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1.
Chemical investigation of the cave sponge Xestospongia sp. resulted in the isolation of three new polyacetylenic long chain compounds along with two known metabolites. The structures of the new metabolites were established by NMR and MS analyses. The antibacterial activity of the new metabolites was also evaluated. 相似文献
2.
Napin from mustard (Brassica juncea L.) is a seed storage protein consisting of two subunits linked through disulfide bonds and is predominantly helical in nature. Resistance to trypsin digestion and allergenicity limit its food applications. The role of disulfide linkages, electrostatic as well as hydrophobic interactions, in napin stability have been investigated through spectroscopic methods, employing different fluorescent probes and additives. The subunits are hydrophilic in nature and possess extended structure. With the addition of 0.5 M NaCl, the surface hydrophobicity of napin decreases, whereas the helical content increases by 25%. In the presence of NaCl, emission maximum shifts toward shorter wavelength and the Stern-Volmer constant decreases from 6.5 to 3.4 M-1, indicating compaction of napin. Na2SO4 has no significant effect on the structure due to the lack of a hydrophobic core. In the presence of monohydric alcohols and trifluoroethanol, there is an increase in ordered structure. These studies indicate that the structure of napin, which is hydrophilic in nature, is stabilized by electrostatic interactions, in addition to disulfide linkages. 相似文献
3.
Malted cereals are rich sources of alpha-amylase, which catalyzes the random hydrolysis of internal alpha-(1-4)-glycosidic bonds of starch, leading to liquefaction. Amylases play a role in the predigestion of starch, leading to a reduction in the water absorption capacity of the cereal. Among the three cereal amylases (barley, ragi, and jowar), jowar amylase is found to be the most thermostable. The major amylase from malted jowar, a 47 kDa alpha-amylase, purified to homogeneity, is rich in beta structure ( approximately 60%) like other cereal amylases. T(m), the midpoint of thermal inactivation, is found to be 69.6 +/- 0.3 degrees C. Thermal inactivation is found to follow first-order kinetics at pH 4.8, the pH optimum of the enzyme. Activation energy, E(a), is found to be 45.3 +/- 0.2 kcal mol(-)(1). The activation enthalpy (DeltaH), entropy (DeltaS*), and free energy change (DeltaG) are calculated to be 44.6 +/- 0.2 kcal mol(-)(1), 57.1 +/- 0.3 cal mol(-)(1) K(-)(1), and 25.2 +/- 0.2 kcal mol(-)(1), respectively. The thermal stability of the enzyme in the presence of the commonly used food additives NaCl and sucrose has been studied. T(m) is found to decrease to 66.3 +/- 0.3, 58.1 +/- 0.2, and 48.1 +/- 0.5 degrees C, corresponding to the presence of 0.1, 0.5, and 1 M NaCl, respectively. Sucrose acts as a stabilizer; the T(m) value is found to be 77.3 +/- 0.3 degrees C compared to 69.6 +/- 0.3 degrees C in the control. 相似文献
4.
The use of biopesticides compatible with chemical pesticides is recommended in pest management as an effective and ecologically sound strategy. The entomopathogenic fungus Beauveria bassiana (Balsamo) Vuill, which is used as a biopesticide, was found to exhibit and lose tolerance to two organophosphorus insecticides widely used in Indian fields. The pattern of response is similar to the esterase-mediated organophosphate tolerance in aphids achieved through esterase gene duplication. Therefore the role of esterase in the tolerance exhibited by isolates of B. bassiana to the organophosphate, monocrotophos, was studied. Both the total soluble protein content and esterase activity were found to increase significantly in B. bassiana cultures that were able to grow in the presence of monocrotophos. With the hitherto established linkage between esterase overproduction and organophosphate tolerance in insects and the observed similarity in response of the insects and B. bassiana to the chemical, it is concluded that tolerance to monocrotophos in B. bassiana may be due to a mechanism similar to that operating in insects. Habituation of the fungus to monocrotophos to initiate expression of esterase gene may help in achieving compatibility between the two. 相似文献
5.
Kadanthottu Sebastian Joseph Sushma Bolla Kavita Joshi Medha Bhat Krupa Naik Sridevi Patil Sreevani Bendre Brunda Gangappa Vidya Haibatti Shivanand Payamalle Smita Shinde Yaser Hassan Dewir Hosakatte Niranjana Murthy 《Erwerbs-Obstbau》2017,59(3):195-202
African mangosteen (Garcinia livingstonei T. Anderson) is native to Africa and is exotic to other parts of the world. It is a fruit bearing tree with multiple uses. This study was purposed to determine, by analysis, the chemical compositions and nutritive value of the fruits of African mangosteen. Proximate compositions varied with the portions such as epicarp, mesocarp, endocarp and seed tested. All fruit portions contained carbohydrate (37.67–95.02%) and crude protein (0.65–31.76%) as their major components. Moisture (0.45–3.42%), crude fat (1.23–19.55%), crude fiber (2.93–21.13%) and ash (1.76–5.44%) were also found at different levels, depending upon the portions. All portions of fruit were rich in macro and micro elements. The fruits also possessed phenolics (174.02–10.725?mg GAE per g), flavonoid (19.25 to 99.98?µg QE per g) and alkaloid (1.56 to 9.49?mg/kg) contents. The constitution of tannins and oxalate which contribute towards the anti-nutritive value was also low, thus making the fruits beneficial for consumption. Quality attributes like relative amount of oleic acid, total unsaturated fatty acid, acid value, free fatty acid, peroxide value and iodine value showed that the seed oil of African mangosteen can become one among the oleic acid based vegetable oils for consumption. 相似文献
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7.
Roy P. Koteeswaran A. Sridevi P. Venugopalan A.T. 《Tropical animal health and production》1998,30(1):31-35
Seroconversion of 3 lentogenic commercial Newcastle disease (ND) vaccines and experimental V4 vaccines was compared based on the haemagglutination inhibition (HI) test against ND. It was found that for primary vaccination all the vaccines produced similar response but for secondary vaccinations V4 and LaSota were better than RDVF. Eighty-five samples each of serum, tears and feather pulp were collected from respective birds and antibody assessment was done against ND by HI test. The geometric mean HI titres (GMT) of serum samples were highest followed by tears and feather pulp samples before vaccination and 3 weeks after vaccination by oculonasal route and the difference was statistically significant (p<0.01). Three weeks after booster vaccination by oculonasal route, however, the GMT of serum samples were highest followed by feather pulp and tears samples. The ease of collection of feather pulp samples and their role in ND serology is discussed. 相似文献
8.
Sridevi Ankisetty Shabana I. Khan Bharathi Avula Deborah Gochfeld Ikhlas A. Khan Marc Slattery 《Marine drugs》2013,11(11):4478-4486
Chemical investigation of the tunicate Trididemnum solidum resulted in the isolation of two new chlorinated compounds belonging to the didemnin class, along with two known compounds didemnin A and didemnin B. The structural determination of the compounds was based on extensive NMR and mass spectroscopic analysis. The isolated compounds 1–4 were tested for their anti-inflammatory activity using in vitro assays for inhibition of inducible nitric oxide synthase (iNOS) and nuclear factor-kappa B (NF-κB) activity. The anti-cell proliferative activity of the above compounds was also evaluated against four solid tumor cell lines. 相似文献
9.
Reciprocal crosses were made between Brassica carinata and its related species Sinapis alba. Pollen germination studies indicated the presence post-fertilization barriers in both ways. Sequential ovary–ovule culture
helped to realize the intergeneric hybrids from the cross S. alba × B. carinata. The F1 obtained was confirmed as a hybrid based on morphology, cytology and isozyme studies. The hybrid was backcrossed to its male
parent and obtained BC1 seeds, which were used to raise BC1 generation. The BC1 generation plants were further backcrossed to B. carinata in order to develop alloplasmic lines. 相似文献
10.
Rama Rao S.V. Praharaj N.K. Reddy M.R. Sridevi B. 《Veterinary research communications》1999,23(6):323-336
Immune competence, resistance to Escherichia coli and growth were measured in female chicks of broiler male parent lines from four different commercial sources. These chicks were fed with three levels of dietary crude protein (CP) from day-old. The protein contents in the diets were 18%, 20.5% and 23%; these diets are referred to as the low-, medium- and high-protein diets, respectively. There was a significant genotype by dietary protein interaction for body weight at 35 days of age but not at 14 or 28 days of age. At 14 days of age, the chicks fed on the high-protein diet weighed significantly more than those fed on the low-protein diet, but there were no differences between the chicks fed on the medium- and low-protein diets. The influence of CP content on body weight had disappeared by 28 days of age. There were significant differences between the genotypes in antibody production in response to sheep red blood cell (SRBC) inoculation, but no such differences were observed between the chicks fed the different levels of dietary protein. Chicks fed on the high-protein diet had lower lesion scores following E. coli inoculation than those fed on the low-protein diet. There were also significant differences in lesion scores among the genotypes. Genotypes with heavier body weights had significantly higher lesion scores and lower antibody titres than those with less body weight. Also, genotypes of lower body weight had a greater cutaneous basophilic hypersensitivity response to phytohaemaglutinin-P inoculation, and a better humoral response against SRBC and a lower heterophil to lymphocyte ratio. 相似文献