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1.
超临界CO2萃取鱼腥草的挥发油成分   总被引:12,自引:2,他引:10  
从萃取的压力、温度、流量和时间等条件探讨超临界CO2萃取对鱼腥草(Houttuynia cordata Thunb.)挥发油萃取率的影响,确定最佳萃取条件为萃取压力20mPa、温度35℃、CO2流量40kg/h和萃取时间80min,鱼腥草挥发油得率为1.76%。而水蒸气蒸馏提取和石油醚提取的得率分别为0.05%和0.08%。超临界CO2法萃取的鱼腥草挥发油收率高,萃取时间短。  相似文献   

2.
采用索氏法、超临界CO2 萃取法、酸热法和有机溶剂法分别提取雅致枝霉、拉曼被孢霉、少根根霉、畸雌腐霉和橙黄红酵母的油脂 ,从样品要求、最小样品量、仪器要求、处理样品能力及油脂得率等方面对 4种提取方法进行综合评价 ,并对索氏法、超临界CO2萃取法和酸热法提取的雅致枝霉油脂的脂肪酸组成进行气相色谱分析。索氏法的油脂得率最高 ,但耗时较长 ;超临界CO2 萃取法和酸热法的油脂得率相近 ,较索氏法略低 ,但酸热法更为简便 ,单位时间内样品处理能力  相似文献   

3.
四种真菌油脂提取方法的比较研究   总被引:45,自引:0,他引:45  
采用索氏法、超临界CO2萃取法、酸热法和有机溶剂法分别提取雅致枝霉、拉曼被孢霉、少根根霉、畸雌腐霉和橙黄红酵母的油脂,从样品要求、最小样品量、仪器要求、处理样品能力及油脂得率等方面对4种提取方法进行综合评价,并对索氏法、超临界CO2萃取法和酸热法提取的雅致枝霉油脂的脂肪酸组成进行气相色谱分析。索氏法的油脂得率最高,但耗时较长;超临界CO2萃取法和酸热法的油脂得率相近,较索氏法略低,但酸热法更为简便,单位时间内样品处理能力强;有机溶剂法提取效果最差。我们建立的酸热法是一种适合油脂及多水饱和脂肪酸高产菌株筛选的简便、有效的真菌油脂提取方法。  相似文献   

4.
生姜的超临界CO2提取分离工艺的研究   总被引:1,自引:0,他引:1  
本文研究了超临界CO2流体萃取生姜的工艺,探讨了萃取压力、温度扣时问等因素对生姜萃取率的影响,通过正交实验确定了生姜超临界CO2流体萃取最佳工艺:生姜原料切成薄片,含水率15%以下,萃取条件为压力24Mpa、温度40℃、时间2h。  相似文献   

5.
采用正交实验设计,对肾叶天胡荽(Hydrocotyle wigordi Maxim.)精油超临界CO2萃取条件进行了优化,并用GC—MS分析技术对精油的化学成分进行了鉴定,初步探讨了肾叶天胡荽精油对小菜蛾2龄幼虫的触杀活性。结果表明,肾叶天胡荽精油超临界CO2萃取的最佳条件为萃取压力35MPa、萃取温度50℃、解析压力5MPa、解析温度40℃、萃取时间75min、CO2流量34—36L·h^-1,精油得率最高可达5.32%。从精油中共鉴定出19种成分,总相对含量达到89.266%,主要成分为邻苯二甲酸二辛酯(64.302%)。用超临界CO2萃取技术提取的肾叶天胡荽精油对小菜蛾2龄幼虫有一定的触杀作用,20g·L^-1精油对小菜蛾2龄幼虫的24h校正死亡率高达90.00%。  相似文献   

6.
本实验采用超临界CO2萃取技术从冻干洋葱粉中萃取挥发油。以洋葱挥发油得率为考察指标,经单因素及正交试验,考察了萃取温度、萃取压力、CO2流量、萃取时间4个因素对超临界CO2流体萃取的影响。结果表明萃取压力20 MPa,萃取温度35℃,CO2流量为14 kg/h的条件下萃取2.5 h为最佳工艺,洋葱挥发油得率达0.53%。  相似文献   

7.
超临界二氧化碳萃取鸢尾油的工艺条件研究   总被引:1,自引:0,他引:1  
本文采用L9(3^4)正交实验考察了二氧化碳超临界萃取中萃取压力、萃取温度和萃取时间对鸢尾精油提取率的影响。结果表明各影响因子的影响顺序为:压力〉时间〉温度;当原料的颗粒度为60-80目、CO2流量为20.0m^3/h时,用超临界二氧化碳萃取鸢尾精油的最佳工艺条件为:萃取压力26.0MPa,萃取温度55.0℃,萃取完成时间为2.5h,此条件下鸢尾香根中鸢尾油的萃取率高达12.71%,得到的精油中鸢尾酮的含量为39.95%,与索氏法和微波提取法相比,超临界萃取具有提取率高和产品质量好的优点。  相似文献   

8.
超临界CO2萃取技术应用于花椒油树脂分离工艺的研究   总被引:5,自引:0,他引:5  
本文研究了超临界迷萃取花椒油树脂的工艺,探讨了萃取压力、温度和时间等因素对花椒萃取率的影响,通过正交实验法确定了花椒超临界迷流体萃取的最佳工艺:花椒原料粒度为60日,萃取条件为压力32Mpa、温度55℃、时间1h。  相似文献   

9.
本文通过超临界CO2提取芝麻油的均匀设计实验和微波和超声波诱导提取芝麻油的正交实验比较,考察影响提取的主要因素,寻求最佳萃取工艺。超临界CO2萃取最佳工艺条件为:压力32MPa,温度60℃,CO2流量31kg/h,萃取时问80min,得率46.39%;微波萃取最佳工艺条件为:溶剂为丙酮,物料与溶剂比例1:7,辐射时间7min,辐射功率810W,得率23.01%。超声波萃取最佳工艺条件为:物料与溶剂比例1:7,溶剂为石油醚,浸泡时间30h,得率23.99%。结果表明超临界CO2萃取芝麻油品质最好,而且萃取也最高,质量最稳定。  相似文献   

10.
应用超临界CO2萃取技术,从三孢布拉霉菌提取β-胡萝卜素后产生的结晶脚料中去除脂溶性杂质成分,以回收β-胡萝卜素.考察了萃取过程中温度(25 ℃~55 ℃)、压力(15 MPa~45 MPa)、时间(1.5 h~4.5h)对β-胡萝卜素的回收得率及产品含量的影响.结果表明,在萃取温度35 ℃、压力15 MPa、萃取时间...  相似文献   

11.
利用超临界CO2萃取微孔草籽油,并对籽油进行了HPLC/MS分析。实验确定的最佳超临界CO2流体萃取条件是:萃取温度45℃,萃取压力20MPa,CO2流量为35-40kg/h,萃取时间120min,在此条件下白刺籽油的萃取率为16.12%。利用HPLC/MS对微孔草籽油分析,发现其不饱和脂肪酸的相对含量高达73.19%。比较了超临界CO2萃取微孔草籽油油样和石油醚萃取微孔草籽油油样的理化性质,发现超临界CO2流体萃取的籽油质量优于传统溶剂萃取的籽油。  相似文献   

12.
A study was conducted to determine the transfer of eicosapentaenoic acid (EPA, 20:5) and docosahexaenoic acid (DHA, 22:6) from fish oil into goats’ milk. Goats were sequentially offered three diets: control (C) pellets (lucerne hay-oat grain: 60/40 w/w), C plus tuna oil protected against ruminal biohydrogenation (PTO pellets), and C plus unprotected tuna oil (UTO pellets). In supplemented diets, tuna oil constituted 3% of total dry matter (DM), and each supplement was fed for 7 days, with 12 days allowed between the two fish oil feeding periods to minimise carry-over effects. Dry matter intake, milk yield, protein and fat yield were reduced by feeding UTO, but not PTO, pellets. Goats produced ω-3 enriched milk (0.3–0.5% EPA and 1.01–1.12% DHA) when fed either supplement. The rate of transfer of dietary EPA and DHA to milk ranged from 3.5 to 7.6%. Significant transfer of EPA and DHA from tuna oil into goat milk, without deleterious effects on intake or milk yield is possible, provided that the oil supplement is substantially protected against ruminal biohydrogenation.  相似文献   

13.
Three phenolic compounds-salicylic, caffeic and tannic acids (mono, di and polyphenolic compounds, respectively), were sprayed at two stages (anthesis and pod filling) in two doses. Best results were obtained in response to tannic acid spray @ 100 ppm; groundnut pod yield being 47 Qha-1 and 100 kernels weight 68.7 g. This dose significantly improved oil content (2.7%), oil yield (43.8%) and protein content (5.2%). Maximum linoleic acid (23.4%) was obtained with salicylic acid (40 + 40 ppm) spray, while tannic acid spray @ 100 ppm gave 63.7% oleic acid and 2.8% arachidic acid. However, there was no significant effect on the saturated fatty acids. O/L ratio to the tune 3 was obtained as a result of this treatment thus enhancing the keeping quality of the oil.  相似文献   

14.
以红松籽仁为原料,以无水乙醇为提取溶剂,优化高速匀质-微波辅助提取红松籽油的工艺,考察了匀质速度、匀质时间、液料比、微波温度、微波功率及微波时间对红松籽油提取率的影响,最终确定了红松籽油最佳提取条件为:匀质速度12 000 r·min-1,匀质时间120 s,液料比20 mL·g-1,微波温度60℃,微波功率700 W,微波时间50 min。在上述条件下,红松籽油最优提取率可达60.3%。利用GC-MS对得到的红松籽油的脂肪酸成分进行了分析,其主要成分为棕榈酸、皮诺敛酸、亚油酸、反-13-十八碳烯酸、顺-13-十八碳烯酸、硬脂酸,不饱和脂肪酸含量高达85.55%,其中松籽油所含有的特异性不饱和脂肪酸-皮诺敛酸含量可达13.65%。此外,对该工艺提取得到的红松籽油的抗氧化活性及理化性质进行了评估,发现红松籽油清除DPPH自由基能力强,其IC50值为0.095 4 g·mL-1。此外,红松籽油过氧化值和酸值较低,碘值较高,表明红松籽油是一种品质优良的天然油脂。  相似文献   

15.
A simple and rapid method is described for the preparation of a marine oil fraction highly enriched in (n - 3) polyunsaturated fatty acids. Cod roe, containing lipid up to 15% of its dry weight, approximately 70% of which is phospholipid, was the starting material. Incubation of a concentrated aqueous extract of the roe with porcine pancreatic phospholipase A2 (EC 3.1.1.4) was the key step in the procedure. Extraction of the freeze-dried reaction product with diethyl ether containing formic acid produced an oil in a yield of 1.0 g/100 g wet wt of starting roe. The oil contained over 95% as free fatty acids, with 20:5 (n - 3) and 22:6 (n - 3) accounting for up to 24 and 40%, respectively, of the total free fatty acids. The therapeutic use of the oil is mentioned.  相似文献   

16.
微水体系中荧光假单胞菌脂肪酶催化合成单甘酯   总被引:4,自引:0,他引:4  
研究了无溶剂微水体系中荧光假单胞菌脂肪酶 (PFL)催化油脂甘油解合成单甘酯的反应因素以及多温程非均相固液反应对单甘酯产率的影响。以初始体系最低共熔点 (PFL)取代临界温度学说中的油脂初熔点 ,通过考察不同IEP体系的甘油解 ,发现PFL酶促油脂甘油解时存在碳链基质特异性的函数关系 ,即反应物油脂中饱和碳残基的质量百分含量 (C16+C18)与单甘酯产率间符合以下多项式:Y =- 0.0006X3 +0.0592X2-0.8909X+26.753(13%<X<76.5%),式中X为C16+C18,Y为40℃时等温反应条件下的单甘酯产率。IEP为40℃时,最适等温反应条件如下:加水量3%~4.5%,加酶量为500μ/g油酯摩尔比1:2.5-5.0(油酯:甘油)反应温度40℃.实验条件下多步等程序降温反应48h后单甘酯最高产率为81.4%.  相似文献   

17.
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.  相似文献   

18.
产二十二碳六烯酸等多不饱和脂肪酸真菌的筛选*   总被引:2,自引:0,他引:2  
从土壤中筛选出一株产二十二碳六烯酸(DHA)的丝状真菌,菌丝含油21.23%,DHA占总脂肪酸2.51%;同时含二十碳五烯酸(EPA),占总脂肪酸的0.41%;不饱和脂肪酸占总脂肪酸的80%。经鉴定为头孢霉属(Caphalosporiumsp.)真菌。同时发现两株菌含EPA,经鉴定为小克银汉霉(Cunninghamellasp.)和毛霉(Mucorsp.)。在这几个属中发现DHA和EPA尚属首次。头孢霉菌DHA产量及百分含量和斜面菌种在不同温度下储藏有关。菌种在20℃储藏10天,在液体PDA培养基上发酵,DHA可占总脂肪酸11.27%,产量达63.35mg/L。  相似文献   

19.
本文以氯仿、石油醚和正己烷-异丙醇(3:2,v/v)三种不同溶剂对千年桐种子油进行提取,比较了不同溶剂对种子出油率的影响,结果表明以氯仿为溶剂时出油率最高,达到了35%;并考查了提取时间和提取溶剂体积对出油率的影响.最终优化的提取工艺为:以氯仿为溶剂,液料比为12:1(v/w),提取时间6h,出油率达到了37%.提取的种子油经转酯化后,GC-MS分析其主要脂肪酸组分,结果表明千年桐种子油中总脂肪酸占总油酯的90.55%,其中棕榈酸3.87%,硬脂酸4.11%,亚油酸12.15%,油酸13.31%,亚麻酸12.09%,共轭亚麻酸51.20%和EPA(二十碳五烯酸)3.30%.千年桐种子油中富含不饱和脂肪酸,是一种良好的干性油.  相似文献   

20.
对粘性丝胞酵母进行紫外诱变,获得一株产油率较高的菌株,较原菌株提高了1.53倍。将该菌株接种于用1%硫酸和酶水解处理并浓缩至还原糖浓度为5%的玉米秸秆水解液中培养,生长较好。通过四因素三水平正交实验,确定培养条件为初始pH值7.0、接种量1%、发酵温度30℃、发酵时间5 d时产油率最高。对最佳产油条件进行验证,测得油脂含量为21.3%。从而为利用农业废弃物大规模生产微生物油脂提供了试验数据。气相色谱-质谱联用分析仪显示油脂脂肪酸组成为棕榈酸28.36%,油酸55.86%,10-十八烯酸9.23%,硬脂酸6.70%,可以作为原料生产生物柴油。  相似文献   

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