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51.
Lawo NC Mahon RJ Milner RJ Sarmah BK Higgins TJ Romeis J 《Applied and environmental microbiology》2008,74(14):4381-4389
The use of genetically modified (Bt) crops expressing lepidopteran-specific Cry proteins derived from the soil bacterium Bacillus thuringiensis is an effective method to control the polyphagous pest Helicoverpa armigera. As H. armigera potentially develops resistance to Cry proteins, Bt crops should be regarded as one tool in integrated pest management. Therefore, they should be compatible with biological control. Bioassays were conducted to understand the interactions between a Cry2Aa-expressing chickpea line, either a susceptible or a Cry2A-resistant H. armigera strain, and the entomopathogenic fungus Metarhizium anisopliae. In a first concentration-response assay, Cry2A-resistant larvae were more tolerant of M. anisopliae than susceptible larvae, while in a second bioassay, the fungus caused similar mortalities in the two strains fed control chickpea leaves. Thus, resistance to Cry2A did not cause any fitness costs that became visible as increased susceptibility to the fungus. On Bt chickpea leaves, susceptible H. armigera larvae were more sensitive to M. anisopliae than on control leaves. It appeared that sublethal damage induced by the B. thuringiensis toxin enhanced the effectiveness of M. anisopliae. For Cry2A-resistant larvae, the mortalities caused by the fungus were similar when they were fed either food source. To examine which strain would be more likely to be exposed to the fungus, their movements on control and Bt chickpea plants were compared. Movement did not appear to differ among larvae on Bt or conventional chickpeas, as indicated by the number of leaflets damaged per leaf. The findings suggest that Bt chickpeas and M. anisopliae are compatible to control H. armigera. 相似文献
52.
Sarmah Bidyut K. Moore Andrew Tate Walter Molvig Lisa Morton Roger L. Rees David P. Chiaiese Pasquale Chrispeels Maarten J. Tabe Linda M. Higgins T.J.V. 《Molecular breeding : new strategies in plant improvement》2004,14(1):73-82
We describe a robust and reproducible Agrobacterium-mediated chickpea transformation method based on kanamycin selection, and its use to introduce the bean AI1 gene into a desi type of chickpea. Bean AI1 was specifically expressed in the seeds, accumulated up to 4.2% of seed protein and was processed to low molecular weight polypeptides as occurs in bean seeds. The transgenic protein was active as an inhibitor of porcine -amylase in vitro. Transgenic chickpeas containing -AI1 strongly inhibited the development of Callosobruchus maculatus and C. chinensis (Col. : Bruchidae) in insect bioassays. 相似文献
53.
The taste of polycose in hamsters 总被引:2,自引:2,他引:0
Hamsters show a preference for Polycose, a mixture of starch-derived
glucose polymers, that is as strong as their preference for sucrose.
However, in the hamster, taste aversions to Polycose may be less easily
acquired than taste aversions to sucrose and the qualitative aspects of
Polycose are unknown in this species. In order to examine the taste of
Polycose in the hamster, we utilized a taste-aversion protocol with two
conditioning trials. Animals were trained to avoid one of three different
conditioning stimuli: 50 mM sucrose, 100 mM Polycose and a mixture of 50 mM
sucrose with 100 mM Polycose. Control animals were conditioned with
deionized water. After the second conditioning trial, generalization
testing began for the three conditioning stimuli plus 3 mM citric acid, 300
mM KCI and 30 mM NaCl. The results showed that aversions to Polycose,
sucrose or the Polycose/sucrose mixture cross- generalized, demonstrating
that Polycose and sucrose share a common taste percept in the hamster. None
of the aversions generalized to NaCl, citric acid or KCI. In addition,
comparisons among the patterns of taste generalizations indicated that the
tastes of Polycose and sucrose also had distinct qualitative components.
Finally, although the taste of 100 mM Polycose was more salient than the
taste of 50 mM sucrose, the taste of sucrose could still be detected in a
mixture with Polycose.
相似文献
54.
P. K. Mukherjee A. N. Mukhopadhyay D. K. Sarmah S. M. Shrestha 《Journal of Phytopathology》1995,143(5):275-279
An isolate of Trichoderma harzianum which is less effective than G. virens in suppressing S. rolfsii and R. solani was compared with G. virens for various mechanisms of antagonism in vitro, viz., antagonism in dual culture/hyphal parasitism, parasitism of sclerotia and antibiosis. G. virens and T. harzianum were equally effective in parasitizing the hyphae of R. solani. Only T. harzianum parasitized the hyphae of S. rolfsii, and the two antagonists were comparable with respect to antibiosis on the test pathogens. However, G. virens readily parasitized the sclerotia of the test pathogens and was found to be more effective than T. harzianum in destroying the sclerotia. Under SEM, G. virens was found to colonize, penetrate, and sporulate inside the sclerotia of the test pathogens.Parasitism of sclerotia is suggested as the principal mechanism of biological control of S. rolfsii and R. solani by G. virens. 相似文献
55.
Nipon Sarmah D. Revathi G. Sheelu K. Yamuna Rani S. Sridhar V. Mehtab C. Sumana 《Biotechnology progress》2018,34(1):5-28
Lipases are the industrially important biocatalysts, which are envisioned to have tremendous applications in the manufacture of a wide range of products. Their unique properties such as better stability, selectivity and substrate specificity position them as the most expansively used industrial enzymes. The research on production and applications of lipases is ever growing and there exists a need to have a latest review on the research findings of lipases. The present review aims at giving the latest and broadest overall picture of research and development on lipases by including the current studies and progressions not only in the diverse industrial application fields of lipases, but also with regard to its structure, classification and sources. Also, a special emphasis has been made on the aspects such as process optimization, modeling, and design that are very critical for further scale‐up and industrial implementation. The detailed tabulations provided in each section, which are prepared by the exhaustive review of current literature covering the various aspects of lipase including its production and applications along with example case studies, will serve as the comprehensive source of current advancements in lipase research. This review will be very useful for the researchers from both industry as well as academia in promoting lipolysis as the most promising approaches to intensified, greener and sustainable processes. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:5–28, 2018 相似文献
56.
Mihir Rabha Sumita Acharjee Bidyut Kumar Sarmah 《World journal of microbiology & biotechnology》2018,34(7):103
An agriculturally important insecticidal bacterium, Bacillus thuringiensis have been isolated from the soil samples of various part of Assam including the Kaziranga National Park. Previously, the isolates were characterized based on morphology, 16S rDNA sequencing, and the presence of the various classes’ crystal protein gene(s). In the present study, the phylogenetic analysis of a few selected isolates was performed by an unambiguous and quick method called the multiple locus sequence typing (MLST). A known B. thuringiensis strain kurstaki 4D4 have been used as a reference strain for MLST. A total of four the MLST locus of housekeeping genes, recF, sucC, gdpD and yhfL were selected. A total of 14 unique sequence types (STs) was identified. A total number of alleles identified for the locus gdpD and sucC was 12, followed by locus yhfL was 11, however, only 6 alleles were detected for the locus recF. The phylogenetic analysis using MEGA 7.0.26 showed three major lineages. Approximately, 87% of the isolates belonged to the STs corresponding to B. thuringiensis, whereas two isolates, BA07 and BA39, were clustered to B. cereus. The isolates were also screened for the diversity of vegetative insecticidal protein (vip) genes. In all, 8 isolates showed the presence of vip1, followed by 7 isolates having vip2 and 6 isolates for vip3 genes. The expression of Vip3A proteins was analyzed by western blot analyses and expression of the Vip3A protein was observed in the isolate BA20. Thus, the phylogenetic relationship and diversity of Bt isolates from Assam soil was established based on MLST, in addition, found isolates having vip genes, which could be used for crop improvement. 相似文献
57.
Sarmah JK Mahanta R Bhattacharjee SK Mahanta R Biswas A 《International journal of biological macromolecules》2011,49(3):390-396
Natural polysaccharides, due to their outstanding merits, have received more and more attention in the field of drug delivery. In the present study tamoxifen citrate, TMX (a non-steroidal antiestrogenic drug) loaded guar gum nanoparticles, GG NPs, crosslinked with glutaraldehyde were prepared for treatment of breast cancer. An oil in water (o/w) emulsion polymer cross-linking method was employed for preparation of blank and drug loaded sustained release nature biodegradable nanoparticles. Prepared nanoparticles were characterized by morphology in scanning electron microscope (SEM), size distribution in transmission electron microscope (TEM), TMX loading by high performance liquid chromatography (HPLC) and in vitro drug release characteristics. An overall sustained release of the drug from the biodegradable nanoparticles was observed in in vitro release studies. The release of TMX from GG NPs was found to be effected by guar gum and glutaraldehyde concentration. Regression coefficient (R2) analysis suggested that the predominant mechanism behind the drug release from the nanoparticles was time dependent release and diffusion. In vivo studies on female albino mice demonstrated maximum uptake of the drug by mammary tissue after 24 h of administration with drug loaded guar gum nanoparticles in comparison with that with the tablet form of the drug. These findings demonstrate that controlled release of TMX from GG NPs could be a potential alternative pharmaceutical formulation in passive targeting of TMX in breast cancer treatments. 相似文献
58.
Prabalee Sarmah Ramendra Nath Sarma 《Molecular breeding : new strategies in plant improvement》2011,27(1):115-118
Calamus tenuis (Roxb.), a versatile, dioecious rattan species predominant in northeast India, has emerged as an economical material for
light furniture and cottage industries. For the genetic improvement of the species, it is essential to be able to recognize
male and female plants at the seedling stage. Screening of genomic DNA with inter-simple sequence repeat (ISSR) primers was
used to discover sex-specific polymerase chain reaction (PCR) amplification products. Thirty ISSR primers were screened on
female and male C. tenuis plants from five different provinces of Assam, India. A putative female-specific marker was identified. The applicability
of ISSR-PCR analysis for development of sex-linked molecular markers in Calamus is discussed. 相似文献
59.
BK Clapperton TD Day DKJ Morgan F Huddart N Cox LR Matthews 《New Zealand journal of zoology.》2013,40(2):104-118
Repellents used to reduce by-kill of birds during pest control must not compromise acceptance by target species. Two repellents combined, anthraquinone (AQ; 0.4 g kg?1) and d-pulegone (DP; 1.0) did not reduce the palatability of blue-coloured carrot baits to laboratory rats (Rattus norvegicus); nor did DP (2.0). Green-coloured carrot baits coated with AQ, DP or AQ + DP were taken from bait stations by wild possums (Trichosurus vulpecula) and rats. Toxic (1080) bait coated with AQ (0.4) and peanut oil (0.1) had reduced palatability but was accepted by laboratory rats. However, laboratory rats did not consume enough baits coated with AQ and bacon, peanut butter, cinnamon or DP to be killed. Anthraquinone (0.4 or 0.8) plus cinnamon and DP (0.5) did not affect palatability or lethality to captive ship rats (R. rattus) or possums. Anthraquinone and DP as surface coatings on baits are therefore acceptable to possums and possibly rats, at concentrations that deter some bird species. 相似文献
60.
Seifan Mostafa Sarmah Ajit K. Ebrahiminezhad Alireza Ghasemi Younes Samani Ali Khajeh Berenjian Aydin 《Applied microbiology and biotechnology》2018,102(5):2167-2178
Applied Microbiology and Biotechnology - Immobilization has been reported as an efficient technique to address the bacterial vulnerability for application in bio self-healing concrete. In... 相似文献