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The effect of hormone-like compounds at different concentrations: 2,4-D (2 × 10?6; 2 × 10?5; and 2 × 10?4M) and 1-NAA (2 × 10?7; 2 × 10?6; 2 × 10?5; 4 × 10?5, and 6 × 10?5 M) on the growth and production of phenolic compounds, including flavans and lignin, was investigated in callus culture of tea plant (Camellia sinensis L., a highly productive strain IFR ChS-2). The growth of the culture was vigorous, and production of phenolic compounds therein was efficient in the medium containing 2 × 10?5 M 2,4-D. Substitution of 1-NAA for 2,4-D in all the cases decelerated the growth of the culture. These changes were more pronounced when 2 × 10?7 and 2 × 10?6 M 1-NAA was used; in this case, biomass accumulation decreased by 1.5–2.0 times as compared with control material growing on the medium with 2 × 10?5 M 2,4-D. In the presence of 1-NAA, the content of total soluble phenolic compounds and flavans in the calli rose by 30% on the average as compared with control material. Accumulation of lignin remained essentially the same. Therefore, the replacement of 2,4-D with 1-NAA in the nutrient medium used for the growing of highly productive strain of tea plant callus did not induce considerable changes in its ability to produce phenolic compounds.  相似文献   
2.
Flavans and procyanidins from the seeds of different grape varieties were separated and identified using HPLC techniques. The compounds identified were (+)-catechin and (?)-epicatechin, dimeric procyanidins B1, B2, B3 and B4, trimeric procyanidin C2 and gallic acid. During maturation of the grape berries, the flavan-3-ol content fell in the seeds whereas procyanidin levels increased. This suggests an interrelationship between the compounds. There was also evidence of varietal differences in the amounts of phenolic compounds in grape seeds.  相似文献   
3.
Trunk wood of Iryanthera laevis Markgr. (Myristicaceae) contains 2′,4′-dihydroxy- 4,6′dimethoxydihydrochalcone, three 2′-hydroxy-4′,5′-methylenedioxyflavans with differently substituted A-rings (7-OH-6,8-diMe; 7-OH-5,8-diMe; 5-OH-7-OMe-6,8-diMe) and 1-(2′-hydroxy-4′-methoxy-5′-methylphenyl)-3(2″-hydroxy-4″,5″-methylenedioxphenyl)- propane, as well as three additional known diarylpropanes.  相似文献   
4.
From the roots of Hoppea dichotoma, collected before flowering, two new naturally occurring glucosyloxyflavans, dichotosin and dichotosinin, have been isolated and characterized by means of comprehensive spectral analyses, chemical transformation and synthesis of the aglucone of dichotosin. This is the first report of dichotosinin from a natural source. Additionally, one known glucosyloxyflavan, diffutin, earlier reported in another Gentianaceae species (Canscora diffusa) also has now been isolated from this species. The glucosyloxyflavans, individually and in combination, produced varying degrees of adaptogenic (anti-stress-anti-anxiety) activity in animal models. This observation is consistent with the use of the plant extract as a nerve tonic in Ayurvedic medicine.  相似文献   
5.
The effects of cadmium (6.3 × 10?5 M or 10.6 × 10?5 M) on the growth of tea plant (Camellia sinensis L.) callus cultures derived from leaves, stems, and roots and on the formation, in these cultures, of phenolic compounds, including flavans and lignin, which are characteristic of the tea plant, were investigated. In the calli derived from leaves and stems, cadmium treatment decreased the biomass increment, while in the calli derived from roots, growth characteristics remained at the control level. Under the effect of cadmium, the content of phenolic compounds, including flavans, in the leaf calli decreased, while in the stem and root calli, it either increased (at the cadmium concentration of 6.3 × 10?5 M), or was close to a control one (at the cadmium concentration of 10.6 × 10?5 M). The lignin content in the root and stem calli increased, but it did not change in the leaf calli. All this data demonstrate that the cadmium-induced changes in phenolic metabolism of the tea plant callus culture depended both on the cadmium concentration in the medium and on the origin of calli.  相似文献   
6.
The naturally occurring free and glycosylated flavans are reviewed. The distribution, methods of isolation and structure elucidation of flavans, by comprehensive spectral analyses, are presented. Biological properties of flavans are appraised.  相似文献   
7.
黄花石蒜中的黄酮类成分   总被引:3,自引:0,他引:3  
通过对黄花石蒜(Lycoris aurea)乙醇提取物的乙酸乙酯溶解部分进行分离纯化,得到7个化合物.经物理方法和波谱分析,分别鉴定为(2S)-4'-羟基-7-甲氧基黄烷(1)、(2S)-3',7-二羟基-4'-甲氧基黄烷(2)、(2S)-4',7-二羟基黄烷(3)、(2S)-4',7-二羟基-8-甲基黄烷(4)、(2S)-4',7-二羟基-3'-甲氧基-8-甲基黄烷(5)、(2S)-4',5,7-三羟基-8-甲基黄烷酮(6)、2,4'-二羟基-4-甲氧基二氢查尔酮(7).所有化合物均为首次从该属植物中分离得到,另外,本文首次归属了化合物5、6、7的13C NMR信号.  相似文献   
8.
Sephadex LH-20 chromatography was used to fractionate purified ethyl acetate-soluble thearubigins, prepared from an aqueous ethanolic extract of black tea. Three subfractions were so produced, each having a MW of about 1500 and each being degradable into cyanidin, delphinidin, gallic acid, the same two flavan-3-ols, and the same two flavan-3-ol gallates, though in different yield. Some evidence for the presence of benzotropolone moieties in at least one of the subfractions was obtained. Overall the ethyl acetate-soluble thearubigins are viewed as pentameric flavan-3-ols/flavan-3-ol gallates, containing both hydrolysable and non-hydrolysable interflavanoid links, as well as benzotropolone units, rather than as polymeric proanthocyanidins, a term previously used for all thearubigin subgroups.  相似文献   
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