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1.
在单因素试验基础上应用正交试验方法对芒果核多酚提取条件进行优化并初步评价其体外抗氧化活性。试验确定乙醇为最佳提取溶剂;各因素对多酚物质提取量的影响依次为料液比乙醇提取浓度=提取时间提取温度;用乙醇溶液提取芒果果核中多酚物质的最佳工艺条件为乙醇浓度70%,料液比1∶25(g/m L),提取时间120 min,提取温度60℃,芒果核多酚物质提取含量可达4.36 mg/g。抗氧化活性试验结果表明芒果核多酚物质对羟基自由基、超氧阴离子自由基及DPPH自由基的清除率分别为90.9%、83.3%、90%。优化的芒果核多酚提取工艺合理、可行,芒果核多酚物质具有较强的抗氧化性。  相似文献   

2.
采用溶剂回流提取方法,对石榴皮总多酚的提取工艺进行优化并测定其抗氧化活性。通过单因素和响应面优化设计确定了石榴皮多酚最佳提取工艺条件。同时研究了提取物对DPPH自由基、羟自由基、超氧阴离子自由基的清除作用以及对脂质过氧化物的抑制作用。结果表明,乙醇体积分数70%、提取温度89℃、料液比1︰26(g/mL)的条件下提取2.5 h,总多酚含量214.58 mg/g。提取物对DPPH自由基的半清除浓度EC50为0.014 mg/mL;对羟自由基的半清除浓度DC50为0.034 mg/mL;对超氧阴离子的半清除质量浓度HC50为3.82 mg/mL;对体外脂质过氧化的半抑制质量浓度IC50为0.019 mg/mL。  相似文献   

3.
为探究火麻籽粕多酚的提取工艺及评价其抗氧化活性,在单因素试验基础上,通过响应面试验优化火麻籽粕中多酚的微波辅助提取工艺,并从DPPH自由基清除能力、羟基自由基清除能力、超氧阴离子自由基清除能力和铁离子还原能力4个方面来评价其抗氧化活性。结果表明,最佳提取工艺条件为乙醇体积分数58% 、微波功率311 W、微波时间3.2 min、微波温度50℃、液料比50∶1(mL/g),在此条件下火麻籽粕多酚实际提取量为5.86 mg/g,与理论提取量相对误差仅为0.34% 。试验所选浓度范围内,相较于VC,火麻籽粕多酚对DPPH自由基、羟基自由基、超氧阴离子自由基的清除能力更强,同时还具有较强的还原能力。  相似文献   

4.
确定了黑果腺肋花楸多酚的最佳提取工艺,并测定其抗氧化活性。以超声波辅助提取,对乙醇浓度、液料比、提取温度、提取时间进行单因素实验,在此基础上以提取量为指标,利用响应面法优化工艺条件;通过对DPPH、ABTS及超氧阴离子自由基清除率的测定,评价其多酚类物质的抗氧化活性。结果表明:黑果腺肋花楸多酚最佳提取条件为液料比44∶1(m L∶g)、乙醇浓度55%、提取温度45℃、提取时间90 min,在此条件下黑果腺肋花楸多酚提取量达19.549 mg/g。黑果腺肋花楸多酚对DPPH、ABTS及超氧阴离子自由基有较强清除作用,并与其质量浓度呈正相关关系,说明其多酚具有良好的抗氧化活性。  相似文献   

5.
张锦华  徐蔓  白宝清  董晨 《食品工业科技》2018,39(16):183-190,212
利用响应面法优化无花果干果中多酚和黄酮物质的提取工艺,并分析其体外抗氧化活性。在单因素实验基础上,根据Box-Behnken试验设计对提取条件(乙醇体积分数、超声温度、超声时间、料液比)进行分析与优化,从而考察其对多酚及黄酮提取量的影响并进一步研究无花果干果提取物的抗氧化活性。结果显示,最佳工艺参数为:乙醇体积分数60%,超声温度51 ℃,超声时间52 min,料液比1:45 (g/mL)。在此工艺条件下,多酚的提取量为(2.72±0.37) mg/g,总黄酮的提取量为(20.89±0.57) mg/g。与VC进行抗氧化活性比较发现,在多酚质量浓度(2.50 mg/g)相同条件下,无花果干果中多酚提取物的还原能力、清除羟自由基率(最高为95.54%)以及清除DPPH自由基率(最高为66.73%)均高于VC,清除超氧阴离子自由基率(最高为35.15%)低于VC。在黄酮质量浓度(10.60 mg/g)相同条件下,无花果干总果黄酮提取物各抗氧化指标均低于VC。另外,人工模拟胃肠液处理对无花果干果提取物抗氧化活性的影响实验发现,经人工胃液处理后,提取液的还原能力和羟自由基清除能力明显著升高,而DPPH自由基和超氧阴离子自由基清除能力明显降低,经人工肠液处理后,相应的还原能力和超氧阴离子自由基清除能力明显升高,而DPPH和羟自由基清除能力明显下降。  相似文献   

6.
采用响应面法优化超声波提取蒲公英茶中多酚工艺,建立多酚得率与料液比、乙醇体积分数、提取温度、超声时间4因素的数学模型,确定蒲公英茶多酚的最适提取工艺参数;以抗脂质过氧化能力和清除自由基能力评价蒲公英茶多酚的抗氧化活性。结果表明:蒲公英茶多酚提取的最佳工艺条件为料液比1:20、乙醇体积分数20%、提取温度60℃、超声时间110 min,多酚得率为32.43 mg/g。在此优化条件下,蒲公英茶多酚具有较强的抗脂质过氧化能力,对DPPH自由基、羟自由基及超氧阴离子自由基均具有较强清除作用,半数抑制浓度分别为1.908、0.444、0.393 mg/m L。  相似文献   

7.
以青金桔皮为原料,选取乙醇作为提取溶剂,采用Folin-Ciocalteu法测定其多酚含量,探讨了乙醇浓度、提取温度、料液比和提取时间对多酚得率的影响。在单因素实验的基础之上,通过正交实验优化提取工艺。采用DPPH自由基法、ABTS自由基法和铁氰化钾还原力法测定青金桔皮中多酚提取物的抗氧化活性。结果表明,青金桔皮多酚的提取工艺为乙醇浓度60%(v/v),温度55℃,料液比1∶30(g/m L),提取时间3h,提取1次,在此条件下多酚的得率为3.68%(以干重计,w/w)。抗氧化性实验表明,青金桔皮多酚提取物具有较强的清除DPPH自由基和ABTS自由基能力,其IC50值分别为1.38mg/m L和0.49mg/m L,还原力测定实验也得出相似的结果。  相似文献   

8.
采用响应面法优化菟丝子中总黄酮的提取工艺。在单因素实验的基础上,以乙醇浓度、提取温度、料液比、提取时间为自变量,总黄酮得率为因变量,运用Box-Behnken设计-响应面优化菟丝子中总黄酮回流提取工艺。并通过菟丝子总黄酮对DPPH自由基、羟自由基和超氧阴离子自由基的清除作用来评价其抗氧化活性。结果表明:菟丝子总黄酮最佳提取工艺条件为乙醇浓度90.0%、提取温度70℃、料液比1:15 g/mL、提取时间100 min。在此条件下,菟丝子总黄酮得率为(34.65±0.02) mg/g,与模型预测值(34.37 mg/g)相对误差为0.81%,说明回流提取菟丝子总黄酮的工艺稳定可靠。菟丝子总黄酮对DPPH自由基、羟自由基和超氧阴离子的IC50分别为0.067、7.209、0.119 mg/mL,抗坏血酸对DPPH自由基、羟自由基和超氧阴离子的IC50分别为0.082、1.731、0.054 mg/mL,体外抗氧化试验结果表明,菟丝子总黄酮对DPPH自由基具有较强的清除能力,明显高于抗坏血酸;而对羟自由基、超氧阴离子具有一定的清除能力,但清除能力低于同浓度的抗坏血酸。  相似文献   

9.
采用正交试验对银叶树果壳中单宁的提取工艺进行优化,并研究银叶树果壳单宁对羟基自由基、超氧阴离子自由基和对DPPH自由基的清除作用。结果表明最佳提取工艺条件为丙酮浓度70%、料液比1∶100(g/mL)、温度40℃、时间30 min,单宁得率为7.32%。银叶树果壳单宁对羟基自由基、超氧阴离子自由基和DPPH自由基均有明显的清除作用,且清除率随单宁浓度的增加而增大。  相似文献   

10.
以狗尾草为原料,研究狗尾草中多酚的提取工艺和体外抗氧化活性。在单因素试验的基础上,采用响应面法优化狗尾草多酚的超声波辅助提取工艺,以抗氧化剂二丁基羟基甲苯(BHT)264为阳性对照,对其羟基自由基、DPPH自由基、超氧阴离子自由基清除能力进行研究。结果表明,在超声功率250 W的条件下,最佳提取工艺为料液比1∶20(g∶mL)、乙醇体积分数70%、提取温度80 ℃、提取时间75 min,此条件下多酚提取率平均值为3.23%,与理论值3.45%相近,最佳工艺具有可行性,提取得到的狗尾草多酚对羟基、超氧阴离子、DPPH自由基的半抑制浓度(IC50)分别为1.217、0.476、0.227,当样品浓度达到试验最大浓度时,清除率分别为(48.56±3.46)%、(88.05±2.95)%、(65.34±4.19)%,表现出较好的体外抗氧化活性。  相似文献   

11.
This research was performed in order to compare the water and acetone extracts of raw and boiled for 10, 20, 40 and 60 min Korean lotus roots (KLR) and Polish white onion (PWO) in the contents of their bioactive compounds, antioxidant activity and thermostability.It was found that polyphenols (mg GAE/g), flavanols (μg GAE/g), flavonoids (mg CE/g), anthocyanins (mg CGE/kg) and tannins (mg CE/g) in water extract of raw lotus roots were 14.18 ± 0.7, 8.41 ± 0.5, 1.09 ± 0.06, 21.3 ± 1.2 and 7.29 ± 0.4, and of white onion - 11.11 ± 0.6, 6.78 ± 0.3, 0.71 ± 0.03, 17.00 ± 0.9 and 1.64 ± 0.08, respectively, and significantly higher in KLR (P < 0.05). The antioxidant activity of raw KLR water extract (139.4 ± 6.1, 53.1 ± 3.6 and 89.3 ± 4.6 μmol TE/g for DPPH, CUPRAC and ABTS, respectively) was significantly higher than in white onion (23.84 ± 1.8, 31.9 ± 2.1 and 38.14 ± 2.6 for DPPH, CUPRAC and ABTS, respectively, P < 0.05).The thermostability of the water KLR extract’s of polyphenols, flavanols, flavonoids, anthocyanins and tannins was high and even after 60 min of boiling remains as 40.0, 42.3, 50.5, 41.4 and 41.0%, respectively. After 60 min of boiling the most thermostable compounds were flavonoids - remaining at 50.5% in water extract of KLR. Also after 60 min of boiling the thermostability of the antioxidant activity of water extracts of KLR remained significantly high: 40.6, 42.3, 46.3 and 43.6%, according to DPPH, FRAP, ABTS and CUPRAC assays, respectively.Similar relationship was obtained with acetone extracts, but the value was lower than with the water ones. In conclusion, the contents of some bioactive compounds, the antioxidant activity and the thermostability in water and acetone extracts of KLR are significantly higher than the same indices in PWO. FTIR and fluorimetry can be used as additional markers for the characterization of bioactive compounds in vegetables.  相似文献   

12.
Ziziphus mauritiana (masau) fruits are consumed by many people in Zimbabwe. The fruits contribute significantly to people’s diet when they are in season. The objective of this study was to determine the nutritional content of the fruits and, hence, quantify their contribution to the diet. Samples of masau were collected in two seasons (August 2006 and August 2007). Both macronutrients and micronutrients were determined using standard AOAC methods of analysis. Dry matter content ranged from 21.1 ± 0.2 to 24.1 ± 0.3 g 100 g−1 of edible portion of the sweet and sour fruits, and 84.8 ± 0.2 to 87.2 ± 0.2 g 100 g−1 for the dried fruit. Crude protein per 100 g edible portion of dry weight ranged between 7.9 ± 0.0 and 8.7 ± 0.0 g, crude fat from 0.8 ± 0.0 to 1.5 ± 0.0 g, crude fibre from 4.9 ± 0.0 to 7.3 ± 0.0 g, ash between 3.0 ± 0.0 and 4.3 ± 0.0 g and carbohydrate between 79.5 ± 0.0 and 83.2 ± 0.0 g. The fruits were rich in vitamin C (15.0 ± 0.0–43.8 ± 0.02 mg 100 g−1) and the energy values ranged between 1516.0 ± 1.73 and 1575.0 ± 2.3 kJ 100 g−1. Furthermore, the fruits contained (mg 100 g−1 of dry weight) potassium from 1865.0 ± 1.3 to 2441.0 ± 1.1, calcium from 160.0 ± 0.3 to 254.0 ± 0.1, sodium between 185.0 ± 0.1 and 223.0 ± 0.2, magnesium between 83.0 ± 0.0 and 150.0 ± 0.13 and phosphorous from 87.0 ± 0.1 to 148.0 ± 0.5. Manganese and copper contents ranged between 0.7 ± 0.03 and 1.6 ± 0.03, while iron and zinc ranged between 2.1 ± 0.43 and 4.3 ± 0.1, and 0.6 ± 0.0–0.9 ± 0.0 mg 100 g−1 of dry weight, respectively. The masau fruit is therefore a good potential source of carbohydrates, proteins and micronutrients, such as calcium, potassium, sodium, phosphorous, copper, iron, Vitamin C and zinc.  相似文献   

13.
The study compared the growth capability of probiotic (Lactobacillus acidophilus La05, Lactobacillus casei Lc01 and Bifidobacterium animalis Bb12) and non-probiotic (Lactobacillus delbrueckii subsp bulgaricus and Streptococcus thermophilus) cultures on twenty-one culture media grouped according to selectivity: non-selective agars, selective agars without antibiotics and MRS agars containing different combinations of lithium chloride, cystein, bile salts and antibiotics. Four of these media were selected for quantitative enumeration of L. acidophilus La05, L. casei Lc01, and B. animalis Bb12. The best culture media and incubation conditions for enumeration of the probiotic cultures were: B. animalis: MRS agar with dicloxacillin, 37 °C or 42 °C, anaerobiosis; L. acidophilus: MRS agar with bile salts, 37 °C or 42 °C, aerobiosis; L. casei: MRS agar with lithium chloride and sodium propionate, 37 °C or 42 °C, aerobiosis or anaerobiosis. Plating on MRS with glucose replaced by maltose, 37 °C or 42 °C, anaerobiosis, will distinguish probiotic from non-probiotic cultures. For enumeration of each probiotic in a mixed culture, the following media and incubation conditions were recommended: B. animalis: 4ABC-MRS, 42 °C, anaerobiosis, L. acidophilus: LC medium, 42 °C, aerobiosis or anaerobiosis and L. casei: LP-MRS, 42 °C, aerobiosis or anaerobiosis. In all experiments, differences in counts using pour plating or surface plating were not significant (P ≤ 0.05).  相似文献   

14.
The quality assessment of wild European eel (Anguilla anguilla) stored in ice and in boxes without ice (3 ± 1 °C) was investigated by the sensory analysis, levels of nucleotide breakdown products and biogenic amines for up to 19 days. Sensory analysis was assessed using the Tasmanian Food Research Unit Scheme. K and related values (Ki, G, P, H and Fr) were used as freshness indicators. Linear regressions (r2) obtained from K, Ki, G, P, H and Fr were 0.95, 0.96, 0.83, 0.96, 0.99 and 0.96, respectively, for eel stored in ice whereas, for eel kept in boxes without ice, the values were 0.86, 0.86, 0.96, 0.91, 0.98 and 0.86, respectively. When eel stored in ice and in boxes without ice were considered at the limit of acceptability by assessors at ∼12–14 days and ∼5–7 days, respectively, the average K, Ki and P values were ∼70–85%, H values were ∼60% and Fr values were ∼10% for both storage conditions. The level of histamine exceeded the legal limit (5 mg/100 g fish) in eel stored without ice after 6–7 days and, in ice, after 13–14 days of storage, at which time eels were rejected by the sensory panel. The concentrations of biogenic amines were higher in eel stored in boxes without ice than in eel kept in ice. The levels of histamine in the muscle of eel kept in boxes without ice and in ice increased to the maximum levels of 17.9 mg/100 g on day 12 and 12.6 mg/100 g on day 19, respectively.  相似文献   

15.
Studies on the effect of temperature on the development of the yam moth, Dasyses rugosella Stainton were carried out in the laboratory at four different temperatures, 20°C, 24°C, 29°C and 33°C. The mean fecundity per female at 20°C, 24°C, 29°C and 33°C was 37.6±1.9, 84.2±2.7, 112.3±3.9 and 109.3±3.9 eggs, respectively. Oviposition period ranged from 4.7 days at 20°C to 2.9 days at 33°C. Hatchability of eggs was highest at 29°C with 70.0% and lowest at 20°C with 15.0%. The developmental time decreased with increase in temperature. The mean developmental time at 20°C, 24°C, 29°C and 33°C was 13.8±0.3, 7.8±0.2, 5.1±0.2 and 3.9±0.2 days for the egg, 90.0±0.7, 50.1±0.7, 36.1±0.8 and 23.6±0.8 days for the larval stages, 22.3±2.6, 12.2±0.2, 10.1±0.1, and 7.8±0.2 days for the pupa and 126.1±0.8, 70.1±0.8, 51.3±0.9, and 35.1±0.8 days for the period from egg hatching to adult emergence, respectively. Since fecundity, oviposition and development of the moth were impaired at 20°C, storage of yam tubers at low temperatures (well below 20°C but not lower than 12°C to avoid chilling injury) will significantly retard the development of D. rugosella and help in its control. Unmated individuals lived longer than their mated counterparts. Adult females were always larger than the males. The wing span of the female ranges from 16.9-18.5 and in males from 13.0-15.0 mm. The body length for males ranged from 5.0-6.5 and was 6.5-9.0 mm for females.  相似文献   

16.
Lipoxidation in almond-derived products was investigated using the chemiluminescence (CL) and thiobarbituric acid-reactive substances (TBARS) methods to detect the first and later reaction products, respectively. The effects of light during storage at 5 °C, 22 °C and 40 °C were studied, as well as the effects of combined heat/water activity treatments in the 60–120 °C and 0.38–0.72 range. During storage, light was found to enhance the CL and TBARS values, and specific responses were observed in almond paste and the final Calisson product. During the heating of almond paste, as the initial water activity (aw) increased, the CL rate constants increased during heating to 60 °C and 80 °C, but interestingly, these values decreased during further heating to 120 °C, whereas the maximum TBARS rate constants occurred at aw 0.57 at all the heating temperatures tested. The activation energies, based on the CL and TBARS values, decreased specifically when the aw increased from 0.38 to 0.72, giving overall values ranging from110 kJ mol−1 to 60 kJ mol−1. Likewise, in the same water activity range, the temperature-dependent rate constant enhancing factor (Q10) decreased from 3.3 to 1.6.  相似文献   

17.
The antioxidant and protective properties of a synthetic soybean isoflavone (SI) were investigated using chick skeletal (leg) muscle cells (SMC) isolated from 20-day-old Linnan yellow broiler chick embryo. Skeletal muscle cells were cultured in Dulbecco’s modified Eagle’s medium treated with 0, 12.5, 25, 50, 75 and 100 μM SI, respectively, under 80 μM H2O2/FeSO4 conditions. After 24 h of incubation, SI reduced the loss of SMC under oxidative stress by H2O2/FeSO4. The addition of SI significantly promoted SMC proliferation (P < 0.01). Upon treatment with 25, 50, 75 and 100 μM SI, the activity of total superoxide dismutase in the supernatant of the media was enhanced by 17.0%, 13.0%, 13.3% and 11.9%, respectively (P < 0.05). Compared to the control, the activity of glutathione peroxidase was significantly increased only at 25 μM concentration of SI (P < 0.05), and the increment was 90.7%. The activity of catalase was increased by 49.2% and 49.1%, respectively, at 75 and 100 μM SI (P < 0.01). The concentration of creatine kinase in the media was decreased by 61.6% and 60.6%, respectively, at 75 and 100 μM SI (P < 0.01). The addition of SI did not affect the activity of lactate dehydrogenase in the media. In conclusion, the SI protected skeletal muscle cells from oxidative damage, attributed to its antioxidant activity.  相似文献   

18.
The physicochemical, thermal, pasting and gel textural properties of corn starches from different corn varieties (African Tall, Ageti, Early Composite, Girja, Navjot, Parbhat, Partap, Pb Sathi and Vijay) were studied. Amylose content and swelling power of corn starches ranged from 16.9% to 21.3% and 13.7 to 20.7 g/g, respectively. The enthalpy of gelatinization (ΔHgel) and percentage of retrogradation (%R) for various corn starches ranged from 11.2 to 12.7 J/g and 37.6% to 56.5%, respectively. The range for peak viscosity among different varieties was between 804 and 1252 cP. The hardness of starch gels ranged from 21.5 to 32.3 g. African Tall and Early Composite showed higher swelling power, peak, trough, breakdown, final and setback viscosity, and lower ΔHgel and range of gelatinization. Pearson correlations among various properties of starches were observed. Gelatinization onset temperature (To) was negatively correlated to peak-, breakdown-, final- and setback viscosity (r = −0.809, −0.774, −0.721 and −0.686, respectively, p < 0.01) and positively correlated to pasting temperature (r = 0.657, p < 0.01). ΔHgel was observed to be positively correlated with To, peak gelatinization temperature and (Tp) and gelatinization conclusion temperature Tc (r = 0.900, 0.902 and 0.828, respectively, p < 0.01) whereas, it was negatively correlated to peak- and breakdown- (r = −0.743 and −0.733, respectively, p < 0.01), final- and setback viscosity (r = −0.623 and −0.611, respectively, p < 0.05). Amylose was positively correlated to hardness (r = 0.511, p < 0.05) and gumminess (r = 0.792, p < 0.01) of starch gels.  相似文献   

19.
Three hundred and six Limousin young bulls (7 ± 1 months of age, initial body weight 273 ± 43 kg) were used to evaluate the effect of crude glycerine supplementation on animal performance, carcass characteristics and meat quality. Animals were assigned to three different diets: Control (0% of crude glycerine), G2 and G4 (2 and 4% of crude glycerine, respectively). The diets were administrated ad libitum for 240 days (final body weight 644 ± 24 kg). Average daily weight gain, average daily feed intake, the gain:feed ratio, ultrasound measures in vivo, carcass characteristics, pH, water holding capacity, drip losses, and cooking losses were not affected (P > 0.05) by diets. Diet decreased C16:0 (P < 0.01) and C16:1 (P < 0.05) contents in meat. The G4 meat showed lower C12:0, C14:0, C17:0, C18:0, C18:1, C18:2, C18:3, c9,t11-c18:2, C20:0 and C20:4 levels (P < 0.05) than control. Glycerine increased desirable fatty acid percentages (P < 0.05) in intramuscular fat.  相似文献   

20.
A total of 68 species of starchy foods, tropical fruits, leaves and tubers (101 samples), were collected on the foothills of the Colombian Andes and in the rain forests of the Colombian Pacific coast. Their edible portion was analyzed for mineral content (Ca, P, Mg, K, Na, Cl, S, Mn, Zn, Fe, Cu, Se, Co, Ni). The foods were generally high in K (36–1.782 mg K/100 g edible portion) and low in sodium (<45 mg Na/100 g edible portion). The tree foliages had the highest contents in most of the elements, especially in calcium (280–1242 mg Ca/100 g edible portion, i.e., up to 62 g Ca/kg dry matter) and iron (0.7–8.4 mg Fe/100 g edible portion). Correlations (P < 0.001) were observed between total ash and many elements, especially Ca and Mg (r =  0.77 and 0.73, respectively). High correlations were also obtained between Ca and Mg (r = 0.93).  相似文献   

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