西兰花种子发芽过程中生理活性物质含量的变化

以西兰花种子为试材,测定不同品种西兰花种子中萝卜硫苷和萝卜硫素含量,分析选取的种子在发芽过程中抗坏血酸、总酚、花色苷、萝卜硫苷、黑芥子酶活性和萝卜硫素含量的变化。结果表明,10种西兰花种子中萝卜硫苷和萝卜硫素含量差异显著,两者在LX5种子中含量最高,分别为134.06μmol/g DW和11.37 mg/g DW,且硫苷水解的产物中萝卜硫素的含量最高。LX5中,抗坏血酸在发芽过程中逐渐生成,发芽4 d时高达127.49mg/100 g FW,随后逐渐下降;总酚在发芽过程中逐渐下降,发芽5 d时其含量下降42.14%;花色苷含量与抗坏血酸含量变化趋势基本一致;萝卜硫苷和萝卜硫素含量在发芽过程中呈下降趋势;黑芥子酶活性在0~3 d无显著变化,随后逐渐增强。     

不同光质对西兰花芽苗菜营养品质及抗氧化性的影响

为了研究光对芽苗菜的影响,本试验以西兰花为材料,阐述了不同光质对其营养品质和抗氧化特性的影响。结果表明:与白光对照相比,蓝光和UV-B处理后子叶中可溶性蛋白和花青苷的含量均显著(p<0.05)提高,苯丙氨酸解胺酶和查尔酮异构酶活性也相应提高;与白光相比,蓝光处理下全株鲜重、可食鲜重和可食率并无明显差异,但蓝光处理能够显著增加子叶中萝卜硫苷的含量(p<0.05)。与红光相比,蓝光处理下抗超氧阴离子活性和清除DPPH自由基能力也显著提高(p<0.05)。与UV-B相比,蓝光处理的西兰花芽苗菜生长未受到抑制,而且蓝光还可显著提高子叶中可溶性糖含量、可溶性蛋白含量、总酚的含量以及花青苷含量。综合考虑,蓝光是提高西兰花芽苗菜营养与功能品质的最佳光质。     

蓝光光周期对甘蓝芽苗菜营养品质的影响

该文以“新夏 50”和“紫红钻”两种甘蓝种子为试材,研究蓝光光周期（0、4、8、12、16、20、24 h/d）对甘蓝芽苗菜生长状况及营养品质的影响。结果表明：蓝光抑制甘蓝芽苗菜生长;“新夏50”和“紫红钻”芽苗菜中抗坏血酸含量分别在光周期16 h/d和12 h/d时最高;“紫红钻”中花色苷含量显著高于“新夏50”,在光周期20 h/d最高;蓝光显著提高芽苗菜中硫苷含量,“新夏50”和“紫红钻”分别在光周期16 h/d和12 h/d时最高,“新夏50”中脂肪族和吲哚族硫苷含量显著高于“紫红钻”;蓝光处理提高两种甘蓝芽苗菜异硫氰酸酯形成量,均在光周期8 h/d达到最高,但“紫红钻”异硫氰酸酯形成量显著高于“新夏50”。总的来说,“紫红钻”芽苗菜营养价值显著高于“新夏50”,12 h/d～16 h/d是相对比较适合的蓝光光周期。     

西兰花热风干燥特性及品质研究

目的 探究不同切分大小和不同干燥温度对西兰花粉品质的影响。方法 新鲜的西兰花经过汽蒸处理后进行切分(3 cm ×3 cm, 0.5 cm×0.5 cm)和干燥(55、60、65、70、75、80 ℃)处理, 并对西兰花粉干燥过程中含水量变化以及叶绿素、花色苷、总酚、维生素C、可溶性蛋白、萝卜硫苷含量和萝卜硫素形成量 进行研究。结果 随着干燥温度的升高, 切分程度越小的西兰花干燥速率增长越快。高温使西兰花粉中绿色损失, 80 ℃ (3 cm×3 cm)的粉末颜色较差、叶绿素损失显著多于其他粉末, 其它处理的粉末颜色均较好。西兰花粉叶绿素和萝卜硫苷含量均随干燥温度升高呈先升高后降低的趋势, 总酚含量随温度变化无显著差异 (p＞0.05)。70 ℃ (3 cm×3 cm)处理的西兰花粉花色苷、维生素C和可溶性蛋白含量最高。65 ℃(3 cm×3 cm)的西兰花粉中萝卜硫素形成量最高, 为5.37 mg/g, 与70 ℃(3 cm×3 cm)的无显著差异。结论 经80 s汽蒸预处理, 花球直径和茎梗长度切分为3 cm, 在70 ℃热风干燥 处理200 min制得的西兰花粉品质最佳。     

MgSO4处理对西兰花芽苗菜生理活性物质和抗氧化能力的影响

本实验研究了外源喷施0、25、50、75 mmol/L的MgSO4对西兰花芽苗菜生长状况、生理活性物质含量和抗 氧化能力的影响。结果表明：MgSO4处理对西兰花芽苗菜造成了生长胁迫效应;叶绿素和总酚含量随着MgSO4浓度 的增大而增加,抗坏血酸含量却随着MgSO4浓度的增加而降低。发芽5 d的西兰花芽苗菜中总硫代葡萄糖苷（简称 硫苷）和萝卜硫素含量显著高于发芽8 d的,但发芽8 d的黑芥子酶活力高于发芽5 d的;MgSO4处理后,总硫苷和萝 卜硫素含量及黑芥子酶活力显著提高,但50 mmol/L和75 mmol/L MgSO4处理组之间差异不显著。MgSO4处理显著提 高了西兰花芽苗菜的抗氧化能力,但1,1-二苯基-2-三硝基苯肼自由基清除率在50 mmol/L和75 mmol/L处理组之间无 显著差异,H2O2清除率随MgSO4浓度的增加逐渐增强。因此,综合考虑,50 mmol/L MgSO4对于提高西兰花芽苗菜 的营养价值和保健功能是较适合的浓度。     

等离子体处理对西兰花芽苗生产及活性物质含量的影响

为实现西兰花芽苗中萝卜硫素、多酚、黄酮等生物活性物质的富集,以此来降低生产成本,本研究采用等离子体处理诱导方法,研究等离子体处理条件对不同品种西兰花芽苗生长和活性物质的影响。结果显示:等离子体处理电压、时间对西兰花芽苗发芽状态及活性物质含量都有显著影响（P<0.05）,在电压30 kV,处理时间2 min条件下,西兰花芽苗发芽5 d后发芽率、芽长、芽重较对照都有显著增加,萝卜硫素含量达到3.24 mg/g DW,较未处理提高了6.75倍。不同品种西兰花芽苗中萝卜硫素、总酚、总黄酮含量及抗氧化活性存在显著差异（P<0.05）,其中马尼拉的萝卜硫素和总硫苷含量最高,而曼陀绿和绿玉的总酚和总黄酮含量最高。等离子体处理后文兴、马尼拉、绿玉和绿剑的总酚和总黄酮含量及抗氧化能力较对照处理均有所提高。综上,西兰花芽苗经等离子体处理是富集萝卜硫素的有效方式,可显著提升芽苗功效并降低萝卜硫素获取成本。     

气介式超声强化西兰花热风干燥过程中硫苷分解代谢途径相关物质的变化

为探究气介式超声对西兰花热风干燥过程中硫苷分解代谢的影响，本文研究了西兰花小花球在气介式超声联合热风干燥（20 kHz，60 ℃，125.2和180.1 W/dm2）过程中的干燥特性以及硫苷、萝卜硫素、抗坏血酸、Fe2+和酚酸含量以及黑芥子酶、体外抗氧化活性的变化规律。结果表明:相比于单独热风干燥，超声处理不仅可以加快干燥进程（125.2和180.1 W/dm2超声处理下干燥时间分别比单独热风干燥缩短11.1%和17.8%），同时，超声联合热风干燥过程中3-吲哚甲基硫苷含量增加且黑芥子酶活力增强。180.1 W/dm2气介式超声联合热风干燥终点样品中3-吲哚甲基硫苷、萝卜硫素含量和黑芥子酶活力分别比单独热风干燥终点的样品高出10.7%、26.0%和15.2%，Fe2+含量比单独热风干燥终点的样品低8.1%，表明超声处理减少了Fe2+对硫苷酶促降解的干扰，能够促进4-甲基硫氧丁基硫苷降解形成萝卜硫素，但超声处理对西兰花干燥过程中抗坏血酸含量、游离酚酸含量和体外抗氧化活性变化影响不明显。本研究表明气介式超声联合热风干燥既能加快西兰花干燥进程，又能促进4-甲基硫氧丁基硫苷的转化，并对生物活性成分具有一定的保护作用。     

光质对苜蓿芽苗菜营养品质和抗氧化特性的影响

采用发光二极管精确调制光质和光量,研究光谱能量分布对苜蓿芽苗菜营养品质和抗氧化特性的影响,以黑暗作为对照。结果表明：与对照和其他光质处理相比,蓝光能显著提高苜蓿芽苗菜中可溶性蛋白、游离氨基酸、VC、总酚类物质和总黄酮的含量以及清除1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基的能力,并显著降低硝酸盐的含量;红光能显著提高鲜质量产量;白光处理更利于提高干质量产量,显著提高类胡萝卜素和硝酸盐的含量;黄光下培养6、8、12 d的苜蓿芽苗菜槲皮素含量显著提高,苯丙氨酸解胺酶（phenylalanine ammonia-lyase,PAL）活性也相应提高,且槲皮素含量与PAL活性呈显著正相关。总体而言,蓝光有利于提高苜蓿芽苗菜的营养品质。     

光质对烤烟苗期幼苗色素含量和光合特性的影响

通过发光二极管(LED)准确获取单色光源,研究了单色光对烤烟幼苗色素含量和光合特性的影响。结果表明:红光、蓝光和绿光处理均会显著降低烤烟苗期幼苗色素含量,而红蓝复合光与对照冷白光差异不显著;红蓝复合光和深红光可提高烤烟苗期幼苗光合作用速率,降低胞间CO2浓度,光合性能优于其他单色光;单色蓝光使烤烟苗期幼苗可溶性蛋白含量显著增加,但降低可溶性糖含量,单色红光显著降低可溶性蛋白含量,但可增加可溶性糖含量,红蓝复合光处理可溶性糖含量、可溶性蛋白含量均有增加。     

不同光质处理对采后桃果皮色泽及花色苷代谢的影响

为研究不同光质处理对桃果采后色泽的影响,探讨光照对桃果花色苷代谢的调控机制,本实验以‘中桃九号’为实验材料,在（22±1）℃条件下对桃果进行不同光照处理（红、绿、蓝、白光）,光照时间12 h/d,以黑暗处理为对照。分析不同光照处理后桃果色泽、花色苷含量,及花色苷合成途径酶活力、结构基因和相关转录因子表达水平的变化。结果表明：红光、绿光对桃果皮着色没有明显影响,白光有微弱的促进作用,而蓝光能显著促进桃果皮色泽的提升,采后第6天时蓝光处理组桃果皮花色苷含量达到27.26mg/kg,分别是白光处理组和对照组的4.48倍和10.34倍。在蓝光作用下,花色苷合成途径酶活力以及结构基因和转录因子表达水平在大多数时间点显著高于对照组以及其他光照处理组（P<0.05）。其中,结构基因PAL、CHS、F3H、DFR、ANS、UFGT和转录因子MYB10.1的表达水平与桃果皮色泽参数以及花色苷含量呈显著正相关。综上,蓝光处理通过上调花色苷合成通路诱导桃果皮花色苷的合成和积累。研究结果将加深对光照调控植物花色苷代谢机制的理解,同时为研发桃采后色泽调控技术提供理论依据。     

Intensifying sulforaphane formation in broccoli sprouts by using other cruciferous sprouts additions

Sulforaphane is a significant chemopreventive compound which is the predominant glucosinolate in broccoli sprouts. However, the existence of the epithiospecifier protein could direct the hydrolysis of glucosinolates toward sulforaphane nitrile formation instead of sulforaphane. Therefore, the study aimed on improving the yielding of sulforaphane in broccoli sprouts with a new method of the united hydrolysis of cruciferous sprouts. According to the results, the addition of radish, rocket and rape sprouts to broccoli sprouts could promote the hydrolysis of the glucoraphanin to anticancer effective sulforaphane to 2.03, 2.32 and 1.95-fold, respectively, compared to single broccoli sprouts. Meanwhile, the formation of non-bioactive sulforaphane nitrile in these three groups decreased greatly. However, the addition of mustard sprouts had no positive effect. These observations could make a contribution to the potential chemoprotective effects of broccoli sprouts.     

Effects of germination conditions on ascorbic acid level and yield of soybean sprouts

The effects of light illumination on the ascorbic acid content and growth of soybean sprouts were investigated. Among the six light qualities studied, ultraviolet light had the highest promoting effect on the ascorbic acid content in soybean sprouts, increasing it by 77.0% compared with the darkness control, while red light had the highest promoting effect on the growth of soybean sprouts, increasing the total fresh weight by 16.6% compared with the darkness control. Experiments with different durations of ultraviolet and red light illumination in a day showed that 12 h ultraviolet (500 Lx) and 12 h red (1000 Lx) light diurnal cycles had the highest promoting effects on both the ascorbic acid level and fresh weight of soybean sprouts, increasing the ascorbic acid content and total fresh weight by 78.7 and 17.4% respectively compared with the darkness control. The results indicated that germination of soybeans under 12 h ultraviolet and 12 h red light diurnal cycles was an effective process for increasing the yield and enhancing the nutritional quality of soybean sprouts. Copyright © 2005 Society of Chemical Industry     

NaCl胁迫对西兰花芽苗叶黄素积累及抗氧化能力的影响

为探究NaCl胁迫对西兰花芽苗叶黄素富集及抗氧化能力的影响,本实验以“青峰”西兰花种子为实验原材料,研究了不同浓度NaCl溶液处理对西兰花芽苗的芽长、鲜重、干重、含水率、可溶性蛋白、还原糖、丙二醛、脯氨酸、叶黄素含量及抗氧化酶[超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）]活性的影响。结果表明,不同NaCl浓度对西兰花芽苗生长影响较大,随NaCl浓度由0~300 mmol/L变化,叶黄素含量先升高后下降。经100 mmol/L NaCl胁迫处理至第4 d收获的芽苗中叶黄素含量为546.25 μg/g,比对照组增加了37.54%,该条件下芽苗的芽长、鲜重、干重、含水率、可溶性蛋白、还原糖含量也均明显提高,较对照组分别增加了20.88%、161.16%、68.65%、2.86%、54.90%和40.0%,SOD、POD、CAT抗氧化酶活性与对照组相比分别增加了36.26%、14.62%、32.34%。本研究为通过NaCl胁迫西兰花种子萌发来提高叶黄素含量提供了新的方式,为开发功能性西兰花芽苗食品提供参考。     

Effect of 2, 4-epibrassinolide on main health-promoting compounds in broccoli sprouts

The combined treatment with 2, 4-epibrassinolide (EBR) (2, 20, and 200 nmol/L) and NaCl (0, 40, and 160 mmol/L) on the germination rate, fresh weight, contents of ascorbic acid and glucosinolates, activities of myrosinase and antioxidant ability of broccoli sprouts was investigated. The influence of EBR on the content of glucosinolates in broccoli sprouts varied with the concentrations of EBR and NaCl. The content of total glucosinolates and glucoraphanin in broccoli sprouts treated with 2 nmol/L EBR plus 40 mmol/L NaCl was increased by 86% and 85%, respectively, and the activity of myrosinase was significantly improved by 20 nmol/L EBR treatment with or without NaCl. In addition, the content of ascorbic acid was significantly increased after treatment with 20 nmol/L EBR, and the combined treatment with 20 nmol/L EBR plus 40 mmol/L NaCl significantly enhanced the accumulation of ascorbic acid when compared with the 40 mmol/L NaCl treatment alone. These results indicated that the combined treatment with 2 nmol/L EBR plus 40 mmol/L NaCl as well as EBR treatment solely at 20 nmol/L could be useful ways for selective increase of glucosinolates or ascorbic acid, the main health-promoting compounds in broccoli sprouts.     

Seed Viability and Functional Properties of Broccoli Sprouts during Germination and Postharvest Storage as Affected by Irradiation of Seeds

ABSTRACT:  The viability of broccoli seeds and functional properties, such as ascorbic acid, carotenoid, chlorophyll, and total phenol contents, of broccoli sprouts grown from irradiated seeds were evaluated. The seeds were irradiated using electron beam and gamma ray at doses up to 8 kGy. High germination percentages (>90%) were observed in seeds irradiated at ≤4 kGy, but the yield ratio and sprout length decreased with increased irradiation dose. Irradiation at ≥6 kGy resulted in curling of the sprout roots. Germinated seeds contained higher amounts of nutrients than raw seeds but the nutritional quality of sprouts decreased during postharvest storage. Radiation treatment hampered the growth of irradiated seeds resulting in underdeveloped sprouts with decreased ascorbic acid, carotenoid, and chlorophyll contents. In addition, the decrease in functional content of sprouts was more substantial in samples grown from high-dose (5 kGy) irradiated seeds than that of the low-dose (1 kGy) treated ones. Seed irradiation did not negatively affect the total phenol content of sprouts. In general, electron beam and gamma irradiation of broccoli seeds showed similar effects on the viability and functional properties of sprouts.     

Modifying the Processing and Handling of Frozen Broccoli for Increased Sulforaphane Formation

Frozen broccoli can provide a cheaper product, with a longer shelf life and less preparation time than fresh broccoli. We previously showed that several commercially available frozen broccoli products do not retain the ability to generate the cancer‐preventative agent sulforaphane. We hypothesized that this was because the necessary hydrolyzing enzyme myrosinase was destroyed during blanching, as part of the processing that frozen broccoli undergoes. This study was carried out to determine a way to overcome loss of hydrolyzing activity. Industrial blanching usually aims to inactivate peroxidase, although lipoxygenase plays a greater role in product degradation during frozen storage of broccoli. Blanching at 86 °C or higher inactivated peroxidase, lipoxygenase, and myrosinase. Blanching at 76 °C inactivated 92% of lipoxygenase activity, whereas there was only an 18% loss in myrosinase‐dependent sulforaphane formation. We considered that thawing frozen broccoli might disrupt membrane integrity, allowing myrosinase and glucoraphanin to come into contact. Thawing frozen broccoli for 9 h did not support sulforaphane formation unless an exogenous source of myrosinase was added. Thermal stability studies showed that broccoli root, as a source of myrosinase, was not more heat stable than broccoli floret. Daikon radish root supported some sulforaphane formation even when heated at 125 °C for 10 min, a time and temperature comparable to or greater than microwave cooking. Daikon radish (0.25%) added to frozen broccoli that was then allowed to thaw supported sulforaphane formation without any visual alteration to that of untreated broccoli.