茄科蔬菜花青素苷分子调控研究进展

花青素苷是一种分布广泛的水溶性色素,不仅赋予了果实多彩的外表,还是天然食用色素的重要来源。近年来有关茄科蔬菜花青素苷的研究逐渐增多,文中从花青素苷结构及其生物合成途径、茄科蔬菜中花青素苷合成代谢的结构基因和调节基因、影响合成的环境因素等方面进行回顾和总结,为进一步阐明茄科蔬菜花青素苷的合成及调控机理、更好利用花青素苷进行果色品质育种的创新提供一些参考。     

Light induced changes in anthocyanin concentration,activity of phenylalanine ammonia-lyase and flavanone synthase and some of their properties in Brassica oleracea

Seedlings of red cabbage, Brassica oleracea cv Red Danish, germinated in the dark, rapidly produced anthocyanins upon illumination. The anthocyanin production increased up to six days of illumination time. The activity of phenylalanine ammonia-lyase increased rapidly in illuminated seedlings to a maximum at 8 hr and declined thereafter to dark levels. During this period the activity of flavanone synthase, the first enzyme responsible for the establishment of C₁₅ flavonoid skeleton, paralleled that of the anthocyanin concentration. The crude flavanone synthase has a pH optimum at around 8, a molecular weight of ca 120 000, and is able to utilize only p-coumaryl-CoA as co-substrate for the production of flavonoids.     

The allelic state at intensifier influences the accumulation of UDP glucose: Flavonoid 3-O-glucosyltransferase in maize

In a variety of genetic backgrounds in maize (Zea mays), homozygosity for the recessive allele intensifier (in) conditions strikingly deepe     

Photomorphogenic responses to UV radiation IV: a comparative study of UVB effects on growth and pigment accumulation in etiolated and de-etiolated hypocotyls of wild-type and aurea mutant of tomato Lycopersicon esculentum Mill)

ABSTRACT

The question of how de-etiolation of tomato seedling under continuous monochromatic yellow light exerts an influence on UV radiation-induced responses has been studied. Hypocotyl extension and the accumulation of anthocyanins and UV-absorbing compounds was compared in the aurea mutant of tomato and its isogenic wild type. The data of the present paper provide evidence that, during de-etiolation of tomato seedlings, yellow light exerts its effects over seedlings responsiveness to subsequent UV irradiation through several mechanisms: 1) a significant enhancement of shorter UVB wavelength efficiency in both the genotypes; 2) the abolition of UVA -blue light-induced accumulation of UV-absorbing compounds that does not involve pnyA; 3) the disappearance of UVA-blue light-induced hypocotyl growth inhibition that does not involve phyA; 4) higher anthocyanin accumulation rate in response to UV radiation mediated by phyA. Yellow light-induced growth inhibition and accumulation of UV-absorbing compound both mediated by phyA and present only in wild type tomato, appear to be completely separate from the action of UV radiation on the same responses.     

香樟果皮花色苷提取工艺优化及抗氧化研究

为了优化香樟果皮花色苷的最佳提取工艺条件,用乙醇作为提取溶剂,选取提取时间、提取温度、提取剂浓度、料液比、pH五因素,采用Box-Behnken建立三因素三水平模型,用响应面法优化各因素及其相互作用的最佳组合,用Design-Expert 8.0设计回归正交实验;同时用水杨酸比色法和DPPH法,测定了香樟果皮花色苷的抗氧化能力,并比较了不同放置时间对香樟果花色苷稳定性的影响。结果表明:香樟果花色苷最佳提取工艺的回归方程为Y=58.64+2.27A+12.78B+10.18C-14.01A2-11.00B2-7.56C2,R2=0.9796,模型拟合程度良好,在该试验范围内,模型能够准确反映花色苷的提取结果;最佳工艺参数分别为pH1.0、料液比1∶15、乙醇浓度78.59%、提取温度77.14℃、提取时间42.48min,在此条件下香樟果花色苷的得率为67.99mg·100g-1;在一定浓度范围内,香樟果皮花色苷清除羟自由基率和总抗氧化能力均与浓度成正线性相关,回归方程分别为y=0.3388x+13.485(R2=0.9856),y=0.0275x+0.0221,(R2=0.9966)。利用响应面法确定的最佳工艺条件合理,可用于香樟果皮花色苷的提取,同时香樟果花色苷具有良好的抗氧化活性,为天然色素的开发利用提供一定指导意义。     

Variation in anthocyanin and essential oil composition and their antioxidant potentialities during flower development of Borage (Borago officinalis L.)

The aim of this study was to examine the chemical composition and antioxidant activities of the essential oils and anthocyanin of Borago officinalis flowers. At the flowering stage, the essential oil yield in Korba (0.95 ± 0.03%) was higher than that in Beja (0.29 ± 0.03%, w/w). The essential oil composition was characterized by high proportions of (E,E)-decadienal, the main compound of monoterpene aldehydes class. The reverse phase–high-performance liquid chromatography–mass spectrometry analysis indicated that flower anthocyanins were extracted and analysed for the first time and petunidin 3,5 diglucoside (58.8% in Korba and 54.93% in Beja) was the major anthocyanin followed by delphinidin 3,5 diglucoside (36.45% in Korba and 44.45% in Beja). During the development of borage flower, anthocyanin yield increased significantly (P < 0.05) from budding to full flowering stages in the two studied regions. Antioxidant activity of anthocyanin extracts and essential oil followed the same trend as anthocyanin and essential oil yields in Korba and Beja regions. In all tests, anthocyanin extracts of borage flowers showed better antioxidant activity than essential oils. A notable variability was found among the anthocyanin and essential oil concentrations and their antioxidant activities between the two studied regions, indicating a strong influence of the degree of maturity on metabolite production.     

Comparative Metabolomics Analysis between Red- and White-Flowered Common Buckwheat Cultivars

Common buckwheat (Fagopyrum esculentum), a specialty crop in southwest China, is not only used as a supplement to primary grain crops but also to produce beverages, such as tea and wine. To fully exploit the products made from common buckwheat flower, ultra-performance liquid chromatography–electrospray ionization– tandem mass spectrometry (UPLC–ESI–MS/MS) was conducted to analyze the metabolites in red- (‘Guihong 2’) and white-flowered (‘Fengtian 1’) buckwheat cultivars. A total of 784 metabolites were identified of which flavonoids were the largest group with 191 components, followed by organic acids and derivatives (126), and amino acids and derivatives (95). Besides, dozens of phenylpropanoids, nucleotides and derivates, lipids, alkaloids as well as several kinds of indole derivatives and sterides were detected. Among these rich varieties of metabolites, 24 metabolites were only detected in the red flower that mainly included 8 anthocyanins and 6 flavones, while 22 metabolites were only detected in the white flower, which mainly contained 5 lipids, 5 flavonoids, and 5 organic acids and derivatives. Our results enrich the metabolites’ information of buckwheat and may be helpful for the exploitation of products from common buckwheat flowers.