Extraction of Lignan Compounds from Roasted Sesame Oil and their Effects on the Autoxidation of Methyl Linoleate

ABSTRACT:  Lignan compounds were extracted from roasted sesame oil and their effects on the autoxidation of methyl linoleate (ML) were studied. Lignan compounds extracted from roasted sesame oil, sesamol, sesamin, and sesamolin, were added to ML, which was then oxidized at 60 ^oC for 18 h in the dark. Alpha-tocopherol was separately added to ML for a reference antioxidant. Degree of ML oxidation was monitored by conjugated dienoic acid (CDA) contents and p -anisidine value (PAV) by AOCS methods, and ML retention by gas chromatography. CDA contents and PAV of samples increased with the oxidation time at 60 ^oC in the dark, and ML decreased. Sesamol-, sesamin-, or sesamolin-added samples showed lower CDA contents, PAV, and ML loss than the samples without lignans during oxidation in the dark, which indicated that lignan compounds lowered the ML autoxidation. The antioxidant activity of sesamol was significantly higher ( P < 0.05) than that of sesamin, sesamolin, or α-tocopherol. Lignan compounds added to ML were degraded during the autoxidation of ML, and the degradation rate was higher in sesamol- than in sesamin-, or sesamolin-added ML, but was lower than in tocopherol-added samples. As the lignan compounds concentration in ML increased, the degradation rate of lignans decreased, and the inhibition of the ML autoxidation by lignan compounds increased. The results strongly suggested that the autoxidative stability of ML could be improved by the addition of sesamol, sesamin, or sesamolin extracted from the roasted sesame oil.     

Wine industry residue as antioxidant in cooked chicken meat

The effectiveness of grape extracts as food ingredient has been tested in various systems. The objective of this study was to evaluate the efficiency of four concentrations of residues of the wine industry in delaying lipid oxidation in processed chicken meat stored under refrigeration. The development of oxidation during the 14‐day storage was evaluated through the thiobarbituric acid reactive substances method (TBAS). The analyses of phenolic compounds and antioxidant activity were performed in grape residue extracts through DPPH (1,1‐difenil‐2‐picrilidrazil) method, lipid peroxidation inhibition and Rancimat. The profile of polyphenols was determined using reversed‐phase high‐performance liquid chromatography. Isabel grape extract (IGE) and Niagara grape extract (NGE) showed significant content of phenolic compounds. NGE and IGE had high antioxidant activity. The addition of grape extracts significantly increased the oxidative stability of processed and cooked chicken meat during the storage time. The extracts from both grape varieties when applied in concentrations of 40 and 60 mg of GAE, presented results similar to that of Butyl hydroxy toluene (BHT).     

In vitro and in vivo antioxidant activity of musts and skin extracts from off-vine dried Vitis vinifera cv. “Tempranillo” grapes

The phenolic composition and antioxidant activity of musts and skin extracts from Tempranillo grapes dried for variable lengths of times were examined here. Both were found to increase in the grape must with increasing drying time, but the opposite trend was observed in the skin extracts. The antioxidant activity of the must and skin was largely due to anthocyanins. Also, the anthocyanins fraction exhibited the highest antioxidant activity per gram of phenolic compound in the musts and skin extracts at the end of the drying process, polymeric pigments and high-molecular-weight procyanidins were also prominent in this respect. In vivo antioxidant activity in terms of protein oxidation and survival of Saccharomyces cerevisiae cells previously incubated with 10 μg/mL of polyphenols from the musts and skins and exposed to hydrogen peroxide was also measured. Both extracts exerted a protective effect against oxidative stress, the effect increasing with increasing dehydration time and being somewhat higher for skin than for must. Thus, must and skin from dehydrated grapes possess antioxidant properties, which allow the latter, a by-product of sweet wine, to be used as a natural source of antioxidants.     

Antioxidant protection of white grape pomace on restructured fish products during frozen storage

White grape antioxidant dietary fibre (WGDF) was obtained from white grape (Vitis vinifera, var. Airén) pomace from wine production. The antioxidant capacity of WGDF was determined in minced fish muscle (MFM) during frozen storage. Concentrations of 0, 2, and 4% WGDF ((0-WGDF), (2-WGDF), and (4-WGDF) respectively) were added to MFM samples. Analyses were carried out immediately after preparation of samples and over 6 months of storage at −20 °C. WGDF was characterized in terms of dietary fibre (DF) (insoluble and soluble), total polyphenols and antioxidant capacity, and multifunctional antioxidant assays were done on all the MFM samples. The addition of white grape DF considerably delayed lipid oxidation in minced horse mackerel muscle during the frozen storage. Vacuum-packing the sample with 2% WGDF significantly enhanced the antioxidant properties of WGDF.     

Effects of Sesame Oil Addition to Soybean Oil During Frying on the Lipid Oxidative Stability and Antioxidants Contents of the Fried Products During Storage in the Dark

ABSTRACT: Effects of sesame oil addition to soybean oil during frying on the lipid oxidative stability and antioxidants contents of fried products during storage in the dark were studied. Flour dough pieces (2 cm × 2 cm × 0.1 cm) were fried at 160 °C for 1 min in sesame oil-added soybean oil. Concentrations of sesame oil in the frying oil were 0%, 10%, and 20% by volume. Fried products were put into a glass bottle, and the bottles were tightly sealed and stored at 60 °C in the dark for 18 d. Lipid oxidation of fried products was determined by fatty acid composition changes and conjugated dienoic acid (CDA) and p -anisidine (PA) values. Tocopherols and lignan compounds in the fried products were determined by high-performance liquid chromatography. Relative content of linolenic acid decreased, and CDA and PA values increased during storage of the fried products in the dark. Fatty acid composition change and CDA and PA values during storage were lower in the products fried in sesame oil-added soybean oil than in the products fried in soybean oil without sesame oil. The results clearly showed that addition of roasted sesame oil to soybean oil at 10% and 20% during frying decreased the lipid oxidation of fried products during storage in the dark for 18 d by extension of induction period and decrease in decomposition of oxidized lipids. Fried products contained 134 to 267 ppm tocopherols and 0 to 148 ppm lignans before storage; however, their contents decreased during storage in the dark. Lignan compounds were more stable than tocopherols, and the rate of tocopherols degradation was lower in the products fried in sesame oil-added soybean oil than in the products fried in soybean oil without sesame oil, which could be because of protection of tocopherols from degradation by lignan compounds.     

13种植物多酚提取物抗氧化活性分析及其对冻藏未漂洗鱼糜品质的影响研究

目的 分析13种植物多酚提取物抗氧化活性并研究其对冻藏未漂洗鱼糜品质的影响。方法 比较分析了石榴、芝麻、蓝莓、姜黄、迷迭香、薄荷、葡萄、橄榄、草莓、马鞭草、茶籽、燕麦、莲子皮13种植物多酚提取物的抗氧化活性及对冻藏未漂洗鱼糜脂质氧化、凝胶强度的影响。结果 迷迭香多酚提取物对羟自由基清除率最高,达到87.56%±0.28%;石榴多酚提取物对超氧阴离子的清除率最高,为86.11%±0.72%;葡萄多酚对脂氧酶抑制率最高,为89.04%±2.01%。新鲜鱼糜丙二醛含量为(0.18±0.01)mg/kg,冻藏3d后,急剧增加至(0.54±0.04) mg/kg;葡萄多酚抑制鱼糜氧化效果最好,鱼糜丙二醛含量为(0.23±0.02) mg/kg。添加姜黄多酚的冻藏未漂洗鱼糜冻融后的凝胶强度最高,为1049.85 g·mm。葡萄多酚和姜黄多酚比例为1:1时,未漂洗鱼糜丙二醛含量最低,为(0.21±0.02) mg/kg;凝胶强度最高,为(1249.97±13.31) g·mm。结论 葡萄多酚和姜黄多酚比例为1:1的多酚混合物是较好的冻藏未漂洗鱼糜保鲜剂。     

Impact of Pressing Conditions on the Phenolic Composition,Radical Scavenging Activity and Glutathione Content of Brazilian <Emphasis Type="Italic">Vitis vinifera</Emphasis> White Wines and Evolution During Bottle Ageing

The pre-fermentation techniques applied during the production of white wine, such as skin maceration or grape pressing, can directly affect the quality of the final product. There is a constant search for methods that can enhance the sensorial characteristics, such as varietal aromas, and phenolic composition of white wines. The aim of this study was to investigate the effect of different pressing conditions on the phenolic composition, antioxidant activity and glutathione content of white musts and wines produced in southern Brazil and to evaluate these characteristics during bottle ageing. By applying different pressures, three fractions of musts were obtained: free-run must, light pressed must and heavy pressed must. The musts and their corresponding wines were analysed by spectrophotometric and chromatographic assays. Pressing positively affected the chemical composition of the musts and wines, and the wines produced with pressed fractions of the musts presented higher polyphenol content and radical scavenging power. The main phenolic compounds affected by the pressing conditions were caftaric acid, catechin and epicatechin. During bottle ageing, an increase in certain individual phenolic compounds could be observed by liquid chromatography. Samples produced with heavy pressed musts presented a higher browning index. Furthermore, the application of pressure to the grape musts during winemaking increased the contents of total glutathione by factors of up to 22 and 15 for light pressed and heavy pressed musts, respectively. After 8 months of bottle ageing, the glutathione content decreased in all samples.     

Antioxidant activity of different phenolics fractions isolated in must from Pedro Ximenez grapes at different stages of the off-vine drying process

The evolution of total phenolics, flavonoids and flavonols in the white grapes of Pedro Ximénez were determined during the off-vine drying process. Phenolics compounds determined, browning index and total antioxidant activity increased during the off-vine drying process. The analysis by gel filtration chromatography showed that compounds of high molecular weight are formed during the off-vine process and are partially responsible for the antioxidant activity and browning of grapes. Musts were separated by solid phase extraction in four fractions (I–IV) and the phenolics and antioxidant activity determined. Fraction III containing catechins and procyanidins, and fraction IV containing polymeric procyanidins were greatly enhanced during the off-vine drying process. Lastly, ethanolic extracts from grape pomaces at different drying stages were fractionated and analysed. The antioxidant activity showed similar values to those obtained in musts at the end of the drying process; however total phenolics and the browning index showed a 30% and 50% reduction, respectively, in comparison to those observed in the corresponding musts. This indicates that the ethanolic extracts could be used as a source of phenolic compounds without enhancing browning and as a way to increase the antioxidant activity of wines from dried grapes.     

亚麻木脂素抗氧化性能的研究及应用现状

木脂素是由苯丙素单体（C6-C3）氧化聚合而成的化合物。亚麻木脂素具有降低血清胆固醇水平、延缓2型糖尿病进程、预防乳腺癌、前列腺癌及结肠癌等功能,在生物体内和生物体外均有很好的抗氧化特性。综述了亚麻木脂素的种类及结构,亚麻木脂素在生物体内和生物体外的抗氧化活性,亚麻木脂素抗氧化性能的应用现状3个方面的研究内容,为进一步丰富亚麻木脂素抗氧化机理的探究及高效开发利用亚麻木脂素抗氧化性能提供参考。     

Effect of grape antioxidant dietary fibre on the prevention of lipid oxidation in minced fish: Evaluation by different methodologies

The effect of grape antioxidant dietary fibre (GADF) addition to minced fish muscle (MFM) on lipid stability during frozen storage (6 months) was studied. Concentrations of 0%, 2%, and 4% GADF were added to MFM samples. Analyses were carried out immediately after preparation of samples and during and after storage at −20 °C. GADF was characterized in terms of dietary fibre, total polyphenols and antioxidant capacity, and multifunctional antioxidant assays were carried out on all the MFM samples. The addition of red grape fibre considerably delayed lipid oxidation in minced horse mackerel muscle during the first 3 months of frozen storage.     

盐诱导乙醇水体系萃取分离葡萄皮中原花青素

采用盐诱导乙醇水体系萃取分离葡萄皮中原花青素,利用单因素试验和正交试验研究了盐的种类和加入量、乙醇体积分数、样品加入量、温度对原花青素萃取效果的影响。并且以1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除能力、还原Fe3+能力、羟自由基清除能力分析葡萄皮中原花青素的抗氧化活性。结果表明,乙醇体积分数为50%,料液比为1∶15(g∶mL)制备原花青素粗提液;然后向15 mL粗提液中加入3.6 g Na2HPO4,在30 ℃条件下充分混匀分相后,葡萄皮中原花青素萃取率和分配系数分别为85.51%和2.48。抗氧化实验结果表明,葡萄皮中原花青素有一定抗氧化活性,萃取后原花青素比粗提液中原花青素的抗氧化能力强。     

三种天然抗氧化剂复合对冻藏牛肉丸抗氧化效果的研究

天然抗氧化剂来源天然、安全。本文研究了茶多酚、葡萄籽提取物、Vc三种天然抗氧化剂对冻藏牛肉丸的抗氧化效果,以添加浓度为0.02%BHA的处理组为对照组,以不添加任何抗氧化剂的处理组为空白。通过测定牛肉丸冻藏期间过氧化物值(POV)、硫代巴比妥酸值(TBARS)、羰基价等指标的变化,确定了三种天然抗氧化剂的最适添加比例;为了研究茶多酚、葡萄籽提取物、Vc三种天然抗氧化剂协同对牛肉丸脂肪氧化和品质特性的抗氧化效果,采用L_9(3~3)正交实验进行了三种天然抗氧化剂复合配比的优化,以TBARS和感官评定为测试值。研究表明,三种天然抗氧化剂最适配比为:茶多酚0.5%、Vc 0.03%、葡萄籽提取物0.05%。本研究开发的天然复合抗氧化剂对于牛肉丸冻藏期间的脂肪氧化及品质的改善均有很理想的效果,具有潜在的应用价值。     

贮藏条件对赤霞珠葡萄汁活性成分含量及抗氧化能力的影响

以赤霞珠葡萄汁为试验材料,研究不同条件下葡萄汁的活性成分含量和抗氧化能力随贮藏时间的变化,探讨花色苷含量与抗氧化能力的相关性。结果表明,不同条件下的葡萄汁活性成分和抗氧化能力随贮藏时间的增加均呈下降的趋势,4℃下贮藏的活性成分损失率显著低于10、25℃组(p<0.05),避光下贮藏的活性成分损失率显著低于自然光和日光灯照射组(p<0.05),葡萄汁中花色苷含量与抗氧化能力呈正相关,说明4℃或避光条件能显著延缓葡萄汁贮藏期间花色苷等酚类物质的降解,有利于保持其抗氧化活性。因此,葡萄汁在贮藏时应选择低温或避光条件,以保存其活性成分和抗氧化能力。     

Relationship between nitrogen content in grapes and volatiles,namely heavy sulphur compounds,in wines

Ammonium salts were added to white grape musts, before alcoholic fermentation, in order to evaluate their influence on the heavy sulphur compound and aliphatic higher alcohol composition of resulting wines. Six grape musts were used (Trajadura, Pedernã, Loureiro, Azal Branco, Avesso and Alvarinho). Ammonium supplementation of Trajadura and Pedernã grape musts, with the highest nitrogen level, did not influence the content of heavy sulphur compounds and aliphatic higher alcohols in wines; however, the addition of ammonium salts to grape musts with low initial nitrogen content, such as Loureiro, Azal Branco and Avesso, led to a higher production of 1-propanol and a lower production of isoamyl alcohols and sulphur compounds, e.g. S-methyl thioacetate, 2-mercaptoethanol, acetic acid-3-(methylthio)propyl ester, 3-mercapto-1-propanol, 4-(methylthio)-1-butanol, 3-(ethylthio)-1-propanol, 3-methylthiopropionic acid and N-3-(methylthiopropyl)acetamide. For Alvarinho grape must, a decrease in sulphur compound concentrations in wines was only observed for 3-methylthiopropionic acid, acetic acid-3-(methylthio)propyl ester and 2-mercaptoethanol.     

Distribution of lignans in knots and adjacent stemwood of Picea abies

The distribution of lignans in knots, i.e., the branch bases encased in the stemwood, and in the adjacent stemwood of Norway spruce (Picea abies) was studied. Hydrophilic extracts in samples of three annual rings from the side wood of knots, as well as samples from the surrounding stemwood, were analysed by GC and GC-MS. The knots had an exceptionally high content of lignans (up to 15% w/w), compared to the stemwood (less than 0.05% w/w). The content decreased clearly in the radial direction from the knot pith towards the outerwood, to come down to the same level as in the surrounding stemwood. In the branches, the lignan content also decreased in the radial direction from the branch pith outwards. The lignan content decreased sharply outwards in the branches and came down to the same levels as in the stemwood already 20 cm outside of the stem.     

Winery grape-residue extract: Effects on quality and sensory attributes of cooked chicken meat

Sensory analysis, instrumental color, pH, and thiobarbituric acid reactive substances (TBARS) were determined on cooked chicken meat with and without grape seed extract during refrigerated storage. The effectiveness of extracts of winery grape residue from the grape varieties ‘Isabel’ and ‘Niagara’ were tested to evaluate their effectiveness at delaying lipid oxidation in cooked chicken meat and stored under refrigeration (4±1°C). The samples were aerobically and vacuum packaged and stored for 14 days. ‘Isabel’ grape extract (IGE) and ‘Niagara’ grape extract (NGE) proved effective at promoting oxidative stability when applied at concentrations of 40 or 60 mg of gallic acid equivalents (GAE)/kg, with results similar to the synthetic antioxidant butylated hydroxytoluene (BHT). The antioxidant efficiency of the extracts was highly dependent on the concentration used. The addition of grape-residue extracts combined with vacuum packaging proved to be a good method for increasing lipid stability in cooked chicken meat stored under refrigeration.     

Antibacterial activity of plants used in cooking for aroma and taste

Thirty-three plants used in cooking for aroma and taste were examined for antibacterial activity against pathogens causing foodborne infections. Vibrio parahaemolyticus and Staphylococcus aureus were sensitive to many kinds of plant extracts, whereas Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella Enteritidis populations decreased in only six, one, and three plant extracts, respectively. The polyphenol content in the plants was significantly different between the antibacterial plants and nonantibacterial plants, indicating that the polyphenols were related to the antibacterial action of these plants. Antibacterial activity of various concentrations of leaf extracts from Japanese persimmon, white cedar, and grape were investigated. Japanese persimmon and white cedar leaf extracts at low concentrations affected L. monocytogenes and V. parahaemolyticus rapidly. With grape leaf extract at low concentrations, the population of L. monocytogenes decreased similarly to Japanese persimmon and white cedar leaves. This study demonstrates that many plants used in cooking for aroma and taste contain polyphenols and exhibit antibacterial activity against foodborne pathogens.     

Changes in polyphenol and polysaccharide content of grape seed extract and grape pomace after enzymatic treatment

Grape seed extract and grape pomace are rich sources of polyphenols. The aim of this study was to evaluate the release of polyphenols, the solubilisation of carbohydrate, and the antioxidant capacity of these grape by-products after enzymatic reaction with carbohydrases (cellulolytic and pectinolytic activities) and tannase for 24 h. The use of tannase in these by-products, and pectinase in grape pomace changed the galloylated form of catechin to its free form, releasing gallic acid and increasing the antioxidant activity. In grape pomace, cellulase treatment was not efficient for phenolic release and antioxidant activity improvement. The addition of carbohydrases to grape pomace, either alone or in combination, degraded the cell wall polysaccharides, increasing the content of monosaccharides. These results provide relevant data about the potential of pectinase, tannase and combinations of enzymes on the release of polyphenols and monosaccharides from grape by-products, improving the antioxidant capacity and the nutritional value.     

Ferric Ions Reduce the Antioxidant Activity of the Phenolic Fraction of Virgin Olive Oil

ABSTRACT: The antioxidant activity of relatively polar extracts from virgin olive oil was investigated in sunflower oil stripped of tocopherols and in tocopherol-stripped sunflower oil-in-water emulsions. The extracts were found to be effective as antioxidants in both media in the absence of added metal ions. However, the antioxidant activity was markedly reduced by the presence of added ferric chloride. In sunflower oil-in-water emulsions (pH 5.4) containing ferric chloride, all concentrations of olive oil polyphenols exhibited pro-oxidant effects. It appears that the reducing action of olive oil polyphenols accelerates oxidation of oil and especially of emulsions containing Fe (III) by reducing ferric ions to ferrous ions, which are effective pro-oxidants during storage.     

Characterization of Goethe white wines: influence of different storage conditions on the wine evolution during bottle aging

The aim of this study was to characterize Goethe white wines, produced in the region around Urussanga, Santa Catarina State, Brazil, in terms of their organic acids and polyphenols content, browning index, and in vitro antioxidant activity and to evaluate the evolution of these wines during bottle storage under two distinct conditions. The wines were analyzed utilizing spectrophotometry and liquid chromatography. In relation to the phenolic compounds investigated, trans-caftaric acid was the major component in all samples, ranging from 42.63 to 52.31 mg L^?1, followed by catechin (18.90 to 28.09 mg L^?1) and epicatechin (2.68 to 4.35 mg L^?1). Samples with higher levels of total polyphenols also had higher antioxidant activity. The antioxidant activity, total polyphenols content, and browning index increased with storage. Quercetin showed the strongest correlation (R = 0.84) with antioxidant activity before and after bottle aging. Samples kept at room temperature with light exposure presented greater degradation of phenolic compounds and lower browning index values than the samples stored under controlled conditions. Principal components analysis (PCA) separated the samples according to storage conditions and wine samples. The results clearly verified that the factors light, temperature, and bottle position affected significantly the chemical composition of white wines.