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The defatted starch was dispersed in NaOH (1 M) and neutralized with HCl (1 M). The amylose 1-butanol complex is adsorbed on defatted cellulose powder in the solvent system containing acetate buffer (pH 4.8,0.1 M) + urea (2 M) + 1-butanol (8.5%, v/v). The complex adsorbed on cellulose powder is separated by centrifugation (2418 g). The sediment is washed with the solvent system-I to obtain the intermediate fraction. The adsorbed amylose is eluted with urea (2 M) in acetate buffer (pH 4.8, 0.1 M). The amylose, intermediate fraction and amylopectin were precipitated with ethanol, washed free of urea and air dried. They were characterized by determining their blue value and beta -amylolysis limit. 相似文献
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Sarvesh Adda T. P. Reddy P. B. Kavi Kishor 《In vitro cellular & developmental biology. Plant》1994,30(2):104-107
Summary Induction of somatic embryogenesis, shoot organogenesis, and subsequent plant regeneration in niger seem to be dependent on
genotype, choice of explant, and composition of media growth regulators. Two distinct regeneration protocols have been developed
for somatic embryogenesis and shoot organogenesis. Somatic embryogenesis was induced from epicotyls and cotyledonary explants
(9 to 35%) (but not from hypocotyls and roots) in presence of 2,4-dichlorophenoxyacetic acid, 2,4,5-trichlorophenoxyacetic
acid, and 2,4,5-trichlorophenoxypropionic acid. These embryos matured in MS medium containing Kinetin plus naphthalene acetic
acid (NAA), Kinetin plus Zeatin, and Kinetin plus abscisic acid (ABA). Matured embryos could be germinated on LS and MS basal
media without hormones. Non-embryogenic callus initiated on Linsmaier and Skoog’s (LS) medium from cotyledons of six
different genotypes produced shoots (9 to 32%) on Murashige and Skoog’s (MS) medium fortified with 6-benzylaminopurine
(BAP, 0.5 mg · liter−1), and BAP (1 mg · liter−1) plus NAA (0.1 mg · liter−1). These shoots were rooted with 100% frequency by using indole-3-acetic acid or NAA and transferred successfully to the soil. 相似文献
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L. Vijayalakshmi K. Naveen Kumar Kishor Palle Jong Dae Baek Abdallah A. A. Mohammed 《Luminescence》2023,38(9):1624-1631
Using the melt quenching technique, a lithium zinc borate glass (LZB) system with trivalent dysprosium ions (Dy3+) was synthesized, and the luminescence and lasing properties of these materials were examined for the generation of white light. Structural investigation through X-ray diffraction revealed that the prepared glass had an amorphous nature. The optimized glass containing 0.5 Dy3+ had a direct optical band gap of 2.782 eV and an indirect optical band gap of 3.110 eV. A strong excitation band at 386 nm (6H15/2→4I13/2) was recognized in the ultraviolet (UV) light region of its excitation spectrum. Emission bands could be seen in the photoluminescence spectrum at 659, 573, and 480 nm under the 386 nm excitation. These transitions of emission resembled electronic transitions such as (4F9/2→6H11/2), (4F9/2→6H13/2), and (4F9/2→6H15/2). In a pristine glass matrix, the higher intensity ratio of yellow to blue can result in the production of white light. The optimized Dy3+ ion concentration was observed to be 0.5 mol%. In addition, an analysis of lifetime decay was conducted for all synthesized glasses, and their decay trends were systematically investigated. Noticeably, we assessed the photometric parameters and found that they were close to the white light standard. Furthermore, a cytotoxicity study was carried out using lung fibroblast (WI-38) cell lines for the optimized 0.5Dy3+-doped LZB glass and it appeared to be noncytotoxic. It is clear from the results that the noncytotoxic LZB glass doped with 0.5 Dy3+ ions could be a suggestive choice for the manufacture of white light-emitting diodes and lasers using near-UVs. 相似文献
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Enhanced plant regeneration in grain and sweet sorghum by asparagine,proline and cefotaxime 总被引:7,自引:0,他引:7
Summary Cefotaxime ( 50 and 100 mg/1 ), a cephalosporin antibiotic and the amino acids asparagine and proline (200 mg/l) enhanced the production of embryogenic callus, increased the frequency of plant regeneration, and delayed the loss of regeneration potential in immature embryo-derived callus cultures ofSorghum bicolor (L.) Moench. Although these compounds did not promote callus induction or growth of callus, they influenced plant regeneration considerably in 10 low responding genotypes of grain and high anthocyanin containing sweet sorghums. 相似文献
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On exposure to visible light, riboflavin and lumiflavin produced reactive oxygen species such as singlet oxygen and superoxide radicals. The reaction was found to be time- and concentration-dependent. Both riboflavin and lumiflavin, upon illumination, showed mutagenic response in the umu test as well as in the Ames/Salmonella assay with Salmonella typhimurium TA102. The mutagenic response was partially abolished by superoxide dismutase while sodium azide did not have any effect. No mutagenicity was observed if the compounds were not illuminated. The results suggested the involvement of superoxide radicals in light-induced mutagenicity of riboflavin as well as lumiflavin. 相似文献
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P.G. Kale 《Mutation research》1980,72(2):177-186
Relative biological effectiveness of neutrons vs. X-rays in inducing crossing-over in males of D. melanogaster was investigated using 812 and 834 rad of neutrons and the same dose of X-rays. Crossing-over was induced in spermatocytes and spermatogonia of adults and pupae. Neutrons were 4 times more effective in spermatocytes of adults and their effectiveness in pupal spermatocytes was even more. Neutrons also induced more exchanges in spermatogonial cells including predefinitive spermatogonia. Higher effectiveness of neutrons can be attributed to their high linear energy transfer. 相似文献
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