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1.
植物二酰甘油酰基转移酶基因(DGAT)研究进展   总被引:2,自引:0,他引:2  
三酰甘油(TAG)是油料作物最主要的储藏脂类,二酰甘油酰基转移酶(DGAT,EC2.3.1.20)是TAG合成途径的限速酶,其主要作用是催化二酰甘油加上酰基脂肪酸形成三酰甘油.在植物中已发现了3种不同类型的DGAT基因,分别为DGAT1、DGAT2和DGAT3.该文对近年来国内外有关植物DGAT相关基因及其蛋白分类、定位、结构及其在脂肪酸合成、种子发育与萌发、幼苗发育、叶片新陈代谢等过程中的作用等研究进展进行综述.为提高油料作物种子油含量以及特定脂肪酸积累提供理论参考.  相似文献   
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Olive oil history,production and by-product management   总被引:1,自引:0,他引:1  
In this review paper, the history of the olive tree and the development of the main olive oil extraction systems employed in the past are presented. Furthermore, the management techniques employed from antiquity until today for the treatment of olive mill wastewater (OMW), which constitutes the most important by-product of olive oil production, are addressed and compared. Reference is also made to global olive oil production, the environmental impacts of the uncontrolled disposal of OMW, and to the legal framework concerning its management in the main olive oil producing countries. Other by-products of olive processing are also discussed.  相似文献   
4.
A combination of bioassay and biochemical approaches were used to determine toxicity of Artemisia annua essential oil (AaEO) Pseudococcus viburni. AaEO via leaf dipping bioassay showed LC50 values of 0.693 and 0.419% after two time exposures. Different concentrations of AaEO caused deterrence index between 28.58 to 86.26% by the calculated ED50 of 0.4%. Although, α-esterase activity using α-naphtyl acetate increased in the treated nymphs by AaEO after 24 hours but it showed the lower activity in the treated nymphs using β-naphtyl acetate. Glutathione S-transferase assayed by CDNB showed the higher activity in the treated nymphs than control after 24 hours while the adverse results gained not only after 48 hours but also after 24 hours by using DCNB. No significant differences were found in the activity of alanine aminotransferase versus control, but aspartate aminotransferase and γ-glutamyl transferase showed the statistically higher activities in the treated nymphs in comparison with control. Activities of aldolase and lactate dehydrogenase were significantly lower than those of control. Only acid phosphatase showed the significantly altered activity in the treated nymphs in comparison with control after 24 hours. Results of our study indicated significant toxicity, deterrence and physiological effects of AaEO on P. viburni.  相似文献   
5.
Conjugated linoleic acid (CLA) has attracted as novel type of fatty acids having unusual health-promoting properties such as anticarcinogenic and antiobesitic effects. The present work employed castor oil as substrate for one-pot production of CLA using washed cells of Lactobacillus plantarum (L. plantarum) and lipases as catalysts. Among the screened lipases, the lipase Rhizopus oryzae (ROL) greatly assisted resting cells to produce CLA. Mass spectral analysis of the product showed that two major isomers of CLA were produced in the reaction mixture i.e. cis-9, trans-11 56.55% and trans-10, cis-12 43.45%. Optimum factors for CLA synthesis were found as substrate concentration (8 mg/mL), pH (6.5), washed cell concentration (12% w/v), and incubation time of 20 h. Hence, the combination of ROL with L. plantarum offers one pot production of CLA selectively using castor oil as a cost-effective substrate.  相似文献   
6.
《Chirality》2017,29(2):70-79
The chirality issues in the essential oils (EOs) of leaves and flowers from Bubonium graveolens were addressed by chiral high‐performance liquid chromatography (HPLC) with polarimetric detection and vibrational circular dichroism (VCD). The chemical compositions of the crude oils of three samples were established by gas chromatography / mass spectrometry (GC/MS). The well‐known cis ‐chrysanthenyl acetate ( 1 ), oxocyclonerolidol ( 2 ), and the recently disclosed cis ‐acetyloxychrysanthenyl acetate ( 3 ), the three major chiral compounds, were isolated by preparative HPLC. The naturally occurring oxocycloneroledol ( 2 ), mostly found in the leaf oil (49.4–55.6%), presents a (+) sign in the mobile phase during HPLC on a chiral stationary phase (CSP) with a Jasco polarimetric detection. The naturally occurring cis ‐chrysanthenyl acetate ( 1 ) and cis ‐acetyloxychrysanthenyl acetate ( 3 ), mostly found in the flower EO (35.9–74.9% and 10.0–34.3%, respectively), both present a (−) sign. HPLC on a CSP with polarimetric detection is an unprecedented approach to readily differentiate the flower and leaf EOs according to their chiral signature. The comparison of the experimental and calculated VCD spectra of pure isolated 1 , 2, and 3 provided their absolute configuration as being (1S ,5R ,6S )‐(−)‐2,7,7‐trimethylbicyclo[3.1.1]hept‐2‐en‐6‐yl acetate 1 , (2R ,6R )‐(+)‐6‐ethenyl‐2,6‐dimethyl‐2‐(4‐methylpent‐3‐en‐1‐yl)dihydro‐2H‐pyran‐3(4H)‐one) 2 and (1S ,5R ,6R ,7S )‐(−)‐7‐(acetyloxy)‐2,6‐dimethylbicyclo[3.1.1]hept‐2‐en‐6‐yl]methyl acetate 3 . Compounds 1 , 2, and 3 were already known in B. graveolens but this is the first report of the absolute configuration of (+)‐ 2 and (−)‐ 3 . The VCD chiral signatures of the crude oils were also recorded.  相似文献   
7.
利用光镜及透射电子显微镜技术研究了杭白芷根中分泌道结构及其挥发油的分泌,并重点探讨分泌道中挥发油的分泌过程。结果显示:(1)杭白芷的分泌道是由上皮细胞围绕着的伸长的胞间隙,腔道内贮存着挥发油。(2)分泌道细胞的质体、细胞基质以及线粒体参与挥发油或其前体物质的合成。(3)在分泌道发育的后期,大量小泡与分泌细胞的液泡膜和细胞质膜融合,将其内的物质释放进入空腔。研究认为,杭白芷分泌道中挥发油主要合成部位为质体及细胞基质,之后以扩散渗透或通过膜质小泡与液泡及质膜融合这两种方式分泌到空腔内,丰富的线粒体可能为这一系列过程提供能量。  相似文献   
8.
The pollution of environment by toxic chemicals is a global and chronic problem. Human health risk due to exposure to chemical pollutants is constantly increasing. Pesticides form major toxic chemicals in environment. Scientifically, there is an obviously correlation between the exposure to pesticides and appearance of many diseases. Currently, the significance of natural products for health and medicine has been formidable. The present study investigated the effect of grapeseed oil in male rats exposed to diazinon. The experimental rats were divided into five groups. The rats of the first group were served as control. The experimental animals of the second group were exposed to diazinon (DZN). The animals of the third group were supplemented with grapeseed oil and treated with DZN. The rats of the fourth group were supplemented with grapeseed oil. The experimental rats of the fifth group were supplemented with corn oil. Hematobiochemical and histopathological evaluations were chosen as indicators of DZN toxicity and protective role of grapeseed oil. In rats exposed only to DZN, the levels of serum glucose, triglycerides, cholesterol, low density lipoprotein cholesterol, very low density lipoprotein cholesterol, creatinine, urea nitrogen, uric acid, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, creatine kinase and lactate dehydrogenase were statistically increased, while the level of serum total protein was significantly decreased. Moreover, the histopathological evaluations of the liver, kidney and testis showed that DZN causes several severe alterations. Pretreatment with grapeseed oil exhibited a protective role against DZN toxicity which confirmed by the inhibition of hematobiochemical and histopathological changes due to DZN exposure. Additionally, the present study suggests that the effect of grapeseed oil supplementation against DZN toxicity may be attributed to the antioxidant role of its constituents.  相似文献   
9.
In the present research, variability in essential oil (EO) composition of five Dorema aucheri populations collected from natural habitats in different regions of Iran, were investigated. The EO content of populations varied from 0.28 to 0.68%. According to gas chromatography/mass spectrometry analysis, β‐caryophyllene (7.17 – 35.73%), thymol (23.45 – 29.64%), β‐gurjunene (2.58 – 5.89%), carvacrol (1.32 – 2.67%) and cuparene (1.97 – 2.98%) were the major components. Hierarchical cluster, principal component and canonical correspondence analyses classified the studied populations into three groups based on major EO components. The environmental parameters of the collected sites were also evaluated. According to the results, it might be suggested that sandy soils with high mean annual precipitation were major environmental factors influencing the amount of β‐caryophyllene, while thymol, cuparene and caryophyllen oxide increased in silty and clay soils. Finally, the population collected in high altitudes and clay soils had higher amount of β‐gurjunene.  相似文献   
10.
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