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1.
本文研究了超临界CO2萃取法的不同提取条件对棘托竹荪中活性物质的抑菌效果影响。通过L16(43)正交实验,选取萃取压力、萃取温度与萃取时间为主要影响因素,采用超临界CO2萃取法,以活性物质对单增李斯特菌和副溶血性弧菌的最小抑菌浓度(MIC)与抑菌率作为提取效果指标,设计棘托竹荪抑菌活性物质的最佳提取条件。由不同提取条件对两种菌抑菌效果的影响程度与显著性分析得出:萃取时间萃取温度萃取压力。棘托竹荪活性物质提取的最佳条件为:萃取压力为20 MPa,萃取温度35℃,萃取时间120 min,所得活性物质对单增李斯特菌与副溶血性弧菌的MIC均为15.0 mg/m L。当抑菌活性物质浓度为MIC时,处理24 h后其对单增李斯特菌与副溶血性弧菌的最佳抑制率分别为85.7%与98.2%。  相似文献   

2.
超临界CO2萃取百合花挥发油的工艺研究   总被引:2,自引:0,他引:2  
本文介绍了超临界CO2萃取百合花中挥发油的提取分离工艺,重点研究了超临界CO2萃取压力、温度、时间对出油率的影响。正交试验结果表明:影响超临界CO2萃取的主要因素为C3〉A2〉B2(A为萃取压力,B为萃取温度,C为萃取时间);最佳工艺参数:SC-CO2萃取压力为18MPa,温度为50℃,时间为90min,流量为25L/min,所得百合花挥发油的出油率高达2.92%。  相似文献   

3.
超临界CO_2流体萃取苦瓜总黄酮工艺及其抗氧化活性   总被引:1,自引:0,他引:1  
利用响应面法优化超临界CO2萃取苦瓜总黄酮的工艺参数,在单因素实验基础上,以萃取时间、萃取温度及萃取压力为自变量,总黄酮提取率为响应值,采用中心组合设计的方法,研究各自变量及其交互作用对总黄酮提取率的影响。结果表明,3个因素对总黄酮提取率的影响大小依次为萃取压力、萃取温度、萃取时间。利用SAS软件和响应面分析相结合的方法模拟得到二次多项式回归方程的预测模型,确定最佳工艺条件:采用无水乙醇为夹带剂(4.0 mL/g),萃取压力33.4 MPa、萃取温度46℃、萃取时间53.2 m in。此条件下,苦瓜总黄酮提取率达到84.3%。抗氧化实验表明:超临界CO2萃取能较好保留苦瓜总黄酮的抗氧化活性,采用超临界CO2萃取法提取的苦瓜总黄酮具有较强的抗氧化活性,当质量浓度为1 mg/mL时,对DPPH自由基的清除能力与Vc相当,清除率达到93.1%。  相似文献   

4.
对采用超临界二氧化碳技术萃取亚麻籽油进行较为系统的研究.选择萃取压力、萃取温度、萃取时间、分离压力4个主要影响因素,运用多因素多水平可视化设计法(m2VD)安排试验.选择分离釜1中产物的质量为试验指标,用自主提出的多因素多水平试验结果可视化分析方法(m2VA)对多维空间试验数据进行分析.得出最佳工艺范围为萃取压力20~ 30 MPa、萃取温度30~46℃、萃取时间77~90 min、分离压力4.0 ~4.7和5.7~5.9 MPa.根据优化工艺范围,在萃取压力为25 MPa、萃取温度40℃、萃取时间83 min、分离压力4.3 MPa下重新试验得到22.87%的得率,对应于质量为34.3 g.  相似文献   

5.
超临界CO2提取甘草地上部分总黄酮   总被引:5,自引:0,他引:5  
采用单因素试验对甘草地上部分(茎叶)的超临界CO2提取工艺进行了研究。实验考察了压力、萃取时间、温度及CO2流量对甘草地上部分总黄酮提取率的影响,以总黄酮提取率和含量为指标,系统的研究了超临界二氧化碳萃取法提取甘草地上部分总黄酮的提取效果。得出的最佳工艺参数为:采用40-60目原料,80%乙醇为夹带剂,萃取时间:1.5 h;萃取压力:30.0 MPa;萃取温度:50℃;CO2流量:10 kg.h-1;分离压力:5.8 MPa;分离温度:40℃。实验结果表明超临界二氧化碳萃取甘草总黄酮的提取率2.09%,含量5.42%,工艺具有提取率高,纯度高的特点,为规模化生产甘草总黄酮的提取提供了研究基础。  相似文献   

6.
采用超临界CO_2萃取菠萝蜜种子中的多酚。通过单因素和正交试验考察了萃取压力、CO_2流量、萃取温度、乙醇浓度、乙醇用量等因素对超临界CO_2萃取菠萝蜜种子多酚产量的影响。实验结果表明各因素对产量影响的大小顺序为CO_2流量萃取温度乙醇浓度乙醇用量萃取压力;最佳萃取工艺条件为:萃取压力175 bar、乙醇浓度70%、乙醇用量5 mL/g、萃取温度50℃、CO_2流量30 g/min、萃取时间1.5 h,在此条件下菠萝蜜种子多酚产量达0.6254 mg/g。  相似文献   

7.
薄荷油超临界CO2萃取条件的优化和筛选   总被引:6,自引:2,他引:4  
以样品中的薄荷脑含量为指标,通过单因素和正交实验对影响薄荷(Mentha haplocalyx Briq.)油超临界CO2萃取的因素进行研究,筛选出薄荷油超临界CO2萃取的最佳条件.研究结果表明,影响样品中薄荷脑萃取率的因素从大到小依次为萃取压力、萃取温度、萃取时间、CO2流量.样品中薄荷脑含量最高的超临界CO2萃取条件为萃取压力10 MPa、萃取温度50℃、CO2流量30 L·h-1且萃取时间1.5 h.  相似文献   

8.
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   

9.
采用正交试验法优化CO2超临界提取葛渣中葛根素的工艺研究。在单因素试验的基础上,选择萃取投料量、萃取温度、萃取压力、萃取时间四个因素,进行L9(34)正交试验设计,评估了这些因素对葛根素提取率的影响。实验结果表明最佳工艺参数为投料量50 g,萃取温度55℃,萃取压力16 MPa,萃取时间90 min。在此条件下,葛渣中葛根素的萃取率为82.5%。  相似文献   

10.
对胡芦巴Trigonella foenum-graecum L.中杀虫活性成分进行超临界CO2萃取分离,并以主要储粮害虫谷蠹Rhyzopertha dominica Fabricius为对象,对其触杀活性进行研究。采用正交试验设计,以萃取液中活性成分的得率、毒力为考察指标,对杀虫活性成分的提取条件进行优化。结果表明:最佳萃取工艺为萃取压力25 MPa,萃取温度55℃,夹带剂为95%乙醇,固液比为200 g:30 mL。萃取压力和夹带剂体积对试验指标有非常显著的影响,萃取温度和夹带剂浓度的影响较小。优化后的萃取方案可达到5.96%的得率。萃取产物对谷蠹的触杀试验结果显示,优化后的超临界CO2萃取工艺对胡芦巴中的杀虫物质具有良好的选择性,得到的萃取物对谷蠹处理10天后的致死中浓度为65.03 μg/cm2,触杀活性明显增加。  相似文献   

11.
A method for the extraction of the alkaloids colchicine, 3-demethylcolchicine and colchicoside from seeds of Colchicum autumnale by supercritical carbon dioxide has been established. Several parameters such as pressure, temperature, percentage of modifier and extraction time have been examined. Two extraction steps with constant carbon dioxide density (0.90 g/mL) and flux (1.5 mL/min) were required to extract the alkaloids in 110 min using 3% methanol as modifier. The quantitative determination of the alkaloids was performed by HPLC; the percentages of recovery were higher than 98% for the three alkaloids. This extraction procedure was compared with a conventional method involving maceration and sonication, and the same levels of alkaloids were obtained in each case. The supercritical carbon dioxide method is, however, very efficient, more rapid and more environmentally friendly than conventional methods.  相似文献   

12.
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   

13.
超临界CO2萃取去除蛋黄粉中胆固醇和甘油三酯的研究   总被引:15,自引:0,他引:15  
采用超临界CO2萃取,对去除蛋白黄粉中胆固醇和甘油三酯进行了研究,市购鲜鸡蛋去壳、分别收集湿蛋白和蛋黄,在45℃下分别真空干燥,得蛋白粉和蛋黄粉,取蛋黄粉装入高压釜中,进行超临界CO2循环萃取,通过正交试验得最佳工艺条件是:A萃取压力为31.5MPa,B萃取温度40℃,C被萃取蛋黄粉重300g,D萃取时间3h,所得蛋黄粉中胆固醇和甘油三酯等中性脂的残留量质量分数仅为0.019%,与不含此类旨质的蛋白粉混合,制成几乎不含胆固醇和甘油三酯的高级绿色保健营养食品--鸡蛋粉。  相似文献   

14.
Conventional solvent extraction methods cannot attain high‐quality antioxidant extracts from microalgae and also require solvent recovery and posttreatment. In this study, we utilized environmental friendly supercritical carbon dioxide fluid extraction (SFE‐CO2) techniques to obtain pigment (i.e. astaxanthin) from Haematococcus pluvialis. The effects of key operating parameters on the extraction efficiency of astaxanthin were investigated, giving an optimal condition of H. pluvialis weight, 6.5 g; CO2‐flow rate, 6.0 NL/min; extraction time, 20 min; extraction pressure, 4500 psi; volume of ethanol modifier added, 9.23 mL/g; extraction temperature, 50°C; modifier composition, 99.5%. Under these optimum conditions, the astaxanthin yield was 73.9% (10.92 mg/g dry H. pluvialis powder) after eight cycle of extraction cycles. The saponification index (CS/C0, representing the ratio of astaxanthin concentration after and before the saponification procedures) of the extract could be increased from 1 to 12.78 by saponification with 3.5 M NaOH.  相似文献   

15.
秋橄榄果实中番茄红素的超临界萃取技术研究   总被引:1,自引:0,他引:1  
秋橄榄果实中番茄红素含量丰富。利用超临界二氧化碳技术萃取秋橄榄中的番茄红素,对影响萃取的诸因素,如萃取压力、萃取温度、萃取时间、夹带剂等进行研究,并进一步用响应曲面法优化萃取工艺条件。结果表明:丙酮作为夹带剂效果最佳,优化后的最佳萃取工艺条件是萃取压力37MPa,萃取温度52℃,萃取时间3.8h。  相似文献   

16.
沙蚕毒素的等温加湿超临界CO_2-萃取法研究   总被引:3,自引:0,他引:3  
本文研究了用等温加湿超临界CO2从海洋蠕虫状动物沙蚕体腔细胞中,提取沙蚕毒素的萃取条件(温度、压力、时间)对萃取过程的影响。探讨了等温加湿超临界CO2萃取法与传统提取方法比较的最佳选择分离方法。  相似文献   

17.
Lycopene, a carotenoid linked to protection against certain forms of cancer, is found in produce such as papaya, red-fleshed tomatoes, grapefruit and watermelon. The preparation of a supercritical CO2 (SC-CO2) watermelon-lycopene extract could serve as a food grade source of this carotenoid. This study established preliminary conditions for enhancing SC-CO2 extraction of lycopene from watermelon. Freeze-dried watermelon was extracted with SC-CO2 and ethanol as an organic co-solvent. The lycopene concentration was determined by HPLC, with absorbance measured at 503 nm. In an initial set of experiments, the effects of extraction temperature (70-90 degrees C), pressure (20.7-41.4 MPa) and co-solvent ethanol addition (10-15%) were evaluated. A lycopene yield of 38 microg per gram of wet weight was obtained at 70 degrees C, 20.7 MPa, and 15% by volume ethanol. The extraction of fresh (non-freeze-dried) watermelon yielded 103+/-6 microg lycopene per gram fresh fruit weight. Of the parameters tested, temperature had the most effect on lycopene yield. Thus, in another set of experiments, the temperature was varied from 60-75 degrees C at an extraction pressure of 20.7 MPa in the presence of 15% ethanol. Studies showed that freeze-dried watermelon flesh loses lycopene in storage. In accounting for lycopene storage losses, lycopene yields at 60 degrees C extraction temperature were 14% greater than those obtained at 70 degrees C.  相似文献   

18.
Experiments were carried out on a lab supercritical CO(2) extraction system to determine the effects of extraction conditions, including mass ratio of CO(2) consumed to distillers dry grain with solubles (DDGS) extracted, extraction pressure, extraction temperature and time, on yield and composition of extracted lipids. A maximum lipid yield of 150 g/kg DDGS was achieved with a mass ratio approximately 45, an extraction pressure at 27.5 MPa, an extraction temperature at 70 degrees C and an extraction time of 4 h. Under these extraction conditions, the contents of tocols, phytosterols, policosanols and free fatty acids were 0.44, 15.6, 31.2 and 155.3 mg/g in the extract. Experimental results indicated that shorter extraction time and higher flow rate of CO(2) can achieve higher contents of tocols, phytosterols and policosanols but lower content of free fatty acids in the lipid extract. Extraction conditions had no observed effects on the composition of free fatty acids in the extract. Palmitic, oleic and linoleic acids were three main free fatty acids extracted and constituted about 94% of all free fatty acids.  相似文献   

19.
This work investigated the extraction of cashew nut shell liquid (CNSL) using supercritical carbon dioxide (SC-CO(2)). Effects of process parameters such as extraction pressure, temperature and flow rate of SC-CO(2) were investigated. The yield of CNSL increased with increase in pressure, temperature and mass flow rate of SC-CO(2). However, under different operating conditions, the composition of CNSL varied. The study of physical properties and chemical composition of the oil obtained through super critical fluid extraction (SCFE) showed better quality as compared to the CNSL obtained through thermal route. Experimental results were compared with diffusion based mass transfer model. Based on this simple model, extraction time was optimized.  相似文献   

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