5倍葡萄柚油及葡萄柚油香气成分分析及讨论

运用气相色谱/质谱联用技术,对5倍葡萄柚油及葡萄柚油进行成分分析和鉴定。从5倍葡萄柚油中鉴定出49种化合物,其中萜烯类化合物占全油的90.96%,含氧化合物占全油的6.03%,特征成分圆柚酮相对含量为0.60%;从葡萄柚油中鉴定出23种化合物,其中萜烯类化合物占全油的98.28%,含氧化合物占全油的1.55%,特征成分圆柚酮相对含量为0.05%。比较了5倍葡萄柚油和葡萄柚油之间的差别,并对由此导致的香气差异进行了讨论。     

巴西苦橙精油和苦橙花精油的挥发性成分分析及卷烟应用效果

采用水蒸气蒸馏技术制备巴西苦橙精油和苦橙花精油,并采用GC/MS对2种精油中的挥发性成分进行对比分析,共分析出苦橙精油中的挥发性成分31种,苦橙花精油中的挥发性成分33种,其中共有成分为11种。苦橙精油中的主要挥发性成分为柠檬烯(79.953%)、柠檬烯氧化物(2.371%)、柠檬烯环氧化物(1.695%)、右旋香芹酮(1.014%)、乙酸橙花酯(1.266%)、顺式-香芹醇(1.324%)、香叶酸(1.131%)等。苦橙花精油中的主要挥发性成分为β-蒎烯(12.056%)、柠檬烯(12.252%)、罗勒烯(4.8%)、芳樟醇(32.386%)、乙酸芳樟酯(3.307%)、α-松油醇(5.219%)、乙酸橙花酯(3.801%)、乙酸香叶酯(3.403%)、香叶醇(2.252%)、橙花叔醇(5.365%)、金合欢醇(3.548%)。将两种精油进行卷烟感官评价,结果显示,不同的挥发性组分形成了香韵及效果的差异。苦橙花精油在卷烟中主要赋予卷烟清新柑橘类果香,并带有花香底韵,具有改善卷烟吃味和余味等效果;苦橙花精油在卷烟中主要赋予卷烟醇甜花香,带有果香底韵,并具有丰富烟香和细腻烟气等效果。     

从葡萄皮红中分离纯化锦葵花素葡萄糖苷的研究

利用柱层析和重结晶方法对葡萄皮红中锦葵花素葡萄糖苷的分离纯化工艺进行了研究。结果表明,Amberlite XAD-16大孔树脂柱层析、活性炭/硅藻土混合柱层析和聚酰胺柱层析的最佳洗脱浓度分别为20%乙醇水溶液、15%甲醇-氯仿和30%乙醇水溶液。将产品按固液比为1∶5(m/v)的比例加入甲醇溶解,再加入20 mL正丁酮,冷冻36 h,得到的单体含量可达95%。该工艺成本低廉,原料来源广泛,产品纯度高,具有广阔的应用前景。     

大孔树脂吸附分离酶解法苦楝素提取液的研究

研究了大孔树脂吸附分离酶解法苦楝素提取液的工艺条件及参数,LS-100型大孔吸附树脂明显优于AB-8型和NAK-Ⅱ型,其吸附分离苦楝素的吸附优化条件为:溶液pH值7.0,吸附温度45℃,平衡吸附时间4 h;解吸优化条件为:解吸剂为80%乙醇-水溶液,pH值5.0,解吸操作温度35℃,时间2.5 h。在此优化条件下,苦楝素的饱和吸附量可达201.6 mg/g,解吸率达88.9%。     

生姜精油、浸膏和油树脂的提取及成分分析

为比较不同方法提取姜油的得率和成分差异,用气质谱联用技术对水蒸气蒸馏、乙醇浸提和超临界CO2萃取所得姜油进行了比较分析。结果表明,不同方法的姜油得率和化学成分差异较大:姜油得率依次为超临界CO2萃取法(4.67%)、乙醇浸提法(3.75%)和水蒸气蒸馏法(0.95%)。从水蒸气蒸馏所得精油中鉴定出68种成分,主要是呈现芳香性气味的倍半萜类化合物(相对质量分数,下同,63.46%)和单萜类化合物(34.91%);从乙醇浸提所得浸膏中鉴定出41种成分,主要是呈现辛辣味的姜辣素类化合物(86.41%),其中主要为6-姜酚(16.86%)、6-姜烯酚(16.58%)、姜油酮(17.68%);从超临界CO2萃取所得油树脂中鉴定出77种成分,挥发性的萜类化合物和非挥发性的姜辣素类化合物分别占总质量的59.31%和40.69%,具有浓郁的芳香气味和强烈的辛辣味。     

AB8大孔吸附树脂分离姜油树脂中的姜酚

针对溶剂萃取法获得的姜油树脂,用AB8大孔吸附树脂作为分离载体,乙醚和正己烷作为洗脱剂体系分离姜油树脂中的有效成分姜酚。用GC-MS对实验样品进行了表征,用峰面积归一化法确定了各组分的峰面积百分数,与姜酚标准样品对照,确定了姜酚的富集率。结果表明,当选用乙醚和正己烷组成洗脱剂体系时,经分离后的样品中成分种类减少,由姜油树脂中的7大类物质27种成分,减少到分离后的3大类物质11种成分;姜油树脂中占相当比例的烯类物质峰面积百分数明显下降,姜酚的峰面积百分数由姜油树脂原样中的1.27%提高到55.68%,分离效果明显,富集率达70.88%。     

高纯度金丝桃素生产工艺研究

利用大孔吸附树脂吸附法研究了金丝桃素的提取分离方法.结果表明,采用HZ 816大孔吸附树脂对贯叶连翘粗提物进行吸附纯化,以水、40%乙醇、60%乙醇洗去大量杂质后,以80%乙醇解吸,所得样品再经酸水结晶可得高纯度的金丝桃素.该方法简便,消耗低,产品纯度高,回收率高.     

大孔树脂对贯叶连翘中金丝桃素的静态吸附

考察了18种不同类型的大孔树脂对贯叶连翘中金丝桃素的静态吸附和解吸效果,并对3种效果较好的树脂进行了吸附动力学研究;比较了上样液pH对吸附效果的影响;探讨了NKA-9树脂在25℃等温吸附过程,并应用Langmuir方程进行了拟合。结果表明,弱极性树脂NKA-9对金丝桃素吸附解吸作用最好,到达吸附平衡时间为1h左右,吸附量可达12.45mg/g干树脂。上样液最佳pH=4,上样液pH对树脂的吸附有很大影响。NKA-9树脂对金丝桃素的吸附为单分子吸附,符合Langmuir吸附理论。     

薰衣草精油的提取及成分鉴定

本文采用改进的水蒸气蒸馏从薰衣草全草中提取精油,经气相色谱—质谱联用(GC-MS)分离鉴定了精油的化学成分,共分离出58个组分,鉴定了芳樟醇(26.59%)、薰衣草醇(5.44%)、乙酸芳樟酯(23.01%)、乙酸薰衣草酯(10.80%)等42种化合物,占总出峰面积的96.48%。实验结果表明,采用改进的水蒸气蒸馏,不仅可以降低能耗,还能提高精油的品质。     

大孔吸附树脂吸附乳酸及乳酸与谷氨酸的分离

通过筛选,得到大孔吸附树脂NKA-II,并用其对乳酸进行分离. 测定了该树脂对乳酸与谷氨酸的吸附选择系数,得到了乳酸在NKA-II上的吸附等温线,并对其吸附动力学和动态吸附进行了研究. 结果表明,NKA-II对乳酸和谷氨酸的吸附选择系数KGL=16.19. 该树脂对乳酸的吸附等温线符合Freundlich方程,在26和48℃下的相关系数R2均大于0.99,方程的特征参数n>1,属"优惠吸附". 吸附动力学研究表明,粒内扩散是吸附过程的主要控制步骤,符合Kannan-Sundaram粒内扩散模型,相关系数R2=0.9906,粒内扩散速率常数kp=6.0129 mg×min0.5/g. 动态吸附实验结果表明,乳酸的穿透体积比谷氨酸大110.6 mL,故该树脂可以成功地应用于乳酸与谷氨酸的分离.     

柚皮活性炭对氨氮吸附性能研究

采用氯化锌活化法制备柚皮活性炭,探讨其对废水中氨氮的吸附性能。结果表明,在pH为2～12,温度为30～50℃条件下,柚皮活性炭对氨氮均能取得较好的吸附效果;相同氨氮初始浓度条件下,随着投加量增加,单位质量柚皮活性炭对氨氮的吸附量明显减少;初始氨氮浓度越大,氨氮吸附量也越大。吸附数值遵循Henry及Freundlich等温吸附模型,吸附过程符合准二级动力学方程。     

大孔树脂分离纯化核桃青皮总黄酮的研究

以总黄酮回收率为考察指标,研究了大孔树脂分离纯化核桃青皮总黄酮的工艺。结果表明:D101型树脂对核桃青皮总黄酮有较好的吸附分离性能,是分离纯化核桃青皮总黄酮的适宜大孔树脂;最佳工艺条件为:上柱总黄酮与干树脂质量比为1:12,上样液质量浓度可在3.0875～6.175 g/L 范围内,pH值为5, 6BV(1BV=23.7 mL)的水洗后用5BV的70%乙醇洗脱。经D101处理后的核桃青皮总黄酮回收率在60%,纯度可达80%以上。该工艺简便,能有效分离纯化核桃青皮黄酮类化合物。     

Separation of fatty acid methyl esters from tall oil by selective adsorption

Fatty acid methyl esters (FAME) and resin acids (RA) were separated from tall oil by selective adsorption. Commercial nonmodified molecular sieve 13X was used as adsorbent. The adsorption isotherms of fatty acids (FA), FAME, and RA on molecular sieve 13X at 25°C were determined using various solvents. The solvents were methanol, ethanol, isopropanol, acetone, benzene, hexane, isooctane, petroleum ether (40–60°C), and petroleum naphtha (80–180°C). With each solvent, FA and RA were adsorbed to a greater extent than FAME. Adsorption isotherms for RA and FAME in binary adsorption systems were also determined using petroleum ether, petroleum naphtha, benzene, and isopropanol. For each component in the binary adsorption, the equilibrium amounts are lower than the values for pure component adsorption. The adsorption of FAME decreased in the presence of RA markedly in petroleum ether and petroleum naphtha. This fact may be the indication of the phenomenon of selective adsorption. Separation was accomplished by adding a solution of esterified tall oil in solvents used in the binary adsorption systems, through a column packed with molecular sieve 13X. With petroleum naphtha, FAME and RA were recovered in yields of 93 and 94%, respectively, from esterified tall oil. Petroleum naphtha gave the best results. The effects of particle size of adsorbent and flow rate of solvent on the efficiency of the separation were also investigated in fixed-bed column studies. The particle size of adsorbent did not apparently alter the results. Changes in the particle size should not significantly change the number of available adsorption sites in a microporous molecular sieve.     

Mechanistic elucidation and evaluation of biosorption of metal ions by grapefruit peel using FTIR spectroscopy,kinetics and isotherms modeling,cations displacement and EDX analysis

BACKGROUND: The performance and mechanism of the biosorptive removal of Ni²⁺ and Zn²⁺ from aqueous solution using grapefruit peel (GFP) as a new biosorbent was investigated by using different experimental approaches, such as potentiometric titration, Fourier transform infrared (FTIR) and energy‐dispersive X‐ray spectroscopy (EDX) analysis, chemical blocking of functional groups and concomitant release of cations (Ca²⁺, Mg²⁺, Na⁺, K⁺) from GFP with metal (Ni²⁺, Zn²⁺) uptake. RESULTS: GFP removed Ni²⁺ and Zn²⁺ rapidly, with 84.73% and 92.46% of the equilibrium sorption being reached in 30 min for Ni²⁺ and Zn²⁺, respectively. The equilibrium process was described well by the Langmuir isotherm model, with maximum sorption capacity of 1.33 and 1.51 meq g^?1 for Ni²⁺ and Zn²⁺, respectively. Release of cations (Ca²⁺, Mg²⁺, Na⁺, K⁺) and protons H⁺ from GFP during uptake of Ni²⁺ and Zn²⁺ and EDX analysis of GFP before and after metal sorption revealed that the main mechanism of sorption was ion exchange. FTIR spectroscopy showed that carboxyl and hydroxyl groups were involved in the sorption of Ni²⁺ and Zn²⁺. Blocking of these groups revealed that carboxylic group was responsible for 78.57% and 73.31% of Ni²⁺ and Zn²⁺ removal, respectively whereas 22.63% and 28.54% was due to the hydroxyl group. The GFP could be regenerated using 0.1 mol L^?1 HCl, with more than 98% metal recovery and reused for five cycles without any significant loss in its initial sorption capacity. CONCLUSIONS: The study suggests that GFP has promising potential for use as an efficient and cost‐effective biosorbent for the removal and recovery of Ni²⁺ and Zn²⁺ from aqueous solution. Copyright © 2009 Society of Chemical Industry     

从沙田柚皮中提取精油的工艺研究

为了综合利用沙田柚皮，进行了从沙田柚果皮提取精油的研究，通过实验筛选，得到了柚皮精油提取的最佳工艺条件：采用石油醚为提取溶剂，m(石油醚)：m(柚皮)=24：1，回流提取两次，每次提取60min。提取液进行真空浓缩，得精油粗产品。往精油粗产晶中加入乙醇溶解．放入-5℃冰箱中冷冻过夜，抽滤，滤液进行真空浓缩，即得精油，产率约1．96％。φ(精油)=99．2％。实验得到的柚皮精油为独特柚子香味的黄色油状液体，难溶于水，易溶于乙醇等有机溶剂，物理参数为：相对密度d20^20=0．857，旋光度为a= 97。折光率n=14765.     

大孔树脂吸附分离丹参提取液中丹酚酸B的工艺研究

对国内几种大孔吸附树脂的丹酚酸B吸附性能进行了实验筛选。结果表明。YWD06树脂有较好的吸附和洗脱能力;适宜吸附条件：pH值控制在4-5、流速为2BV/h;以70%乙醇为洗脱剂,pH值=5、流速为3BV/h时,洗脱效果好。     

大孔树脂吸附分离丹参提取液中丹酚酸B的工艺研究

对国内几种大孔吸附树脂的丹酚酸B吸附性能进行了实验筛选。结果表明。YWD06树脂有较好的吸附和洗脱能力;适宜吸附条件:pH控制在4～5、流速为2BV/h;以70%乙醇为洗脱剂,pH=5、流速为3BV/h时,洗脱效果好。     

Deterpenation of Brazilian orange peel oil by vacuum distillation

The deterpenation of orange peel oil in most industries is accomplished by vacuum distillation, but surprisingly little information on this matter can be found in the open literature. This work reports recent results on orange peel oil deterpenation carried out in an automatic vacuum distillation column operated in the semibatch mode at the temperatures of 50, 65, and 80°C, at 10, 20, and 30 mbar, and with reflux ratios of 0.25, 0.50, and 0.75. The concentrates were analyzed with regard to the oxygenate compound content by gas chromatography coupled with a mass spectrometer (GC-MS) and evaluated by sensory analysis, and also with regard to the aldehyde content. As one could expect, there is a strong relationship between oil quality, as revealed by the sensory analysis, and chemical composition, as determined by GC-MS. The concentration factor and process yield, as expressed by “fold,” together with the analysis results show that it is possible to obtain high quality concentrates simply by manipulating the operating variables in the vacuum fractionation process.     

Separation of palm carotene from crude palm oil by adsorption chromatography with a synthetic polymer adsorbent

Palm carotene was successfully concentrated from crude palm oil by a single-stage chromatographic process on a synthetic porous polymer. Carotene was concentrated to about 10⁵ ppm solution, which is about 160 times the original concentration in crude palm oil. Carotene recovery varied from 40 to 65% depending upon chromatographic conditions. The fatty acid composition of the palm oil did not change during the carotene recovery process, and the carotene composition was also almost the same as that in palm oil. Adsorption isotherms of the adsorbent differed from other adsorbents. This new recovery method for palm carotene may be suitable as an edible palm oil pretreatment process due to its efficient mass recovery of a valuable bioresource.