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111.
Mariyappan Vaithiyalingam Dr. Ramasamy Mohan Kumar Dr. Chinnaperumal Kamaraj Vimal Sugumar Nandhagopal Manivannan Shine Kadaikunnan Gajanan Ghodake 《化学与生物多样性》2023,20(6):e202300315
Citral ( 1a ), a bioactive component of Cymbopogon citratus (lemongrass) could be isolated and semi-synthetic analogs synthesized with improved therapeutic properties. Herein we first report describes citral ( 1a ) as a primary material for the synthesis of benzimidazole derivatives between various o-phenylenediamines ( 2a – l ) in the presence of Diisopropylethylamine (DIPEA) as a commercially available environmentally benign base, ethanol as a green solvent and the yield of all benzimidazole derivatives ( 3a – l ) was between 68–76 %; The semi-synthetically prepared benzimidazole derivatives ( 3a – l ) were assessed for their anti-bacterial and anti-fungal properties. The benzimidazole compounds ( 3a – b , and 3g – j ) exhibit good anti-microbial activity. In addition, in silico study was carried out to determine the specific binding affinity of the diamine halogen substituted benzimidazole derivatives to the specific target proteins. In silico analysis revealed a high correlation between docking results and experimental results. Finally, benzimidazole demonstrated significant antibacterial and antifungal activity. Zebrafish embryos were subjected to In vivo toxicological test found that all of the benzimidazole compounds ( 3a – l ) were non-toxic and had low embryotoxicity after 96 h, with an LC50 of 36.425 μg, which could facilitate the design of novel antimicrobial agents using a cost-effective method. 相似文献
112.
Protein synthesis in dormant embryos of sugar maple ( Acer saccharum ) was investigated in seeds stratified at 4°C or incubated at 15°C. Seeds stratified at 4°C germinated after 27 days; seeds incubated at 15°C failed to germinate. Stratification increased the embryo's capacity for protein synthesis by day 11 as measured by in vivo incorporation of [35 S]-methionine into purified protein. At 4°C protein synthesis in the embryonic axis rose in a linear fashion prior to germination, whereas in cotyledons it increased until day 20 and then declined. Analysis of radiolabelled proteins by two-dimensional gel electrophoresis revealed that the levels of specific proteins were altered by temperature, primarily in the cotyledons. Several proteins were expressed in the cotyledons at 15°C but were absent in unstratified embryos and in embryos stratified at 4°C. That is, the expression of these proteins was repressed during stratification and release from dormancy. Levels of other proteins in the cotyledons declined at 4°C during stratification. We suggest that one or more of these proteins may be associated with the inhibition of growth of the embryonic axis imposed by the cotyledons. 相似文献
113.
Atlantic salmon ( Salmo salar L.) fry hatched from eggs transferred from high-Na to low-Na water during the eyed stage of development had a significantly higher Vmax and lower Km (P <0.01) of the sodium uptake mechanism than fry hatched from eggs incubated entirely in low-Na or high-Na water.
Fry hatched from eggs transferred to acid, high aluminium water during the eyed stage of development had a similar Vmax and Km to fry hatched from eggs incubated entirely in high- or low-Na water. Eggs incubated continuously in acid, high aluminium (low-Na) water produced fry with significantly lower Km and Vmax values than fry hatched from eggs incubated continuously in low-Na water. Eggs and fry in acid, high aluminium water continually lost sodium and mortality was 100% at 5 5 M O degree-days (2–3 weeks after hatching).
The results are discussed with respect to the influence of perivitelline fluid ion activities in eggs in acid, high aluminium water on the kinetic characteristics of sodium uptake in yolk-sac fry. A possible mechanism for the long-term adaptation of teleosts in acidified natural waters is also proposed. 相似文献
Fry hatched from eggs transferred to acid, high aluminium water during the eyed stage of development had a similar V
The results are discussed with respect to the influence of perivitelline fluid ion activities in eggs in acid, high aluminium water on the kinetic characteristics of sodium uptake in yolk-sac fry. A possible mechanism for the long-term adaptation of teleosts in acidified natural waters is also proposed. 相似文献
114.
The kinetics of active sodium uptake in dechorionated embryos, yolk-sac fry and start-feed fry of Atlantic salmon were compared in two groups reared either in low conductivity, untreated, river water (conductivity ∼ 46 μS cm−1 , pH 5.75), or in 'improved' river water buffered with sea water (conductivity ∼2200 μS cm 1 , pH 6.56), the latter treatment often being used in commercial hatcheries to avoid problems associated with periodic acidification.
Maximal transport rate ( Vmax ) increased during development in both groups but was always significantly higher in embryos and fry maintained in untreated river water. Values for K m were not seen to vary during development up to 12 weeks after hatching and were not significantly different between groups, or from values reported for adult Atlantic salmon in fresh water.
The results are discussed with respect to the influence of Na+ concentrations in the perivitelline fluid of developing eggs and in the external medium surrounding fry on V max and K m . The ability of fry reared entirely in buffered river water to maintain sodium balance following transfer to untreated river water is also considered. 相似文献
Maximal transport rate ( V
The results are discussed with respect to the influence of Na
115.
Anna Filipek Agnieszka Zasada Urszula Wojda Robert Makuch Renata Dbrowska 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1996,113(4):745-752
Using a procedure developed to purify calcyclin from mouse Ehrlich ascites tumor cells calcyclin was purified from smooth muscle of chicken gizzard. Chicken gizzard calcyclin bound to phenyl-Sepharose in a calcium dependent manner as did mouse EAT cells and rabbit lung calcyclin but appeared to be more acidic than its mammalian counterparts as revealed by ion exchange chromatography on Mono Q. Chicken gizzard calcyclin bound 45Ca2+ on nitrocellulose filters and exhibited a shift in electrophoretic mobility on urea-PAGE depending on Ca2+ concentration. Crosslinking experiments with BS3 showed that chicken gizzard calcyclin was able to form noncovalent dimers. As indicated by a decrease in maximum tryptophan fluorescence emission of caldesmon (about 14% at 1:1 molar ratio) and displacement of calmodulin from its complex with caldesmon, chicken gizzard calcyclin binds caldesmon. This binding was, however, much weaker than that of calmodulin and could not influence the interaction of caldesmon with actin. In consequence, calcyclin was unable to reverse the inhibitory effect of caldesmon on actin-activated Mg2+-ATPase activity of myosin in the presence of Ca2+. 相似文献
116.
Brian K. Speake Ruth J. McCartney Marieke Feast André Maldjian Raymond C. Noble 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1996,115(4):493-499
Although substantial information is available regarding the fatty acid composition of lipids of the yolk and of the developing tissues of the chicken embryo, there is little knowledge on this topic for other avian species. The aim of the present study was to compare the yolk and embryonic tissue fatty acid profiles for a species selecting its food in the wild (the lesser black backed gull) with one fed on a standard commercial diet (the commercially reared pheasant). The fatty acid compositions of the yolk lipids were determined, and major differences were observed between the two species. In particular, the phospholipid of the gull yolk was enriched in 20:4n-6 and 22:6n-3 (18.8 and 7.1%, respectively, by weight of total fatty acids) in comparison with the pheasant (4.0 and 4.1%, respectively). The fatty acid compositions of the embryonic tissues were determined using eggs incubated in the laboratory. For the liver and heart, the fatty acid composition of the lipids in the two species reflected the initial yolk composition, with the gull tissue lipids generally containing higher proportions of 20:4n-6 and 22:6n-3 than those of the pheasant. In contrast, the fatty acid profiles of the brain phospholipid were essentially identical in the two species, with 20:4n-6 and 22:6n-3 comprising approximately 9 and 17%, respectively, of total fatty acids in both cases. 相似文献
117.
118.
The gibberellin (GA)-biosynthesis mutations, lh
i
, ls and Ie
5839
have been used to investigate the role(s) of the GAs in seed development of the garden pea (Pisum sativum L.). Seeds homozygous for lh
i
possess reduced GA levels, are more likely to abort during development, and weigh less at harvest, compared with wild-type seeds due to expression of the lh
i
mutation in the embryo and/ or endosperm. Compared with wild-type seeds, the lh
i
mutation reduces endogenous GA1 and gibberellic acid (GA3) levels in the embryo/endosperm a few days after anthesis and fertilizing lh
i
plants with wild-type pollen dramatically increases GA1 and GA3 levels in the embryo/ endosperm and restores normal seed development. By contrast, the ls and le
5839
mutations do not appear to reduce GA levels in the embryo/endosperm of seeds a few days after anthesis, and do not affect embryo or endosperm development. However, both the ls and lh
i
mutations substantially reduce endogenous GA levels in embryos at contact point (the first day the liquid endosperm disappears). Levels of GAs in seeds from crosses involving the ls and lh
i
mutations suggest that GAs are synthesised in both the embryo/endosperm and testa and that the expression of ls depends on the tissue and developmental stage examined. These results suggest that GAs (possibly GA1 and/or GA3) play an important role early in pea seed development by regulating the development of the embryo and/or endosperm. By contrast, the high GA levels found in wild-type seeds at contact point (and beyond) do not appear to have a physiological role in seed development.Abbreviations GAn
gibberellin An
- DAA
days after anthesis
- WT
wild-type
We thank Noel Davies, Katherine McPherson and Peter Bobbi for technical assistance, Professor L. Mander (ANU, Canberra) for dideuterated GA standards, and the Australian Research Council and Frontier Research Program, The Institute of Physical and Chemical Research (RIKEN, Japan), for financial support. 相似文献
119.
Branka Kolevska-Pletikapić Zinka Buturović-Derić 《Plant Cell, Tissue and Organ Culture》1995,41(2):189-192
Picea omorika plants were regenerated from embryo and seedling shoot tip cultures. Adventitious and axillary shoots were produced on 1/2 MS medium containing benzyladenine and kinetin. Benzyladenine was more effective in bud induction, whereas kinetin hastened shoot development. Excised shoots were elongated on 1/3 MS medium without growth regulators, multiplied with kinetin and rooted with or without indole-3-butyric acid.Abbreviations BA
N6-benzyladenine
- 2IP
N
6-(2-isopenteny) adenine
- NAA
-naphthaleneacetic acid
- IAA
indole-3-acetic acid
- IBA
indole-3-butyric acid 相似文献
120.
The efficiency of guanidine hydrochloride (GuHCl) addition in the suppression of gel formation and the extraction of lysozyme during reverse micellar extraction from chicken egg white was investigated. A low concentration of GuHCl in the feed permitted the successful extraction of lysozyme in its native form without gel formation, which is perceived as a novel function of GuHCl. The highest recovery and specific activity of lysozyme were obtained at a GuHCl concentration of 0.06 M in 25 mM AOT reverse micellar extraction from 20-fold-diluted natural chicken egg white. Lysozyme and ovalbumin CD spectra in the corresponding GuHCl aqueous solutions revealed no changes in the higher order structures of the proteins. Furthermore, the specific activity of lysozyme in the feed was well preserved in the GuHCl system. (c) 1995 John Wiley & Sons, Inc. 相似文献