease development. Bangladesh outbreak in 2016 was likely to be facilitated by an extraordinary warm and humid weather in the affected districts before the harvest season. Coordinated international collaboration and steady financial supports are needed to mitigate the fearsome wheat blast in South Asia before it becomes a catastrophe.