Abstract We have investigated the use of alkylamines as fast cleavage and deprotection reagents for the solid phase synthesis of oligonucleotides and found methylamine/ammonium hydroxide (or methylamine) as an efficient reagent. The transamination side product formed with the commonly used dCbz has been eliminated by the use of dCAc phosphoramidite. This system has successfully been used in the synthesis of oligonucleotides and oligonucleoside phosphorothioates. DMT dCAc hydrogen phosphonate and DMT ribo CAc-2′-O Me phosphoramidite also have been prepared and used in the synthesis of oligonucleotides. 相似文献
A well-organized protocol has been developed for high frequency root germination from the seed of Canavalia ensiformis on Murashige and Skoog (MS) medium. Surprisingly, the seeds that were grown on the MS medium having no growth hormone showed
the best response. Roots of 30 days old aseptic seedling were homogenized and a lectin from them was purified on Sephadex
G-50 affinity column. The finding that final product is a pure lectin was confirmed by specific hemagglutinating property.
The final root lectin yield was 0.6% and eluted as a single peak. Root lectin specific activity was 50 times more than the
seed lectin. Sugar specificity activity by hemagglutination-inhibition assay indicated that lectin belongs to glucose/mannose-specific
group. Interestingly, the lectin was found to be 25 kDa, similar to molecular mass of Concanavalin A purified from seed of
C. ensiformis, as revealed by SDS–PAGE. Thus, Concanavalin A from either source can be used for development of transgenic crops that are
capable of expressing lectin gene and hence can efficiently perform biological nitrogen fixation by giving rise to nodules
in their root. The advantage of this method is that purification of Concanavalin A in tissue culture conditions is easier,
handy and is less time consuming. 相似文献
Ocimum basilicum L. var. purpurascens is an enriched reservoir of pharmaceutically important compounds with plenty of health and therapeutic attributes such as phenolic acids and anthocyanins. However, the inefficient production of aforementioned metabolites in wild has restricted its commercial utilization. Herein, commercially viable phytochemicals have been enhanced through elicitation of in-vitro cultures of O. basilicum using yeast extract.The impact of various concentrations (YE 1 mg/L,YE 10 mg/L, YE 25 mg/L, YE 50 mg/L, YE 100 mg/L, YE 200 mg/L and YE 400 mg/L) of yeast extract on biomass accumulation, phytochemical production, and antioxidant activities were assessed in callus cultures. Moderate concentration of yeast extract (100 mg/L) enhanced biomass accumulation i.e. fresh weight (FW 216.28 g/L) and dry weight (DW 15.49 g/L) up to 1.5 folds as compared to control (FW 167.14 g/L and DW 10.25 g/L). Similarly, yeast extract (100 mg/L) increased total phenolic and flavonoid contents as well as enhanced antioxidant activities such as ABTS (2,2 azinobis 3-ethylbenzthiazoline-6-sulphonic acid), FRAP (ferric reducing antioxidant power) and DPPH (2,2-diphenyl-1-picryhydrazyl). High performance liquid chromatography (HPLC) analysis was elucidated for further phytochemical investigation. HPLC analysis showed an increase of almost 1.9 folds as compared to control in rosmarinic acid (15.19 mg/g DW), chicoric acid (2.13 mg/g DW), peonidin (2.70 mg/g DW) and cyanidin (1.57 mg/g DW). Likewise, 1.8 fold and 2.4 folds increase was observed in eugenol essential oils (0.25 mg/g DW) and chavicol (0.037 mg/g DW), respectively. For cellular antioxidant activity, reactive oxygen specie or reactive nitogen specie (ROS/RNS) was induced in yeast cells and the effect of O. basilicum callus culture was further investigated in stressed yeast cells. A positive correlation exists between the antioxidant activities, TPC and TFC analysis. In short, these results showed that yeast extract could act as an efficient elicitor to enhance pharmacologically important metabolites in callus cultures of Ocimum basilicum.
The interaction of reducing carbohydrates with proteins leads to a cascade of reactions that are known as glycation or Maillard reactions that results in the formation of advanced glycation end products. We studied the impact of incubation with various sugars for 4 weeks on the behaviour of human serum albumin incubation using CD, fluorescence, UV?CVis spectrophotometry and polyacrylamide gel electrophoresis. Three weeks of incubation of human serum albumin with sugars resulted in the formation of an intermediate state with negative CD peaks at 222 and 208 nm characteristic of ??-helix. The form also retained tertiary contacts but with altered tryptophan environment and high ANS binding indicative of molten globule state. Further incubation of human serum albumin for 4 weeks resulted in the formation of an intermediate form with negative CD peak at 217 nm, characteristic of ??-sheet, decreased ANS fluorescence and increased thioflavin T fluorescence characteristic of an aggregated state. Prolonged exposure of human serum albumin to reducing sugars thus exerts greater deleterious effects on its structure and formation of aggregates. 相似文献
Triacontanol (TRIA) has been realized as a potent plant growth promoting substance for a number of agricultural and horticultural
crops. Out of a large number of essential oil bearing plants, mint (Mentha arvensis L.) constitutes the most important source of therapeutic agents used in the alternative systems of medicine. The mint plant
has marvelous medicinal properties. In view of enhancing growth, yield and quality of this medicinally important plant, a
pot experiment was conducted according to simple randomized block design. The experiment was aimed at studying the effect
of four concentrations of TRIA (10−0, 10−7, 10−6 and 10−5 M) on the performance of mint with regard to growth and other physiological attributes, crop yield and quality attributes
and the yield and contents of active constituents of the plant. The growth and other physiological parameters as well as yield
and quality attributes were studied at 100 and 120 DAP. The foliar application of TRIA at 10−6 M concentration significantly enhanced most of the growth and other physiological attributes, crop herbage yield and the
yield and content of active constituents (menthol, l-methone, isomenthone and menthyl acetate) of mint at both the stages. However, the next higher concentration of TRIA (10−5 M) exhibited slightly negative effect and did not further increase the values of the attributes studied, but it proved significantly
better than the control. Application of TRIA significantly enhanced the yield and content of all the active constituents determined
by GLC technique. 相似文献
This research study is mainly focused to evaluate the anti-parasitic, insecticidal, cytotoxic and anti-alzheimer potential of various leaf extracts of Ajuga bracteosa Wallich ex Bentham. 04 different extracts were prepared using solvent of different polarity to determine the best candidate for potent bioactivity i.e. n-hexane (NH), Ethyl acetate (EA), Ethanol (EL) and Chloroform (CH). Concentrations of each extracts were made specified for all activities. All extracts were exploited for broad range of biomedical applications including leishmaniasis, in vitro anti-Alzheimer, insecticidal and cytotoxic studies. Our results showed that A. bracteosa n-hexane extract was highly active against Leishmania Tropica with significant inhibition of 58 ± 1.61 for promastigote and 63 ± 2.29 for amastigote at 1000 μg/mL. Furthermore, promising anti-alzheimer activity acetylcholinesterase (AChE) 46 ± 0.83 and butrylcholineterase (BChE) 49 ± 1.17 was noted for n-hexane. The insecticidal potential of these extracts were test against five different insects (Rhyzopertha dominica, Trogoderma granarium, Tribolium castaneum, Sitophilus oryze, and Callosobruchus analis). The higest mortality rate of insecticidal activity was recorded by n-hexane followed by Ethyl acetate whereas ethanol extract was found to be less effective against all the test species. Significant cytotoxic potential of each plant sample against Artemiasalina thus aware us for further detailed research to find out novel drugs. Based on our results we believe that Ajuga bracteosa could be used to develop as a potential botanical insecticide against different insect and pests, such as aphids as well as an excellent source for the compound isolation as anti-tumor agent. 相似文献
International Microbiology - Gut microbiota has become a new therapeutic target in the treatment of inflammatory Bowel Disease (IBD). Probiotics are known for their beneficial effects and have... 相似文献