超高压提取蓝莓渣花色苷的工艺优化及其抗氧化活性

本文旨在优化蓝莓渣花色苷的超高压提取工艺并考察其抗氧化活力。本文以蓝莓渣为原料,采用单因素实验和Box-Behnken响应面分析法对蓝莓渣花色苷的提取工艺进行优化,以维生素C（V_C）为阳性对照,通过DPPH自由基清除率、羟基自由基清除率和FRAP铁离子还原能力的测定,评估蓝莓渣花色苷的体外抗氧化活性,并采用高效液相色谱法（HPLC）对蓝莓渣花色苷组分进行分析。结果表明:蓝莓渣花色苷的最佳提取工艺条件为:提取压力400 MPa,提取时间9 min,乙醇浓度60%,料液比1:20 g/mL,此条件下花色苷的提取量为5.93±0.06 mg/g,与传统溶剂浸提法（CSE）、超声波辅助提取法（USE）相比,超高压辅助提取（UPE）法的提取效果更好,花色苷提取量分别提高25.11%、10.02%;蓝莓渣花色苷对DPPH?清除能力最强,与同浓度的V_C相比,无显著性差异（P>0.05）;其对?OH的清除率以及FRAP铁离子还原能力则显著弱于同浓度V_C（P<0.05）;HPLC分析结果表明,蓝莓渣花色苷包含13种花色苷单体,其中锦葵色素-3-半乳糖苷含量最高。因此,超高压辅助提取是一种高效的蓝莓渣花色苷提取方法,且蓝莓渣花色苷因其较强的抗氧化活性具有较好的应用价值。     

Fractioned High Pressure Extraction of Anthocyanins from Elderberry (<Emphasis Type="Italic">Sambucus nigra</Emphasis> L.) Pomace

Fractionated high pressure extractions from dry and in natura elderberry pomace were performed in order to obtain anthocyanin rich extracts. Experiments were carried out using CO₂ supercritical fluid extraction followed by enhanced solvent extraction (ESE) with CO₂/EtOH–H₂O mixtures (1–100%, v/v), to obtain anthocyanin rich fractions in the second step, at 313 K and ~20 MPa. Higher extract yields, anthocyanin contents and antioxidant activities occurred by the presence of water, both in the raw material and in the solvent mixture. The CO₂ dissolved in the ESE solvent mixture favored either anthocyanin contents or antioxidant activities, which were not directly related. Comparing to the literature data for elderberries and grapes, these fractions had higher anthocyanins contents. From these results, an added economical value to this agroindustrial residue is proposed, using solvents and techniques “generally regarded as safe” in the food and pharmaceutical industries.     

遗传算法优化双水相法提取葡萄皮渣花色苷工艺及其组分分析

以葡萄皮渣为原料,采用双水相法提取其中的花色苷并鉴定花色苷组分。在单因素实验的基础上,通过遗传算法优化双水相法提取葡萄皮渣花色苷的工艺;利用高效液相色谱-质谱联用鉴定葡萄皮渣花色苷提取物中花色苷组分。结果表明:双水相法提取葡萄皮渣花色苷的最佳工艺为:乙醇体积分数40%、硫酸铵质量分数26%、pH3.0、料液比1:38 g/mL,在此条件下花色苷得率（3.05±0.07） mg/g。经鉴定发现葡萄皮渣花色苷提取物含有2种花色苷组分,分别为飞燕草-3-葡萄糖苷和矢车菊素-3-葡萄糖苷,其纯度分别为90.16%和92.41%。研究结果为天然花色苷提取提供一种新的提取方式,并为进一步开发花色苷功能性食品提供依据。     

超高压辅助提取牛蒡叶中多酚及其抗菌活性研究

研究在常温下用超高压技术提取牛蒡叶多酚的最佳工艺,探讨不同提取压力、保压时间和料液比等因素对提取率的影响。利用超高压辅助技术从牛蒡叶中提取多酚类物质的较佳工艺条件为:以体积分数70%的乙醇溶液为提取液,料液比1∶20,提取时间10min,压力550 MPa。在此条件下,牛蒡叶中多酚的提取率最高可达85.4%。用此工艺条件提取的牛蒡叶多酚,对金黄色葡萄球菌、大肠杆菌、志贺氏菌的MIC结果为2 mg/mL、2 mg/mL、2.5 mg/mL。     

Optimization of Extraction of Bioactive Compounds from Different Types of Grape Pomace Produced at Wineries and Distilleries

Natural extracts obtained from grape pomace are particularly interesting, due to the substantial variety of valuable compounds present with health benefits, specifically phenolic compounds such as anthocyanins, trans‐resveratrol, quercetin, and proanthocyanidins. The production of such extracts has been recognized as a profitable way to valorize grape byproducts, which are low‐value and most abundant. First, the effect of the solvent on the extraction of bioactive compounds from grape pomace is studied. The selected solvents are water and ethanol, biocompatible and available in wineries and distilleries. Then, different types of grape pomace obtained along the various stages of current industrial winemaking and distillation processes are analyzed. As a result, the best stage of the winemaking and distillation processes for pomace valorization is identified, corresponding to the grape byproduct with the highest potential as source of bioactive compounds. These studies were performed with Vitis vinifera variety of Tempranillo grapes (same year, same vineyard).     

超高压辅助提取对提取溶剂物理特性的影响

以超高压辅助提取蓝莓果渣花色苷为研究对象,从超高压处理对提取溶剂物理性质影响角度对超高压辅助提取机理进行研究。结果表明超高压辅助提取过程会影响提取溶剂的最大吸收波长、pH值、电导率等物理性质;通过氢谱核磁共振谱和红外光谱测定发现超高压处理会影响醇水之间氢键,随着提取压力增加,醇水之间氢键更加稳定,其中花色苷提取率和醇水氢键羟基红外吸收、醇水氢键化学位移具有显著相关性。从提取溶剂角度考虑,超高压处理能够增加花色苷提取率是由于压力引起提取溶剂分子间氢键的变化,进而导致提取溶剂物理性质发生变化,从而提高花色苷提取率。     

Extraction of anthocyanins from grape by-products assisted by ultrasonics,high hydrostatic pressure or pulsed electric fields: A comparison

Extracts from grape by-products contain bioactive substances such as anthocyanins which could be used as natural antioxidants or colourants. The effect of heat treatment at 70 °C combined with the effect of different emerging novel technologies such as ultrasonics (35 KHz), high hydrostatic pressure (600 MPa) (HHP) and pulsed electric fields (3 kV cm^− 1) (PEF) showed a great feasibility and selectivity for extraction purposes. After 1 h extraction, the total phenolic content of samples subjected to novel technologies was 50% higher than in the control samples. Therefore, the application of novel technologies increased the antioxidant activity of the extracts being the extractions carried out with PEF four-fold, with HHP three-fold and with ultrasonics two-fold higher than the control extraction. In addition, the extraction of individual anthocyanins was studied showing a selective extraction based on the glucose moieties linked to the anthocyanidins; anthocyanin monoglucosides were better extracted by PEF, whereas the acylated ones were extracted by HHP.Industrial relevanceThis study examines the feasibility of different emerging technologies such as high hydrostatic pressure, pulsed electric fields and ultrasonics as potential extraction methods for bioactive substances from grape by-products. Grape by-products represent a low-cost source of valuable bioactive compounds such as anthocyanins, with great industrial applications as colourants or nutraceuticals. The higher yields obtained in extractions carried out by high hydrostatic pressure and pulsed electric fields are of major interest from an industrial point of view, since solvent amounts were reduced and extraction times shortened. Thus, the combination of emerging technologies for extraction purposes and low-cost raw materials is an economical alternative to traditional extraction methods according to industry demands and a sustainable development.     

A comparison between high hydrostatic pressure extraction and heat extraction of ginsenosides from ginseng (Panax ginseng CA Meyer)

BACKGROUND: To determine biomaterial components, the components must first be transferred into solution; thus extraction is the first step in biomaterial analysis. High hydrostatic pressure technology was used for ginsenoside extraction from ginseng roots. In the extraction of fresh and red ginseng, high hydrostatic pressure extraction (HHPE) was found to be more effective than heat extraction (HE). RESULTS: In fresh ginseng extraction under HHPE, total ginsenosides (1602.2 µg mL^?1) and ginsenoside metabolite (132.6 µg mL^?1) levels were slightly higher than those under HE (1259.0 and 78.7 µg mL^?1), respectively. In red ginseng, similar results indicated total ginsenoside and ginsenoside metabolite amounts according to the extraction methods. Most volatile compounds by HHPE were higher than by HE treatment. HHPE of red ginseng was conducted under four pressures: 0.1 MPa (1 atm), 30, 50, and 80 MPa. Total sugar, uronic acid, and polyphenol amounts increased until 30 MPa of pressure and then showed decreasing tendencies. Total ginsenoside and ginsenoside metabolite contents linearly increased with increasing pressure, and a maximum was reached at 80 MPa for the metabolites. CONCLUSION: HHPE used for red ginseng processing contributes to enhanced extraction efficiencies of functional materials such as ginsenosides through cell structure modification. Copyright © 2011 Society of Chemical Industry     

Improvement of anthocyanin yield and shelf-life extension of grape pomace by gamma irradiation

This research investigated the effect of gamma irradiation on anthocyanin extraction from grape pomace, and on inhibition of microbial growth and anthocyanin content during subsequent storage. The combination of four variables was investigated: (1) irradiation at doses from 0 to 9 kGy; (2) packaging under vacuum; (3) addition of a low dose of sodium metabisulfite during irradiation; and (4) extraction in the presence of SO₂. Results indicate that the irradiation at 6 kGy, packaging in the presence of 0.1% sodium metabisulfite and extraction in the presence of 2000 ppm of SO₂ yielded the highest value of anthocyanins, and improved shelf-life of grape pomace.     

Influence of ethanol/water ratio in ultrasound and high‐pressure/high‐temperature phenolic compound extraction from agri‐food waste

The valorisation and management of agri‐food waste are currently hot investigation topics which probe the recovery of valuable compounds, such as polyphenols. In this study, high‐pressure/high‐temperature extraction (HPTE) and ultrasound‐assisted extraction (UAE) have been used to study the recovery of phenolic compounds from grape marc and olive pomace in hydroalcoholic solutions. The main phenolic compounds in both extracts were identified by HPLC‐DAD. Besides extraction yield (total polyphenol and flavonoid content) and the antiradical power, polyphenol degradation under HPTE and UAE has also been studied. HPTE with ethanol 75% gave higher phenolic extraction yields: 73.8 ± 1.4 mg of gallic acid equivalents per gram of dried matter and 60.0 mg of caffeic acid equivalents per gram of dried matter for grape marc and olive pomace, respectively. In this study, the efficient combination of ethanol/water mixture with HPTE or UAE has been used to enhance the recovery of phenolic compounds from grape marc and olive pomace. HPLC‐DAD showed that UAE prevents phenolic species degradation damage because of its milder operative conditions.     

Kinetics of ultrasonic extraction of polyphenols,anthocyanins and tannins from five different New Zealand grape pomaces

Polyphenols were extracted from five kinds of New Zealand grape pomace (Sauvignon Blanc, Pinot Gris, Gerwurztraminer, Merlot and Pinot Noir) at 30, 50 and 70 °C in an ultrasonic generator. The extraction kinetics for total phenol, anthocyanin and tannin were determined. The results of dynamics study showed that the extraction of total polyphenols, anthocyanin and tannin followed first-order reaction kinetics during the extraction at 30, 50 and 70 °C. The total phenolic content, anthocyanin conten, and tannin content of water–ethanol extracts from grape pomaces were compared, and the parameters in the extraction kinetics equations were determined. The extraction results showed that the Pinot Noir pomace extract had the highest total phenolic content of 59.95 mg GAE g⁻¹ pomace and tannin content of 79.93 mg EE g⁻¹ pomace. The anthocyanin content in Merlot pomace extract was the highest, which was 4.50 CE g⁻¹ pomace. The results might be of great significance for the development of grape pomace or its polyphenol and/or anthocyanin components as an antioxidant source with natural and inexpensive benefits.     

Anthocyanin colourants from elderberry (Sambucus nigra L.). 1. Process considerations for production of the liquid extract

Elderberry is shown to be a good source of anthocyanins (Acy), having between 2–10 mg Acylg berry. Anthocyanin concentration is very dependent on variety and maturity. Pressing of the berries gives a significant difference between weight distribution (pomace = 25–40% of total weight) and anthocyanin distribution (Acy in pomace = 75–98% of total Acy). Freezing of the berries prior to pressing gives much less pomace weight, with only a small reduction of anthocyanin distribution in the pomace. Tests of various extraction media (HCl acidified alcohols, aqueous HC1 and aqueous citfic acid) showed the highest anthocyanin recovery for aqueous HCl(0.1 M). Multiple extraction tests show that most of the anthocyanin is extracted from the pomace within two to three steps. The influence of extraction time and extraction temperature is discussed.     

蓝莓果渣花色苷提取工艺优化及抗氧化活性比较研究

以蓝莓干果渣为原料,酸化乙醇为溶剂,应用超声辅助法提取花色苷,利用pH示差法测定花色苷含量,通过单因素实验和响应面试验优化得出蓝莓干果渣花色苷提取工艺条件,比较相同干重的蓝莓干果渣、湿果渣采用超声辅助提取和无超声辅助工艺得到的提取液的总多酚、花色苷含量及抗氧化活性。结果表明,蓝莓干果渣最佳提取工艺为液料比(31:1)mL/g,乙醇浓度63%,pH2.6,超声功率500 W,提取时间20 min,在此条件下蓝莓果渣提取液中花色苷含量为498.84 mg/100 g。相同原料,超声辅助提取工艺提取液较无超声辅助提取工艺提取液的总多酚和花色苷含量多;相同工艺条件下,相同干重的湿果渣总多酚和花色苷含量较干果渣低,但却拥有更高的抗氧化活性。     

Procyanidin Content of Grape Seed and Pomace, and Total Anthocyanin Content of Grape Pomace as Affected by Extrusion Processing

ABSTRACT: Grape juice processing by‐products, grape seed and pomace are a rich source of procyanidins, compounds that may afford protection against chronic disease. This study was undertaken to identify optimal extrusion conditions to enhance the contents of monomers and dimers at the expense of large molecular weight procyanidin oligomers and polymers in grape seed and pomace. Extrusion variables, temperature (160, 170, and 180 °C in grape seed, and 160, 170, 180, and 190 °C in pomace) and screw speed (100, 150, and 200 rpm in both) were tested using mixtures of grape seed as well as pomace with decorticated white sorghum flour at a ratio of 30 : 70 and moisture content of 45%. Samples of grape seed and pomace were analyzed for procyanidin composition before and after extrusion, and total anthocyanins were determined in pomace. Additionally, chromatograms from diol and normal phase high‐performance liquid chromatography were compared for the separation of procyanidins. Extrusion of both grape by‐products increased the biologically important monomer and dimers considerably across all temperature and screw speeds. Highest monomer content resulted when extruded at a temperature of 170 °C and screw speed of 200 rpm, which were 120% and 80% higher than the unextruded grape seed and pomace, respectively. Increases in monomer and dimer contents were apparently the result of reduced polymer contents, which declined by 27% to 54%, or enhanced extraction facilitated by disruption of the food matrix during extrusion. Extrusion processing reduced total anthocyanins in pomace by 18% to 53%. Practical Applications: Extrusion processing can be used to increase procyanidin monomer and dimer contents in grape seed and pomace. Procyanidins in grape by‐products have many health benefits, but most are present as large molecular weight compounds, which are poorly absorbed. Extrusion processing appears to be a promising technology to increase levels of the bioactive low molecular weight procyanidins.     

毛葡萄皮渣花色苷的真空辅助提取工艺优化

为充分利用“野酿2号”毛葡萄汁生产副产物——皮渣中的花色苷成分,该研究利用60 L真空提取和浓缩装置对毛葡萄皮渣花色苷进行提取、浓缩,以花色苷含量为评价指标,通过单因素试验和正交试验对其提取工艺进行优化,并对其浓缩效果进行比对。结果表明,毛葡萄皮渣花色苷的最佳真空辅助提取条件为：料液比1∶6(V/V),乙醇体积分数65%,pH值为1.0,油浴温度65℃,真空度0.08 MPa,提取时间120 min。在此优化条件下,花色苷的提取得率、浓缩得率分别为1.59%、1.42%,浓缩时间为5.12 h,浓缩损失率为10.92%。该研究为毛葡萄皮渣花色苷的工业化生产提取和浓缩提供了一定的技术参考。     

Anthocyanin dyes extracted from grape pomace for the purpose of textile dyeing

BACKGROUND: Pomace from different grape varieties was studied with regard to the content of extractable anthocyanins. RESULTS: Total anthocyanin concentrations of 24.5–126 mg dm^?3 were found in the extracts. The amount of extractable pigment was dependent on the variety of grape. The extracts were applied in textile dyeing operations using cotton fabric pre‐mordanted with tannin as textile substrate. Red/violet shades were obtained that showed good water‐fastness; however, limited light‐fastness indicated need for improvement to fulfil requirements for textile application. CONCLUSION: Colour measurement by means of CIE‐Lab coordinates and Kubelka–Munk value showed a direct correlation between extractable anthocyanin concentration and colour depth of the dyed material. Thus the analytically determined concentration of anthocyanins in the aqueous extract can serve as a measure of quality of grape pomace as raw material for textile dyeing application. Copyright © 2007 Society of Chemical Industry     

Application of high hydrostatic pressure and ultrasound-assisted extractions as a novel approach for pectin and polyphenols recovery from tomato peel waste

In this study, high hydrostatic pressure extraction (HHPE) and ultrasound-assisted extraction (UAE) were used for the improvement of pectin and polyphenol recovery from tomato peel waste.HHPE enhanced pectin recovery by 15% after 45 min of recycling, in comparison with the conventional extraction (CE) for 180 min. Similar mass fractions of anhydrouronic acid, total sugars and total phenols were obtained by using both methods. FTIR and ¹H NMR data confirmed that chemical composition of pectin obtained by HHPE and CE is identical, therefore it was concluded that the faster HHPE method can be used for its further isolation.Although depectinized residues subjected to UAE in 70% ethanol for 15 min contained two times lower values of total phenols (1625.7 mg/100 g) than pectinized samples (3643.9 mg/100 g), their quantities are not negligible, considering the fact that they are generated after HHPE. At the end of UAE, the residues were exploited as a source of fatty acids, among which lauric, palmitic and stearic acids are dominant.In conclusion, by shortening the extraction time using HHPE and UAE, it is possible to efficiently produce two valuable functional ingredients, pectin and polyphenols, and at the same time to reduce peel waste from tomato canning industry, which presents an environmental problem.Industrial relevanceUtilizing HHPE and UAE as novel and emerging technologies, and combining them with traditional ones (Soxhlet) is given the solution for sequential isolation of pectin, polyphenols and fatty acids from tomato peel waste, generated by canning factory.Shortening of extraction time using HHPE and UAE, it is possible to replace the conventional techniques, and achieve efficient production of pectin and polyphenols.Overall, the extraction methodology proposed in this work could provide two valuable benefits, i.e. the producers could find mode for decreasing of disposal costs of waste and consumer would take opportunity that isolated compounds could be reintroduced into food.     

Anthocyanin colorants from Elderberry (Sambucus nigra L.) IV. Further studies on production of liquid extracts, concentrates and freeze dried powders

Anthocyanin extraction from elderberry pomace is improved by mechanical disintegration and use of aqueous HCl in place of acidified ethanol as extractant, with pH being important in determining extractant effectiveness. Extraction at low solvent:pomace ratios gives extracts of higher concentration and lower volume, but with reduced efficiency. Enzyme pretreatments do not improve extractability from exten-sively crushed pomace, and if of extended duration, can result in anthocyanin break-down. Vacuum evaporation of extracts gave little loss of anthocyanins, and combined with freeze drying, produced materials with high anthocyanin retention.     

Subcritical Water and Sulfured Water Extraction of Anthocyanins and Other Phenolics from Dried Red Grape Skin

ABSTRACT: Water, an inexpensive and environmentally friendly solvent is an ideal solvent for industrial extraction of phenolics, but its use is limited due to poor extraction efficiency at low temperatures. In this study, subcritical water (SW) and subcritical sulfured water (SSW) (containing 1400 μg/mL sodium metabisulfite) extractions of grape skin phenolics were conducted over the temperature range of 100 to 160°C in 10°C increments for a short time (40 s), and compared with conventional hot water or aqueous 60% (v/v) methanol extractions (50°C, 1 h). The composition and contents of anthocyanins, flavonols, hydroxycinnamates, phenolic acids, and antioxidant capacities (Oxygen Radical Absorbing Capacity [ORAC]) in the extracts were determined. Increasing SW extraction temperature from 100 to 160°C resulted in a linear increase in ORAC values, but extraction temperatures > 110°C resulted in decreased contents of individual and total anthocyanins. Subcritical sulfured water extracts had higher levels of total anthocyanins and total phenolics than SW extracts. The SW and SSW extracts had comparable or higher levels of anthocyanins and ORAC values than extracts obtained using conventional hot water or 60% methanol. Subcritical water at 100 to 110°C appears to be an excellent alternative to organic solvents to extract anthocyanins and other phenolics from dried red grape skin and possibly other grape processing byproducts.