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61.
Rate of photosynthesis and activities of photosynthetic carbon reduction cycle enzymes were determined in pods (siliqua),
whereas rate of dark CO2 fixation, oil content and activities of enzymes involved in dark CO2 metabolism were measured in seeds ofBrassica campestris L. cv. Toria at different stages of pod/seed development. The period between 14 and 35 days after anthesis corresponded to
active phase of seed development during which period, seed dry weight and oil content increased sharply. Rate of pod photosynthesis
and activities of photosynthetic carbon reduction cycle enzymes were maximum in younger pods but sufficiently high levels
were retained up to 40 days after anthesis. The rate of dark14CO2 fixation in seeds increased up to 21 days after anthesis and declined thereafter but maintaining sufficiently high rates
till 35 days after anthesis. Similarly various enzymes viz., phosphoenolpyruvate carboxylase, NAD+-malate dehydrogenase and NADP+-malic enzyme, involved in dark CO2 metabolism retained sufficient activities during the above period. These enzyme activities were more than adequate to maintain
the desired supply of malate which mainly arises from dark CO2 fixation in seeds and further translocated to leucoplasts for onward synthesis of fatty acids. Enzyme localization experiments
revealed phosphoenolpyruvate carboxylase and enzymes of sucrose metabolism to be present only in cytosol, whereas enzymes
of glycolysis were present both in cytosolic and leucoplastic fractions. These results indicated that oil synthesis in developingBrassica seeds is supported by pod photosynthesis and dark CO2 fixation in seeds as the former serves as the source of sucrose and the latter as a source of malate 相似文献
62.
Karuna Shanker Seema Mishra Shalini Srivastava Rohit Srivastava Sahab Daas Satya Prakash M. M. Srivastava 《Plant and Soil》1996,183(2):233-238
Pot culture experiments containing sand and soil, at two levels of mercury (2 and 5 g mL-1) added through irrigation with increasing supplementation of selenium (selenite and selenate) led to a decrease in the uptake of mercury by tomato (Lycopersicum esculentum) plant. Both the forms of selenium (selenite and selenate) were found to be equally effective in reducing the mercury accumulation by plants. The observed reduction pattern of mercury accumulation in plant tissues has been discussed on the basis of the formation of insoluble HgSe complex in soil-root environment. 相似文献
63.
A re-investigation of the root bark of Tabernaemontana divaricata resulted in the isolation of 18 compounds, viz. α-amyrin acetate, lupeol acetate, α-amyrin, lupeol, cycloartenol, β-sitosterol, campesterol, benzoic acid, aurantiamide acetate, coronaridine, coronaridine hydroxyindolenine (1), ibogamine, 5-hydroxy-6-oxocoronaridine (6), 5-oxocoronaridine (9), 6-oxocoronaridine (10), (±)-19-hydroxycoronaridine (11), 3-oxocoronaridine (12) and voacamine. The alkaloids 6, 9, 10 and 11 are new compounds, whereas cycloartenol, campesterol, ibogamine, benzoic acid, aurantiamide acetate and coronaridine hydroxyindolenine are reported from this plant for the first time. 相似文献
64.
Two new pentacyclic triterpenoids characterized as 16α-hydroxy-3-ketoisomultiflorene and 3β-hydroxy-16-ketoisomultiflorene have been isolated from the aerial parts of Antidesma menasu. Both of these compounds displayed diuretic activity in experimental animals. 相似文献
65.
1-Ricinoleoyl-2-acyl-sn-glycero-3-phosphocholine was prepared by incorporating ricinoleic acid completely in the sn-1 position of egg and soya phosphatidylcholine (PC) using immobilized phospholipase A(1) as the catalyst. The optimum reaction conditions for maximum incorporation of ricinoleic acid into PC through transesterification were 10% (w/w) immobilized enzyme (116 mg), a 1:5 mol ratio of PC (soya, 387 mg; egg, 384 mg) to methyl ricinoleate (780 mg) at 50 degrees C for 24 h in hexane. 相似文献
66.
Isolation and characterization of cytosolic alanine aminotransferase isoforms from starved rat liver
Maulik N 《Molecular and cellular biochemistry》2004,264(1-2):13-23
Despite significant advances in myocardial revascularization and reperfusion, coronary artery disease and subsequently myocardial infarction, are the leading causes of morbidity and mortality in the United States. Strategies which improve the myocardial substrate during and following a myocardial infarction-such as the regrowth of functional blood vessels to the ischemic myocardium would be of great clinical importance. This review article attempts to address this important clinical issue through identifying potential signalling mechanisms by various mode of preconditioning that cause angiogenesis. 相似文献
67.
Vijai Lakshmi Dhan Prakash Kanwal Raj Randhir S. Kapil Satya P. Popli 《Phytochemistry》1984,23(11):2629-2631
A reinvestigation of Clausena anisata has yielded imperatorin, xanthotoxol, lansamide-I and three new furanocoumarin lactone derivatives: indicolactone, anisolactone and 2′,3′-epoxyanisolactone. The structures of these compounds have been elucidated by a combination of spectroscopic and chemical methods. 相似文献
68.
Maternal nutrition, especially LCPUFA, is an important factor in determining fetal growth and development. Our earlier cross sectional study reports lower docosahexanoic acid (DHA) levels at the time of delivery in mothers delivering low birth weight (LBW) babies. This study was undertaken to examine the role of the maternal omega-3 and omega-6 fatty acid profile across the gestation in fetal growth. This is a hospital based study where women were recruited in early gestation. Maternal blood was collected at 3 time points, i.e., T1 = 16th–20th week, T2 = 26th–30th week and T3 = at delivery. Cord blood was collected at delivery. At delivery, these women were divided into 2 groups: those delivering at term a baby weighing >2.5kg [Normal birth weight (NBW) group] and those delivering at term a baby weighing <2.5kg [LBW group]. The study reports data on 111 women recruited at T1, out of which 60 women delivered an NBW baby at term and 51 women delivered an LBW baby at term. Fatty acids were analysed using gas chromatography. At T1 of gestation, maternal erythrocyte DHA levels were positively (p<0.05) associated with baby weight. Maternal plasma and erythrocyte arachidonic acid and total erythrocyte omega-6 fatty acid levels at T2 were higher (p<0.05 for both) in the LBW group. Total erythrocyte omega-3 fatty acid levels were lower (p<0.05) while total erythrocyte omega-6 fatty acid levels were higher (p<0.05) in the LBW group at delivery. Our data demonstrates the possible role of LCPUFA in the etiology of LBW babies right from early pregnancy. 相似文献
69.
70.