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21.
Curcumin (CMN) is the principal active component derived from the rhizome of Curcuma longa (Curcuma longa L.). It is a liposoluble polyphenolic compound that possesses great therapeutic potential. Its clinical application is, however, limited by the low concentrations detected following oral administration. One key strategy for improving the solubility and bioavailability of poorly water-soluble drugs is solid dispersion, though it is not known whether this technique might influence the pharmacological effects of CMN. Thus, in this study, we aimed to evaluate the antioxidant and antigenotoxic effects of CMN formulated in a solid dispersion (CMN SD) compared to unmodified CMN delivered to Wistar rats. Cisplatin (cDDP) was used as the damage-inducing agent in these evaluations. The comet assay results showed that CMN SD was not able to reduce the formation of cDDP-DNA crosslinks, but it decreased the formation of micronuclei induced by cDDP and attenuated cDDP-induced oxidative stress. Furthermore, at a dose of 50 mg/kg b.w. both CMN SD and unmodified CMN increased the expression of Tp53 mRNA. Our results showed that CMN SD did not alter the antigenotoxic effects observed for unmodified CMN and showed effects similar to those of unmodified CMN for all of the parameters evaluated. In conclusion, CMN SD maintained the protective effects of unmodified CMN with the advantage of being chemically water soluble, with maximization of absorption in the gastrointestinal tract. Thus, the optimization of the physical and chemical properties of CMN SD may increase the potential for the therapeutic use of curcumin.  相似文献   
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Reducing chemical fertilizer while remaining high crop yield has become a trend of agricultural practice. The purpose of this study was to investigate the effects of nitrogen (N) input on the structure of the fungal community and mycorrhizal inoculum potential in rhizosphere of Curcuma longa, aiming to minimize the use of chemicals and optimize the effect of biofertilizer for sustainable turmeric farming. For this, a field study was conducted in two successive years 2015 and 2016 with applications of varrying N fertilizer rates N0 (0 kgN ha?1 y?1), N150 (150 kgN ha?1 y?1), N350 (350 kgN ha?1 y?1), and N500 (500 kgN ha?1 y?1) in combination with mycorrhizal biofertilizer on turmeric plants in Hung-Yen. Rhizosphere soils were then analyzed for the abundance of predominant fungal taxon based on amplicon sequencing of rDNA internal transcribed spacer regions. Metagenomic results indicated significant effects of N inputs on rhizosphere fungal communities composition, with dominance of ascomyceteous fungi under optimized N levels, whereas basidiomycetous fungi were more abundant under higher N input. Operational taxonomic units relating to the predominantly abundant genus Glomus were found apparently in higher proportion under optimized N inputs (N150). The results demonstrate an enhanced productivity and icreased mycorrhizal inoculating potential by appropriated N fertilizer application in turmeric rhizosphere.  相似文献   
23.
The stereochemistry and mechanism in the reduction of the C–C double bond of carvone by the cultured cells of Astasia longa, a nonchlorophyllous cell line classified in Euglenales, was studied. The reduction of the C–C double bond of carvone with the cultured cells involved the anti-addition of hydrogen atom from the si face at the -position and the re face at the β-position of carbonyl group. Two different enone reductases were isolated from the cultured cells of A. longa. Both reductases catalyzed stereospecifically the anti-addition of hydrogen atoms from the si face at C-1 and the re face at C-6. However, one of the reductases participated in a hydrogen transfer of the pro-4R hydrogen of NADH to C-6 position of carvone and the other used the pro-4S hydrogen of NADH.  相似文献   
24.
目的了解姜黄植物根茎中内生真菌群落组成和生态分布规律。方法采用表面消毒法分别于春、冬季从姜黄植物根茎中分离内生真菌,通过形态特征和基于ITS序列的系统发育分析初步确定其分类地位。结果分离获得51株内生真菌(春季33株、冬季18株),初步鉴定其分别归于5个纲、7个目、8个科、8个属(Fusarium,Gibberel-la,Alternaria,Phomopsis,Diaporthe,Nectria,Botryosphaeria,Mucor),其中镰刀菌属(Fusarium,51.0%)和赤霉属(Gibberel-la,17.6%)为优势菌群;春季分离的内生真菌分属于7个属(分离率为82.5%),而冬季的内生真菌仅归入4个属(分离率为45.0%)。结论姜黄植物中内生真菌具有较丰富的物种和系统发育多样性,在类群组成和分布上存在季节性差异,某些内生真菌(Fusariumsp.)具有宿主偏好性。  相似文献   
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利用 3′ RACE和 5′ RACE技术 ,从腐生型眼虫长变胞藻 (Astasialonga)克隆了磷酸丙糖异构酶(TIM)的两个同工酶cDNA全序列。分析表明 :它们分别编码定位于细胞质的胞质型TIM (cTIM)和定位于质体的质体型TIM (pTIM) ;后者的N端具有引导该酶定位到质体中去的典型“前导序列”。根据这些事实我们推测腐生型眼虫A .longa质体中可能存在功能性的TIM ,并进一步认为该质体可能不只是一般意义上的“叶绿体退化的残迹” ,而仍是一种至少有TIM参与其代谢活动的功能性细胞器  相似文献   
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ABSTRACT

We wished to search for the compounds contributing to the anti-inflammatory effects of the water extract of Curcuma longa (WEC). WEC was fractioned and the fractions were evaluated with regard to their inhibitory effect on the production of nitric oxide (NO) from the macrophage cell line stimulated by lipopolysaccharide. Compounds in the active fractions were isolated and identified. One isolated compound was identified as new: (6S)-2-methyl-5-hydroxy-6-(3-hydroxy-4-methylphenyl)-2-heptene-4-one (1). Four isolated compounds were identified as known: (6S)-2-methyl-6-(4-hydroxyphenyl)-2-heptene-4-one (4), bisabolone-4-one (5), curcumenone (6), and turmeronol A (8). Three isolated compounds were not identified their stereostructures but their planar structures: 2-methyl-6-(4-hydroxymethyl-phenyl)-2-heptene-4-one (2), 2-methyl-6-(2,3-epoxy-4-methyl-4-cyclohexene)-2-heptene (3), and 4-methylene-5-hydroxybisabola-2,10-diene-9-one (7). Compounds 1, 4, 7 and 8 inhibited production of prostaglandin E2 and NO. Others inhibited NO production only. These results (at least in part) show the active compounds contributing to the anti-inflammatory effects of WEC, and may be useful for elucidating its various beneficial physiologic effects.  相似文献   
29.
Carboxylesterases (CE), expressed at high levels in human liver and intestine, are thought to detoxify xenobiotics. The goal of this study was to study the effect of phenolic compounds from several plants from the Algerian Atlas used traditionally in Arab folk medicine on the enzymatic activity of porcine liver carboxylesterase. The plants have shown a potent inhibition of carboxylesterase (CE) enzymatic activity in a concentration-dependent manner. Results indicate that the Phenolic extracts from these plants lead to the inactivation of the CE pI = 5.1 with Ki values in micromolar range (1.4–38 μM). These results encourage further biological investigation and identification the inhibitors responsible for this activity.  相似文献   
30.
The brown marmorated stink bug Halyomorpha halys is an invasive agricultural pest in North America and Europe, and also a dwelling nuisance in autumn, due to the overwintering adults aggregating inside buildings. The repellent potential of ginger, clove, vetiver and turmeric essential oils (EOs) was tested on H. halys adults of three different physiological-behavioural phases: exiting overwintering (EXOV), active during summer (SUMM) and entering overwintering (ENOV). In a two-choice apparatus, fresh food was used as an attractant in both sides, together with three males when testing ENOV individuals. A filter paper with different concentrations of the EOs was the treatment side, and a filter paper with ethanol acted as control. The position of the individually tested bugs was recorded after 1, 6 and 24 hr. All tested EOs were repellent at concentrations higher than 3%, independent of sex or length of exposure. Turmeric and clove were the most repellent EOs, whereas ginger and vetiver showed on average a medium-to-low repellency. Significant differences emerged among the physiological-behavioural phases, with SUMM individuals showing a greater repellency to many of the tested concentrations, and EXOV individuals being overall the least susceptible to these substances. The response to vetiver oil was ambiguous, as at 25%, it elicited both a strong repellency in SUMM and a strong attraction in EXOV. Turmeric and clove EOs are promising candidates in integrated pest management strategies to reduce attacks by H. halys to susceptible crops especially during summer, as well as to prevent the entrance of overwintering bugs in buildings in autumn.  相似文献   
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