超声辅助下皂脚加压水解制备脂肪酸

为了回收利用油脂精炼过程中产生的副产品皂脚中的有效成分,利用超声波辅助技术将皂脚一步转化为脂肪酸,意在考量超声波辅助技术在皂脚酸化水解过程中的作用,并在超声辅助下探究工艺条件的影响。以产物酸价和得率作为考察目标,探究了超声辅助酸化水解对产物分布的影响。结果表明,超声的分散搅拌作用使得产物的酸价和得率得到提升。通过单因素和正交设计实验探究各因素对产物酸价和得率的影响,进而确定制备脂肪酸的最佳反应条件。实验结果表明,以甲酸为酸催化剂,在反应温度220℃、反应时间110min、超声功率1050W、超声持续时间7s的反应条件下,产物酸价和得率均得到最高值,分别为184mg KOH/g和79.9%;影响产物得率的因素从主到次：反应温度>超声持续时间>超声功率>反应时间。经气相色谱质谱联用仪分析表明,产物中脂肪酸含量达到97.4%;产物质量指标测定结果表明产物具有较高的质量,皂化值达到190mg KOH/g,碘值达到157g I/100g,不皂化物含量达到0.54%。     

酚酸类化合物在化妆品中的研究进展

简单介绍了酚酸类化合物的来源和生物活性,综述了酚酸类化合物作为一种天然化合物,通过清除自由基、抑制炎症反应、抑菌、抑制酪氨酸酶活性、加速分解肌肤中的晚期糖化终末产物等途径起到的美白淡斑、抗衰老、抗炎、屏障修护等多重护肤功效,并介绍了酚酸类化合物的安全性问题,提出了酚酸类化合物生物利用度低、低水溶性等实际应用问题,采用生物基纳米颗粒负载酚酸类化合物可使部分实际应用问题得到改善。最后阐述了目前酚酸类化合物在化妆品行业应用中存在的问题,以期为酚酸类化合物在护肤领域的应用提供参考。     

Enzymatic and Mechanical Extraction of Virgin Coconut Oil

The effect of different processing methods namely enzymatic method using crude protease extract (CPE) from overripe pineapple, microwave‐assisted extraction (MAE) and ultrasound‐assisted extraction (UAE) methods on the recovery yield of virgin coconut oil (VCO) is evaluated. The physicochemical properties of VCOs namely color, iodine value (IV), refractive index, saponification value, moisture content, free fatty acid, p‐anisidine value, lipid peroxidation, fatty acid composition, triacylglycerol (TAG) composition, melting and crystallization profile are compared. The total phenolic compounds and scavenging activity of the extracted VCOs are also examined. Results reveal that enzymatic approach exhibits the highest VCO yield (77.7% ± 0.38) at 50 °C for 2 h, followed by MAE (58.6%±0.07), control without enzyme (24.1%±0.19) and UAE (24.1%±0.12). The physicochemical properties of the VCOs extracted are found to conform to APCC standards established except IV. The antioxidant activity of VCO extracted with CPE shows no significant difference with MAE and UAE methods (p > 0.05). Lauric acid appears to be the most abundant fatty acid detected in all VCO samples. Similar exotherms and endotherms are observed in both melting and crystallization profiles with two distinct peaks exhibited. The TAG compositions of the extracted VCOs are mainly LaLaLa, LaLaM, CLaLa, CCLa, and LaMM (C = Capric acid; La = Lauric acid; M = Myristic acid). Practical Applications: The results obtained from this study indicate that VCO extraction using CPE from overripe pineapple is feasible. The enzymatic extraction protocol presented here would be useful for VCO production at industrial scale with a promising oil yield.     

Extraction of phenolic compounds from spent blackberry pulp by enhanced-fluidity liquid extraction

This research describes an enhance-fluidity liquid extraction process for extracting total phenolic compounds (TPC) from spent blackberry pulp (SBP) using a modified solvent (CO₂–ethanol mixture). Effects of particle size (from 1,400 to 180 μm), pressure (150–300 bar), and cosolvent (ethanol)-to-solid ratio (64, 128, and 192 mL ethanol/32 g solid) on the extraction of TPC at 40°C were investigated. Experimental data was processed using the Sovova's model to obtain the solubility of TPC in the modified solvent. The Peng–Robinson equation of state was used to correlate the solubility of phenolic compounds at high pressures. Results indicated that particle sizes ranging from 600 to 850 μm and pressure of 300 bar allowed obtaining extracts with higher antioxidant activity (94.71% of inhibition) and TPC content (11.59 mg GA/g SBP). High pressure and the modified solvent increased the solubility up to 3.4 × 10⁻⁴ (mol fraction).     

Extraction of amino acids from protein hydrolysates by electrodialysis

Protein hydrolysates were obtained by acid hydrolysis from animal or human residues, such as poultry feathers, ox blood and human hair. After neutralization and discolouration with active charcoal, the hydrolysates were treated by successive electrodialysis (ED) in order to extract amino acids into several fractions. The current density and pH were optimized for each ED operation performed with preindustrial pilot scale equipment. The first step was the demineralization of amino acid mixtures using an ED stack with two compartments. The salt removal was achieved with extraction degrees higher than 90% and current efficiencies of about 80%. In the most favourable case, the amino acid losses did not exceed 10%. The second step was the extraction of the charged amino acids using an ED stack with four compartments. Three fractions were obtained, corresponding to the acidic, basic and neutral amino acids. The extraction degrees varied from 80% to 100%. In the third step, the fractionation of basic amino acids on the one hand, and neutral amino acids on the other hand, was carried out with enrichment degrees varying from 50% to 80%. © 1998 SCI     

Effect of lipid unsaturation on the antioxidative activity of some phenolic acids

Antioxidative properties ofp-hydroxybenzoic, vanillic, syringic, 3,4-dihydroxybenzoic,p-coumaric, ferulic, sinapic and caffeic acids were studied in the concentration range 0.02–0.20 wt% during autoxidation at 100°C of lard and sunflower oil methyl esters (MEL and MESO, respectively). In both lipid systems, the derivatives of benzoic acid had weaker inhibiting properties than did the corresponding analogues of cinnamic acid. The effectiveness and strength of the antioxidative action were considerably lower in the lipid system MESO, which was rich in linoleic acid and was more easily oxidized. Thep-hydroxybenzoic, vanillic, syringic andp-coumaric acids in this system exercised no inhibiting effect. We established that the molecules of the investigated phenolic acids initiated the chain radical process of autoxidation, and the formed antioxidant radicals propagated the chains as a result of the reaction with the lipid substrate. These reactions proceeded at a higher rate in MESO than in MEL.     

利用麸皮水解液培养深黄伞形霉积累油脂

为了探讨利用麸皮水解液培养深黄伞形霉积累油脂情况,首先通过单因素实验研究了培养温度、pH和接种量对油脂产量的影响,进而通过响应面方法优化培养条件。采用Box-Behnken设计建立了3因素3水平响应面和回归模型。油脂产量最高的条件为培养温度27℃、最适pH 4.6,接种量2×10⁶mL^-1。经过5天发酵后,油脂产量达到最高值（9.81g/L）,菌体产量为24.93g/L,菌体中油脂含量（质量分数）为39.35%。通过高效液相色谱测定了水解液中残糖种类的变化,发现总糖利用率为69.40%,深黄伞形霉能够利用甘露糖、葡萄糖、木糖、阿拉伯糖以及部分多聚糖。残余糖中84.3%为多聚糖。气相色谱质谱联用仪分析发现油脂中不饱和脂肪酸含量（质量分数）为67.70%,多不饱和脂肪酸的含量（质量分数）为18.11%。多不饱和脂肪酸主要为亚油酸和γ-亚麻酸。本研究建立了由深黄伞形霉利用麸皮水解液积累油脂的途径,为综合利用麸皮提供了一个选择。     

Effect of ultrasound on the physicochemical properties of organosolv lignins from wheat straw

The extractability and physicochemical properties of the wheat straw lignins were comparatively studied by using extraction methods with 0.5M NaOH in 60% aqueous methanol with and without application of ultrasonic irradiation. The results showed that applying sonication for 5, 10, 15, 20, 25, 30, and 35 min solubilized 67.4, 68.6, 74.4, 77.3, 77.3, 77.9, and 78.5% of the original lignin, whereas the treatment with 0.5M NaOH in 60% aqueous methanol at 60°C for 2.5 h without ultrasound assistance released 61.0% of the original lignin. The lignin preparations isolated by ultrasound‐assisted extractions showed slightly lower molecular weights, associated polysaccharides, and thermal stabilities during the initial stage of decomposition. More important, there were no significant differences in the primary structural features between the lignin preparations. Ultrasound‐assisted extractions under the alkaline organosolv extractions did not affect the overall structure of the lignin from wheat straw. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2512–2522, 2002     

Production of vanillin from wheat bran hydrolyzates via microbial bioconversion

BACKGROUND: Wheat bran contains a large amount of ferulic acid, which can be released through enzymatic hydrolysis and bioconverted into vanillin. A previous study has shown that ferulic acid purification from bran carbohydrates with the Amberlite^® IRA 95 resin allowed an increased vanillin molar yield. In this work, alternative ferulic acid recovery methods were proposed and the possibility of exploiting the residual carbohydrate‐rich water phase was explored. RESULTS: Ferulic acid was recovered from crude wheat bran hydrolyzate by: (i) a hydrophobic sorbent cartridge (ISOLUTE ENV^+®): (ii) ethyl acetate extraction; and (iii) the resin previously employed. The highest recovery percentage (95%) was obtained with ISOLUTE ENV^+®, which also allowed an interesting vanillin molar yield from ferulic acid bioconversion (75% from 0.5 mmol L^?1 ferulic acid). The residual water phase was a good growth substrate for the microorganism operating the bioconversion. Cells grown on this matrix could efficiently bioconvert the recovered ferulic acid to vanillin CONCLUSION: The possibility of efficiently recovering ferulic acid from wheat bran hydrolyzates, bioconverting it into vanillin, and valorizing the sugar‐rich exhausted water fraction was demonstrated in this work. The approach allowed the production of a value‐added fine‐chemical from a food‐industry by‐product. Copyright © 2009 Society of Chemical Industry     

Lipase-catalyzed transesterification of trilinolein or trilinolenin with selected phenolic acids

The enzymatic transesterification of selected phenolic acids with TAG, including trilinolein (TLA) and trillinolenin (TLNA), was investigated in an organic solvent medium. Maximal bioconversion of 66% was obtained with a dihydrocaffeic acid (DHCA) to TLA ratio of 1∶2 after 5 d of reaction. Similarly, the highest bioconversion of 62% was obtained with a DHCA to TLNA ratio of 1∶2, but after 12 d of reaction. However, a ratio of 1∶4 DHCA/TLA decreased the bioconversion to 53%. Transesterification reactions of ferulic acid with both TAG, using a ratio of 1∶2, resulted in low bioconversion of 16 and 14% with TLA and TLNA, respectively. The overall results indicated that bioconversion of phenolic MAG was higher than that of phenolic DAG. The structures of mono- and dilinoleyl dihydrocaffeate as well as those of mono- and dilinolenyl dihydrocaffeate were confirmed by LC-MS analyses. The phenolic lipids demonstrated moderate radical-scavenging activity.     

Efficient recovery of phenol from phenolic wastewater by emulsion liquid membrane

The recovery of phenol from phenolic wastewater by emulsion liquid membrane (ELM) was investigated. The W/O emulsion was prepared with kerosene, Span−80, carrier, liquid paraffin, and NaOH solution. The effects of NaOH concentration, oil–internal solution ratio, shearing speed, Span−80 concentration, and carrier type and concentration on emulsion breakage were studied. In the single factor experiments of stability of W/O emulsion, the lowest percentages of emulsion breakage were achieved at a NaOH concentration of 0.03 g/ml, an oil–internal solution ratio of 2:1, a shearing speed of 1500 r/min, a Span−80 concentration of 8%, a tributyl phosphate (TBP) concentration of 0.8%, and an ethyl acetate concentration of 0.8%, respectively. Then, the effects of nine factors on extraction efficiencies of phenol were investigated. This indicated that the effects of shearing speed, oil-internal solution ratio, emulsion-external solution ratio, liquid paraffin concentration, and mixing speed on extraction efficiencies of phenol were limited. However, the carrier concentration, NaOH concentration, Span−80 concentration, and phenol concentration had important impacts on the extraction efficiency of phenol. The extraction efficiency of phenol could reach 99.7%. Besides, the results of orthogonal experiments indicated that during the extraction of phenol by ELM, the order of importance of factors was NaOH concentration > emulsion-external solution ratio > volume fraction of Span−80 > volume fraction of TBP. After extraction, the recycled emulsion with Span−80 could not easily be effectively demulsified through heating, which only provided the highest demulsification efficiency of 18.2%. However, the recycled emulsion could be effectively demulsified through centrifugation, which could get the highest demulsification efficiency of 86% at a centrifugal rotational speed of 2000 r/min and a centrifugal time of 25 min.     

Molecularly Imprinted Polymer for Solid-Phase Extraction of Phenolic Acids from Salicornia herbacea L.

This paper reports the application of a molecularly imprinted polymer (MIP) for the extraction and separation of phenolic acids from Salicornia herbacea L. (S. herbacea) using a solid phase extraction (SPE) system. The template of the MIP for phenolic acid extraction and separation was selected experimentally as one of seven templates. The obtained material with Benzoic acid (BA) as a template had the best extraction capacity of phenolic acids from S. herbacea. Water and methanol/HCl were selected as a washing solvent and elution solvent, respectively. The good linearity was obtained for the three targets, ranging from 10 to 500 μg mL^?1 (R² > 0.999), with relative standard deviations ≤ 5.0%. Overall, the proposed method using MIPs is expected to have a wide range of applications.     

Extraction of pollen lipids by SFE‐CO2 and determination of free fatty acids by HPLC

Rape bee pollen lipids obtained by petrol ether extraction (PEE) or supercritical fluid (carbon dioxide) extraction (SFE) were compared with regard to their free fatty acid (FFA) components. Optimal SFE conditions were selected by carrying out the Taguchi method with an OA9 (3³) matrix design, and are as follows: extraction pressure at 35 MPa, temperature at 45 °C, and dynamic extraction time at 90 min. The lipid yield based on PEE was 7.42 wt‐% and the extracts of the desired analytes based on SFE varied in the range of 3.23–5.58 wt‐% under different conditions. With the optimized procedure, the lipid yield was 6.09 wt‐%. The FFA in the lipids were separated with a pre‐column derivation method and 1‐[2‐(p‐toluenesulfonate) ethyl]‐2‐phenylimidazole [4,5‐f]9,10‐phenanthrene as labeling regent, followed by high‐pressure liquid chromatography (HPLC) with fluorescence detection. HPLC analysis shows that the lipids contain abundant unsaturated fatty acids (UFA) in high to low concentrations as follows: linolenic acid (18:3), oleic acid (18:1), linoleic acid (18:2), nervonic acid (24:1), and lignoceric acid (20:4). The UFA contents in the SFE extracts were higher than those after PEE. The results indicated that SFE under suitable conditions is more selective than conventional PEE with regard to lipid extraction and preservation of their quality.     

Removal of ciprofloxacin from aqueous solution using wheat bran as adsorbent

Current study describes sorption of antibiotic drug (ciprofloxacin) by using nontoxic and biocompatible carrier, i.e., wheat bran (WB). For sorption study, various parameters were optimized and Freundlich, Dubinin–Radushkevich, Langmuir, and Temkin isotherm models were applied to demonstrate the mechanism of sorption, while kinetics study for sorption was evaluated using diffusion models, pseudo-first-order kinetic (Langergren) and pseudo-second-order (Ho and McKay) kinetic models. In addition, thermodynamics study was also carried out. However, sorption of ciprofloxacin was pH depended and it showed 75% drug release in alkaline medium (at pH = 1.5) indicating the good release ability of WB for ciprofloxacin.     

微波诱导法萃取印楝种壳中印楝素的研究

研究了利用微波诱导法萃取印楝种壳中印楝素的新方法 ,以HPLC分离并测定所萃取的印楝素含量。结果表明 ,与常用的甲醇室温浸提法和丙酮 45℃萃取法相比 ,微波诱导萃取法不仅萃取率高 ,而且萃取速度快 ,效率高     

超临界CO_2和微波辅助萃取当归挥发油

考察当归挥发油的不同提取方法。文中用超临界CO2流体萃取法和微波辅助萃取法研究萃取当归挥发油。实验表明:超临界CO2萃取最佳工艺条件为萃取压力25 MPa、分离釜Ⅰ解析温度55℃、萃取温度45℃,提取率约1.9%;微波辅助萃取最佳工艺条件为无水乙醇为提取溶剂,微波功率800 W、微波辐射时间150 s、液料质量比为4.71∶1,提取率约11.2%。微波辅助萃取法取得当归油的收率高于超临界CO2萃取法。微波辅助萃取法萃取当归挥发油收率高,但外观品质较超临界萃取的当归挥发油差。