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51.
高胡萝卜素甘薯亲本材料的引进、筛选、创新与应用   总被引:1,自引:0,他引:1  
通过广泛引进鉴定甘薯品种资源,筛选出胡萝卜素含量高、开花习性好的高胡萝卜素甘薯亲本徐22-5、96-58-2等.并对性状遗传特性进行了测定,明确了胡萝卜素的遗传为加性效应,F1代与亲本存在着极显著的正相关,相关系数r=0.941 6**,据此提出高胡萝卜素甘薯亲本筛选的基本原则.  相似文献   
52.
环境条件对光合细菌B.9菌株产生类胡萝卜素的影响   总被引:5,自引:2,他引:3  
本文讨论了光照、通气、培养温度、培养时间对沼泽红假红假单胞菌B.9菌株类胡萝卜素组成、相对含量、存在状态的不同程度的影响,探讨类胡萝卜素合成的调控机制。  相似文献   
53.
对植物中胡萝卜素的分析作了较为全面的研究,虽然该组分的柱层析—分光光度法早已建立,但很少有人去认真探讨影响方法效能的诸因素,造成不同作者之操作条件差异很大。为此我们在现代色谱理论指导下,从提高柱效出发,对操作条件和柱型加以讨论和改进。用20×0.8(ID)cm柱管,填60~100目层析用氧化铝,以及从多方面保证进样过程快速和成“塞状”。结果使方法的重复性、回收率及检测低含量样品的能力都大为提高,在样品含量为0.01%~0.1%时,相对标准偏差降低至2.5%,回收率达97~99%。新设计的层析装置使操作及设备变得更简便。并给出了不同形态样品的前处理方法。  相似文献   
54.
仟禾福水溶肥对烤烟质体色素及其降解产物的影响   总被引:2,自引:0,他引:2  
为了研究仟禾福水溶肥在烤烟生产中的应用,以烤烟品种龙江911为材料,研究了仟禾福水溶肥不同稀释倍数和喷施方式对烤烟质体色素及其降解产物的影响。结果表明:仟禾福水溶肥以800倍稀释,于团棵期+旺长前期+旺长后期各喷施1次处理的烤烟质体色素含量及其降解产物含量最多,分别为215.81、535.85μg/g,烟叶品质较好。与喷施清水的对照相比,其叶绿素含量、类胡萝卜素含量、新植二烯、类胡萝卜素降解产物总量分别增加28.0%、54.7%、26.4%、57.3%。  相似文献   
55.
Pasture fed cattle ingest substantial amounts of βcarotene (β‐C). Not all of the carotenoid compound is transformed into vitamin A, but the surplus is deposited in adipose tissue (AT). The mechanisms of β‐C incorporation and mobilization are unknown. Two experiments were conducted using explants from bovine AT cultured in vitro. First, β‐C incorporation by explants from three animals was examined with different β‐C concentrations (0, 1, 5 and 20 μm ) and different times of incubation (every 5 h up to 25 h). The data showed a significant increase of β‐C concentration in explants only for 20 μm β‐C. Secondly, effects of insulin and epinephrine on β‐C and triglyceride (TG) contents of explants were studied. Explants from six animals were incubated with either hormone and 0 or 20 μm β‐C for 20 h. Both TG and β‐C contents were affected positively by insulin and negatively by epinephrine. Interestingly, changes in ratios of β‐C/TG (hormone vs. control) were similar (1.7 × 10?3 and 1.8 × 10?3), respectively, for insulin and epinephrine, indicating that β‐C level is directly related to TG content. We also report the presence of mRNA for β‐C 15, 15′ oxygenase in bovine AT. The in vitro culture system using explants from bovine AT is a promising model to investigate factors that might affect the accumulation and metabolism of β‐C.  相似文献   
56.
Twenty vegetable amaranth genotypes were evaluated for total antioxidant capacity, antioxidant leaf pigments, vitamins, and selection of suitable genotypes for extraction of juice in a randomized complete block design(RCBD) with three replications. Vegetable amaranth was rich in chlorophyll, β-cyanins, β-xanthins, betalains, carotene, ascorbic acid and total antioxidant. The genotypes VA14, VA16, VA18, VA15, and VA20 could be selected as amaranth vegtable varieties with high yields and abundance antioxidant leaf pigments and vitamins to produce juice. The genotypes VA13 and VA19 had above-average foliage yield and high antioxidant profiles while the genotypes VA2, VA3, VA9, VA11, VA12, and VA17 had a high antioxidant profiles and below-average foliage yield. These genotypes could be used as a donor parent for integration of potential high antioxidant profiles genes into other genotypes. The correlation study revealed a strong positive association among all the antioxidant leaf pigments, total antioxidant capacity and foliage yield. Selection based on total antioxidant capacity, antioxidant leaf pigments could economically viable to improve the yield potential of vegetable amaranth genotypes. Total carotene and ascorbic acid exhibited insignificant genotypic correlation with all the traits except total antioxidant capacity. This indicates that selection for antioxidant vitamins might be possible without compromising yield loss.  相似文献   
57.
Seedlings of rice, early watergrass (thiobencarb-resistant and thiobencarb-susceptible biotypes, R and S, respectively), and late watergrass (thiobencarb-resistant and thiobencarb-susceptible biotypes, R and S, respectively) were hydroponically exposed to clomazone at concentrations ranging from 0.08 to 7.9 microM. Whole-plant growth (mg fresh wt) and beta-carotene concentrations (microg g(-1) fresh wt) were measured after a 7-day exposure period. For growth, the no observed effect concentrations (NOECs) were 7.9, 0.21, 0.21, 0.46 and 0.46 microM clomazone for rice, early watergrass (R), early watergrass (S), late watergrass (R) and late watergrass (S), respectively, while the concentrations causing 25% inhibition in response (IC25) were 5.6 (+/-1.6), 0.46 (+/-0.06), 0.42 (+/-0.08), 0.92 (+/-0.45) and 0.79 (+/-0.08) microM clomazone, respectively. Clomazone inhibits beta-carotene synthesis via inhibition of the non-mevalonate isoprenoid synthetic pathway. For assessment of clomazone effects, beta-carotene levels proved to be a more sensitive toxicological endpoint than growth. For rice, early watergrass (R), early watergrass (S), late watergrass (R) and late watergrass (S), the beta-carotene NOECs were 0.21, <0.08, <0.08, 0.08 and 0.46 microM clomazone respectively, while IC25 values were 0.42 (+/-0.26), 0.08 (+/-0.02), 0.08 (+/-0.02), 0.33 (+/-0.09) and 0.54 (+/-0.15) microM, respectively. No evidence was found that the thiobencarb-resistance mechanisms present in early and late watergrasses impart resistance to clomazone. Due to similar sensitivity between rice and late watergrass, use of clomazone in rice culture will require the use of a safening technique.  相似文献   
58.
The new bleaching herbicidal compound N,N‐diethyl‐N‐(2‐undecynyl)amine (NDUA) is identified here as an inhibitor of lycopene cyclase and is compared with the known cyclase inhibitors N,N‐diethyl‐N‐[2‐(4‐chlorophenylthio)ethyl]amine (CPTA) and N,N‐diethyl‐N‐[2‐(4‐methylphenoxy)ethyl]amine (MTPA). HPLC separation of chloroplast pigments shows lycopene accumulation in NDUA treated tissue. Variation in chain length of the undecynylamine moeity of NDUA from 7 to 21 C atoms reveals an optimum of 11 to 14 C atoms for herbicidal activity. A series of seven further analogues of NDUA and CPTA reveals the structural elements necessary for inhibition of lycopene cyclase. The effect of NDUA derivatives on photosynthesis has been studied in Chlamydomonas reinhardtii. Photosynthesis is highly sensitive, particularly towards the C14 and longer chain length analogues at nanomolar concentrations. It is shown that the breakdown of photosynthesis by NDUA is due to interference with the turnover of the D1 protein of the photosystem II reaction centre that requires the continous biosynthesis of the two reaction‐centre β‐carotene moieties in the reassembly phase. The D1 protein disappearance is most marked under strong light conditions. The depletion of photosystem II occurs before total pigment bleaching. This newly recognized mechanism in herbicidal activity is also the basis for the mode of action of other lycopene cyclase inhibitors as well as phytoene desaturase inhibitors. © 2001 Society of Chemical Industry  相似文献   
59.
Data from 19 Japanese Black multiparous cows were collected to clarify the relationships among immunoglobulin (Ig) G, IgA, β‐carotene, vitamin A and α‐tocopherol contents in colostrum of cows in order to evaluate the role of fat‐soluble vitamins on colostral IgG and IgA production. Mean colostral IgG was 141 mg/mL, ranging from 65 to 208 mg/mL, whereas mean colostral IgA was 8.7 mg/mL, ranging from 1.0 to 34.6 mg/mL. Colostral IgG increased with aging in multiparous cows. There were positive correlations between colostral IgG and colostral vitamin A or colostral α‐tocopherol in cows, and the higher adjusted R2 was obtained in the prediction model of colostral IgG from age and colostral vitamin A. Colostral vitamin A was positively correlated with colostral β‐carotene or colostral α‐tocopherol in cows, but there were no relationships between colostral IgA and colostral IgG or colostral fat‐soluble vitamins. These results indicate that fat‐soluble vitamin contents in colostrum of cows may change in similar patterns and high colostral vitamin A is related with high colostral IgG.  相似文献   
60.
This study was performed to evaluate the effect of dietary natural carotenoid sources on skin colour enhancement of false clownfish Amphiprion ocellaris. The juvenile fish (initial body wt. 0.30 g) were fed with four experimental diets including (a) commercial feed (reference diet), (b) moist feed, (c) sweet potato (potato diet) and (d) dried gut weed Enteromorpha sp. (gut weed diet). Sweet potato and gut weed were used to boost up β‐carotene levels in the diets. There was no significant difference in final weight (0.51 ± 0.02 – 0.61 ± 0.01 g) and length (2.80 ± 0.02 cm) of fishes among treatments (p > 0.05) after 8 weeks. The survival rate of the fish in all dietary treatment was greater than 89%. Principal component analysis results showed that fish fed potato and gut weed diets performed brighter colour in skin with more orangeness, body and accumulated β‐carotene levels were higher than those fish fed with reference diet. Indicator a* value for the redness of fish fed potato diet (16.18 ± 0.59) and gut weed (14.36 ± 2.14) was also higher than fish fed reference diet (10.92 ± 0.82). The result of this study provided key information for developing dietary colour enhancement of ornamental fish by using cost‐effective feed ingredients (potato and gut weed) as natural supplemental carotenoid sources.  相似文献   
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