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1.
The fatty acids of a strain of Diasporangium sp.had been analyzed by using GC-MS.The fatty acids of twenty mutants were determined.Based on these results,the producing of eicosapentaenoic acid（EPA）supposed via 18∶2,18∶3,20∶3,20∶4 which all belong to ω-6 fatty acids.The ω-3 desaturation was undertaken at arachidonic acid（AA）.In addition,mutant strains resulted in enhanced content of AA which could get two times more than initial strain,but no compact on EPA.  相似文献   

2.
In this study, production of ct-linoleic acid concentrated from crude perilla oil by gradient cooling urea inclusion was optimized. The fatty acid composition was determined after ethyl esterification by gas chromatography （GC）. In this process, orthogonal experiment was carried out. Under optimum conditions, the maximum amount of α-linoleic acid （91.5%） was obtained at a urea to fatty acid ratio of 3, a solvent to fatty acids ratio of 7, a reaction temperature of 348 K and a crystallization time of 690 min. A simple method of gradient cooling urea inclusion was used to purify α-linolenic acid by using urea to form inclusion complexes with the saturated and the less unsaturated fatty acids, which enhanced the purity of α-linoleic acid ethyl ester by above 90%.  相似文献   

3.
Oleanolic acid （OA） and ursolic acid （UA） are isomeric tritcrpenes that are difficult to separate chromatographically. Studies have indicated that both OA and UA have antifertility properties in several livestock species, suppressing attainment of puberty, gonad function and gamete production. Being able to determine the presence and quantity of the OA and UA in moringa and pawpaw seeds will allow for calculation of optimal inclusion levels of these acids in animal diets for antifertility-activity. The purpose of the study was thus to quantify the levels of OA and UA in Moringa and pawpaw seed powder by means of ultra-high performance liquid chromatography with electrospray ionization tandem mass spectrometry （UHPLC-ESI-MS/MS）. Only OA was detected in moringa seeds at a concentration level of 0.508 p.g/g ＋ 0.032 pg/g dry weight. UA and OA could not be detected in pawpaw seeds used in this study. The presence of OA in moringa seeds suggest that the seeds can be included in tilapia diets as a potential antifertility treatment to control precocious breeding in tilapia culture in small scale farming systems in Sub-Saharan Africa. Further studies are warranted to determine the levels of OA and UA composition in moringa seeds from other parts of the Sub-Saharan Africa （other than Zambia）.  相似文献   

4.
A new chemical index-imbalance degree(IBD),was proposed on the basis of cluster analysis in multivariate statistical analysis to estimate the extent of amino acid balance in protein.The range of IBD is between 0 and 1,successively corresponding to complete baance and entire imbalance for the amino acid profile of a sample.The amino acid increment model of IBD belongs to an asymmetrical maximum-type,and there is a high correlation between IBD and coefficient of variation(CV),The nutritional Value of individual feed can be ranked and clustered according to its IBD;and by calculating the IBD of amixed sample with two or more feedstuffs,it is possible theoretically to predict whether a synergetic phenomenon exists and when an optimal mutual complement can happen.If the conceptive frame of IBD extended,it can be used to study the balance of plement can happen.If the conceptive frame of IBD extended,it can be used to study the balance of nutrients besides amino acids,and is helpful to realize the automatic distinction and selection in diet formulating.  相似文献   

5.
The feeding trial was conducted to determine the effects of flaxseed on layer＇s performance and egg quality, and the effects of the dietary ratio of ω-6 fatty acid to ω-3 fatty acid on fatty acid deposition in yolk using flaxseed as resource of ω-3 fatty acid and sunflower seed as resource of ω-6 fatty acid. 192 20-wk-old Newroman commercial hens were randomly divided into 4 treatment groups with 6 replicates containing 8 birds. The rations corresponding with the four treatments were formulated with 4% flaxseed ＋ 9% sunflower seed, 8% flaxseed ＋ 18% sunflower seed, 15% flaxseed, and soybean meal, respectively. Sunflower seed was unshelled and flaxseed was whole. Ratios of ω-6 fatty acid to ω-3 fatty acid in 4 dietary treatments were 5.67, 5.21, 1.07, and 11.83, respectively. It can be concluded that long-term feeding 15% flaxseed had no significant （P〉 0.05） influence on egg production, egg weight, eggshell quality, yolk weight, and percentage of yolk weight. Dietary ratio of ω-6 fatty acid to ω-3 fatty acid had impact on the 0-3 fatty acid levels in yolk, nevertheless yolk fatty acid profiles were different from those of dietary fatty acid compositions.  相似文献   

6.
A corn-soybean meal diet （CSB） （or Diet 1） containing 23% crude protein （CP） was used as the positive control, and another corn-soybean meal diet containing 21% CP and 15% wheat middlings （WM） （or Diet 2） was used as the basal diet, which was treated with four different treatments. Digestibility experiment was employed to discuss the collective effect of citric acid, and intrinsic and microbial phytase. By comparing and analyzing effects of them in the low-nutrient broiler diets, the results showed five treatments had similar effects on Tibia ash （%） （mg） （P〉0.05）. Under the supplementation of bacterial phytase or citric acid, the daily body weight gain （ADG）, gain：feed （G：F） ratio, and calcium （Ca） utilization were similar to that of standard-nutrient CSB diet （Diet 1） （P 〉 0.05）. And, fecal phosphorus （P） and CP utilization were lower than （P〈0.05） that of Diet 1. But P utilization was significantly higher than （P〈0.01） that of Diet 1. However, the ADG, G：F, and CP utilization produced by supplementation of intrinsic phytase were lower than those of Diet 1, but other aspects were similar to those produced by Diet 1 （P〉0.05）. In Diet 5, citric acid, intrinsic and bacterial phytase were added to the diet, which produced a 1.4% decrease on fecal P, a 7.2% increase on Ca utilization, which was significantly higher than （P〈0.01） those of the other four Diets, a 3.9% increase on G：F, which was similar to that of Diet 1, and a 2.3% increase on CP utilization, which was higher than （P〈0.05） that of the other three diets. In summary, the results of this study indicated that citric acid, intrinsic and bacterial phytase might have some additive or synergistic effects, and low-nutrient CSB diets with 15% wheat middlings, 750 U kg^-1 phytase, and 3% citric acid might substitute completely for standard CSB in broilers.  相似文献   

7.
The effects of kojic acid on phenoloxidase (PO) of Plutella xylostella were investigated, when it had been partially purified by 40% saturated [(NH4)2SO4] and Sephadex G-100 gel filtration. Kojic acid showed inhibitory effects on both monophenolase and o-diphenolase activity of the PO. The inhibitor concentrations leading to 50% (IC50) activity lost were estimated to be 0.07 mmol L^-1 for monophenolase and 1 mmol L^-1 for diphenolase, respectively. Kojic acid can also prolong the lag time of PO for oxidation of L-tyrosine. The inhibition kinetics were analyzed by Lineweaver-Burk plots and kojic acid was found to be a reversible competitive inhibitor with the ki of 0.47 mmol L^-1. The ability of kojic acid to inhibit the enzyme activity may be associated with its ability to chlate copper at the active site. In addition, the iron ion was found to shorten the lag time obviously, but have no important effect on the monophenolase activity.  相似文献   

8.
Intramuscular fat （IMF） content is considered to be a key factor that affects the marbling, tenderness, juiciness and lfavor of pork. To investigate the effects of myristic acid （MA） on the differentiation of porcine intramuscular adipocytes, cells were isolated from longissimus dorsi muscle （LDM） and treated with 0, 10, 50 or 100μmol L-1 MA. The results showed that MA signiifcantly promotes the differentiation of intramuscular adipocytes in a dose-dependent manner. MA also led to a parallel increase in the expression of peroxisome proliferator activated receptor-γ（PPARγ） and adipose-related genes, such as glucose transporter 1 （GLUT1）, lipoprotein lipase （LPL）, adipocyte fatty acid binding protein 4 （FABP4/aP2）, fatty acid translocase （FAT）, acetyl-CoA carboxylaseα（ACCα）, adipose triglyceride lipase （ATGL） and fatty acid synthase （FASN）. However, no signiifcant effects of MA were observed on the expression of CAAT enhancer binding protein-α（C/EBPα） or hormone sensitive lipase （HSL）. The expression of pyruvate dehydrogenase kinase 4 （PDK4） was increased by MA during the early stages of differentiation （day 1-3）. In addition, MA also increased the absolute content of C14 （P〈0.001） and saturated fatty acids （SFA） （P〈0.05） to varying degrees, but no effects were observed on other fatty acids. These results suggest that MA might be able to enhance the IMF content of pork and increase the accumulation of myristic and myristoleic acid in muscle, which might have beneifcial implications for human health.  相似文献   

9.
To investigate the antibacterial activity of commercial organic acid Activate WD (WD), the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of WD against Staphylococc...  相似文献   

10.
Seedling of five canola genotypes, Hyola 308, Hyola 401, Hyola 60, Option 50 and RGS003, were grown in Hoagland nutrient solution containing S1 = 0, S2 = 100, S3 = 200 and S4 = 300 mmol L-1 NaCl in controlled environment. Proline, antioxidant activities like catalase （CAT）, ascobrate peroxidase （APX） and guaiacol peroxidase （GPX） and some enzyme activities of nucleic acid metabolism were determined in shoot and root 20 days after induction of salinity stress. Results showed application of stress significantly affected plant growth components such as fresh （FW） and dry weight （DW） of canola genotypes. Among the genotypes, RGS003 had the highest reduction of FW and DW in S3 treatment. By increasing NaCl levels from 0 to 300 mmol L-1, the activity of two antioxidant enzymes （APX and CAT） in shoot and root increased but GPX in all of genotypes decreased. The increase in salinity stress, increased proline concentration in both root and shoot tissues of canola genotypes. Hyola 401 genotype had the maximum concentration of proline in root and shoot in S3 treatment. Along with increased salinity stress in all of the studied plants, salinity significantly increased the level of the total nucleic acid and the activity of DNase I in all of salinity treatments and at the S3 level, RGS003 had the maximum concentration of nucleolytic enzyme.  相似文献   

11.
The purpose of this article is to study the effects of different water elevations of non-pressure subirrigation on some indexes of tomato, including soil water status around crop rootzone, morphological indexes, physiological indexes, photosynthetic indexes, yield, quality, and water use efficiency. With the tomato materials of Dongsheng 1, the irrigation experiment was carried out in the greenhouse, and significance analysis was done on the experiment data through the software of DPS. The results showed that different water elevations, had significant influence on the growth, yield, and quality of tomato. The yield of the 6-cm treatment was the highest, the 3-cm treatment was inferior to the 6-cm treatment, and the 0-cm treatment was the lowest. However, the WUE was 0 cm 〉 3 cm 〉 6 cm. The sugar/acid and soluble protein was the highest under the 0-cm treatment, and the content of ascorbic acid did not decrease considerably. When compared to the 0-cm treatment, the ascorbic acid content of 6-cm and 3-cm treatment increased by 19.2 and 6.8%, respectively. These irrigation methods can satisfy the requirements of tomato growth; different water elevations have different influences on the tomato soil water status around crop rootzone, the physiological characteristics, and yield. It also harmonized the percentage between sugar and acid, increased the content of soluble protein and ascorbic acid, and made tomato more delicious. The irrigation methods can improve the quality of tomato by water control, which is worth promoting in the agricultural production.  相似文献   

12.
Fruit sugar and acid content were determined in a group of hybrids from one family,including 22 peach and 85 nectarine genotypes, or 75 white-fleshed and 32 yellow-fleshed genotypes. Sucrose accounted for about 65% of the total sugar, and malate for about 50% of the total acid. Mean sucrose, fructose, sorbitol, total sugar, soluble solid and quinate content were significantly higher in nectarines than in peaches, while no significant difference was found in mean malate, citrate and total acid content between nectarines and peaches. Shikimate content was very low and ranged from 0.011-0.046 meq 100 g^-1 FW in all genotypes studied. Flesh color did not affect sugar and acid content.Glucose and fructose had a close positive correlation (r=0.63***). Malate had positive correlations with sucrose, sorbitol, total sugar and soluble solid content. The correlation between citrate and sugars were not significant. Glucose, fructose, sorbitol and malatecontent seemed to be higher in late-maturing genotypes. Sucrose, total sugar and total acid content had a parabolic relationship with developmental period (from full blooming date to maturity date).  相似文献   

13.
《农业科学与技术》2013,(10):1476-1481
[Objective] The paper was to evaluate effects of peracetic acid （PAA） combined with calcium treatments on storage quality of Ioquat fruits, so as to pro- vide practical techniques to solve the problems of postharvest rot and quality deteri- oration for Ioquat fruits. [Method] With Ioquat fruits of Qingzhong variety as materi- als, 0.2%, 0.4% and 0.8% PAA combined with 0.8% CaCI2 was used to soak Ioquat fruits for 4 min, 0.8% CaCl2 and water treatments were set as two controls; the fruits were dried and packaged by 0.02 mm PE bags, then stored under non-chilling low temperature of （7±1） ℃. The indicators related to storage quality of Ioquat fruits were randomly tested once every 3 d, and their variation situations were analyzed. [Result] Compared with two control treatments and 0.2% PAA, 0.8% PAA combined with calcium treatments, the treatment of 0.4% PAA combined with 0.8% CaCl2 could significantly inhibit rot index, weight loss rate, firmness and cell membrane permeability of Ioquat fruits during storage period, which could also effectively delay the reduction of titratable acid, vitamin C, soluble solid content and juice yield, and maintain respiration intensity of fruits at a low level; the appearance and flavor qual- ity of fruits were good after stored for 25 d. [Conclusion] 0.4% PAA combined with 0.8% CaCl2 treatment is an efficient, safe and economical practice technology in an- ti-corrosion and quality preservation for postharvest Ioquat fruits .  相似文献   

14.
2,4-dienoyl CoA reductase gene(DECR 1)is mapped on pig 4 q 1.2,includes ten exons and nine introns of variable size that span 30 kb.DECR 1 gene participates in theβ-oxidation pathway,affects the content of intramuscular fatty acid,especially the percentage of linoleic acid.The expression of DECR 1 gene has important influence on IMF,the pH,and the meat colour of pork, further affects the meat quality.  相似文献   

15.
In the literature there are many reports on the composition and properties of pumpkin seed oil; however, few is known about the effect of different stages of seed development on various fatty acid profiles in developing seeds. The objective of this study was to provide the changes of various fatty acid accumulations in seed oil obtained from the seeds of three pumpkin varieties belonging to the species Cucurbita maxima and Cucurbita pepo. Unsaturated acids (oleic and linoleic) were dominant in various fatty acids, which constituted 38.9%-49.1% and 29.4%-42.7% of the total fatty acids at seed maturity for three pumpkin varieties, respectively, while other fatty acid concentrations except for palmitic acid all did not reach 10%. Different varieties exhibited greater effect on various fatty acid contents and the total fatty acid contents in the seeds of pumpkin rather than the species. On the whole, palmitic acid profiles of the seed oil in three varieties all followed the fluctuant decrease during all the stages of seed development, but palmitoleic acid and the total fatty acid profiles of the seed oil in three varieties were just the opposite. Stearic, oleic and linoleic acid profiles of the seed oil in three varieties all experienced the third pattern that fluctuated during all the stages of seed development, but no significant differences in these three fatty acid concentrations were found from the beginning to the end. Linolenic acid concentrations of three varieties were on the decline and ultimately close to zero. Myristic and arachidic acid profiles of the seed oil followed different trends in three varieties. Among them, myristic and arachidic acid profiles of the seed oil of Yinhui-1 fluctuated downward all the time until seed maturity, but those of 0238-1 and Jinhui-2 completely changed oppositely.  相似文献   

16.
To study differences and genetic trends of volatiles in Xingdu 1 and Xingdu 2, the strawberry cultivars, with their parents, the volatile components were analyzed by head space-solid phase microextraction and gas chromatography-mass spectrometry. The results indicated that a total of 50 compounds were identified in Xingdu 1 cultivar, including hexanoic acid methyl ester and hexanoic acid ethyl ester, butanoic acid methyl ester, and butanoic acid ethyl ester, octanoic acid methyl ester and octanoic acid ethyl ester, isomyl hexanoate. And there were 71 compounds in Xingdu 2, which were similar to that of Xingdu 1. About 55 volatiles were identified in Allstar （female parent）, including acetone, acetic acid 1- methylethyl ester, 1-octanol, hexanoic acid ethyl ester and butanoic acid methyl ester. And 43 volatiles were identified in Toyonoka （male parent）, including hexanoic acid ethyl ester, nerolidol, 1-octanol, hexanoic acid methyl ester, acetic acid octyl ester, isomyl hexanoate and octanoic acid methyl ester. Consequently, hexanoic acid methyl ester and hexanoic acid ethyl ester, butanoic acid methyl ester, and butanoic acid ethyl ester and isomyl hexanoate in twins might be affected both sides of their parents. In the family, male parent （Toyonoka） had the highest concentrations of fragrance alcohols, such as nerolidol, linalool and 1-octanol, but which couldn＇t be transmitted to the descendants. Acetone, acetic acid 1- methylethyl ester of the twins originally came from matrilinear inheritance, as the contents of the two compounds were very high in Allstar but little in Toyonoka. Genetic trends of butanoic acid methyl ester, butanoic acid ethyl ester, hexanoic acid ethyl ester, hexanoic acid methyl ester and isomyl hexanoate were affected by both sides of parents.  相似文献   

17.
This study investigated the effects of the degree of unsaturation(unsaturity) of long-chain fatty acids on microbial protein content and the activities of transaminases and dehydrogenase in vitro using goat rumen fluid as the cultural medium.Six types of fatty acids,stearic acid(C18:0,group A,control group),oleic acid(C18:1,n-9,group B),linoleic acid(C18:2,n-6,group C),α-linolenic acid(C18:3,n-3,group D),arachidonic acid(C20:4,n-6,group E),and eicosapentaenoic acid(C20:5,n-3,group F),were tested,and the inclusion ratio of each fatty acid was 3%(w/w) in total of culture substrate.Samples were taken at 0,3,6,9,12,18 and 24 h,respectively,during culture for analyses.Compared with stearic acid,linoleic acid,a-linolenic acid,and arachidonic acid increased the bacterial protein content,while oleic acid and eicosapentaenoic acid had no significant effects;the protozoal protein content was reduced for all the unsaturated fatty acids,and the magnitude of the reduction appeared to be associated with the degree of unsaturity of fatty acids.The total microbial protein content was dominantly accounted by the protozoal protein content(about 4-9 folds of the bacterial protein),and only increased by linoleic acid,but reduced by oleic acid,arachidonic acid and eicosapentaenoic acid.There were no significant effects in the activities of both glutamic oxaloacetic transaminase(GOT) and glutamic-pyruvic transaminase(GPT) for all the other fatty acids,except for arachidonic acid which enhanced GOT activity and oleic acid which enhanced GPT activity.The total dehydrogenase activity was positively correlated with the degree of unsaturation of fatty acids.In conclusion,the inclusion of 3%of long-chain unsaturated fatty acids increased bacterial protein content,whereas reduced protozoal protein content and enhanced dehydrogenase activity.The fatty acids with more than three double bonds had detrimental effects on the microbial protein content.This work demonstrates for the first time the effect rule of the unsaturation degree of long-chain fatty acids on the rumen microbial protein in vitro.  相似文献   

18.
The experiment was designed to study effects of retinoic acid and ascorbic acid on differentiation of mouse embryonic stem cells to cardiomyocytes. Embryonic bodies(EB) were developed from m ESC in suspension culture, different levels of concentration of retinoic acid and ascorbic acid were used to determine the optimal conditions for EB formation. The results showed that the optimal concentrations were 10-9 mol · L-1 and 0.1 mg · m L-1 for retinoic acid and ascorbic acids, respectively. 50% of EB which was significantly(p0.05) different from the control group developed to cardiomyocytes. In conclusion, retinoic acid and ascorbic acid had strong ability to promote cardiomyocyte differentiation of mouse embryonic stem cells. 10-9 mol · L-1 retinoic acid and 0.10 mg · m L-1 ascorbic acids were recommended to induce differentiation of mouse ES cells toward cardiomyocytes.  相似文献   

19.
盐胁迫对水稻幼苗类囊体膜脂肪酸组分的影响(英文)   总被引：11，自引：3，他引：8  
[Objective] The aim of the study is to understand the changes of fatty acid composition of rice thylakoid membrane under salt stress.[Method] Under salt stress of different concentrations of NaCl,rice seedlings of Pokkali and Peta with six leaves and one central leaf were used as experimental materials to extract the fatty acid from their thylakoid membranes,and gas chromatograph(1890)was used to analyze fatty acid composition.[Result] Fatty acid component 14∶0,18∶0,16∶1(3t),18∶1 in both the two experimental materials showed little variations in the first four days of salt stress,whereafter they increased slightly;while the fatty acid component 16∶0 and level of saturation of fatty acid(LSFA)showed the similar variation trend in the first four days of treatment compared to those of the fatty acid components mentioned above,whereafter they rose in Pokkali and presented an opposite variation trend in Peta;fatty acid component 18∶3 and level of unsaturation of fatty acid(LUFA)reduced all the time under stress condition,and the reducing amplitude in 100 mmol/L NaCl treatment group was smaller than that of 100 mmol/L NaCl treatment group,and in Pokkali was smaller than that in Peta under specific conditions.Meanwhile,level of saturation of fatty acid in both experimental materials increased,and the rising amplitude in Peta was smaller than that of Pokkali.[Conclusion] With regard to LUFA,Pokkali is endowed with more salt tolerance than Peta.  相似文献   

20.
[Objective] The aim of the study is to understand the changes of fatty acid composition of rice thylakoid membrane under salt stress.[Method] Under salt stress of different concentrations of NaCl,rice seedlings of Pokkali and Peta with six leaves and one central leaf were used as experimental materials to extract the fatty acid from their thylakoid membranes,and gas chromatograph(1890)was used to analyze fatty acid composition.[Result] Fatty acid component 14∶0,18∶0,16∶1(3t),18∶1 in both the two experimental materials showed little variations in the first four days of salt stress,whereafter they increased slightly;while the fatty acid component 16∶0 and level of saturation of fatty acid(LSFA)showed the similar variation trend in the first four days of treatment compared to those of the fatty acid components mentioned above,whereafter they rose in Pokkali and presented an opposite variation trend in Peta;fatty acid component 18∶3 and level of unsaturation of fatty acid(LUFA)reduced all the time under stress condition,and the reducing amplitude in 100 mmol/L NaCl treatment group was smaller than that of 100 mmol/L NaCl treatment group,and in Pokkali was smaller than that in Peta under specific conditions.Meanwhile,level of saturation of fatty acid in both experimental materials increased,and the rising amplitude in Peta was smaller than that of Pokkali.[Conclusion] With regard to LUFA,Pokkali is endowed with more salt tolerance than Peta.  相似文献   

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