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Hemavathi Maduraiveeran Kavitha Raja Arulvasu Chinnasamy 《Saudi Journal of Biological Sciences》2021,28(3):1954-1961
This study aimed to investigate the antiproliferative and antioxidant properties of crude venom from the nematocyst of Jellyfish Acromitus flagellates on human lung cancer (A549) and liver cancer (HepG2) cell lines. The prepared crude venom was subjected to analyses of the biochemical constituents, protein profiles, antioxidant and anticancer activities by standard methods. The extracted venom was pale-yellow in color and viscous/sticky. The biochemical composition such as, protein (1.547 mg/ml), lipid (0.039 mg/ml) and carbohydrate (0.028 mg/ml) was estimated. Protein profiles were determined by SDS PAGE, the result revealed that the molecular weight range from 205 ? 3.5 kDa. The free radical scavenging activity was analyzed by the reducing potential (56.36%), DPPH (72.47%), hydroxyl (68.50%), superoxide anion (65.75%), and nitric oxide (33.04%). The cell viability was observed by using different concentrations (20 to 100 µg/ml) of crude venom on A549 and HepG2 cancer cell lines and the IC50 values were recorded in (60 μg/ml and 40 μg/ml) respectively, while it had none cytotoxic effects on Vero cell line up to the concentration of 90 μg/ml. These results suggest that crude venom from nematocyst of A. flagellatus possesses anti-cancer activity and able to develop novel drugs on marine-derived compounds. 相似文献
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Hemavathi Chandrama Prakash Upadhyaya Ko Eun Young Nookaraju Akula Hyun soon Kim Jeon Jae Heung Oh Man Oh Chenna Reddy Aswath Se Chul Chun Doo Hwan Kim Se Won Park 《Plant science》2009,177(6):659-667
Vitamin C (ascorbic acid) is an essential component for collagen biosynthesis and also for the proper functioning of the cardiovascular system in humans. Unlike most of the animals, humans lack the ability to synthesize ascorbic acid on their own due to a mutation in the gene encoding the last enzyme of ascorbate biosynthesis. As a result, vitamin C must be obtained from dietary sources like plants. In this study, we have developed transgenic potato plants (Solanum tuberosum L. cv. Taedong Valley) over-expressing strawberry GalUR gene under the control of CaMV 35S promoter with increased ascorbic acid levels. Integration of the GalUR gene in the plant genome was confirmed by PCR and Southern blotting. Ascorbic acid (AsA) levels in transgenic tubers were determined by high-performance liquid chromatography (HPLC). The over-expression of GalUR resulted in 1.6–2-fold increase in AsA in transgenic potato and the levels of AsA were positively correlated with increased GalUR activity. The transgenic lines with enhanced vitamin C content showed enhanced tolerance to abiotic stresses induced by methyl viologen (MV), NaCl or mannitol as compared to untransformed control plants. The leaf disc senescence assay showed better tolerance in transgenic lines by retaining higher chlorophyll as compared to the untransformed control plants. Present study demonstrated that the over-expression of GalUR gene enhanced the level of AsA in potato tubers and these transgenics performed better under different abiotic stresses as compared to untransformed control. 相似文献
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The synthesis of purine nucleosides capable of making the guanidinium linkage is described for the first time starting from the corresponding 2'-deoxynucleosides. The positively charged mixed base DNG oligomer containing guanine was synthesized on solid-phase using CPG as support from 3' to 5' direction using the precursor building block nucleosides. 相似文献
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Tangential flow ultrafiltration with a polyethersulfone (100 kDa) membrane was used for the purification and concentration
of β-glycosidases (β-galactosidase and β-glucosidase) from aqueous extract of barley. The performances of mode 1 (concentration
followed by diafiltration) and mode 2 (diafiltration followed by concentration) were compared. In mode 1 activity recoveries
of 91.44 and 88% as well as purifications of 1.84 and 1.77-fold for β-galactosidase and β-glucosidase, respectively, were
obtained in a total processing time of about 9 h. In mode 2 activity recoveries of 95.68 and 91.76% with purifications of
4.56 and 4.38-fold for β-galactosidase and β-glucosidase, respectively, were obtained in a total processing time of about
6 h. The removal of total carbohydrates and protein was 56.74 and 50.73%, respectively, in mode 1, whereas it was 81.46 and
79.04%, respectively, in mode 2. The diafiltration volume and volume concentration of 3 were maintained in both mode 1 and
2. Flux decline was severe in mode 1 and led to a long processing time of about 9 h. These results indicate that mode 2 was
better than mode 1 for purification of β-glycosidases. 相似文献
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Gopal H Hassan HK Rodríguez-Pérez MA Toé LD Lustigman S Unnasch TR 《PLoS neglected tropical diseases》2012,6(6):e1712
Background
Entomological surveys of Simulium vectors are an important component in the criteria used to determine if Onchocerca volvulus transmission has been interrupted and if focal elimination of the parasite has been achieved. However, because infection in the vector population is quite rare in areas where control has succeeded, large numbers of flies need to be examined to certify transmission interruption. Currently, this is accomplished through PCR pool screening of large numbers of flies. The efficiency of this process is limited by the size of the pools that may be screened, which is in turn determined by the constraints imposed by the biochemistry of the assay. The current method of DNA purification from pools of vector black flies relies upon silica adsorption. This method can be applied to screen pools containing a maximum of 50 individuals (from the Latin American vectors) or 100 individuals (from the African vectors).Methodology/Principal Findings
We have evaluated an alternative method of DNA purification for pool screening of black flies which relies upon oligonucleotide capture of Onchocerca volvulus genomic DNA from homogenates prepared from pools of Latin American and African vectors. The oligonucleotide capture assay was shown to reliably detect one O. volvulus infective larva in pools containing 200 African or Latin American flies, representing a two-four fold improvement over the conventional assay. The capture assay requires an equivalent amount of technical time to conduct as the conventional assay, resulting in a two-four fold reduction in labor costs per insect assayed and reduces reagent costs to $3.81 per pool of 200 flies, or less than $0.02 per insect assayed.Conclusions/Significance
The oligonucleotide capture assay represents a substantial improvement in the procedure used to detect parasite prevalence in the vector population, a major metric employed in the process of certifying the elimination of onchocerciasis. 相似文献7.
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Enhanced ascorbic acid accumulation in transgenic potato confers tolerance to various abiotic stresses 总被引:2,自引:0,他引:2
Hemavathi Chandrama Prakash Upadhyaya Nookaraju Akula Ko Eun Young Se Chul Chun Doo Hwan Kim Se Won Park 《Biotechnology letters》2010,32(2):321-330
l-Ascorbic acid (Vitamin C, AsA) is an important component of human nutrition. Plants and several animals can synthesize their
own ascorbic acid, whereas humans lack the gene essential for ascorbic acid biosynthesis and must acquire from their diet.
In the present study, we developed transgenic potato (Solanum tuberosum L. cv. Taedong Valley) over-expressing l-gulono-γ-lactone oxidase (GLOase gene; NCBI Acc. No. NM022220), isolated from rat cells driven by CaMV35S constitutive promoter
that showed enhanced AsA accumulation. Molecular analyses of four independent transgenic lines performed by PCR, Southern
and RT-PCR revealed the stable integration of the transgene in the progeny. The transformation frequency was ca. 7.5% and
the time required for the generation of transgenic plants was 6–7 weeks. Transgenic tubers showed significantly enhanced AsA
content (141%) and GLOase activity as compared to untransformed tubers. These transgenics were also found to withstand various
abiotic stresses caused by Methyl Viologen (MV), NaCl or mannitol, respectively. The T1 transgenic plants exposed to salt stress (100 mM NaCl) survived better with increased shoot and root length when compared
to untransformed plants. The elevated level of AsA accumulation in transgenics was directly correlated with their ability
to withstand abiotic stresses. These results further demonstrated that the overexpression of GLOase gene enhanced basal levels of AsA in potato tubers and also the transgenics showed better survival under various abiotic
stresses. 相似文献
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Upadhyaya CP Venkatesh J Gururani MA Asnin L Sharma K Ajappala H Park SW 《Biotechnology letters》2011,33(11):2297-2307
Salt-tolerance was studied in transgenic potato. It was conferred by overexpression of ascorbate pathway enzyme (d-galacturonic acid reductase, GalUR). As genetic engineering of the GalUR gene in potato enhances its ascorbic acid content (l-AsA), and subsequently plants suffered minimal oxidative stress-induced damage, we now report on the comprehensive aptness
of this engineering approach for enhanced salt tolerance in transgenic potato (Solanum tuberosum L. cv. Taedong Valley). Potatoes overexpressing GalUR grew and tuberized in continuous presence of 200 mM of NaCl. The transgenic plants maintained a higher reduced to oxidized
glutathione (GSH:GSSG) ratio together with enhanced activity of glutathione dependent antioxidative and glyoxalase enzymes
under salinity stress. The transgenics resisted an increase in methylglyoxal that increased radically in untransformed control
plants under salinity stress. This is the first report of genetic engineering of ascorbate pathway gene in maintaining higher
level of GSH homeostasis along with higher glyoxalase activity inhibiting the accumulation in methylglyoxal (a potent cytotoxic
compound) under salt stress. These results suggested the engineering of ascorbate pathway enzymes as a major step towards
developing salinity tolerant crop plants. 相似文献
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