脱臭工艺对玉米油中反式脂肪酸含量的影响

目的：研究脱臭工艺对玉米油中反式脂肪酸含量的影响。方法：在实验室内对玉米油进行不同温度和时间的脱臭处理,利用气相色谱法分析处理后玉米油中的反式脂肪酸含量。结果：脱臭温度和脱臭时间均对玉米油中反式油酸的产生影响不显著。脱臭温度对玉米油中反式亚油酸含量影响显著,脱臭时间对玉米油中反式亚油酸含量影响不显著。在一定的脱臭时间,不同脱臭温度下,玉米油中总反式脂肪酸最多含量为最少含量的80倍以上;在一定的脱臭温度,而不同脱臭时间下,玉米油中总反式脂肪酸最多含量约为最少含量的1．5倍,且在255℃以下时,随脱臭时间延长,玉米油中总反式脂肪酸的形成速度缓慢、相对含量低。结论：玉米油精炼脱臭时,对脱臭工艺装备和工艺条件中的脱臭温度进行优化选择可有效减少玉米油反式脂肪酸的产生。     

不同质量浓度NaNO3对3种微藻生长及总脂肪酸含量和组成的影响

以BG11为基本培养液,研究了不同质量浓度NaNO3(37.5～1 875.0 mg·L-1)对微藻P9(Klebsormidium sp. )、TH6(Oedocladium sp. )和CF5(Stigonema sp. )生长及总脂肪酸含量和组成的影响.结果显示,调整(减少或增加)培养液中NaNO3的质量浓度,对3种微藻的生长量及总脂肪酸含量和脂肪酸组成均有一定的影响;NaNO3的质量浓度较低(37.5或75.0 mg·L-1),3种微藻的鲜质量随培养时间的延长呈先逐渐增加然后略有降低的趋势;而在NaNO3质量浓度为150.0～1 875.0 mg·L-1的条件下,在一定的培养时间(18～33 d)内,3种微藻的鲜质量均逐渐增加;总体上看,3种微藻的生长量随NaNO3质量浓度的提高呈现逐渐增加的趋势,但仅在含1 875.0 mg·L-1 NaNO3的培养液中3种微藻的生长量高于对照(1 500.0 mg·L-1NaNO3).在含375.0 mg·L-1NaNO3的培养液中培养33 d,微藻 P9的总脂肪酸含量最高(25.39%),是对照的 1.79 倍,软脂酸、亚油酸、油酸和硬脂酸的相对含量分别是对照的2.50、2.72、2.24和2.08倍;在含37.5 mg·L-1 NaNO3的培养液中培养33 d,微藻TH6的总脂肪酸含量最高(20.69%),是对照的 1.89倍,软脂酸、亚油酸和油酸的相对含量分别是对照的3.37、1.79和1.92倍;不同处理组间微藻CF5的总脂肪酸含量及组成有一定差异,但随着NaNO3质量浓度的提高变化趋势不明显.研究结果表明,适当提高培养液中的NaNO3浓度对微藻的生长有一定的促进作用,不同种类微藻适宜的NaNO3浓度有一定的差异.综合考虑生长量和总脂肪酸含量及脂肪酸组成等因素,确定适宜于微藻P9、TH6和CF5培养的NaNO3质量浓度分别为375.0、37.5和150.0 mg·L-1.     

玉米△12脂肪酸脱氢酶基因（FAD2）在酿酒酵母中的表达

玉米△12脂肪酸脱氢酶是催化油酸形成亚油酸的关键酶。将其编码基因FAD2（GenBank登陆号：DQ496227）克隆到酿酒酵母表达载体pYES2．0中,构建成重组质粒pYE／FAD2,转化到酿酒酵母进行诱导表达,同时以pYES2．0转化子为对照。气相色谱（Gc）分析表明,重组转化子亚油酸的含量占酵母总脂肪酸的1．54％,而对照未检测到亚油酸。表明FAD2基因具有编码△12脂肪酸脱氢酶的功能。为探索转译起始密码子周边序列的改变对FAD2基因表达产生的影响,将该基因的起始密码子上游序列进行修改,构建重组表达载体pYE／FAD2—1,转化酿酒酵母进行表达。GC分析表明,pYE／FAD2—1转化子的亚油酸含量占总脂肪酸含量的8．81％,是对照pYE／FAD2转化子的近5倍。     

熊蜂成群与未成群蜂王体内氨基酸和脂肪酸含量的比较研究

为探究熊蜂Bombus spp.蜂王体内氨基酸和脂肪酸对其不同繁殖状态的影响,本研究分别利用高效液相色谱方法和气质联用方法测定成群蜂王和未成群蜂王体内氨基酸和脂肪酸的含量并进行比较分析。研究结果表明：熊蜂蜂王体内分别包含16种氨基酸和17种脂肪酸。熊蜂蜂王体内含量最多6种的水解氨基酸为谷氨酸、丙氨酸、亮氨酸、丝氨酸、天冬氨酸和苏氨酸,含量最多的3种脂肪酸为油酸、亚油酸和α-亚油酸。成群与未成群阶段熊蜂蜂王体内13种氨基酸含量存在显著差异(P<0.05),且除丙氨酸外,成群蜂王体内其余12种氨基酸含量均显著低于未成群蜂王。成群与未成群阶段熊蜂蜂王体内有6种脂肪酸含量存在显著差异(P<0.05),其中未成群蜂王体内辛酸、癸酸、月桂酸的含量较高,而成群蜂王体内亚油酸、顺-11-二十烯酸、二十三酸的含量较高。本研究结果表明,熊蜂成群和未成群蜂王体内氨基酸和脂肪酸含量存在显著差异(P<0.05),蛋白质和脂类代谢异常可能是导致熊蜂蜂王成群率低的一个主要原因。     

脱臭紫甘蓝色素“返臭”的跟踪研究

研究紫甘蓝色素经高压二氧化碳（HPCD）技术脱臭后,在贮藏过程中能否保持稳定无异味状态。采用8 MPa、50 ℃下处理60min、迅速卸压（2 min）的HPCD处理对紫甘蓝色素中异味物质进行脱除。通过气质联用（GC-MS）色谱技术,对脱臭后不同贮藏时间（3、5、10、15d）内紫甘蓝色素中的异味物质进行跟踪分析。结果表明：HPCD脱臭后的紫甘蓝色素在贮藏过程中存在返臭现象。经过15d的贮藏,对异味贡献最大的含硫化合物的相对百分含量随贮藏时间的延长呈递增趋势,由1.48%增至46.61%,该色素中的核心异味物质烯丙基异硫氰酸酯（AITC）的相对百分含量由1.06%递增至31.98%,其他异味物质的含量也不断增加。     

Mefluidide对玉米叶片线粒体膜脂组成的影响及其与抗冷力的关系

Mcfluidide叶面喷洒处理玉米幼苗,常温下可提高叶片线粒体膜脂中磷脂酰胆碱含量和脂肪酸中亚油酸含量,降低棕榈酸含量。当处理和未处理幼苗在5℃低温下生长6d期间,两者的磷脂酰胆碱含量均随低温时间的延长而递减,但处理苗的含量一直高于对照苗的含量。对照苗的亚油酸含量亦随低温时间的延长而递减,处理苗的亚油酸含量则在6d低温期间基本保持稳定,且一直高于对照。对照苗的棕榈酸含量随低温时间延长而递增,处理苗表现为短期低温棕榈酸含量降低,长期低温含量增加,但仍较对照为低,因而处理苗的脂肪酸不饱和度和亚油酸/棕榈酸比值始终高于对照苗。     

不同浓度IAA对微藻TH6（Oedocladium sp．）生长及脂肪酸含量的影响

研究了在BG11液体培养基中添加0.1～1.5 mg·L-1 IAA对微藻TH6(Oedocladium sp. )生长和脂肪酸含量的影响.结果表明,随培养时间的延长,微藻TH6的生长量逐渐增加;与对照相比,添加不同浓度IAA对微藻TH6的生长均有不同程度的促进作用,其中添加1.0 mg·L-1 IAA对微藻TH6生长的促进效果最佳,至培养第33天,微藻TH6的生长量比对照提高了44.34%.在培养基中添加IAA均能不同程度提高微藻TH6的总脂肪酸含量,当IAA 浓度为0.1、0.5、1.0和1.5 mg·L-1时,总脂肪酸含量分别是对照的2.09、2.13、2.41和1.73倍.IAA对微藻TH6中软脂酸、硬脂酸、亚油酸和油酸含量的影响作用不同.添加不同浓度IAA均能不同程度提高软脂酸的含量,当IAA浓度为1.0 mg·L-1时,软脂酸的相对含量最高,达到了28.62%;较高浓度的IAA(1.0和1.5 mg·L-1)能促进硬脂酸含量的提高, 低浓度IAA(0.1和0.5 mg·L-1)使硬脂酸含量降低;当IAA浓度为0.1～1.0 mg·L-1时,亚油酸含量较对照有不同程度提高;IAA对油酸含量的影响作用不明显.研究结果显示,含有1.0 mg·L-1 IAA的BG11液体培养基为微藻TH6的最佳液体培养基.在这一培养基中,微藻TH6的总脂肪酸含量最高,饱和及不饱和脂肪酸含量也较高,且微藻TH6生长量最大,可作为生物柴油资源进一步研究和开发.     

培养条件对钝顶螺旋藻(Sp)NS-90020脂肪酸组成和含量的影响

研究了不同培养条件对钝顶螺旋藻（Sp）NS－90020脂肪酸合成的影响。随着温度升高,其不饱和脂肪酸,γ一亚麻酸（GLA）相对含量降低,总脂肪酸含量升高,当温度为40℃时总脂肪酸和γ-亚麻酸绝对含量都达到最大值,分别为73．4mg／g干重和11．9mg／g干重;当培养基中NaCl浓度高于0．017mol／L时,其GLA相对含量降低,但低于0．0017mol／L时,对其脂肪酸组成无显著影响;氨水使其脂肪酸和GLA绝对含量升高,并在50mgN（NH3·H2O）时达到最大值,分别为67．96mg／g干重和13．63mg／g千重;暗处理92h使其总脂肪酸和GLA绝对含量升高;缺乏Fe2 或Mg2 或Mo2 时,其总脂肪酸和GLA绝对含量降低,而缺乏PO43-时,其总脂肪酸和GLA绝对含量略有升高。     

蜜环菌油超声提取工艺优化及其化学成分分析

研究了料液比、超声时间、超声温度及超声功率对蜜环菌出油率的影响,并通过正交试验确定了提取蜜环菌油最佳工艺。结果表明:最佳提取工艺是料液比(g∶m L)1∶4,时间30 min,温度40℃,功率400 W。应用气相色谱-质谱联用技术研究了野生蜜环菌子实体中油类成分及其相对含量,确认其中9个成分,分别为亚油酸、硬脂酸、软脂酸、羊脂酸、正壬酸、月桂酸、肉豆蒄酸、正十五烷酸和反式棕榈油酸。     

不同加工工艺对真空油炸花生品质特性的影响

探讨了不同加工工艺对真空油炸（VF）花生品质特性的影响,结果表明：与对照相比,浸泡处理使VF花生制品容重显著下降;冷冻处理可以增加制品得率和酥脆度,提高商品性,不造成对制品理化指标的显著影响;蒸煮处理对制品的理化指标均无显著影响;随着真空油炸温度的升高,花生制品的容重、得率、脂肪、油酸呈升高趋势,亚油酸、棕榈酸呈现下降趋势。与原料相比,经浸泡、蒸煮和冷冻处理后,VF花生制品的脂肪、油酸、山梨酸、硬脂酸、花生酸含量显著升高,亚油酸、棕榈酸、组氨酸、脯氨酸含量显著下降,而蛋白质及必需氨基酸等指标变化较小。相关性分析表明,脂肪、蛋白质、油酸、亚油酸、Arg、Leu、容重、得率等理化指标之间呈现显著或极显著相关关系。     

除臭大蒜口服液的GC／MS分析

应用GC/MS联用技术,对除臭大蒜口服液进行了检测,定性鉴定了25种含硫有机化合物。二烯丙基硫醚、甲基烯丙基三硫醚、3-乙烯基-1,2-二硫杂-5-环己烯、2-乙烯基-1,3-二硫杂-5-环己烯和二烯丙基三硫醚是主要组分;二烯丙基四硫醚、烯丙基四硫化氢、2-和3-(2’,3’-二硫杂-5’-己烯基)-3,4-二氢-2H-噻喃、2-(2’-[3’,4’-二氢-2H噻喃基])-1,3-二硫杂-5-环己烯和3-(2’-[3’,4’-二氢-2H-噻喃基])-1,2-二硫杂-5-环己烯是次要组分。最后4种次要组分在大蒜油和大蒜口服液中的鉴定在国内尚属首次。     

Influence of Meteorological Factors on Oil Content and Major Fatty Acids of Rapeseeds (Brassica napus L. )

1IntroductionOilseedrape(BrassicanapusL.)isthemostimportantsourceofedibleoil,andtheYangtzeRiverlowerbasinisthemaincultivationregioninChina.Duringlastdecade,winterrapeproduc-tionisincreasinginthecereal-growingregionsafterthericeharvest(Zhou,1994).Weathervari-ablessuchassolarradiation,temperature,precipitation,windandhumidityhavepronouncedef-fectsonrapegrowth,developmentandseedyield(Almondetal.1986).itisprobablethatahigh-ertemperatureduringvegetativegrowththanatmainfloweringandseedfillingprod…     

The effect of the acidity of rapeseed oil on its transesterification

The aim of this work is to study the transesterification of vegetable oil with a high acid number at unchanged reaction conditions. Rapeseed oil was used as the raw material and its acid number was changed by the addition of oleic acid (from 0.89 to 12.25 mg KOH/g). Methanol was used for transesterification (molar ratio of oil to methanol 1:6) and potassium hydroxide was used as a catalyst. After the reaction time, the residue of the catalyst was neutralised by gaseous carbon dioxide and the methanol excess was removed. After the separation of two phases, each of them was analyzed (in the ester phase: yield, content of methyl ester and acid number; in the glycerol phase: yield, density, viscosity, content of glycerol, soaps, methyl ester, potassium carbonate and hydrogen carbonate). The obtained data was compared with theoretical material balances and the effect on the saponification of oil was discussed. The results show that the yield of methyl ester (biodiesel) is significantly affected by a higher acid number, as well as enhanced soap formation. On the other hand, the conversion of the oil and acid number of the ester phase remain at constant values in studied borders.     

Expression of fungal diacylglycerol acyltransferase2 genes to increase kernel oil in maize

Maize (Zea mays) oil has high value but is only about 4% of the grain by weight. To increase kernel oil content, fungal diacylglycerol acyltransferase2 (DGAT2) genes from Umbelopsis (formerly Mortierella) ramanniana and Neurospora crassa were introduced into maize using an embryo-enhanced promoter. The protein encoded by the N. crassa gene was longer than that of U. ramanniana. It included 353 amino acids that aligned to the U. ramanniana DGAT2A protein and a 243-amino acid sequence at the amino terminus that was unique to the N. crassa DGAT2 protein. Two forms of N. crassa DGAT2 were tested: the predicted full-length protein (L-NcDGAT2) and a shorter form (S-NcDGAT2) that encoded just the sequences that share homology with the U. ramanniana protein. Expression of all three transgenes in maize resulted in small but statistically significant increases in kernel oil. S-NcDGAT2 had the biggest impact on kernel oil, with a 26% (relative) increase in oil in kernels of the best events (inbred). Increases in kernel oil were also obtained in both conventional and high-oil hybrids, and grain yield was not affected by expression of these fungal DGAT2 transgenes.     

USE OF SENSORY EVALUATION FOR MEASURING DEODORIZING EFFECTS OF AN AIR CONDITIONER

The application of sensory methodology for measuring deodorizing effect of an air conditioner equipped with electric plasma was introduced. Deodorizing effect was measured using chemical and sensory methods at different time (0, 30 and 60 min) and mode (control, blowing and cooling) of an air conditioner. Smoke from a roll of cigarette in a closed room was used as a source of odor and the concentrations of acetic acid and ammonia were measured as odorous chemical components. As one of the sensory methods triangle test was used and as a first step to obtain deodorizing effects by triangle test, the threshold of each panelist was obtained as the log dilution ratio of odor concentration at which the difference from odorless air was detected. The odor concentration at each time and mode was calculated using the threshold of the panel and the deodorizing effect was obtained on the basis of the odor concentration. In addition to a triangle test, scaling methods such as category scaling or magnitude estimation were used to measure deodorizing effect of an air conditioner. Deodorizing effects by scaling methods were calculated based on odor intensity with time at each mode. The regression analysis was done between the efficacy of deodorizing effect by sensory test and those by acetic acid and ammonia, the R² values of the regression equations for triangle test, category scale, and magnitude estimation were 0.84, 0.72 and 0.69, respectively. Deodorizing effect by triangle test explained the decrease of acetic acid and ammonia better than those by category scaling or magnitude estimation while high cost and time consuming labor involved in triangle tests reduced the merit. The results of this study demonstrated that various sensory methods could be used to measure deodorizing effect of air conditioners and further researches on fast and reliable methods are needed to establish the official procedures.     

Biodiesel production from high acid value waste frying oil catalyzed by superacid heteropolyacid

Transesterification of waste cooking oil with high acid value and high water contents using heteropolyacid H3PW12O40 x 6H2O (PW12) as catalyst was investigated. The hexahydrate form of PW(12) was found to be the most promising catalyst which exhibited highest ester yield 87% for transesterification of waste cooking oil and ester yield 97% for esterification of long-chain palmitic acid, respectively. The PW12 acid catalyst shows higher activity under the optimized reaction conditions compared with conventional homogeneous catalyst sulfuric acid, and can easily be separated from the products by distillation of the excess methanol and can be reused more times. The most important feature of this catalyst is that the catalytic activity is not affected by the content of free fatty acids (FFAs) and the content of water in the waste cooking oil and the transesterification can occur at a lower temperature (65 degrees C), a lower methanol oil ratio (70:1) and be finished within a shorter time. The results illustrate that PW12 acid is an excellent water-tolerant and environmentally benign acid catalyst for production of biodiesel from waste cooking oil.     

Effect of increasing amounts of dietary fish oil on brain and liver fatty composition

Increasing dietary fish oil in rat had the following effect on brain lipids: Arachidonic acid regularly decreased; eicosapentanenoic acid, normally nearly undetectable, was present; 22:5(n - 3), dramatically increased but remained below 1% of total fatty acids; cervonic acid was increased by 30% at high fish oil concentration. Saturated and monounsaturated fatty acids were not affected regardless of chain-length. In contrast, in the liver, nearly all fatty acids (saturated, monounsaturated and polyunsaturated) were affected by high dietary content of fish oil, but liver function was normal: serum vitamin A and E, glutathione peroxidase, alkaline phosphatase, transaminases were not affected. Serum total cholesterol, unesterified cholesterol and phosphatidylcholine were slightly affected. In contrast, triacylglycerols were dramatically reduced in proportion to the fish oil content of the diet.     

松籽油的干式酶法提取工艺优化与理化性质分析

应用单因素实验设计对干式酶法松籽油提取工艺进行优化。结果表明,干式酶法提取松籽油最佳制备工艺为：0.2%淀粉酶、料液比为6：1、酶解温度为55℃、酶解时间为8 h,所得最大出油率为90.2%,残油率为6.2%。经检测最佳制备条件提取的松籽油不饱和脂肪酸的含量为90.09%,其中油酸含量为26.84%,介酸含量为2.41%、亚油酸含量为46.25%、皮诺敛酸为14.59%;饱和脂肪酸中棕榈酸含量为6.5%、硬脂酸为3.41%。松籽油酸价为2.61 mg·g^-1、过氧化值为1.56 mmol·kg^-1、丙二醛含量为0.41 mg·kg^-1。所有检测结果均高于《中华人民共和国粮食行业标准LS/T 3242-2014》松籽油中质量标准的要求。     

Exogenously applied glycinebetaine enhances seed and seed oil quality of maize (Zea mays L.) under water deficit conditions

A field trial was carried out to appraise up to what extent exogenous application of a potential osmoprotectant, glycinebetaine (GB), could ameliorate the inhibitory effects of shortage of water on maize seed and seed oil composition and oil antioxidant potential. Two maize cultivars, Agaiti-2002 (drought tolerant) and EV-1098 (drought sensitive), were exposed to drought treatments at the vegetative growth stage. Both the maize cultivars used in the present study are being widely cultivated in Pakistan and have been an important source of developing different maize hybrids. Two levels of glycinebetaine (0 or 30 mM) were foliar-applied at the vegetative stage. Water stress reduced the kernel sugar, oil, protein, moisture contents and most of the seed micro- and macro-nutrients analyzed of both maize cultivars, but it increased the contents of seed fiber and ash contents. Among different seed oil un-saturated fatty acids, water stress increased the oil oleic acid contents with a decrease in linoleic acid contents, which resulted in increased oil oleic/linoleic ratio of both maize cultivars. However, no variation was observed in oil stearic and palmitic acid contents due to water stress. A considerable increase in seed oil α-, γ-, δ- and total tocopherols and flavonoids was observed in both maize cultivars. However, oil phenolic content and 1,1′-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging activity decreased. Foliar-applied GB significantly increased the contents of seed sugar, oil, protein, moisture, fiber, ash, GB contents and micro- and macro-nutrients of both maize cultivars under well irrigated and water deficit conditions. Furthermore, exogenous application of GB increased the oil oleic and linoleinic acid contents. All different lipophilic compounds estimated in the seed oil increased due to foliar applied GB. Furthermore, GB also increased seed oil antioxidant activity appraised in terms of oil DPPH free radical scavenging activity. By summarizing the results, it seemed that exogenously applied GB remained in intact form until later stages of growth and counteracted the inhibitory effects of water deficit on seed and seed oil composition similarly of both maize cultivars.