Fatty acid profile and glycerol concentration in cachaças aged in different wood barrels

The objective of this study was to evaluate the fatty acid profile and glycerol concentration in cachaças aged for 3 years in barrels made from different types of tropical woods and European oak. Glycerol gives body to spirits, whereas the fatty acid profile influences the spirit sensory characteristics. The concentration of these compounds in aged spirits depends on the wood composition. Tropical wood barrels made from amendoim (Pterogyne nitens Tul), araruva (Centrolobium tomentosum), cabreúva (Myrocarpus frondosus), cerejeira (Amburana cearensis), grápia (Apuleia leiocarpa), ipê roxo (Tabebuia heptaphylla), jequitibá (Cariniana estrellensis), jequitibá rosa (Cariniana legalis) and pereira (Platycyamus regnellii), as well as European oak (Quercus petraea), were used in this study. Glycerol concentrations in aged cachaças were measured using colorimetric methods, and fatty acid profiles were determined by GC‐MS analysis. The main fatty acids found were propanoic (C3:0), butanoic (C4:0), pentanoic (C5:0), octanoic (C8:0), decanoic (C10:0), dodecanoic (C12:0), hexadecanoic (C16:0), octadecanoic (C18:0) and octadecenoic (C18:1⁹) acids. Araruva barrels stood out as the major supplier of C4:0 and cabreúva barrels provided greater amounts of C18:0 to cachaça. Carvalho and araruva barrels conferred more complete fatty acid profiles and higher concentrations of glycerol. Copyright © 2016 The Institute of Brewing & Distilling     

杭白菊不同溶剂提取物的抗氧化活性研究

本研究采用水、80%乙醇、乙酸乙酯和石油醚4种不同极性的溶剂对杭白菊进行提取,以总还原能力、DPPH·、O-2·和·OH清除率为指标,研究了所得4种杭白菊粗提物的抗氧化能力。结果表明:总还原能力由强到弱依次为80%乙醇提取物>乙酸乙酯提取物>水提物>石油醚提取物;80%乙醇提取物清除自由基的能力最强,其清除DPPH·、O-2·、·OH的IC50值分别为0.33、0.44、0.34 mg/m L;石油醚提取物清除DPPH·、O-2·、·OH的能力最弱,清除DPPH·和·OH的能力均小于50%,清除O-2·的IC50值为0.85 mg/m L;水提物清除DPPH·、O-2·和·OH的IC50值分别为0.57、0.69、0.56 mg/m L;乙酸乙酯提取物清除·OH的能力小于50%,清除DPPH·、O-2·的IC50值分别为0.56、0.62 mg/m L。因此,不同杭白菊提取物均具有抗氧化作用,且抗氧化能力与其提取溶剂有关。      

比较研究新疆小茴香不同溶剂提取物的抗氧化活性

研究新疆小茴香4种不同溶剂萃取物的抗氧化活性.采用DPPH、ABTS和还原能力法评估不同萃取物的抗氧化活性,并测定了萃取物中的总酚和总黄酮的含量.结果表明,各样品具有不同程度的抗氧化能力,甲醇萃取物的抗氧化活性显著强于其他溶剂萃取物.小茴香抗氧化活性的主要物质为酚类化合物,与其总黄酮的含量并没有明显的关联.     

Aging marker profile in cachaça is influenced by toasted oak chips

Cachaça is the most important distilled spirit in Brazil and the fourth most consumed in the world. Aging is not mandatory for cachaça. When aging is carried out, casks generally do not undergo the final wood toasting. However the level of thermal degradation of wood influences the formation of new chemical compounds, which are released during the aging process and improve the quality of the spirit. The objective of this study was to verify the influence of origin of wood and toasting intensity of oak chips on the profile of aging markers in cachaça. Staves of oak wood from the forests of Allier, Vosges and Nièvre (France) were milled and screened at 9 mesh. The chips underwent light, medium and heavy toasting. The toasted chips were added to cachaça (1 g/L) and kept in a closed system at room temperature, without agitation, for 15 days. The aging congeners (gallic acid, 5‐hydroxymethylfurfural, furfural, vanillin, vanillic acid, syringaldehyde, sinapaldehyde, syringic acid and coniferaldehyde) were analysed using HPLC. The increase in toasting intensity enhanced the content of the aging markers in cachaça, especially syringic acid, vanillin, syringaldehyde, coniferaldehyde and sinapaldehyde. The generation of aging marker compounds was influenced only by the toasting intensity and not by the origin of the oak wood. Copyright © 2015 The Institute of Brewing & Distilling     

核桃仁皮不同极性提取物的体外抗氧化活性分析

采用乙酸乙酯、正丁醇、氯仿、石油醚对核桃仁皮多酚进行提取,通过清除DPPH自由基、OH自由基、ABTS自由基法与铁离子还原能力初步评价其体外抗氧化活性。结果表明,不同极性溶剂对核桃仁皮多酚提取能力为乙酸乙酯>正丁醇>氯仿>石油醚;乙酸乙酯提取物具有最强的DPPH自由基清除能力和ABTS自由基清除能力,其IC₅₀值分别为5.004和29.654 μg/mL,其次为正丁醇(9.596、23.681 μg/mL)、氯仿提取物(62.719、144.475 μg/mL)以及石油醚提取物(48.316、146.424 μg/mL);正丁醇提取物具有最强的OH自由基清除能力,其IC₅₀值为393.578 μg/mL,其次为乙酸乙酯(510.186 μg/mL)、氯仿提取物(627.003 μg/mL)与石油醚提取物(840.315 μg/mL);在铁离子还原能力实验中,当样品浓度均为100 μg/mL时,各提取物的吸光度为乙酸乙酯(0.821)>正丁醇(0.509)>氯仿(0.406)>石油醚(0.142)。总之,不同极性提取物其抗氧化能力有差异,依次为乙酸乙酯>正丁醇>氯仿>石油醚,且与质量浓度呈正相关。     

鸡枞菌不同溶剂提取物成分分析及抗氧化作用研究

利用分光光度法和液相色谱法测定鸡枞菌8种不同极性溶剂提取物中总黄酮、总酚、麦角甾醇及腺苷含量;通过清除DPPH·、ABTS~+·、羟自由基以及总抗氧化和总还原能力来比较不同极性溶剂提取物的抗氧化活性。结果表明:不同极性溶剂提取物得率最高的为蒸馏水;蒸馏水提取物中还含有最高的总酚和腺苷;正乙烷提取物中总黄酮含量最高;甲醇提取物中麦角甾醇含量最高。蒸馏水和甲醇提取物具有更好的清除自由基效果;溶剂极性越大,抗氧化活性越强;综合抗氧化能力与总酚含量呈正相关。鸡枞菌中含有多种生物活性成分,具有很好的抗氧化作用。     

水溶性辣椒皮渣提取物抗氧化性的研究

对提取过辣椒红素的辣椒皮渣采用直接用水浸提的方法得到水溶性提取物,从还原能力,抗脂质体氧化及对Fenton体系产生的羟自由基和NO2-·自由基的清除效果等方面对水溶性辣椒皮渣提取物的抗氧化活性进行了试验研究和评价。结果表明:水溶性辣椒皮渣提取物具有强还原能力,对脂质体氧化、Fenton反应产生的羟自由基和NO2-·自由基均具有抑制作用或消除作用,并随其浓度增高水溶性辣椒皮渣提取物的抗氧化活性呈现出增强的趋势,这表明提取辣椒红色素后的辣椒皮渣中仍含有大量的抗氧化物质,具有很高的利用价值。     

Profile of antioxidant and antibacterial activities of different solvent extracts from Rabdosia rubescens

The objective of this work was to investigate the antioxidant and antibacterial activities of different extracts from Rabdosia rubescens and to further evaluate the antibacterial mechanism of extracts. The results showed that 80% acetone extracts had the highest contents of total polyphenols (8.09 mg GAE g^?1) and flavonoids (5.69 mg RE g^?1) and exhibited the strongest antioxidant activities, followed by 80% methanol and 80% ethanol, and the lowest for hexane extracts. Others except for hexane extracts showed different antibacterial activities against Gram‐positive strains, while no inhibitory effects were found on tested Gram‐negative bacterial strains. Among these extracts, 80% acetone and ethanol extracts had relatively higher antibacterial activities with the lowest minimum inhibitory concentration and minimum bactericidal concentration values of 5 and 10 mg mL^?1. The antibacterial mechanism of ethanol extracts against Staphylococcus aureus might be described as it disrupts cell wall, increases cell membrane permeability and then leads to the leakage of cell constituents.     

Chemical and microbiological quality of sugar cane juice influences the concentration of ethyl carbamate and volatile congeners in cachaça

The aim of this study was to assess the influence of heat treatment of sugar cane juice, supplementation with urea and double distillation on the concentration of volatile congeners (acetic aldehyde, ethyl acetate, n‐propyl, isobutyl and isoamyl alcohols and acetic acid) and contaminants (methanol, 1‐propyl and 2‐butyl alcohols, copper, and ethyl carbamate) in cachaça. Samples of fresh sugar cane juice, sugar cane juice submitted to heat treatment and contaminated sugar cane juice were supplemented (or not) with urea and fermented. The washes so obtained underwent single and double distillation. Supplementation with urea stimulated ethyl carbamate formation. The distilled products that originated from contaminated worts presented higher concentration of acetic acid and ethyl carbamate. Double distillation reduced the concentration of contaminants. The best quality pot still cachaça was obtained employing heat treatment of sugar cane juice, nonsupplementation with urea and double distillation. Copyright © 2015 The Institute of Brewing & Distilling     

铁苋菜不同极性萃取物的抗氧化及抑菌活性研究

采用1,1-二苯基-2-三硝基苯肼(DPPH)法、β-胡萝卜素漂白法和清除一氧化氮自由基(NO)法来测定不同极性铁苋菜萃取物的抗氧化活性;通过微孔比浊法比较铁苋菜萃取物对3种革兰氏阴性细菌(大肠杆菌、铜绿假单胞菌和幽门螺杆菌)和4种革兰氏阳性细菌(表皮葡萄球菌、枯草芽孢杆菌、藤黄微球菌和金黄色葡萄球菌)的抑菌效果。结果表明,铁苋菜不同极性萃取物均有较好的清除DPPH、NO自由基和抑制β-胡萝卜素漂白的效果,浓度为2.0mg/mL时,正丁醇萃取物清除DPPH自由基和抑制β-胡萝卜素漂白能力最佳,DPPH自由基清除率为94.60%,β-胡萝卜素抑制率为83.15%,乙酸乙酯萃取物清除NO自由基能力最强,清除率为82.72%。抑菌试验结果显示,铁苋菜各萃取物均有较好抑菌效果,对革兰氏阳性菌抑菌效果优于革兰氏阴性菌,其中石油醚萃取物对大肠杆菌、表皮葡萄球菌和金黄色葡萄球菌抑制作用最佳,MIC值分别为0.625,0.315,1.250mg/mL。铁苋菜萃取物具有较好的抗氧化及抑菌效果。     

黑豆提取物抗氧化性的研究

以抗坏血酸为参照物,对黑豆提取物的抗氧化性进行研究,结果表明,黑豆提取物具有比较强的DPPH·自由基清除能力、超氧阴离子自由基清除能力、抗脂质体氧化能力以及还原能力。因此,黑豆提取物具有可以作为天然的抗氧化剂应用于食品开发的潜质。     

拐枣不同提取物的体外抗氧化作用

对拐枣子、拐枣和拐枣枝体积分数为80%的乙醇溶液浸提物抗氧化性进行比较,再选取拐枣为试验材料,经体积分数为80%的乙醇浸提浸膏分别用石油醚、乙酸乙酯、正丁醇、甲醇萃取,福林酚法测定不同极性部位多酚含量,通过测定DPPH自由基、ABTS自由基的清除率,研究拐枣萃取物的抗氧化作用。结果表明,拐枣对DPPH和ABTS自由基清除率分别为87.07%和95.67%,其抗氧化性高于拐枣子及拐枣枝;拐枣乙醇提取物浸膏不同极性萃取物中,乙酸乙酯萃取物的抗氧化能力最强,其多酚含量为202.8 mg/g,对DPPH和ABTS自由基清除作用的IC50分别为182 μg/mL和60 μg/mL,最大清除效率分别为94.0%和98.57%。试验表明拐枣具有较好的抗氧化能力,具有开发利用的价值。     

洋葱黄酮的提取条件及抗氧化活性的研究

为研究超声波辅助乙醇提取洋葱黄酮最佳工艺和抗氧化活性。采用正交实验,研究乙醇体积分数、超声时间、浸提时间和料液比对洋葱黄酮提取量的影响,测定了在最优条件下提取洋葱黄酮的还原力和对羟自由基的清除率。结果表明,洋葱黄酮最佳提取工艺条件为乙醇浓度70%,超声波处理时间5min,浸提时间1.5h,料液比1∶15(m∶V),该条件下洋葱黄酮的提取量为40.17mg/g。0.5mg/mL洋葱黄酮与0.5mg/mLVC还原力相等;洋葱黄酮对羟自由基的清除率随着溶液浓度(0～1.2mg/mL)的增加而增大,浓度为1.2mg/mL的黄酮溶液清除率为32.42%。实验表明洋葱黄酮提取物具有较强的抗氧化活性,可作为抗氧化剂或为研制功能食品提供资源。      

红树莓不同溶剂提取物抗氧化活性

以红树莓鲜果为原料,采用体外抗氧化方法研究不同溶剂提取对红树莓抗氧化活性的影响。分别以水、25%乙醇、50%乙醇、75%乙醇、100%乙醇、乙酸乙酯、正丁醇为提取溶剂,测定提取物中总酚、黄酮、原花青素和花色苷含量;研究提取物体外抗氧化活性的差异;对活性物质含量与抗氧化能力进行相关性分析。结果表明,50%乙醇粗提物的总酚、黄酮、原花青素和花色苷含量均最高,分别为257.19、10.48、406.45、22.47 mg/100 g;7种不同红树莓提取物中50%乙醇提取物的总还原力与V_C相近,50%和75%乙醇提取物对DPPH·清除能力强于V_C,7种溶剂提取物对羟基自由基清除能力均弱于V_C;红树莓7种溶剂提取物中总酚与对DPPH·的清除率及总还原能力的相关性较大。比较发现,50%~75%的乙醇水溶液能够更好的溶出红树莓中的活性成分,而具有更强的抗氧化活性。      

薄荷不同溶剂提取物抗氧化活性的研究

采用1,1-二苯基-2-三硝基苯肼（DPPH）、2,2’-联氮基双（3-乙基苯并噻唑啉-6-磺酸）二铵盐（ABTS）、Fe+还原法（FRAP）三种抗氧化模型对薄荷的水、甲醇、70%乙醇、正丁醇、乙酸乙酯五种提取物进行抗氧化活性评价,同时分析抗氧化活性与总酚和总黄酮含量的关系。结果表明,薄荷不同提取物均表现出良好的抗氧化活性,其抗氧化活性与多酚含量呈极显著相关,与黄酮含量相关性较小。其中,水提物对DPPH自由基清除率最高,EC50值为（0.53±0.04）mg/mL;甲醇提取物对ABTS自由基清除率最高,EC50值为（1.57±0.03）mg/mL;乙酸乙酯提取物的FRAP值最高为（4.73±0.03）mmol/g;水提物中总酚含量最高为（58.81±3.10）mg/g,甲醇提取物中总黄酮含量较高为（162.95±1.91）mg/g。      

龙眼核提取物的体外抗氧化及抑菌活性研究

探讨龙眼核中不同极性部位的体外抗氧化和抑菌活性,并筛选其有效部位。以Folin-Ciocalteu比色法测定龙眼核95%乙醇提取物中4种不同极性萃取物的总酚含量,并利用ABTS法、DPPH法、邻苯三酚自氧化法、邻二氮菲—Fe2+氧化法测定评价各萃取物的抗氧化活性,同时采用牛津杯法测定比较4种萃取物的抑菌活性。结果表明:乙酸乙酯萃取物的总酚含量最高,达到(693.51±9.52)mg/g;在不同的自由基体系中,4种萃取物均对·O-2的清除作用最弱,但对清除ABTS·+、DPPH·、·OH均表现出较强的效果,龙眼核各萃取物抗氧化能力的结果为乙酸乙酯萃取物氯仿萃取物正丁醇萃取物水层剩余物;除水层对沙门氏菌和大肠杆菌均无明显抑制作用外,4种萃取物对沙门氏菌、大肠杆菌、金黄色葡萄球菌均具有不同强度的抑制作用,其中乙酸乙酯层的抑菌活性最为突出。由结果可推断乙酸乙酯萃取物含有丰富的多酚类物质,可作为一种天然的抗氧化剂和抑菌剂,具有很大的药用价值和应用前景。     

油茶籽壳提取物抗氧化及抗癌活性研究

目的:观察油茶籽壳不同溶剂提取物（乙酸乙酯、正丁醇、氯仿、水）体外抗氧化和抗肿瘤活性。方法:采用Folin-Ciocalteu和三氯化铝方法检测总酚及总黄酮含量;采用DPPH法和邻二氮菲-Fe2+氧化法测抗氧化活性;采用CCK-8法测细胞的活性。结果:油茶籽壳乙酸乙酯提取物、正丁醇提取物、氯仿提取物、水提取物总酚含量分别为79.25±4.552、51.81±3.651、2.762±0.523、19.73±1.191mg/g;总黄酮含量分别为26.73±0.613、15.63±1.126、13.16±0.672、5.734±0.761mg/g;油茶籽壳乙酸乙酯提取物、正丁醇提取物、氯仿提取物、水提取物在15.625²50μg/m L范围内体外抗氧化活性均具有剂量依赖性;对Hep G2细胞增殖抑制作用在62.5²50μg/m L范围内均具有剂量依赖性。结论:体外抗氧化活性和抗肿瘤活性强弱均表现为乙酸乙酯提取物>正丁醇提取物>水提取物>氯仿提取物,其中乙酸乙酯是油茶籽壳提取的有效溶剂。