微波法萃取紫色甘薯皮原花青素工艺的研究

采用微波提取技术提取紫色甘薯皮中原花青素,研究微波控制条件对原花青素提取率的影响,并在单因素的基础上进行正交实验。研究结果表明:微波提取可以有效缩短原花青素提取时间并提高提取率,微波提取紫色甘薯皮原花青素的最佳提取工艺条件为以60%乙醇为提取液,微波功率600W、料液比为1∶14、微波作用时间140s、提取1次,在此条件下,原花青素的提取率为2.86%。     

不同纯度花生红衣原花青素的制备工艺研究

研究了AB-8大孔吸附树脂分离纯化得到不同纯度花生红衣原花青素的制备工艺,并对产物进行了HPLC-MS分析鉴定。结果表明:最佳分离纯化条件为上样流速0.5 m L/min、洗脱流速1.0 m L/min、洗脱液20%和40%乙醇溶液,解吸后得到的原花青素纯度分别为98.7%和86.2%;此外,不同的收集方式也可得到不同纯度的原花青素;经AB-8大孔吸附树脂分离得到的纯化物均为低聚体原花青素,20%乙醇纯化物的主要成分为A型原花青素二聚体和A型原花青素三聚体,40%乙醇纯化物的主要成分为A型原花青素二聚体和A型原花青素四聚体。     

黑花生衣原花色素和花色苷的提取工艺研究

为了同时提高黑花生衣原花色素和花色苷的得率,采用单因素试验和响应面分析试验对黑花生衣原花色素和花色苷的提取工艺进行优化。在单因素试验的基础上,固定pH值为3、提取时间120 min,选取液料比、乙醇体积分数和提取温度设计响应面试验,考察各自变量及其交互作用对原花色素和花色苷得率的影响。获得最佳提取参数为：液料比52∶1（mL∶g）、乙醇体积分数48%、提取温度44 ℃。此条件下黑花生衣中原花色素和花色苷的提取率分别为13.769 mg/100 mg、0.660 mg/100 mg。     

Separation and characterisation of proanthocyanidins in Virginia type peanut skins by LC-MS

Proanthocyanidins were extracted from peanut skins, an agricultural waste product of Virginia. Proanthocyanidin composition of single solvent and multistep extraction procedures of peanut skins were compared by HPLC-UV-vis absorbance. The multistep extraction procedure yielded more proanthocyanidin peaks and larger peak areas. Thus this extraction procedure was chosen for subsequent fractionation. Fractionation was performed by size exclusion (Toyopearl HW-40S) and normal phase (NP) (porous silica) high performance liquid chromatography (HPLC) before reversed phase (RP) electrospray ionisation liquid chromatography-mass spectrometry analysis (ESI-LC-MSⁿ). Proanthocyanidin separation on the NP column was better overall, compared to size exclusion chromatography, and thus was chosen for characterisation by MS. Peanut skin procyanidins were found to separate in order of increasing molecular weight on the NP column. The ESI-MS generated positive and negative molecular-type ions and their dissociation product ions were used to identify specific proanthocyanidins and procyanidins. New proanthocyanidin dimeric and trimeric species were identified. These species consisted of one or two (epi)catechin units bound to luteolin or kaempferol. Monomers through nonamers of flavan-3-ols were identified by retention time and their multistep (MSⁿ) dissociation pathway. Hexamers were identified as both singly and doubly charged negative ions, [M−zH]^z−, z = 1 or 2. Species of greater than pentamers were tentatively identified due to their low ionisation efficiency and significant overlap of species both chromatographically and in the MS spectra.     

Optimization of extraction of phenolic antioxidants from peanut skins

This work was conducted to optimize the extraction conditions for the best recovery of antioxidant compounds from peanut skins. The extracts from the peanut skins were obtained by different extraction methods. The extraction conditions were: different ethanol proportions as the solvent (0, 30, 50, 70 and 96% v/v in distilled water), different peanut skin particle sizes (0–1, 1–2 and 2–10 mm and non‐crushed skins), different proportions of solvent/skins (20, 30, 40, 50 and 60 ml g^?1), different extraction times (by maceration and shaking) and different numbers of extractions. The different extracts obtained under different extraction conditions were compared with special regard to yield, total phenolic compounds and radical scavenging activity. The results showed that the best delivery of phenolic compounds was reached using 70% ethanol, non‐crushed peanut skins, ratio of solvent/solid of 20 ml g^?1, at 10 min shaking and three extractions. The maximum yield of 0.118 g g^?1 was recorded for phenolic compounds when extracted at the optimum conditions. Copyright © 2004 Society of Chemical Industry     

大孔吸附树脂分离花生种皮原花青素的研究

研究比较了4种大孔吸附树脂对花生种皮原花青素分离的影响,筛选出最适的分离原花青素大孔吸附树脂AB-8型,并确定了AB-8型大孔吸附树脂的最佳工艺条件:样品浓度为2.5 mg/mL,上样流速为0.5 mL/min。采用20%、30%、50%浓度的乙醇溶液进行洗脱,得到3个不同的原花青素洗脱级分别为PSPP1、PSPP2、PSPP3,其中原花青素的含量分别为75.26%、84.50%和90.18%。通过薄层层析分析得知,提纯的原花青素样液有三条谱带,初步推断为单体、低聚体混合物及高聚体。     

花生种衣活性成分提取工艺参数优化

花生种衣富含黄酮类化合物、原花色素和白藜芦醇等多酚活性物质.本研究以花生种衣为原料,通过单因素试验考察乙醇浓度、水浴温度、提取时间和料液比对花生种衣中多酚物质提取效果影响,并通过响应面法对提取多酚工艺加以优化;结果表明,提取多酚最佳工艺条件为:乙醇体积分数55％、料液比1:20、水浴温度60℃、提取时间2h,在此条件下...     

Potential of peanut skin phenolic extract as antioxidative and antibacterial agent in cooked and raw ground beef

This study investigated the potential of peanut skin extract (PSE) as inhibitor of lipid oxidation in cooked and raw ground beef (GB) and as antimicrobial agent in raw GB. Results show that addition of PSE to raw GB before cooking significantly inhibited the formation of peroxides and TBARS in cooked GB during the refrigerated storage. PSE at concentration ≥0.06% was as effective as BHA/BHT at 0.02% in inhibiting lipid oxidation. PSE also inhibited the oxidation of meat pigments thereby preserving the fresh redness of treated meat when used at 0.02–0.10%. Microplate assay showed complete inhibition of test bacteria (Bacillus subtilis, Salmonella typhimurium, Staphylococcus aureus, Streptococcus faecalis and Escherichia coli) in the presence of PSE at 0.4% or higher. However, the antimicrobial effect of PSE in GB was less potent. Hence, PSE can primarily serve the dual purposes of preserving the colour of raw GB and preventing lipid oxidation in cooked products.     

超声辅助提取花生红衣色素工艺的优化

以花生红衣为原料,利用响应面分析法对超声辅助提取花生红衣色素的工艺进行优化。在单因素试验、PlackettBurman试验设计和最陡爬坡试验的基础上,以花生红衣色素综合提取效果值为响应值,利用响应面法研究各因素及其交互作用对花生红衣色素提取效果的影响,建立预测模型,选出最佳工艺条件。结果表明:超声辅助提取花生红衣色素的最佳条件为以乙醇为溶剂,乙醇浓度68%,料液比130(g/mL),超声时间27min,超声温度55℃。该条件下花生红衣色素的总提取率为21.6%,色价为34.6,原花色素得率为17.77mg/g,综合提取效果值为24.65,经验证实验结果表明,该试验建立的花生红衣色素的响应模型较成功。     

微波辅助提取花生衣原花色素工艺优化

探索花生衣原花色素微波辅助提取的最佳条件,在单因素试验的基础上,应用响应面法优化花生衣中原花色素的提取条件;研究发现料液比和萃取温度对花生衣原花色素的提取率都有显著影响,且非线性关系,最佳提取工艺参数为微波输出功率600W、乙醇体积分数40%、料液比1:24.5、提取时间91s、提取温度40℃。在此条件下原花色素的提取率为12.59%。表明响应面法对花生衣原花色素提取条件的优化是可行的,得到的原花色素提取条件具有实际应用价值。     

超声波辅助酶法提取花生红衣中白藜芦醇的工艺优化

为提高花生油提取副产物花生红衣的利用价值,以乙醇体积分数、料液比、超声时间、超声温度、酶的种类为考察因素,白藜芦醇提取量为指标,通过单因素实验对超声波辅助酶法提取花生红衣中白藜芦醇工艺进行优化。结果表明,在酶解pH 5. 0、酶添加量2%下,得到的最佳工艺条件为:乙醇体积分数80%,料液比1∶25,超声时间30 min,超声温度50℃,采用半纤维素酶提取。在最佳工艺条件下,白藜芦醇提取量为(0. 854±0. 025) mg/100 g。     

天然抗氧化剂联合作用对花生油氧化稳定性及风味特性的影响

以花生油为研究对象,在60 ℃加速氧化条件下探讨天然复合抗氧化剂协同提高其氧化稳定性的作用机制,分析了贮藏期内风味特性的变化趋势。结果表明,花生油在24 d加速氧化实验过程中,与其他组相比,0.07%粉状迷迭香提取物+0.07%油状迷迭香提取物+0.01% V_C表现出最佳的协同效应,此组样品过氧化值由第0 d的1.38 meq/kg仅增加到第24 d的1.65 meq/kg,酸值由第0 d的0.93 mg KOH/g仅增加到第24 d 1.03 mg KOH/g;和对照组相比,其p-茴香胺值,硫代巴比妥酸值在贮藏期内显著降低(p<0.05),表明该组复合抗氧化剂的协同抗氧化效果较优。风味测定结果表明,复合抗氧化剂不能改变风味化合物中的主要物质的组成,但会部分增加或减少某些风味物质的含量。添加最优复合抗氧化剂后氧化的花生油稍有天然提取物的风味,与吡啶类化合物,呋喃类化合物的含量变化有关。     

Flour and anthocyanin extracts of jaboticaba skins used as a natural dye in yogurt

This study used the flour and anthocyanin extracts from jaboticaba skins as a dye in yogurt. Jaboticaba skins were lyophilised and ground. Yogurt that was made in the conventional fashion was treated with the addition of flour from jaboticaba skins in the concentrations of 0.1%, 0.5%, 1.0%, 1.5% and 2.0% or with the anthocyanin extract in the concentrations of 0.5%, 1.0%, 1.5%, 2.0% and 2.5%, with and without tannic acid; the yogurt samples were stored for 45 days. In general, the results of the acceptance test of the yogurt samples ranged between like slightly and like moderately. The highest scores received by the anthocyanin extract (like slightly) were obtained for the concentrations of 0.5–1.5%. The colour retention for all yogurt samples was above 70%. The average half‐life was greater than 2500 h, considered high. We conclude that the use of jaboticaba skins as additives to yogurt can be an alternative to add value to jaboticaba.     

甜酒曲糖化制备花生粕糖化液的研究

为寻求一种新型降解花生粕中淀粉的途径,本研究采用甜酒曲对花生粕进行糖化,并在底物料液比、糖化温度、底物pH、甜酒曲添加量的单因素试验的基础上,利用响应面试验设计优化了糖化条件。并分别测定了优化后所得糖液的色度、还原性糖浓度、总酸含量、总多肽、总多酚、蛋白质含量、总游离氨基酸、DPPH的清除率等。通过响应面分析得到花生粕最佳糖化条件为：温度30℃、底物pH5.2、甜酒曲添加量0.6%、底物料液比1:15。在此条件下甜酒曲对花生粕的糖化率达91.2%,所得糖化液颜色金黄诱人,且口感良好,其色度为0.753、还原糖浓度为18.24g/L,总酸含量为1.85g/kg,多肽含量为286mg/L,总多酚含量为421ug/L、蛋白质含量为11g/L、总游离氨基酸含量为260mg/L。将其稀释20倍后,测定其对DPPH的清除率为 77.8%,表明该糖化液具有一定的营养价值。     

用于面包制作的葡萄天然酵母发酵工艺优化

以葡萄干为发酵原料,研究不同发酵工艺参数对葡萄天然酵母发酵力的影响,为用于面包中的天然酵母发酵优化工艺提供一定的试验数据。以单因素试验为基础,采用响应面分析法对发酵工艺参数进行优化,结果表明:最优发酵条件为培养温度26℃,培养时间4d,葡萄干与白砂糖配比101。该条件下,天然酵母发酵力为0.077 9,与市售的即发干酵母的发酵力较为接近,可代替其用于面包的制作中。     

花生红衣总多酚抑制酪氨酸酶活性和抗氧化作用研究

通过单因素实验和正交实验,确定了闪式提取花生红衣总多酚的最佳工艺条件;并研究了花生红衣总多酚对酪氨酸酶的抑制作用及清除DPPH自由基的能力。闪式提取最佳工艺条件为:乙醇浓度80%,料液比1∶25(g/mL),提取电压90V,提取3次,每次2min,该条件下,花生红衣总多酚的平均提取率为96.94%;花生红衣总多酚对酪氨酸酶的抑制率达到50%(IC50)时所需的花生红衣总多酚的质量浓度为0.451mg/mL,最高抑制率可达89.65%;并且花生红衣总多酚清除DPPH自由基的能力大于VC,稍弱于没食子酸。      

Improving skin function with CM-glucan, a biological response modifier from yeast

Preparations from yeast have been used for a long time for cosmetic and pharmaceutical purposes. Studies have identified glucan from the cell wall of baker's yeast as an immunologically active agent. Glucan is a poly beta-( 1-3)-linked glucopyranose of high molecular weight and belongs to the class of compounds known as biological response modifiers. Glucan preparations are involved in the activation of the body's natural defence mechanisms and in the acceleration of the skin's wound healing processes. In the skin, Langerhans' cells and keratinocytes are the immunologically competent cells. Recent studies indicate that UV irradiation can deplete the number and viability of these cells (immunosuppression). The use of non-specific immune-stimulators, such as glucan, is a new approach for improving the function of stressed skin. We have developed a process to modify pure glucan from baker's yeast to carboxymethyl glucan (CM-glucan), a water soluble product suitable for topical formulations. The functional properties of this new compound have been investigated in vitro and in vivo. Cell culture experiments showed that CM-glucan protects skin cells against the depletion of antioxidant molecules upon UV-A irradiation and promotes the growth of keratinocytes. In placebo controlled studies with healthy volunteers, the pretreatment of skin with CM-glucan offered substantial protection against skin damage caused by a detergent challenge or UV-A irradiation. In addition, CM-glucan enhanced the renewal rate of the stratum corneum.     

柿果醋自然发酵下优势酵母菌的分离鉴定

以自然发酵柿子原浆果醋的发酵醪为试验材料,对其中的优势酵母菌进行分离,再经过初筛、复筛,依据发酵能力以及产香性能得到一株优势酵母菌。对该优势菌株从形态学观察和生理生化试验进行鉴定,结果为马克斯克鲁维酵母（Kluyveromyces marx-ianus）,属于克鲁维酵母属,命名为Kluyveromyces marxianus JM2。     

酵母抽提物对原酿黄豆酱呈味物质的影响研究

通过自动电位滴定、高效凝胶过滤色谱等方法研究了1%添加量的3款纯品型和3款5'肌苷酸二钠＋5'鸟苷酸二钠（I+G）型酵母抽提物（YE）对原酿黄豆酱中游离氨基酸、5'-呈味核苷酸、小分子肽等呈味物质和感官评价的影响。结果表明,1%添加量的纯品型酵母抽提物YE3、I+G型YE4以及I+G型YE5分别能明显提升原酿黄豆酱的丙氨酸、谷氨酸、5'-呈味核苷酸等鲜味物质的含量,提升效果分别为90%、27%、63倍;纯品型YE2可使分子质量为400～1 000 Da的小分子肽提升64%,并在口感上对应的体现出提鲜、淡咸、抑苦、增厚和协调整体口感等应用效果,应用效果较好的是3款I+G型酵母抽提物。     

花生红衣补血口服液改善大鼠缺铁性贫血 作用的研究

随着我国功能性食品行业的进步与发展,改善营养性贫血的产品也日益增多,但是以花生红衣作为原料的补血口服液保健品还尚未见报。本研究的目的是为了验证花生红衣补血口服液对改善缺铁性贫血的作用效果。用低铁饲料饲喂大鼠5周后,建立缺铁性贫血大鼠模型,随机分成低铁对照组和花生红衣补血口服液的低、中、高剂量实验组,观察每组大鼠体重、血红蛋白（Hb）和红细胞游离原卟啉（FEP）含量的变化。实验结果表明：灌胃花生红衣补血口服液低、中、高剂量实验组大鼠的体重和Hb含量均显著高于低铁对照组（P＜0.05）,FEP含量显著低于低铁对照组（P＜0.05）。本实验的结论是：花生红衣补血口服液具有改善缺铁性贫血的功能。