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1.
The essential oils of Pinus sylvestris from French Massif Central are described. Forty-six compounds have been identified by spectral methods. Two chemotypes are recognized.  相似文献   

2.
The dominant gene Lm that causes 60–90% limonene/cineole was substituted into M. aquatica by four convergent backcrosses. The natural strain of M. aquatica has 7·7% cineole, 4·9% limonene, traces of terpinolene and pulegone, 0·1% menthone, 0.2% menthol, and 66·4% menthofuran. The two modified hybrid strains with dominant gene Lm have 53·8 and 78·7% limonene/cineole and a total of only 1·0-3·8% 3-oxygenated compounds in contrast to a total of 66·7% found in the natural strain. The postulate is made that the Lm gene largely prevents either the conversion of a-terpineol → terpinolene or of limonene → isopiperitenone and that in these strains the recessive cc genotype largely but not completely prevents the conversion of limonene → carvone resulting in limonene accumulation. Mentha species almost invariably have either 2-oxygenated or 3-oxygenated compounds, not both. Close coupling phase linkage of the genes Lm and C explains why the self-pollinated progeny of M. spicata or M. crispa C-Lm/c-lm have a ratio of 3 carvone/dihydrocarvone: 1 pulegone/menthone rather than a ratio of 9 carvone : 3 limonene : 3 carvone and menthone: 1 menthone which would be expected if the genes Lm and C were independently inherited  相似文献   

3.
The monoterpenes of the fruits of Pittosporum resiniferum and P. undulatum have been identified. The essential oil of P. resiniferum contai  相似文献   

4.
R.W. Scora 《Phytochemistry》1973,12(1):153-155
Green, variegated and albino leaves of Myrtus communis yield mono- and sesqui-terpenes which show considerable variation in their ratios when compa  相似文献   

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The essential oil content of Hungarian samples of Tanacetum vulgare varies from 0.02 to 0.66% and exhibits a heterogeneous distribution indicating genetic variation. The rotatory power of the essential oil is also widely divergent and plants containing laevo-rotatory essential oils mainly occur in large numbers in the region east of the Tisza. The essential oil composition of wild plants remained constant during their cultivation. 26 different chemoforms have been found so far in Hungary. Individuals and populations containing artemisia ketone and umbellulone as their main components are the most frequent.  相似文献   

7.
The diversity of essential oils of Thymus vulgaris L., native in France, arises from the existence of 6 chemotypes (geraniol, linalol, α-terpineol, thujanol-4 and terpineol-4, thymol and carvacrol), whose specific characters are stable both in natural habitats and in experimental culture, and are hereditically transmissible. Genetic and ecological factors, specially climatic, determine the distribution frequency of the chemotypes among populations. These ‘chemical varieties’ are considered to be infraspecific, the species being homogeneous from morphological and karyological criteria.  相似文献   

8.
Three amylases E1, E2 and E3 have been extracted from Passe-Crassane pears pulp and partially purified. A good extraction of these enzymes is obtained only with non ionic detergents. Furthermore, solubilization of amylase E1 needs the use of these compounds. Separation of the 3 amylases is obtained by chromatography on Sephadex G100. E1 and E2 are β-amylases whereas E3 is an α-amylase. The first two have similar kinetic properties and interconversion of one form into the other is possible. It is suggested that the insoluble form E1 is the result of the association of β-amylase E2 with other compounds present in the fruit.  相似文献   

9.
The microbial transformations of (−)-α- and (+)-β-thujone (1a and 1b) in cultures of Absidia species: Absidia coerulea AM93, Absidia glauca AM254 and Absidia cylindrospora AM336 were studied. The biotransformations of (−)-α-thujone (1a), by these fungi strains, afforded mixtures of 4-hydroxy- and 7-hydroxy-α-thujone (2 and 3). Aforementioned fungi strains were also able to hydroxylate of (+)-β-thujone at C-7 position. Only A. glauca AM254 transformed 1b to 8-hydroxy-β-thujone (7) and (2S)-2-hydroxyneoisothujol (6). The (4R)-4-hydroxyisothujole (5) was identified as one of the major metabolite of (+)-β-thujone (1b) in culture of A. cylindrospora AM336. This strain was also able to introduce hydroxy group to C-4 position in 1b without reduction of carbonyl group at C-3. The absolute configuration of all chiral centers of new (4R)-4-hydroxyisothujol (5) and (2S)-2-hydroxyneoisothujol (6) were established taking into account the configuration of (+)-β-thujone (1b) and their spectral data.  相似文献   

10.
    
A sample of the lichen Asahinea chrysantha collected in the northern region of the Soviet Far East contained α- and β-alectoronic acids, while the same lichen collected in the southern region contained the methoxy derivatives, α- and β-collatolic acids, of these two acids.  相似文献   

11.
Callus cultures of Pinus radiata that synthesized monoterpenes de novo and which were stable for at least 1 year have been established. The products differed from those of parent plants in that α-pinene (87–100%) rather than β-pinene was the main component. The best lines accumulated monoterpenes (ca 2 × 10?3% wt/wet wt)in yields 40–20% of that in the parent stem and needles. The composition of the extractable oil depended on the light regime. After culture in total darkness toluene and acetone accumulated. These compounds also occurred (at low levels) in dark-grown seedlings and in seeds of P. radiata and a route for their formation from α-pinene is suggested. Cell-free extracts of the culture lines converted [14C] IPP into geraniol, nerol and α- and β-pinenes in up to 46% total yield. These are the most active crude extracts for monoterpene biosynthesis that have been reported from either tissue cultures or higher plants.  相似文献   

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14.
Essential oil from wood and from needles of Pinus balfouriana, growing in six geographically well-separated locations in California, was analysed by GLC. Several monoterpenoid components, in particular -pinene from needles, were found to be usable for distinguishing between trees from the northern and southern parts of the geographic range. Similarity coefficients were calculated and dendrograms constructed. These demonstrated the distinct separation of the northern from the southern populations, and thus substantiated the proposal by Mastrogiuseppe to regard the southern populations as a subspecies. While the northern populations exhibited a tendency to produce larger seeds with longer wings, the difference was of only moderate diagnostic value.  相似文献   

15.
The essential oils of five Tanacetum vulgare genotypes were investigated and their main components identified. Artemisia alcohol, γ-campholenol, davanone, lyratol, lyratyl acetate and 4-thujen-2α-yl acetate have not been reported before as constituents of Tanacetum vulgare. This is the first time that γ-campholenol has been isolated from a natural source. 4-Thujen-2α-yl acetate is a novel compound.  相似文献   

16.
The changes in the relative amounts of the mono- and sesquiterpenes of the volatile oil of the leaves, buds and twigs of black spruce were determined at various intervals throughout the year. Major changes take place in the young leaves just after bud burst until mid-summer. Upon maturing the same quantitative composition as that of the mature leaves is reached. The composition of the latter, as well as that of the twigs, shows only minor changes from bud burst to mid-summer and none during the rest of the year. In contrast, large relative quantitative changes take place in the bud oil throughout the year. The relative changes of santene, tricyclene, camphene, bornyl acetate and limonene in the new growth follow similar curves, but those of α-pinene, β-pinene, myrcene, car-3-ene and the sesquiterpenes differ considerably. The sesquiterpenes, and possibly myrcene, appear to be metabolized at least in part as the young leaves mature.  相似文献   

17.
Vapor-phase chromatographic patterns obtained from the essential oils from three populations of Thymus villosus subsp. lusitanicus are discussed. Two infraspecific chemovars and two chemoforms can be distinguished.  相似文献   

18.
The composition of the volatile fraction of four pine resins has been studied before and after an ‘ageing’ process. Typical terpenes of Baltic Amber were detectable after this ‘ageing’ process.  相似文献   

19.
探讨了自 2 0 0 0年 9月到 2 0 0 1年 1月来自安徽省霍邱县地区原发性高血压人群中α Adducin基因单核苷酸多态性与血清中总胆红素、直接胆红素和间接胆红素含量的相关性。在原发性高血压女性患者中 ,在校正了许多可能影响胆红素含量的重要因素后 ,与携带有Gly4 6 0Gly基因型的高血压女性患者相比较 ,携带有Trp4 6 0Trp基因型的高血压女性患者血清平均总胆红素 (β =- 1 2 μmol/L ;P =0 0 1)、直接胆红素 (β =- 0 4 μmol/L ;P =0 0 2 )和间接胆红素 (β=- 0 8μmol/L ;P =0 0 3)的含量比较低。在女性中抽取总胆红素、直接胆红素和间接胆红素含量最高和最低的各 2 5 % ,在校正了重要的变量后发现携带Trp/Trp基因型的女性比Gly4 6 0Gly基因型的女性有更大的可能性血清总胆红素含量 (OR值 =4 0 ;95 %可信区间 :1 6~ 10 2 ;P <0 0 1)、直接胆红素含量 (OR值 =4 0 ;95 %可信区间 :1 6~ 9 7;P <0 0 1)和间接胆红素含量 (OR值 =2 7;95 %可信区间 :1 1~ 6 7;P =0 0 3)更低。然而 ,在男性高血压患者中没有发现任何明显的相关性。以上的结果认为在中国原发性高血压女性患者中 ,Trp/Trp基因型与低的血清胆红素含量有直接关系 ,因为Trp/Trp基因型的女性的低血清胆红素 ,进而认为也许增加了患心血  相似文献   

20.
Although all parts of the geranium plant (Pelargonium hortorum) are capable of synthesizing sterols and triterpenes and their esters in vitro from mevalonic acid-[2-14C], the aerial portions are more active than other tissues. All plant parts were shown to incorporate mevalonic acid-[2-14C] into isoprenoids for at least 3 days. The leaves and petioles had the greatest incorporation on a wet weight basis. Chopped preparations showed comparable incorporations of mevalonate whereby rootlets incorporated about one half as much as most parts; the flower petals incorporated five times the average amount. In leaves the principal sterol synthesized was sitosterol. Metabolic studies with isolated leaves indicated a fairly rapid conversion of free tetracyclic triterpenes to 4-desmethyl-sterols, while β-amyrin was synthesized at a different rate than α-amyrin. Esterified tetracyclic triterpenes exhibited only a slight amount of conversion to 4-desmethylsterols.  相似文献   

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