Kinetics of Antioxidant-Producing Maillard Reaction in the Mixture of Ribose and Sea Cucumber (Stichopus japonicus) Gut Hydrolysates

Maillard reaction products (MRPs) were produced in sea cucumber gut hydrolysates (SCGHs)-ribose system at 75°C, 85°C, and 95°C with a pH value of 7.0 or 8.0 for 12 hour. The parameters of amount of intermediate products, fluorescence intensity, browning development, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging ability showed a positive correlation with each other in SCGHs-ribose system. The amount of intermediate products, fluorescence intensity, and browning development followed the zero-order kinetic with activation energy from 62 to 91 kJ/mol in the Maillard reaction of SCGHs-ribose system. Moreover, 2-methyl-butanal has positive and significant correlation with DPPH radical scavenging ability of SCGHs-ribose MRPs. These results suggest that Maillard reaction improves the antioxidant activity of SCGHs, which contributes to the generation of intermediate, fluorescent, browning, and volatile products of SCGHs-ribose system.     

大孔树脂纯化白背天葵多酚及其体外抗氧化研究

为了分离纯化白背天葵多酚,并探讨其体外抗氧化活性,本研究比较了8种大孔树脂对白背天葵多酚的静态吸附和解吸能力,优选出D101为最适宜纯化白背天葵多酚的树脂,并对其分离纯化的工艺进行了优化.采用DPPH和ABTS法评价其抗氧化活性.结果表明,D101树脂最佳纯化工艺为上样液浓度1 mg/mL、pH 3.1、上样液流速2 ...     

不同产地黑木耳提取物的活性

以不同产地的黑木耳(Auricularia auricula-judae )为试验对象,采用碱提法制备提取物,探讨提取物的体外抗氧化效果,对α-葡萄糖苷酶抑制作用以及对N2野生型秀丽隐杆线虫(Caenorhabditis elegans)耐甲基紫精性能的影响。结果表明,不同产地黑木耳样品提取物中糖含量不同,其中陕西镇安县黑木耳 SXA提取物中糖含量高达53.02%,浙江丽水市黑木耳 ZJA提取物中糖含量仅为26.14%;对α-葡萄糖苷酶的抑制率,以产于大兴安岭的DDA提取物最高,达38.56%,其次为分别产于黑龙江伊春和陕西镇安县的 DXA和 SXA的提取物;DPPH·清除率能力及还原力以 DXA的提取物(浓度为4 mg/mL)最强,其它黑木耳提取物效果相近;供试黑木耳DDA、DXA和SXA的提取物显著增强线虫耐甲基紫精能力。     

Chemical composition,antimicrobial, modulator and antioxidant activity of essential oil of Dysphania ambrosioides (L.) Mosyakin & Clemants

The oil presented the α-Terpinene as the major compound with 54.09% presence. Antibacterial activity demonstrated significant MIC against Staphylococcus aureus (256 μg/mL) and moderate against Pseudomonas aeruginosa (512 μg/mL). The modulating effect of antibiotics was significant against P. aeruginosa potentiating the effect of all the antibiotics tested. The IC₅₀ observed for CT LM 23 was clinically relevant (19.3 μg/mL), similar to that obtained for CA INCQS 40006 (25.2 μg/mL). The combined effect with fluconazole also showed significant results, 0.1 and 22.7 μg/mL, for CT LM 23 and CA INCQS 40006, respectively. For CA LM 77 the IC₅₀ was 101.9 μg/mL and for CT INCQS 40042 a value of 53.3 μg/mL. Regarding the modulation, both were considered of clinical relevance, 3.3 and 6.4 μg/mL. OEDA has low antioxidant activity (>1024 μg/mL). Therefore, the popular use against infections was corroborated by this work.     

<Emphasis Type="BoldItalic">In Vitro</Emphasis> Antioxidant and Anti-rhizopus Activities of Lamiaceae Herbal Extracts

Eighty-eight extracts of different polarity obtained from 18 Lamiaceae medicinal and aromatic plants were screened for their antioxidant and antifungal properties. A TLC analysis combined with two bioassays were used to detect these activities. In most cases the highest radical scavenger capacity was detected in methanolic and aqueous extracts and polyphenols may be responsible. The most interesting antioxidant activity was observed in polar extracts obtained from Lycopus europaeus, Melissa officinalis, Origanum vulgare subsp. virens and Lavandula latifolia. On the contrary, the best results for the antifungal test against Rhizopus stolonifer were produced by non-polar herbal extracts. Phlomis lychnitis, Salvia pratensis and Calamintha sylvatica caused the highest inhibition on Rhizopus growth.     

小叶榕气生根总酚酸和总黄酮含量测定及其抗氧化活性比较

以小叶榕(Ficus microcarpa L.)气生根为研究对象,在测定其不同部位的总酚酸及总黄酮含量的基础上,选用DPPH和ABTS 2种体外抗氧化评价方法比较不同部位的抗氧化活性。结果表明:首部的总酚酸和总黄酮含量高于其他部位,其总酚酸含量分别为首部0.34 mg·L-1,中部0.31 mg·L-1,尾部0.21 mg·L-1;总黄酮含量分别为首部3.88 mg·L-1,中部3.42 mg·L-1,尾部2.91 mg·L-1。抗氧化活性首部最强,中部次之,尾部较弱。总酚酸的含量和抗氧化活性之间具有很高的相关性,表明抗氧化活性可能与酚酸类物质有关。     

银杏花粉抗氧化成分的提取工艺优化

为了开发银杏花粉深加工产品,以银杏花粉为试材,以其提取液的DPPH清除率为指标,研究加热回流法、超声波法、微波法、超声-微波法提取银杏花粉抗氧化成分的效果,并通过单因素和响应面法对微波法提取工艺进行优化。结果表明,4种提取方法中,微波法提取银杏花粉抗氧化成分的效果最好。微波提取的最佳工艺为:乙醇浓度59.38%、料液比1∶30、微波功率109.85 W、微波时间13 min。本研究为银杏花粉抗氧化成分的开发利用奠定了基础。     

桑椹醋自回淋发酵生产工艺及其DPPH清除能力研究

为了确定桑椹醋自回淋发酵工艺,并探讨桑椹醋对二苯代苦味酰基自由基(DPPH)的清除能力,以秦巴山区桑椹为原料,采用液态自回流发酵法生产桑椹醋,从原料菌群、酒精发酵主产物和醋酸发酵主产物的动态变化趋势等方面对其工艺进行了分析,并采用比色法对桑椹醋总黄酮含量及其对DPPH自由基的清除率进行了测定。结果表明,桑椹果实表面携带有大量的酵母菌而几乎不带其他杂菌,酒精发酵醪除含有大量的酵母菌之外未发现有其他杂菌,酒精度在发酵48 h时达到高峰;桑椹醋生产前的醋酸菌床培育需要9~10 d,投入生产后醋酸发酵周期仅需要24 h;桑椹醋总黄酮含量高达6.68 mg/mL,对DPPH的清除作用远大于山西陈醋、镇江香醋和山楂果醋,具有良好的抗氧化作用;利用桑椹醋自身色素颜色变化可判断酸度测定时酸碱滴定终点。桑椹醋自回淋发酵工艺安全可靠、科学实用,生产效率高。     

响应面分析法优化肉苁蓉苯乙醇苷提取反应 及其抗氧化反应研究

为优选管花肉苁蓉苯乙醇苷提取最佳工艺并对经分离纯化的苯乙醇苷进行抗氧化活性评价研究,以管花肉苁蓉中的苯乙醇苷得率为检测指标,采用响应面分析法,分别优化乙醇浸提法、超声提取法、微波提取法3种方法的提取效果,选出最优条件,并进行比较;采用DPPH法体外测定苯乙醇苷的抗氧化能力。结果表明,微波辅助提取法在最短时间内具有最高的苯乙醇苷得率,超声波辅助提取法次之,而乙醇浸提法时间最长,得率最低;随着苯乙醇苷浓度的增加其DPPH自由基清除能力也不断增强,当浓度在60~70μg·mg-1时达到最大。该试验对提高管花肉苁蓉的利用率具有实际指导意义,为管花肉苁蓉中苯乙醇苷化合物的药理和生物活性研究提供参考。     

Polyphenolic compounds and antioxidant properties in mango fruits

Fruit of eight mango genotypes were evaluated for antioxidant potential by several biochemical assays (DPPH, ABTS, ORAC, FRAP, SASR and MCC) and tested for their polyphenol composition and vitamin C contents. The significance analysis demonstrated that the antioxidant capacity of Tainong 1 fruits were significantly higher than that of other genotypes, which was about 2.1–6.3-fold higher than Guifei assayed in ABTS, DPPH, ORAC and FRAP methods. The total polyphenols and flavonoids contents showed a great variety amongst mango genotypes and highly correlation with the total antioxidant capacity. It is concluded that significant genotypic difference exists in the total antioxidant capacity of mango fruits. Both total polyphenols and flavonoids are major contributors to the total antioxidant capacity in mango fruit.