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Essential oils content and antioxidant properties of peel ethanol extract in 18 lemon cultivars 总被引:1,自引:0,他引:1
Composition of essential oils and antioxidant activity of peel ethanol extract were analyzed in 18 local lemon cultivars. Essential oils composition was determined by GC/FID analysis, and antioxidant activity with the ABTS method. Fruit weight, polar and equatorial diameters, peel thickness, seed number, juice percentage, titratable acidity and juice pH were also determined for each cultivar. The main component in the peel essential oil was limonene, accounting for 72.5–76.4%, followed by β-pinene (11.6–18.7%). Several other monoterpene hydrocarbons were also identified at appreciable contents, namely terpinene (2.88–8.26%), α-pinene (1.4–1.5%) and myrcene (0.95–1.12%). No clear relationship could be shown between the antioxidant activity and the essential oil composition of the extracts. In this study, cultivars with higher essential oil content and antioxidant activity were identified. Data were subjected to analysis of variance using ANOVA and means were compared by the Duncan test. 相似文献
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Effect of air-drying treatment on enzymatic activities of soils affected by anthropogenic activities
Rao Maria Antonietta Sannino Filomena Nocerino Giulia Puglisi Edoardo Gianfreda Liliana 《Biology and Fertility of Soils》2003,38(5):327-332
The influence of air-drying on dehydrogenase, invertase, -glucosidase, urease, phosphatase, arylsulphatase and phenoloxidase activities was measured in three soils affected by anthropogenic activities and in control soils sampled from neighbouring areas. The air-drying changed enzyme activity, but the behaviour was neither site-specific nor enzyme-sensitive. Canonical discriminant analysis of enzymatic activities of both moist fresh and air-dried samples was able to discriminate between altered and unaltered soils irrespective of the site. Numerical alteration indices were developed as a linear function of the seven enzyme activities and the one obtained from fresh sample data was more successful. Air-drying apparently alters in unpredictable ways enzyme activities of soils, which could lead to misinterpretation of results. 相似文献
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Ginseng is the root of the perennial herbs of Panax quinquefolium and Panax ginseng which contain a series of tetracyclic triterpenoid saponins (ginsenosides) as active ingredients. It is considered a tonic or adaptogenic that enhances physical performance (including sexual), promotes vitality and increases resistance to stress and ageing. The adaptogenic properties of ginseng are believed to be due to its effects on hypothalamic-pituitary-adrenal axis, resulting in elevated plasma corticotropin and corticosteroids levels. When used appropriately, ginseng appears to be safe. Nevertheless, documented side effects include hypertension, diarrhoea, restlessness, mastalgia and vaginal bleeding. 相似文献
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Cannabis and cannabinoids exert many of their biological functions through receptor-mediated mechanisms. Two types of cannabinoid receptors have been identified, namely CB(1) and CB(2), both coupled to a G protein. CB(1) receptors have been detected in the central nervous system (where they are responsible for the characteristic effects of Cannabis, including catalepsy, depression of motor activity, analgesia and feelings of relaxation and well being) and in peripheral neurons (where their activation produces a suppression in neurotransmitter release in the heart, bladder, intestine and vas deferens). Cannabinoid CB(2) receptors have only been detected outside the central nervous system, mostly in cells of the immune system, presumably mediating cannabinoid-induced immunosuppression and antinflammatory effects. With the discovery of cannabinoid receptors for exogenous cannabinoids, also endogenous cannabinoids (anandamide, 2-arachidonylglycerol) have been described. 相似文献
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