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1.
陶雯  张瑞  杨宁  吴慕慈  何静仁 《食品科学》2022,43(12):66-65
以苹果果胶为原料,经果胶酶酶解、硝酸-亚硒酸钠法超声辅助制备硒化低分子果胶,并以果胶、硒化果胶、低分子果胶作对照,采用体积排阻色谱-示差检测器-激光光散射联用技术、离子色谱法、傅里叶变换红外光谱、紫外光谱、热重分析、粒径和电位对其结构进行表征;采用氢化物-原子荧光光谱法检测硒含量,咔唑硫酸法检测半乳糖醛酸含量;利用体外实验研究其抗氧化活性以及对α-葡萄糖苷酶的抑制作用。结果表明:硒化低分子果胶的得率为(78.07±1.66)%,硒含量达(148.29±1.97)μg/g,半乳糖醛酸含量为(68.02±3.21)%;相对分子质量集中在8.905×103,在单糖组成上,硒化低分子果胶与果胶、硒化果胶、低分子果胶相同,主要由鼠李糖、阿拉伯糖、半乳糖、葡萄糖、木糖、半乳糖醛酸组成,但含量存在一定差异,红外光谱分析表明结构中含有Se=O、C—O—Se键,实现了低分子果胶的硒化。紫外光谱在约200 nm波长处具有果胶多糖的吸收峰,经过酶解与硒化处理后,热稳定性降低,分散度变高,体系稳定性增强。果胶、硒化果胶、低分子果胶、硒化低分子果胶对羟自由基、超氧阴离子自由基的清除作用以及α-葡萄糖苷酶活力的抑制作用均较好,呈剂量效应关系,且硒化低分子果胶效果最强。  相似文献   

2.
对兰州肉苁蓉多糖进行组成分析和抗氧化活性研究。采用沙生植物兰州肉苁蓉肉质茎鲜样,使用传统水提醇沉法进行兰州肉苁蓉粗多糖(CLP)的提取,利用DEAE-纤维素阴离子交换色谱柱法对粗多糖CLP进行洗脱,得到中性糖CLP-1和酸性糖CLP-2。用高效凝胶渗透色谱法(HPGPC)和高效液相色谱法(HPLC)对其分子量和单糖组成进行测定,通过DPPH自由基清除实验和总抗氧化能力实验进行抗氧化活性测定。根据HPGPC对分子量测定得出兰州肉苁蓉多糖有多个洗脱峰,其多糖分子量主要分布在0~10 kDa之间,为不均一的小分子量杂多糖;经过分级得到的中性糖CLP-1和酸性糖CLP-2的单糖组成差异明显,CLP-1中较明显的单糖及占比分别为:甘露糖2.78%、半乳糖醛酸4.07%、葡萄糖88.62%、半乳糖1.80%、阿拉伯糖2.39%;CLP-2中为:鼠李糖5.79%、半乳糖醛酸7.78%、葡萄糖9.99%、半乳糖13.30%。根据抗氧化实验结果分析,CLP-1的抗氧化效果最好,2.0 mg/mL浓度下对DPPH自由基清除能力高达91.73%,IC50为0.383 mg/mL,且同一浓度下总抗氧化能力高于CLP和CLP-2。本文对兰州肉苁蓉多糖进行初步分析,为兰州肉苁蓉的进一步研究提供基础的数据支撑。  相似文献   

3.
通过水提醇沉法制备薇菜粗多糖(water-soluble polysaccharide of Osmunda japonica,WOJP),并用二乙氨乙基(diethylaminoethyl,DEAE)-纤维素层析法对其进行分离纯化,获得2?个多糖组分薇菜中性糖(neutral WOJP,WOJP-N)和薇菜酸性糖(acidic WOJP,WOJP-A)。WOJP-N的分子质量为31.8?kDa,由鼠李糖、半乳糖醛酸、葡萄糖、半乳糖、木糖和阿拉伯糖组成,对应各成分物质的量比为9.1∶5.7∶13.3∶37.6∶5.6∶11.8;WOJP-A的分子质量为15.7?kDa,由鼠李糖、半乳糖醛酸、半乳糖和阿拉伯糖组成,对应各成分物质的量比为7.0∶56.4∶26.1∶5.2。傅里叶变换红外光谱分析结果表明,WOJP-N主要由β-构型的半乳糖组成;WOJP-A主要由吡喃半乳糖醛酸组成,且存在部分酯化修饰。体外抗氧化活性实验结果表明,WOJP的Fe3+还原能力、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)清除能力和超氧阴离子清除能力与VC相当,具有较好的抗氧化活性,其中WOJP-N和WOJP-A在WOJP发挥抗氧化活性时具有协同作用,两者均是WOJP发挥抗氧化活性的多糖组分。本研究结果可为进一步研究薇菜多糖的构效关系和开发功能性食品提供依据,并为薇菜的应用提供理论参考。  相似文献   

4.
本研究旨在解析漆酶介导合成的百香果高酯果胶(passion fruit high-methoxy pectin,PFP)和对香豆酸(p-coumaric acid,CA)及阿魏酸(ferulic acid,FA)衍生物的分子特性、红外光谱特征、体外抗氧化活性以及免疫活性,并与百香果高酯果胶-抗坏血酸衍生物(PFP-laccase-vitamin C,PFP-L-VC)(没有酚氧化成醌类并键结的参考组)对照比较。所得百香果高酯果胶-阿魏酸衍生物(PFP-laccase-ferulic acid,PFP-L-FA)和百香果果胶-对香豆酸衍生物(PFP-laccase-p-coumaric acid,PFP-L-CA)的总酚含量显著高于PFP和PFP-L-VC(P<0.05)。相较于PFP的重均分子质量mw(190.5 kDa),PFP-L-CA的mw大幅提高至256.5 kDa,PFP-L-FA无明显变化,而PFP-L-VC则降低。两种酚酸衍生物都具有显著较小的Mark-Houwink-Sakurada指数(α)、环动半径(radius of gyration,Rg)和非均向性构型参数(ρ),显示其构象为无规则线圈状、链段柔软致密的球体。百香果高酯果胶-酚酸衍生物傅里叶变换红外光谱显示1 625 cm-1(自由羧基)处的峰面积明显减小,1 739 cm-1(酯化羧基)处的峰面积明显增加,说明酚酸与果胶的羧基形成酯基。和PFP相比,PFP-酚酸衍生物具有更高的体外抗氧化活性(羟自由基清除力、超氧阴离子自由基清除力、Fe2+螯合力和总还原力)以及免疫活性(巨噬细胞增殖率、NO生成量与中性红吞噬能力),可刺激小鼠巨噬细胞释放较多的NO并增强细胞中性红吞噬能力。PFP-L-CA在1,1-二苯基-2-三硝基苯肼自由基清除率方面更优于PFP-L-FA和PFP-L-VC,与酚酸结构有关。本研究发现酚酸可赋予PFP衍生物优良的体外抗氧化活性和免疫活性,可为酚酸改性果胶在食品胶体和膳食纤维领域中的应用提供参考。  相似文献   

5.
改性苹果果胶性质及抗氧化活性   总被引:1,自引:0,他引:1  
以苹果果胶为原料,采用酸碱修饰和高压蒸汽法2种方法分别制备酸碱改性和热改性苹果果胶,并在分析苹果果胶改性前后理化性质的基础上,进一步研究了其体外抗氧化活性。结果表明:酸碱改性和热改性后的苹果果胶与未改性果胶相比:半乳糖醛酸含量由(683.92±4.51)mg/g分别增加到(910.61±1.08)mg/g和(780.19±5.68)mg/g,酯化度由(77.26±1.20)%分别降低到(35.48±1.90)%和(33.67±1.28)%。改性后果胶分子质量降低,多酚和蛋白质含量均较低(分别小于3 mg/g和7 mg/g)。改性前后苹果果胶的1,1-二苯基-2-三硝基苯肼自由基清除率、羟自由基清除率、2,2’-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐自由基清除率和超氧阴离子自由基清除率均随果胶质量浓度的增大而增强,而且酸碱改性更有助于其抗氧化活性的提高,这可能与其半乳糖醛酸含量增加有关。  相似文献   

6.
PMP柱前衍生化HPLC法测定黄秋葵多糖的单糖组成   总被引:1,自引:0,他引:1  
采用1-苯基-3-甲基-5-吡唑啉酮为柱前衍生化试剂,结合反相高效液相色谱法,建立同时测定黄秋葵多糖中8?种单糖组分的方法。采用InfinityLab Poroahell C18色谱柱为固定相,流动相为磷酸盐缓冲液(0.1?mol/L,pH?6.85)-乙腈(82∶18,V/V),流速为1.0?mL/min,柱温25?℃,紫外检测器,波长250?nm。各单糖组分的线性范围较宽,相关系数均大于0.999,检出限为0.13~0.45?mg/kg,定量限为0.43~1.49?mg/kg,相对标准偏差小于5%,加标回收率为94.51%~106.44%。方法灵敏度高、准确性好、实用可靠,适用于黄秋葵多糖的单糖组分分析。同时测定从黄秋葵中顺序提取的热水浸提物(hot buffer soluble solution,HBSS)、螯合剂浸提物(chelating agent soluble solution,CHSS)和碱提物(dilute alkaline soluble solution,DASS)的单糖组成,确定其单糖组分的物质的量比。HBSS中,甘露糖∶鼠李糖∶葡萄糖醛酸∶半乳糖醛酸∶葡萄糖∶半乳糖∶阿拉伯糖=0.1∶7.0∶0.4∶5.8∶0.9∶14.6∶1.5;CHSS中,鼠李糖∶半乳糖醛酸∶半乳糖∶阿拉伯糖=4.7∶61.8∶9.6∶5.3;DASS中,甘露糖∶鼠李糖∶半乳糖醛酸∶葡萄糖∶半乳糖∶阿拉伯糖=9.5∶5.4∶1.3∶10.8∶2.4∶7.6。  相似文献   

7.
赵文俊  陆思名  彭东  赵超凡  杜冰  黎攀 《食品科学》2022,43(13):131-139
本研究对美藤果粕可溶性膳食纤维(sacha inchi soluble dietary fiber,SISDF)进行了抗氧化和免疫活性评价。利用离子色谱、凝胶色谱和傅里叶变换红外光谱等方法对SISDF结构进行表征。结果表明:SISDF的重均分子质量为401 479 Da,是以吡喃糖为主链的大分子多糖。单糖组成中,半乳糖醛酸相对含量最大(46.49%),其次为鼠李糖(18.95%)、木糖(17.60%)和半乳糖(11.25%)等;当SISDF的质量浓度为2 mg/mL时,1,1-二苯基-2-三硝基苯肼(2,2-diphenyl-1-picrylhydrazyl,DPPH)自由基清除率为68.57%、羟自由基清除率为69.83%、2,2’-联氮-双(3-乙基苯并噻唑啉-6-磺酸)(2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid),ABTS)阳离子自由基清除率为70.35%,表现出一定的抗氧化能力;在62.5~1 000 μg/mL质量浓度范围内,SISDF能够极显著增强RAW264.7巨噬细胞的增殖活性和吞噬活性(P<0.01),提升RAW264.7巨噬细胞的一氧化氮、白细胞介素(interleukin,IL)-1β、IL-6、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)因子分泌水平。SISDF具有良好的抗氧化活性和免疫活性,具备开发为天然食品抗氧化剂和消炎保健品的潜力。  相似文献   

8.
陆胜民  尹颖  陈剑兵  夏其乐  张俊 《食品科技》2012,(8):208-211,215
为研究低分子柑橘果胶的抗前列腺癌细胞活性,以商品化柑橘果胶为原料,121℃处理30min制得低分子柑橘果胶,测定了其分子质量、半乳糖醛酸含量、酯化度和体外抗人前列腺癌激素不依赖型PC3细胞活性。结果表明,制得的低分子柑橘果胶的平均分子质量为6685u、半乳糖醛酸含量为78%、酯化度为38%,柑橘果胶中对应的数值分别为55654u、64%、59%。低分子柑橘果胶对PC3细胞有很强的抑制作用,中剂量(2.5mg/mL)下抑制率可达38%,高剂量(5~10mg/mL)下抑制率达80%~90%,肿瘤细胞增殖(72h)的半数抑制浓度为(3.55±0.44)mg/mL,相对于天然的柑橘果胶,其抗前列腺癌细胞活性显著增强。  相似文献   

9.
利用DEAE-Cellulose离子交换色谱柱对豆渣可溶性多糖进行分离纯化,获得了2 种电荷均一的水溶性大豆多糖(soluble soybean polysaccharides,SSPS)SSPS-A1和SSPS-A2。进一步对组分SSPS-A1进行凝胶过滤色谱,获得电荷和分子质量均一的多糖组分SSPS-A1-c。对其进行分子质量、单糖组成、红外光谱和核磁分析。结果表明:SSPS-A1-c分子质量为31.6 kDa,主要由半乳糖醛酸(galacturonic acid,GalA)、半乳糖(galactose,Gal)和阿拉伯糖(arabinose,Ara)组成,其物质的量比为GalA∶Gal∶Ara=17.3∶44.9∶19.1;还含有少量的鼠李糖、葡萄糖和木糖;红外光谱分析表明SSPS-A1-c具有O—H、C—H和C=O等酸性多糖的特征吸收峰,同时SSPS-A1-c还存在一定程度的甲酯化或乙酰化修饰;核磁共振图谱表明,SSPS-A1-c具有α-1,5-Araf、α-t-Araf以及β-t-Galp的化学位移,推测其含有阿拉伯糖半乳聚糖(AG型)果胶结构域。同时还含有α-1,4-GalpA和CH3COO-的化学位移,推测其含有部分乙酰化的半乳糖醛酸聚糖(HG型)果胶结构域,结果和单糖组成和红外分析结果一致。研究结果将为豆渣可溶酸性多糖的应用提供理论依据,对豆渣的综合开发利用具有重要意义。  相似文献   

10.
黄海  杨湘  夏玮  张文清 《食品工业科技》2022,43(18):399-407
为探究茉莉花渣中果胶型多糖的结构特征与免疫调节作用,本研究通过水提醇沉、蛋白脱除、阴离子交换柱层析和凝胶柱层析分离得到两种多糖JSP-3和JSP-4。通过相对重均分子量测定、单糖组成测定、部分酸水解液-质联用测定以及核磁共振波谱分析了两种多糖结构特征,最后以小鼠巨噬细胞RAW 264.7为模型,通过探究其对小鼠巨噬细胞的增殖率、吞噬率、ROS产生量以及NO、TNF-α、IL-6分泌量的影响来研究免疫调节作用。结果表明,JSP-3和JSP-4为两种均一多糖,相对重均分子量分别为15.48 kDa和 44.75 kDa,主要由半乳糖醛酸、鼠李糖、半乳糖和阿拉伯糖构成,存在不同比例的半乳糖醛酸聚糖结构域(JSP-3:32.87%±3.53%;JSP-4:68.64%±0.67%)与鼠李糖半乳糖醛酸聚糖结构域(JSP-3:61.12%±3.37%;JSP-4:28.28%±0.46%),说明两者均为果胶型多糖。与对照组相比,JSP-3和JSP-4在12.5~100 μg/mL的浓度范围内无细胞毒性,在一定浓度下能够通过促进小鼠巨噬细胞的吞噬作用,显著增加ROS产生量以及NO、TNF-α和IL-6的分泌量(P<0.05)。在相同浓度下,JSP-4比JSP-3能够刺激细胞分泌更多的NO、TNF-α和IL-6,说明JSP-4具有更强的免疫调节作用,这可能与其更高的半乳糖醛酸结构域比例和相对重均分子量有关。上述研究成果初步证明了茉莉花渣果胶型多糖的免疫调节作用,为其在免疫调节剂方面的应用提供了初步依据。  相似文献   

11.
The relationship between antioxidant capacity and levels of various antioxidants in rice bran and brown rice powder was evaluated. Three different varieties of Venezuelan rice, namely, Cimarrón, Zeta 15 and FONAIAP-1, were studied using ferric reducing antioxidant power (FRAP), 2,2′-azinobis-3-ethylbenzotiazoline-6-sulphonic acid (ABTS), and oxygen radical absorbance capacity (ORAC) to measure antioxidant capacity. The results showed that rice varieties contained different levels and combinations of total polyphenols, γ-oryzanol, α- and γ-tocopherols and α-, γ- and δ-tocotrienols. Compared to brown rice powder, rice bran contained most of the antioxidants and had correspondingly higher values of antioxidant capacity. Principal components analysis and multiple regression on the data indicate that FRAP was sensitive to polyphenols and total tocotrienols, while ORAC was sensitive to polyphenols and total tocopherols. ABTS was the least sensitive of all assays tested. Thus, results from antioxidant capacity assays must be interpreted with caution particularly in complex systems and that further study is necessary to define more precisely the nature of the relevant chemical reactions.  相似文献   

12.
A new vitamin E, δ-tocomonoenol, has been isolated from Actinidia chinensis (kiwi) fruits. The new structure, 2,8-dimethyl-2-(4,8,12-trimethyltridec-11-enyl)chroman-6-ol, has been elucidated on the basis of EIMS, 1D, and 2D NMR spectral data. GC–MS analysis of peels and pulps of kiwi showed that the new compound, together with δ-tocopherol, is mainly present in the fruit peel, whilst α-tocopherol is present in a similar amount in both matrices. The compound was tested for its radical-scavenging and antioxidant capabilities, by measuring its ability to scavenge DPPH (2,2′-diphenyl-1-picrylhydrazyl radical) and anion superoxide radical, and inhibit the formation of methyl linoleate conjugated diene hydroperoxides and TBARS (thiobarbituric acid reactive species).  相似文献   

13.
Heat flux differential scanning calorimetry (DSC) and electron spin resonance spectroscopy (ESR) were used to assess the activity and the thermal stability of antioxidants in four vegetable oils. Sunflower oil (SO) and high oleic sunflower oil (HOSO), both rich in diunsaturated fatty acids (FA), low trans oil (LT) and partially hydrogenated palm oil (PHPO), both containing monounsaturated FA, were analyzed by isothermal heat flux DSC, with or without 300 mg/kg of antioxidant: ascorbyl palmitate (AP), α-tocopherol (αT), δ-tocopherol (δT) and propyl gallate (PG). DSC experiments showed that δT is the most effective antioxidant for SO and PG for the less unsaturated oils. SO and PHPO were also analyzed by ESR at 120 and 145 °C, respectively. ESR results confirm the strongest antioxidant activity of δT and PG for SO and PHPO, respectively. Therefore, the present study demonstrates that DSC and ESR are valuable technologies to study activity and stability of antioxidants at high temperature. Moreover, experiments performed in the presence of the spin-trap N-tert-butyl-α-phenylnitrone (PBN), suggest that δT delay lipid oxidation through a different reaction mechanism when compared to αT. A different mechanism between tocopherols isomers in delaying lipid oxidation has been hypotized.  相似文献   

14.
目的:研究乳杆菌发酵对坛紫菜发酵上清液营养成分及其抗氧化和抑制糖脂代谢关键酶活性的影响。方法:采用福林-酚法和亚硝酸钠-硝酸铝法分析乳杆菌发酵坛紫菜上清液中总酚和总黄酮含量;基于1H核磁共振代谢组学技术分析发酵上清液中的主要代谢产物;通过1,1-二苯基-2-三硝基苯肼自由基、2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)阳离子自由基、羟自由基清除能力实验和α-葡萄糖苷酶及胰脂肪酶活力分析实验,评价发酵清液的抗氧化活性和抑制α-葡萄糖苷酶及胰脂肪酶的活性。结果:乳杆菌发酵可有效提高坛紫菜发酵上清液中总酚和总黄酮的含量,促进乳酸、精氨酸、脯氨酸等代谢产物的释放。乳杆菌发酵增强坛紫菜上清液的抗氧化活性,其中乳杆菌发酵对羟自由基的清除效果最为显著,相当于700 μg/mL VC对羟自由基的清除能力。此外,乳杆菌发酵坛紫菜上清液对α-葡萄糖苷酶的抑制活性较未发酵坛紫菜上清液提高了2.1~2.2 倍,对胰脂肪酶的抑制活性最高可达(95.3±1.3)%,相比于未发酵坛紫菜上清液提高了95.7%;上清液中总酚和总黄酮的增加是其抗氧化活性和α-葡萄糖苷酶及胰脂肪酶抑制活性增强的主要原因。结论:乳杆菌发酵可提高坛紫菜发酵上清液的抗氧化活性和α-葡萄糖苷酶及胰脂肪酶抑制活性,具有减缓和辅助治疗糖尿病、肥胖等慢性疾病的潜在功效。  相似文献   

15.
Fang Wang  Jianxiong Yang 《LWT》2012,46(1):239-244
Caffeic acid (3,4-dihydroxycinnamic acid, CA) has been identified as an important source of natural antioxidants in various agricultural products. SMND-309, which is a degradation product of salvianolic acid B, is a novel conjugate of CA, but little information has been known about its antioxidant activities. In present study, we compared in vitro antioxidant activities of CA and SMND-309 using different assays such as DPPH radical scavenging assay, hydroxyl radical scavenging assay, superoxide radical scavenging assay, total antioxidant activity, reducing power, and lipid peroxidation assay. Butylated hydroxytoluene (BHT) and Vitamin C (Vc) were used as the standard antioxidants. At the concentration of 20 μg/ml, SMND-309 and CA exhibited 93.4% and 92.1% scavenging on DPPH radical, while BHT and Vc indicated an scavenging of 37.9% and 93.0% at the same concentration, respectively. Furthermore, SMND-309 is more effective on total antioxidant activity and hydroxyl radical scavenging than CA.  相似文献   

16.
The effect of α-, γ-, and δ-tocopherols (enrichment: 1000 ppm) on the peroxide formation in rapeseed oil triacylglycerols (RSOTG) was evaluated. The oxidation process was initiated by gamma-irradiation with doses of 4 and 10 kGy. Whereas a pronounced antioxidant effect was observed for γ- and δ-tocopherol (sequence: δ- > γ-tocopherol), the inhibition extent of α-tocopherol was insignificant.  相似文献   

17.
β-Casein and α-casein showed radical-scavenging activities in aqueous solution, whereas bovine serum albumin (BSA), α-lactalbumin and β-lactoglobulin showed much weaker antioxidant activity, when assessed by the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical-scavenging assay. However, β-casein and α-casein showed reduced antioxidant activity after storage at 30 °C. An increase in radical-scavenging activity and a fall in fluorescence of the protein component were evident after 6 h, when BSA, β-lactoglobulin or casein were mixed with EGCG, and excess EGCG was removed, indicating the formation of a complex with this protein on mixing. Storage of all the proteins with EGCG at 30 °C caused an increase in the antioxidant activity of the isolated protein component after separation from excess EGCG. This showed that EGCG was reacting with the proteins and that the protein-bound catechin had antioxidant properties. The reaction of EGCG with BSA, casein and β-lactoglobulin was confirmed by the loss of fluorescence of the protein on storage, and the increase in UV absorbance between 250 and 400 nm. The increase in antioxidant activity of BSA after storage with EGCG was confirmed by the ferric reducing antioxidant potential (FRAP) and the oxygen radical antioxidant capacity (ORAC) assays.  相似文献   

18.
《Food chemistry》2003,83(3):371-382
In this study, antioxidant and antimicrobial activities of water and ethanol extracts of anise (Pimpinella anisum L.) seed (PAS) were investigated. The antioxidant properties of both extracts of PAS were evaluated using different antioxidant tests, including reducing power, free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activities. Twenty μg/ml of water and ethanol extracts exhibited 99.1 and 77.5% inhibition of peroxidation in linoleic acid system, which was greater than the same concentration of α-tocopherol (36.1%). These various antioxidant activities were compared with synthetic antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and α-tocopherol. The water extract of PAS exhibited greater antioxidant capacity than that of ethanol. Antimicrobial activity tests were carried out using disc diffusion methods with 10 microbial species.  相似文献   

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