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31.
Alam Khan Md Hedayetul Islam Md Ekramul Islam Md Abdul Alim Al-Bari Mst Shahnaj Parvin Mohammed Abu Sayeed Md Nurul Islam Md Ekramul Haque 《Biological research》2014,47(1)
Background
Tribolium castaneum (Herbst) is a harmful pest of stored grain and flour-based products in tropical and subtropical region. In the present study, rhizome of Drynaria quercifolia (J. Smith) was evaluated for pesticidal and pest repellency activities against T. castaneum, using surface film method and filter paper disc method, respectively. In addition, activity of the isolated compound 3,4-dihydroxybenzoic acid was evaluated against the pest.Results
Chloroform soluble fraction of ethanol extract of rhizome of D. quercifolia showed significant pesticidal activity at doses 0.88 to 1.77 mg/cm2 and significant pest repellency activity at doses 0.94 to 0.23 mg/cm2. No pesticidal and pest repellency activity was found for petroleum ether, ethyl acetate and methanol soluble fractions of ethanol extract as well as for 3,4-dihydroxybenzoic acid.Conclusion
Considering our findings it can be concluded that chloroform soluble fraction of rhizome of D. quercifolia is useful in controlling T. castaneum of stored grain and flour-based products.Electronic supplementary material
The online version of this article (doi:10.1186/0717-6287-47-51) contains supplementary material, which is available to authorized users. 相似文献32.
Md. Shamsul Arefin Md. Ariful Islam Md. Mokhlesur Rahman Md. Abdul Alim Sabry Hassan Mahmoud F. K. Soliman Mohamed M. Hassan Rajan Bhatt Akbar Hossain 《Phyton》2022,91(2):439-469
Sugarcane is one of the major important sugar yielding crops in Bangladesh. As an exhaustive crop, sugarcane removes a huge amount of plant nutrients from the soil. However, the combined use of organic and inorganic fertilizers can be a good approach to deal with nutrient depletion and promote sustainable crop production as well as improve soil health. Therefore, an attempt was made to identify the most fruitful and profitable integrated nutrient management on the aspects of growth, yield and quality of sugarcane in two consecutive growing seasons. Seven treatments: T1 = Control, T2 = 165:55:120:30:10:2.5:4 kg N:P:K:S:Mg:Zn:B ha−1, T3 = Poultry Litter (PL) at 5 t ha−1 + 95:51:87:9:10:2.5:4 kg N:P:K:S:Mg:Zn:B ha−1, T4 = Cow Dung (CD) at 15 t ha−1 + 36:52:60:17:10:2.5:4 kg N:P:K:S:Mg:Zn:B ha−1, T5 = Press Mud (PM) at 15 t ha−1 + 10:50:43:0:10:2.5:4 kg N:P:K:S:Mg:Zn:B ha−1, T6 = Mustard Oil Cake (MOC) at 0.5 t ha−1 + 140:54:115:25:10:2.5:4 kg N:P:K:S:Mg:Zn:B ha−1 and T7 = GM (Green Manure) at 5 t ha−1 + 140:53:100:28:10:2.5:4 kg N:P:K:S:Mg:Zn:B ha−1 were used in this experiment. Two years data showed that treatment T3 produced the maximum amount of tillers, total dry matter yield, millable sugarcane, cane yield and sugar yield, followed by the T4 treatment. The highest stalk heights were recorded in the T3 treatment, which was statistically similar to all other treatments except T1 and T2. The juice quality parameters viz., brix and pol in cane were found significant in treatment T3 while the highest purity was obtained in the T7 treatment. All the data of Jaggery (goor) quality parameters, the highest sucrose content, color transmittance, Jaggery (goor) recovery and the lowest ash content of Jaggery (goor) were observed in the T3 treatment, which was statistically similar to the T4 treatment in both seasons. The highest cost of production was obtained from the T6 treatment while the highest gross return, net return and BCR were recorded in the T3 treatment. No significant changes were found in one cycle of sugarcane in initial and post-harvest soil characteristics viz., pH, organic carbon, total N, and available P, K and S contents due to integrated use of different fertilizer packages. From the experimental findings, it was concluded that treatment T3 followed by T4 treatment would be the better productive and profitable integrated nutrient management technology for ensuring higher yields and quality of sugarcane without soil fertility degradation in the High Ganges River Floodplain soils. 相似文献
33.
Alim Isnansetyo Indah Istiqomah Muhtadi Shofihar Sinansari Rudi Kurnia Hernawan Triyanto Jaka Widada 《World journal of microbiology & biotechnology》2009,25(6):1103-1113
We isolated a marine bacterium strain S2V2 which inhibited the growth of pathogenic marine Vibrio spp. The aims of this research were to identify a new antibiotic-producing marine bacterium strain S2V2, and evaluate its
spectrum activity and pathogenic property. Analysis of 16S rDNA sequence placed strain S2V2 in the genus Pseudoalteromonas, but the sequence similarity was low (95.46%) implying the strain might be a new species in this genus. Strain S2V2 inhibited
the growth of 67.9% of 28 Vibrio strains tested. This strain inhibited V. alginolyticus, V. anguillarum, V. fluvialis, V. harveyi, V. metschnikovii, V. splendidus, V. ordalii, V. parahaemolyticus, and V. vulnificus, but inactive against V. campbellii, Aeromonas hydrophyla and Staphylococcus aureus. Strain S2V2 produced extracellular non proteinaceous antibacterial substances. The highest antibacterial activity was found
when strain S2V2 was cultured for 96 h in ZoBell broth medium. An artificial infection to post larvae of Lithopenaeus vanname indicated that strain S2V2 was a non pathogenic bacterium. Non pathogenic property and specific antibacterial activity against
a broad range of fish pathogenic marine Vibrio of strain S2V2 suggest that this strain is a prospective source of unique antibiotic and a potential biocontrol agent in
marine aquaculture. 相似文献
34.
The recently published review by Dreiza et al. (Cell Stress and Chaperones DOI ) dealing with the functional role of HSPB6 in muscle regulation is critically analyzed. Published data indicate that the
chaperone-like activity of HSPB6 is comparable with that of HSPB5 and that phosphorylation of HSPB6 does not affect its oligomeric
structure. Different hypotheses concerning the molecular mechanisms of HSPB6 action on smooth muscle contraction and on the
reorganization of the cytoskeleton are compared, and it is concluded that although HSPB6 is not a genuine actin-binding protein,
it can affect the actin cytoskeleton indirectly. Phosphorylated HSPB6 interacts with 14-3-3 and thereby displaces other binding
partners of 14-3-3; among them, certain phosphatases, protein kinases, and various actin-binding proteins, which can participate
in the reorganization of the actin cytoskeleton. In addition, HSPB6 seems to regulate the activity of certain protein kinases.
All of these processes are dependent on HSPB6 phosphorylation which in turn might be regulated by the formation of heterooligomeric
complexes of HSPB6 with other small heat shock proteins. 相似文献
35.
Tamal Krishna Paul Prof. Dr. Mohammad Abdul Jalil Dr. Md. Reazuddin Repon Md. Abdul Alim Tarekul Islam Sheikh Tamjidur Rahman Ayon Paul Mukitur Rhaman 《化学与生物多样性》2023,20(8):e202300510
Nanotechnology is gaining enormous attention as the most dynamic research area in science and technology. It involves the synthesis and applications of nanomaterials in diverse fields including medical, agriculture, textiles, food technology, cosmetics, aerospace, electronics, etc. Silver nanoparticles (AgNPs) have been extensively used in such applications due to their excellent physicochemical, antibacterial, and biological properties. The use of plant extract as a biological reactor is one of the most promising solutions for the synthesis of AgNPs because this process overcomes the drawbacks of physical and chemical methods. This review article summarizes the plant-mediated synthesis process, the probable reaction mechanism, and the colorimetric sensing applications of AgNPs. Plant-mediated synthesis parameters largely affect the surface plasmon resonance (SPR) characteristic due to the changes in the size and shape of AgNPs. These changes in the size and shape of plant-mediated AgNPs are elaborately discussed here by analyzing the surface plasmon resonance characteristics. Furthermore, this article also highlights the promising applications of plant-mediated AgNPs in sensing applications regarding the detection of mercury, hydrogen peroxide, lead, and glucose. Finally, it describes the future perspective of plant-mediated AgNPs for the development of green chemistry. 相似文献
36.
37.
Strains of the fish pathogen Enterococcus seriolicida were identified as agglutinating and non-agglutinating, according to their reaction with anti-serum raised against type strain YT-3 (ATCC49156). The non-agglutinating strains are highly pathogenic in contrast to agglutinating strains. A 96 kDa immunoprotective glycoprotein G1 antigen from non-agglutinating Ent. seriolicida strain SS91-014 (N) was purified and characterized. The purification procedure entailed extraction of antigen by glass bead agitation, 80% (NH4)(2)SO4 precipitation, gel filtration and electroelution. An immunofluorescence microscopy study using monoclonal antibody M3A5 raised against G1 antigen revealed that G1 antigen is present only on the cell surface of non-agglutinating strains. Therefore, the G1 antigen of virulent Ent. seriolicida could be a potential candidate for protective vaccine against enterococcosis in fish. 相似文献
38.
Ekram M. Saleh Raafat A. El-Awady Mervat A. Abdel Alim Abdel Hady A. Abdel Wahab 《Cell biochemistry and biophysics》2009,55(2):95-105
This study was designed to investigate the molecular changes that may develop during exposure of breast cancer cells to anticancer
agents and that may lead to acquired resistance. We used two breast cancer cell lines, a parental (MCF7/WT) and a doxorubicin-resistant
(MCF7/DOX) one. Cell survival, cell cycle distribution and RT-PCR expression level of genes involved in DNA damage response,
MDR1, GST and TOPOIIα were measured. MCF7/DOX cells were five-fold more resistant to doxorubicin (DOX) than the MCF7/WT cells.
DOX treatment causes arrest of MCF7/DOX cells in G1 and G2 phases of cell cycle whereas MCF7/WT cells were arrested in S-phase.
The molecular changes in both cell lines due to DOX treatment could be classified into: (1) the basal level of p53, p21, BRCA1,
GST and TOPOIIα mRNA was higher in MCF7/DOX than MCF7/WT. During DOX treatment, the expression level of these genes decreased
in both cell lines but the rate of down-regulation was faster in MCF7/WT than MCF7/DOX cells. (2) The expression level of
MDR1 was the same in both cell lines but 48 and 72 h of drug treatment, MDR1 disappeared in MCF7/WT but still expressed in
MCF7/DOX. (3) There was no change in the expression level of BAX, FAS and BRCA2 in both cell lines. Conclusively, after validation
in clinical samples, overexpression of genes like BRCA1, p53, p21, GST, MDR1 and TOPOIIα could be used as a prognostic biomarker
for detection of acquired resistance in breast cancer and as therapeutic targets for the improvement of breast cancer treatment
strategies. 相似文献
39.
40.
Suzannah J. Rihn Sam J. Wilson Nick J. Loman Mudathir Alim Saskia E. Bakker David Bhella Robert J. Gifford Frazer J. Rixon Paul D. Bieniasz 《PLoS pathogens》2013,9(6)
Genetic robustness, or fragility, is defined as the ability, or lack thereof, of a biological entity to maintain function in the face of mutations. Viruses that replicate via RNA intermediates exhibit high mutation rates, and robustness should be particularly advantageous to them. The capsid (CA) domain of the HIV-1 Gag protein is under strong pressure to conserve functional roles in viral assembly, maturation, uncoating, and nuclear import. However, CA is also under strong immunological pressure to diversify. Therefore, it would be particularly advantageous for CA to evolve genetic robustness. To measure the genetic robustness of HIV-1 CA, we generated a library of single amino acid substitution mutants, encompassing almost half the residues in CA. Strikingly, we found HIV-1 CA to be the most genetically fragile protein that has been analyzed using such an approach, with 70% of mutations yielding replication-defective viruses. Although CA participates in several steps in HIV-1 replication, analysis of conditionally (temperature sensitive) and constitutively non-viable mutants revealed that the biological basis for its genetic fragility was primarily the need to coordinate the accurate and efficient assembly of mature virions. All mutations that exist in naturally occurring HIV-1 subtype B populations at a frequency >3%, and were also present in the mutant library, had fitness levels that were >40% of WT. However, a substantial fraction of mutations with high fitness did not occur in natural populations, suggesting another form of selection pressure limiting variation in vivo. Additionally, known protective CTL epitopes occurred preferentially in domains of the HIV-1 CA that were even more genetically fragile than HIV-1 CA as a whole. The extreme genetic fragility of HIV-1 CA may be one reason why cell-mediated immune responses to Gag correlate with better prognosis in HIV-1 infection, and suggests that CA is a good target for therapy and vaccination strategies. 相似文献