山楂叶和果中类SOD的提取与研究

实验对山楂叶、果中类SOD(Superoxide disutase like简称SOD-L)进行了提取与研究。通过连苯三酚自氧化法对山楂叶、果中SOD-L活性进行分析,测得山楂叶提取物中SOD-L的活力为630.14 u/mg;山楂果提取物中SOD-L的活力为252.05 u/mg;在280 nm有特征性吸收峰;在Mg2+和Cu2+的存在时SOD-L的活性有着不同程度的增强。SOD-L的最适温度在40℃;最适pH值在8.0。     

微生物酵素主要功效酶活力的测定

酶的活力是微生物酵素的主要质量指标.采用紫外分光光度法测定微生物酵素中蛋白酶活力,膏状酵素为10975.5 U/g,粉状酵素为2141.25 U/g.采用NaOH滴定法测定脂肪酶活力,膏状酵素为5.41 U/g,粉状酵素为14.6 U/g.采用邻苯三酚自氧化法测定超氧化物歧化酶活力,膏状酵素为1691.112 U/g,粉状酵素为2.8 U/g.     

大豆萌发期脂肪氧化酶与脲酶活性变化及钝化方法效果评价

为探究大豆萌发期抗营养因子含量变化规律及钝化方式,以黑龙江地区的黑科56、黑农71为原料,测定此两种萌发大豆在不同萌发时间阶段中脂肪氧化酶和脲酶两种抗营养因子的活性变化,并在萌发20 h酶活性至最低时,分别以烘烤、微波、沸水漂烫3种方法处理萌发豆,比较对脂肪氧化酶与脲酶的钝化效果,筛选出适宜的钝化方式并确定其工艺参数。结果表明,萌发20 h黑科56与黑农71脂肪氧化酶活性分别为100.8 U和99 U,脲酶活性分别为4.73 U/g和4.82 U/g;钝化方式效果最佳为沸水漂烫,其工艺参数为:沸水漂烫40 s,两个品种与未漂烫的大豆相比,脂肪氧化酶活性均降低至10.9 U;脲酶活性分别降低至0.18 U/g(黑科56)和0.13 U/g(黑农71)。通过顶空固相微萃取-气相色谱-质谱联用法对钝化后的两种萌发大豆主要豆腥味物质进行了定性、定量分析,且得出脂肪氧化酶活性与豆腥味物质含量呈极显著正相关。     

羊血中Cu,Zn-SOD酶活的研究

以羊血为原料提取了Cu,Zn-SOD,利用邻苯三酚自氧化法对Cu,Zn-SOD的酶活进行了测定。实验结果表明:1L羊血中提取的Cu,Zn-SOD,经丙酮沉淀、冷冻干燥及SephadexG-100葡聚糖凝胶过滤后的酶活分别为3.2×103U/mg、4.51×103U/mg和5.85×103U/mg。     

高通量MBTH法测定β-葡聚糖酶的活力

本文建立了一种以3-甲基-2-苯并噻唑酮腙(MBTH)为氧化剂,以微孔板测定β-葡聚糖酶活力的新方法,该法特别适合于成分复杂的材料中痕量β-葡聚糖酶活力的测定。根据MBTH法测定β-葡聚糖酶解产物还原端基的特点,设计并优化了酶活力测定的关键参数。结果表明,在最适p H 5.0和30℃条件下测定β-葡聚糖酶活力,所得酶的工作浓度范围为0~12.3 m U/m L,饲料中酶的工作浓度范围均为0~2.94 U/g,本法测β-葡聚糖酶和四种饲料样品中酶的平均回收率分别为93.1%、97.5%、104.3%、97.0%、106.4%,β-葡聚糖酶活力检测限为0.37 m U/m L,定量限为1.24 m U/m L,四种饲料酶活力检测限分别为0.10 U/g、0.09 U/g、0.14 U/g、0.09 U/g,定量限分别为0.33 U/g、0.30 U/g、0.46 U/g、0.31 U/g。该法准确、低成本、省时、省力,特别是其灵敏度远高于DNS法,可极大程度上避开饲料中其它成分对测定的干扰。     

莲子心水提液体外抗氧化活性的研究

本实验研究了莲子心水提液对氧自由基的清除作用及其对脂质过氧化反应（LPO）的抑制作用。结果表明：莲子心水提液对Fenton体系产生的羟自由基和邻苯三酚自氧化产生的超氧阴离子均有清除作用,半数清除量（IC50）分别为0．218g／ml和0．245g／m1;对小鼠肝、肾匀浆自发性过氧化反应有较好的抑制作用,IC50分别为3．038mg／ml和3．577mg/ml;通过紫外分光光度法测定了莲子心中抗坏血酸含量为1．132mg／g。用NBT法测定了水提取液中SOD总活性为2062．7U/g。     

He-Ne激光和NTG复合诱变米曲霉提高其蛋白酶和淀粉酶酶活力

以分离自豆酱中的米曲霉(Aspergillus oryzae)HDF-C14为出发菌株,采用He-Ne激光和亚硝基胍复合诱变的方法获得高产蛋白酶和淀粉酶的突变株HDF-C14-HN5,并将其应用到豆酱发酵中,测定酱曲发酵时蛋白酶和淀粉酶的酶活力。所得成曲中干基蛋白酶酶活力最高可达1572.64U/g,淀粉酶酶活力最高可达2815.23U/g。此生产性发酵实验可以为该菌株投入工业化生产提供技术支撑。     

复合发酵棉籽粕营养价值及活性产物分析研究

旨在研究复合固态发酵(两株酵母和一株霉菌)对棉籽粕脱毒效果及营养价值的影响,同时分析测定发酵底物中的活性产物。结果表明:复合发酵可极显著降低棉籽粕底物游离棉酚含量(P0.01),降解率达71.90%;棉籽粕底物粗蛋白、总氨基酸和必需氨基酸含量分别提高28.96%、8.83%、7.58%;发酵54~60 h时底物中蛋白酶活力最高(酸性蛋白酶活力为931.58 U/g,中性蛋白酶活力为1 097.79 U/g,碱性蛋白酶活力为798.62 U/g),纤维素酶活力最高(滤纸酶活力为1 601.66 U/g,Cx酶活力为3 590.02 U/g,C1酶活力为1 685.35 U/g),淀粉酶活力最高为578.05 U/g;同时发酵过程产生了一定量的有机酸。     

蒲公英花中总酚酸和总黄酮含量测定及其抗氧化性能研究

测定蒲公英花75%乙醇提取液中总酚酸和总黄酮含量,并测定该提取液对超氧阴离子自由基、羟自由基和油脂自氧化的清除作用。结果表明：蒲公英花中总酚酸平均含量为4.09%,总黄酮平均含量为3.65%。提取液对超氧阴离子自由基、羟自由基和油脂自氧化均有较好的清除效果,并在供试质量浓度范围内呈现量效关系。对超氧阴离子自由基的半数抑制率IC50为96.1μg/mL,对羟自由基的IC50为7.7μg/mL。蒲公英花提取液可使花生油的过氧化值(POV)显著降低,其效果与在花生油中添加0.10%的VC相当。     

不同材料固定化柚苷酶的比较

选取壳聚糖、海藻酸钠、活性炭和氧化石墨烯对柚苷酶进行固定化,比较不同材料对柚苷酶的载酶率和固定化酶活,得到较佳的固定化材料为氧化石墨烯,其载酶率达85.61%,酶活达410.50 U/g,重复使用7次后仍能保持72.38%的相对酶活。同时研究了不同条件对氧化石墨烯固定化柚苷酶催化活性影响,得到较佳的固定条件:载酶量为每克氧化石墨烯材料承载60 mg柚苷酶,固定化温度为20℃,p H值为4.0,固定化吸附时间为9 h,优化后氧化石墨烯固定化柚苷酶的酶活为433.70 U/g,重复使用7次后仍保留78.62%的酶活。     

压榨对酿酒葡萄皮渣酚类物质提取及抗氧化活性的影响

酿酒葡萄皮渣（皮和籽）生物活性物质含量丰富,具有很高的再加工利用价值。对鲜葡萄皮渣进行压榨处理后再干燥,研究压榨对皮渣的酚类物质提取及抗氧化活性的影响。结果表明：压榨处理可以快速降低葡萄皮渣水分含量,缩短干燥时间、提高可溶性膳食纤维提取率。压榨葡萄皮总酚、原花青素的提取量均有所增加,其含量分别为19.56 mg/g和22.64 mg/g。压榨葡萄皮的抗氧化能力高于未压榨葡萄皮,其DPPH、ABTS及羟自由基清除率分别为62.90%、70.18%和41.09%,铁氰化钾还原能力及金属离子螯合能力分别为0.23%和21.33%。压榨籽和皮籽混合物的酚类物质和抗氧化活性则明显降低。抗氧化活性与总酚、原花青素存在显著的相关关系（P＜0.01）。     

Nutritional constituents and antioxidant properties of indigenous kembayau (Dacryodes rostrata (Blume) H. J. Lam) fruits

The nutritional and antioxidant properties of peels, pulp and seeds of kembayau (Dacryodes rostrata) fruits were evaluated. Kembayau seeds and pulp were rich in fat, while peels had the highest ash contents. Potassium was the most prevalent mineral in peels (380.72-1112.00 mg/100 g). In kembayau fruits, total flavonoid content (1012.74-28,022.28 mg rutin equivalent/100 g) was higher than total phenolic and total monomeric anthocyanin contents. Kembayau seeds exhibited high flavonoid and phenolic contents compared to the contents in peels and pulp. Antioxidant capacities were also higher in seeds as typified by trolox equivalent antioxidant capacity assay (51.39-74.59 mmol TE/100 g), ferric reducing antioxidant power assay (530.05-556.98 mmol Fe²⁺/100 g) and by 1,1-diphenyl-2-picryl hydrazyl radical scavenging activity (92.18-92.19%) when compared to peels and pulp. Pulp and peels of kembayau fruit may be an important source of energy and minerals for human consumption, while seeds have a good potential as antioxidants.     

红树莓籽低聚原花青素微胶囊制备工艺优化及其稳定性分析

建立制备红树莓籽低聚原花青素微胶囊的方法,旨在提高低聚原花青素的稳定性。以红树莓籽低聚原花青素为芯材,明胶和阿拉伯胶为壁材,通过单因素及响应面试验优化复凝聚法制备红树莓籽低聚原花青素微胶囊工艺,并对微胶囊化前后低聚原花青素稳定性进行比较。结果表明,低聚原花青素微胶囊最佳工艺为:壁材浓度0.75%、壁材质量比(明胶:阿拉伯胶)1:1、芯壁质量比1.05:1、固化温度10 ℃、转谷氨酰胺酶添加量22.39 g/100 g明胶,此条件下包埋率80.34%,水分含量5.64%,休止角36.4°,溶解度89.64%,粒径476 nm。受V_C、亚硫酸氢钠、温度、pH及光照影响,包埋后的低聚原花青素稳定程度明显高于包埋前。因此,微胶囊化提高了低聚原花青素稳定性,拓宽了红树莓果籽低聚原花青素微胶囊使用范围。     

黑曲霉固态发酵橘皮生产纤维素酶及淀粉酶

以橘皮为原料,以黑曲霉AS3.3928为生产菌株,采用固态发酵法生产纤维素酶和淀粉酶。通过单因素试验考察固态发酵培养基中橘皮含量、培养基含水量、接种量及发酵时间4个因素对纤维素酶和淀粉酶活力的影响。在单因素试验基础上,通过正交试验最终确定最优产酶条件为：固态发酵培养基中添加16g橘皮,并加入5mL无菌水使培养基初始含水量为64mL/100g,黑曲霉接种量15%,发酵60h。在此发酵条件下所产纤维素酶活力可达1816U/g,淀粉酶活力达196U/g。结果表明,利用黑曲霉固态发酵橘皮,非常有利于纤维素酶和淀粉酶的生产。     

红枣不同部位中有效成分含量的比较研究

为了研究红枣不同组分的营养成分分布情况,以山东大枣(骏枣)、和田玉枣(骏枣)和若羌灰枣(灰枣)为试验样品,采用比色法、高效液相色谱(HPLC)法等,对枣果不同部位(枣肉、枣皮和枣核)中的多糖、总黄酮、总酚、三萜和环磷酸腺苷(cAMP)含量进行分析测定。结果表明枣皮中的总酚和总黄酮含量分别为0.77~1.20%和0.29~0.43%,显著高于枣肉和枣核(p0.01);三萜类物质主要分布在枣皮和枣肉中,约0.36~0.40 mg/g,枣核中含量最少;多糖在枣肉中含量最高(4.72~6.13%),枣核中含量最低(0.67~1.30%);cAMP在枣皮及枣肉中含量最高,在不同品种间分布差异显著,其中和田玉枣的皮和肉中cAMP含量(0.27 mg/g、0.34 mg/g)显著高于其他两个品种(p0.05);常规非可食用部位(枣皮和枣核)占枣果总质量的20~30%。因此红枣的非可食部分的营养成分含量较高,有较好的开发前景和深加工利用价值。     

Profile of non-volatiles in whisky with regard to superoxide dismutase activity

SOD (Superoxide dismutase)-like activities of 23 kinds of single malt whisky (Scotch and Japanese) were evaluated. There was a positive correlation between SOD-like activity and the maturation age of whisky that exceeded the difference resulting from the manufacturing region. The SOD-like activity of Yamazaki 18, a typical single malt whisky in Japan, was approximately 1333 U/ml and that of non-volatile components in the whisky was 388U/mg, indicating that single malt whisky generally has a very strong SOD-like activity. To elucidate their contribution to SOD-like activity, the non-volatile components of whisky (Yamazaki 18) were ultrafiltered and separated with a Diaion HP20/water-EtOH system. Elution of the fraction less than 5000 molecular weight (<5000 MW fraction) with 60% (v/v) EtOH contributed most to SOD-like activity of the whisky. As this elution contained a considerable amount of polyphenolics, the content and SOD-like specific activity of ellagic acid, gallic acid, and lyoniresinol--the main whisky polyphenolics--were evaluated. The contribution of these compounds to the SOD-like activity of whisky was approximately 15%. Polyphenolics in whisky were relatively distributed to a higher MW fraction compared to carbohydrates in whisky, and specific activity (SOD-like activity per weight) of the >10,000 MW fraction was greater than that of the <5000 MW fraction, although the content of this fraction was low. These results indicate that various polyphenolics with higher molecular weights also contribute to the SOD-like activity of whisky together with main whisky polyphenolics.     

Antioxidant gallocatechins,dimeric and trimeric proanthocyanidins from sea buckthorn (<Emphasis Type="Italic">Hippophaë rhamnoides</Emphasis>) pomace

Residues such as peels and seeds that result from fruit juice production may contain substantial amounts of valuable natural antioxidants. In order to isolate the potential antioxidants gallocatechins and proanthocyanidins, pomace from sea buckthorn (Hippophaë rhamnoides) berries was extracted by acetone-water (75:25, v/v) and fractionated by Sephadex LH-20 gel chromatography and semipreparative HPLC. The structures of the monomeric flavan-3-ols isolated, (+)-gallocatechin and (–)-epigallocatechin, were elucidated by electrospray mass spectrometry (ESI-MS) and ¹H and ¹³C NMR spectroscopy. Five dimeric proanthocyanidins were identified by HPLC-ESI-MS(-MS) and by acid-catalyzed cleavage in the presence of phloroglucinol. Moreover, nine trimeric proanthocyanidins were tentatively identified by HPLC-ESI-MS(-MS) in the Sephadex fractions of sea buckthorn pomace. The isolated flavan-3-ols and proanthocyanidins were potent in scavenging Fremys salt, a synthetic free radical. They possessed antioxidant capacities that were higher or comparable to that of ascorbic acid or Trolox. On comparing the antioxidant capacities of monomeric flavan-3-ols and dimeric proanthocyanidins, no significant influence from the degree of polymerization (DP) was observed.     

Valuable components of raw and ripe peels from two Indian mango varieties

Mango is one of the most important tropical fruits and India ranks first in its world production. During the processing of mango, mainly for mango pulp and preparation of amchur powder, peel is a by-product. Peel forms about 20% of the whole fruit and at present it is a waste product and its disposal has become a great problem. With a view to exploit mango peel as a source of valuable components, in the present study, proximate composition, polyphenols, carotenoids, dietary fibre contents and activities of few enzymes in raw and ripe peels of two Indian mango varieties, namely, Raspuri and Badami were determined. The polyphenol contents in these peels ranged from 55 to 110 mg/g dry peel. Dietary fibre content ranged from 45% to 78% of peel and was found at a higher level in ripe peels. Similarly, carotenoid content was higher in ripe fruit peels. Vitamins C and E contents ranged from 188 to 392 and 205 to 509 μg/g dry peel, respectively; and these were found at a higher level in ripe peels. Both raw and ripe mango peels exhibited significant amount of protease, peroxidase, polyphenol oxidase, xylanase and amylase activities.     

Antioxidant Activities of Polyphenolic Compounds Isolated from Antidesma thwaitesianum Müll. Arg. Seeds and Marcs

ABSTRACT: Antidesma thwaitesianum Müll. Arg. or mao is widely used as commercial products of juice and wine in Thailand. As a result, waste products from the mao plant, such as mao seeds (MS) and mao marcs (MM), are plentiful. We aimed to purify and analyze polyphenolic content in both MS and MM and to investigate the radical scavenging activities of these polyphenolics against 1,1‐diphenyl‐2‐picryl‐hydrazyl (DPPH) and 2,2′‐Azinobis (3‐ethylbenzothiazoline 6‐sulphonate) (ABTS) radicals and thiobarbituric acid reactive products (TBARP). The results showed MS and MM to be an abundant source of polyphenols (97.32 to 130 mg gallic acid equivalents [GAE]/g) and proanthocyanidins. The radical scavenging activities of MS/MM against DPPH and ABTS radicals (IC₅₀ of 0.85 to 1.21 μg/mL) were significantly higher (P < 0.05) than that of standard trolox (IC₅₀ of 5.05 μg/mL). Activity of MS/MM extracts were 3.74 and 3.80 μg/mL trolox eq/g f.w. for the DPPH and ABTS assays, respectively. The oxidation of erythrocyte membranes using 2‐thiobarbituric acid demonstrated that the protective effect of MS/MM on lipid peroxidation is as strong as grape seed proanthocyanidin extract. These findings suggest that polyphenolic compounds and proanthocyanidins isolated from these mao extracts had much higher antioxidant activities than those of standard trolox and exhibited similar antioxidant potential to grape seed proanthocyanidin extract. These findings may also increase value of mao waste products and allow development of commercial health products.     

食用槟榔废弃籽的活性成分提取及抗氧化、α-葡萄糖苷酶抑制活性分析

针对食用槟榔加工后槟榔籽被当作废弃物而基本无大规模利用的问题,本研究以食用槟榔加工后的废弃籽为研究对象,75%的乙醇溶液为提取溶剂,超声辅助提取,得到加工后槟榔籽75%乙醇提取物（processed seed extraction,PSE）,测定其总多酚、总黄酮和原花青素含量。采用DPPH法、ABTS+法和Fe3+还原法3种测定方法对槟榔提取物体外抗氧化活性进行评价。本文还研究了PSE对α-葡萄糖苷酶活力的抑制能力。结果表明,PSE含有丰富的多酚和黄酮等活性物质,其中,总多酚含量为（127.29±5.16）mg 没食子酸/g提取物、总黄酮含量为（421.84±13.82） mg 芦丁/g提取物,原花青素含量为（87.83±6.60） mg儿茶素/g提取物。PSE检测到44种黄酮类化合物,其中儿茶素相对含量高达77.27%。PSE具有一定的自由基清除力,清除DPPH自由基和ABTS+自由基的IC₅₀值分别为（310.10±0.62）和（150.10±11.57） μg/mL。另外,PSE表现出较强的α-葡萄糖苷酶抑制能力,其对α-葡萄糖苷酶活力的抑制能力（IC₅₀值为（90.10±1.89） μg/mL）显著（P<0.05）强于阳性对照阿卡波糖（IC₅₀值为（453.60±4.02） μg/mL）。因此,回收再利用食用槟榔加工后的槟榔籽非常有必要。