RETARDATION OF MODIFICATION AND ENZYME FORMATION IN BARLEY ENDOSPERM BY STEEP LIQUORS AND OTHER SUBSTANCES

Steep liquors from barley soaked for 6 hr. or longer retard the synthesis of amylase stimulated by gibberellic acid in barley endosperm. The liquors from grain steeped for only 1 hr. are less effective. Phenolic acids such as ferulic, p-hydroxybenzoic and vanillic acids at concentrations of 100 p.p.m. also delay the induced synthesis of enzymes by gibberellic acid. Certain other compounds, including benzoxazolone, coumarin and radicinin at various concentrations likewise exert a retarding action on amylase synthesis. Steep liquors and phenolic acids at 100 p.p.m. do not interfere significantly with the onset of germination in intact barley whether treated with gibberellic acid or not. Emergence of the rootlets commences in the normal manner but after 2–3 days germination, rootlet growth is less than in untreated samples, and modification, as judged from hot water extract and soluble nitrogen, is slower. Benzoxazolone, coumarin and radicinin at low concentrations also retard rootlet growth in barley.     

萌动青稞的研究进展

萌动谷物的研究越来越受到广大学者的关注,特别是萌动青稞。萌动青稞是一种新型的功能性食品,因其具有良好的口感和较高的营养价值而受到人们的喜爱。通过比较青稞萌动前后营养成分的变化、萌动后青稞的生理功效,以及国内外萌动青稞产品的研发现状,综述了国内外萌动青稞研究进展,为我国萌动青稞的开发与利用提供参考。     

STUDIES ON DEBRANCHING ENZYMES. PART I THE LIMIT DEXTRINASE ACTIVITY OF EXTRACTS OF CERTAIN HIGHER PLANTS AND COMMERCIAL MALTS

Using pullulan as the substrate, the limit dextrinase activity of protein extracts from higher plants and from commercial malts has been measured. Extracts of ungerminated barley, rye, maize and wheat show low levels of activity which increase markedly on germination. By contrast, extracts of ungerminated oats have a high level of activity which does not increase during germination. Gibberellic acid has a significant effect on the rate of development of limit dextrinase activity in barley. Commercial samples of malt show varying amounts of limit dextrinase activity which does not correlate with the diastatic power. For comparative purposes, the α-amylase and maltotriase activities of all the protein extracts have also been measured.     

原子发射光谱法测定大麦发芽时金属离子的代谢

大麦在发芽过程中大麦内部的金属离子大麦有结合态与游离态2种存在状态。利用原子发射光谱法跟踪监测其金属离子总含量和游离态含量的变化，结果显示：在大麦发芽过程中总的离子含量一般呈现出单调的变化，而游离态的离子含量随发芽时间的不同呈现出波动变化。金属离子不同的存在状态有着不同的生理功能，通过跟踪监测离子的2种状态的含量变化，可以为研究金属离子在大麦发芽过程中的生理作用提供新的方法。     

发芽对青稞的营养成分和抗氧化活性的影响

本实验通过对青稞进行发芽处理,来研究发芽前后青稞基础营养成分、总酚、总黄酮以及抗氧化活性的变化,并以此来评价发芽对青稞的营养价值和抗氧化活性的影响。研究结果表明,发芽使青稞的蛋白质和灰分含量提高了23.4%和31.5%,使直链淀粉和脂肪含量降低了13.8%和19.2%。发芽后青稞的总酚和总黄酮含量显著提高,分别增加了85.0%和101.7%。抗氧化活性分析表明,发芽青稞的IC₅₀^DPPH值和FRAP(铁离子还原能力,ferric-reducing antioxidant power)值分别为(39.98±1.14)mg/mL和0.33~1.13 μmol V_C/g,其抗氧化能力显著高于未发芽青稞。相关性分析表明,发芽青稞较强的抗氧化能力与高的总酚和总黄酮含量显著相关(R²=0.803~0.990)。这说明发芽能够改善青稞的营养价值和功能特性,其结果为青稞的加工应用以及相关功能食品的开发提供了可靠的科学依据。     

低剂量X射线系统动力学机理分析及对大麦发芽的影响

建立了X射线强度与大麦种子发芽关系的系统动力学模型,阐释并确证了X射线对发芽大麦的影响和变化机理。研究发现,X射线对大麦种子发芽阶段的芽长、根长、生物量产生抑制作用,接受剂量为1059.65μSv/s,试验组Ⅰ在3 d后淀粉、蛋白质和脂肪含量分别比对照组延迟增加了19.8%,31.6%,33.3%,可溶性膳食纤维降低了41.8%,且变化程度与X射线强度呈正相关,但X射线对发芽率没有显著影响。     

PROMOTING GERMINATION OF FRESHLY HARVESTED BARLEY GRAIN WITH ALKALINE SOLUTIONS

Effects of immersing freshly harvested barley (Hordeum vulgare L.) grains in concentrated KOH and NaOH solutions on germination were studied in barley cv. Harrington. Promotion of germination up to 100% was achieved by alkaline treatments with a wide range of solution concentrations and immersion time. The effectiveness of alkaline treatments was dependent on maturity, presence of the hulls and moisture content of the grains. While alkaline treatments were generally not damaging to the grain, excessive exposure to the chemicals can harm the grains and adversely affect germination and subsequent growth of seedlings. Alkaline hydrolysis of the cuticles in the covering layers of the grain is at least partially responsible for the promotive effects on germination.     

THE DETERMINATION AND UTILIZATION OF GIBBERELLIC ACID IN GERMINATING BARLEY

A barley endosperm bioassay, utilizing the induction of acid phosphatase in barley endosperm seed halves, has been developed and applied to study both the development of endogenous gibberellin in grain germinating under malting conditions and the utilization of externally applied gibberellic acid. The assay is affected by barley age and variety and these observations may have practical implications. After 24 h germination the level of endogenous gibberellin-like material present in the grain was approximately 1·4 ng/corn. The biological activity of the total gibberellin-like material extracted from grain treated with gibberellic acid fell during germination although significant quantities of applied gibberellic acid had entered the grain during the first 24 h germination.     

大麦在盐胁迫下发芽时淀粉酶和蛋白酶分泌和作用的特点

利用不同浓度的NaCl溶液培养大麦,并用去离子水培养作为对照,监测大麦在发芽过程中的淀粉酶和蛋白酶。结果发现,在盐胁迫下大麦能正常地分泌淀粉酶和蛋白酶,但是淀粉酶和蛋白酶的活力降低直至被完全抑制。利用和培养液相同盐浓度的提取酶液和底物监测淀粉酶和蛋白酶的活力,检测结果表明,在盐胁迫下大麦能正常分泌淀粉酶和蛋白酶,但是活性被盐溶液抑制。     

青稞籽粒富硒发芽条件优化及其抗氧化能力分析

采用响应面法研究发芽时间、培养液pH和亚硒酸钠浓度对青稞籽粒中有机硒含量的影响,得到最佳富硒发芽工艺条件。在此条件下,进一步对青稞籽粒发芽过程中抗氧化物质含量及抗氧化能力进行分析。结果表明:青稞籽粒最佳富硒发芽工艺为发芽时间48.00 h、pH6.00、亚硒酸钠浓度10.00 mg/L,在此条件下,青稞籽粒有机硒含量为1.572 mg/kg DW,为原料的17.46倍。富硒发芽可显著提高青稞籽粒中总酚、总黄酮醇、有机硒含量以及ABTS⁺自由基清除能力(p<0.05),尽管降低了β-葡聚糖含量及铁离子还原能力(FRAP),但与未富硒组相比,富硒可有效延缓β-葡聚糖降解。相关性分析表明,总酚含量与有机硒含量、ABTS⁺自由基清除能力,β-葡聚糖含量与铁离子还原能力(FRAP)以及有机硒含量与ABTS⁺自由基清除能力均呈极显著正相关(p<0.01),其他指标间呈负相关或不相关。本研究表明,富硒处理可增加发芽青稞籽粒抗氧化物质含量,有效延缓β-葡聚糖降解,增强其抗氧化能力。     

The influence of germination conditions on beta-glucan, dietary fibre and phytate during the germination of oats and barley

This study aimed to quantify the changes caused by varying germination conditions on the contents of some bioactive compounds in barley and oats. Samples of the two grains were germinated at temperatures between 10 and 20 °C for a period of 2–6 days, using a two-dimensional central composite design. The germination temperature had only minor effect in comparison with the germination time. Slight changes in the mineral content of the malts were observed, mainly caused by steeping. Phytate has been seen as an anti-nutritional compound, as it complexes minerals and lowers their bioavailability. The phytate content in barley malts was considerably lower than in the native kernels. Variations in the germination conditions did not have a significant effect on phytate content. In oats, degradation of phytate was significantly enhanced by prolonging the germination period. It was possible to retain the amounts of soluble dietary fibre, when short germination periods were applied. However, long germination periods caused an extensive breakdown of soluble dietary fibre, especially beta-glucan. The content of insoluble fibre, however, was increased by applying long germination periods for oat malts.     

脉冲电场对啤酒大麦萌发性质的影响

在啤酒麦芽制备过程中引入脉冲电场(PEF)技术,对浸渍后的大麦种子进行不同电场强度的处理,以了解PEF对大麦萌发性质的影响。结果表明,PEF处理有利于提高大麦萌发活力和相关理化性质。大麦籽粒经电场强度1.5、3.0、4.5、6.0、7.5 kV/cm处理后,萌发大麦的芽长、根长、根数、鲜重、干重、发芽势、发芽率、简化活力指数、还原糖含量、β-葡聚糖酶活力、α-淀粉酶活力、β-淀粉酶活力、可溶性蛋白质和氨基态氮含量等指标与对照组比较均有明显提高,发芽势、根长、β-葡聚糖酶活力、α-淀粉酶活力和β-淀粉酶活力提高的幅度分别为38.96%、43.33%、21.46%、26.48%和23.57%。对14项指标进行主成分分析的结果表明,当电场强度为6.0 kV/cm时,脉冲电场对大麦萌发的促进效果最好。     

萌发对青稞甜醅饮料的活性成分及其抗氧化活性的影响

目的 探究青稞籽粒萌发对所制青稞甜醅饮料的活性成分及其抗氧化活性的影响。方法 对青稞籽粒进行不同时间的萌发预处理, 再进行甜醅发酵并与纯净水、稳定剂复配制备青稞甜醅饮料, 以未萌发青稞籽粒制备的饮料为对照, 测定饮料的总酚、总黄酮含量及对2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐[2-azinlbis-(3-ethylbenzthiazoline-6-sulphonate), ABTS]、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl, DPPH)和羟自由基的清除率。结果 不同时间萌发时间处理条件下, 青稞甜醅饮料的活性成分含量及其抗氧化活性相较于对照均有所提升, 其中总酚和总黄酮含量均在萌发第40 h时达到最高, 分别为2.69 mg/mL和1.71 mg/mL, 分别比对照 2.21和1.35 mg/mL提高了21.72%和26.67%。经萌发处理后的青稞甜醅饮料对ABTS自由基和羟自由基清除能力在萌发第48 h时清除率分别达到64.64%和76.97%, 分别比对照48.83%和67.61%提高了32.38%和13.84%, 对DPPH自由基清除能力在萌发第40 h时清除率达到最高为94.11%, 比对照86.28%提高了9.07%。结论 青稞籽粒经萌发处理后制得的青稞甜醅饮料具有良好的抗氧化能力, 为提高青稞系列产品的附加值提供参考。     

国产大麦蛋白质含量及酶活力变化对麦芽品质的影响

选用蛋白质含量不同的6种国产大麦,五种蛋白组分含量,蛋白酶活力变化及对其制成麦芽理化指标进行了研究。国产大麦蛋白含量较高,各蛋白组分因品种不同差异较大,参与大麦代谢活动的组分波动较大,贮存蛋白变化相对平稳,研究表明大麦蛋白酶活力与五种蛋白组分含量不具有相关性,而制成麦芽后,麦芽蛋白酶活力与麦芽泡沫蛋白成负相关r=-0.733(p<0.05),与麦芽盐溶蛋白成负相关r=-0.789(p<0.05),与麦芽库值成正相关r=0.694(p<0.05)。     

Use of Chemiluminescence HPLC for Measurement of Positional Isomers of Hydroperoxy Fatty Acids in Malting and the Protein Rest Stage of Mashing

Fatty acid hydroperoxides (9- and 13-hydroperoxides of linoleic acid and linolenic acid) were extracted from barley, malt and wort, and quantified by chemiluminescence HPLC. Although not detected in dried barley (<0·5 μmol kg⁻¹ (dry wt)), the concentrations of hydroperoxides increased during germination (up to 156 μmol kg⁻¹ (dry wt) in the case of 9-hydroperoxylinoleic acid). Lipoxygenase (LOX) activity increased more than two-fold during germination. LOX activity and hydroperoxide concentrations were reduced considerably on kilning of malt. During mashing on a laboratory scale, malts with higher total LOX activities produced higher concentrations of hydroperoxides. The concentrations of 9-hydroperoxides were double those of the 13-hydroperoxides during malting and up to 10-fold greater during mashing, indicating a greater activity of LOX-1 in both processes.     

盐胁迫对大麦发芽时植酸酶活性和无机磷代谢的影响

利用不同浓度NaCI盐溶液培养大麦，发现在不同浓度盐胁迫下大麦发芽时植酸酶活性有很大差别，但是并没有被抑制，培养过程中仍然作用植酸盐释放出无机磷。检测大麦发芽过程中的无机磷，发现随着盐浓度的升高，无机磷在大麦中的积累增大，而且在盐浓度为2％培养大麦时，无机磷的含量基本是持续增加的。盐浓度越高，大麦根芽和叶芽生长越缓慢，在盐浓度2％时大麦根芽和叶芽基本不生长，即基本不消耗无机磷来合成新的细胞。     

Evaluation of hot water and electron beam irradiation for reducing Fusarium infection in malting barley

The use of Fusarium-infected barley for malting may lead to mycotoxin production and decreased product quality. Physical methods for the treatment of Fusarium-infected barley may prevent these safety and quality defects and allow the use of otherwise good quality barley. Hot water and electron beam irradiation were evaluated for their effectiveness in reducing Fusarium infection while maintaining germinative energy in barley samples. Hot-water treatments involved temperatures of 45, 50. 55, and 60 degrees C and treatment times of 0, 1, 5, 10, and 15 min. Electron beam irradiation involved doses ranging from 0 to 11.4 kGy. Treatment with water at 45 degrees C for 15 min resulted in a reduction in Fusarium infection from 32 to 1% after 15 min, with only a very slight reduction in germination. Treatment with water at 50 degrees C for 1 min resulted in a reduction in Fusarium infection from 32 to 2%, and no effect on germination was observed for up to 5 min of treatment. At higher water temperatures. Fusarium infection was essentially eliminated, but germination was also severely reduced. Electron beam irradiation of Fusarium-infected barley reduced Fusarium infection at doses of >4 kGy, and a slight increase in germination for dry samples was observed with doses of 6 to 8 kGy. Doses of >10 kGy significantly decreased germination. Physical methods may have potential for the treatment of Fusarium-infected malting barley.     

超声波促进大麦发芽及对麦芽品质的影响

主要探讨了超声波对大麦萌发及对麦芽品质的影响。用超声波水浴对大麦进行不同时间的处理,然后进行种子发芽试验。结果表明,超声波处理20min的种子发芽率、吸水速度、大麦表面带菌量及最终麦芽产品指标都比未经处理的对照组有了明显的提高。超声波处理能显著地促进大麦的萌发,提高种子活力及麦芽品质。     

Effect of processing on the antioxidant properties of extracts from Mexican barley (Hordeum vulgare) cultivar

The effect of traditional cooking, roasting and germination on the antioxidant capacity of a Mexican barley cultivar is presented. Barley dried grains were processed and phenolic extracts obtained by successive extractions with hexane, aqueous acetone (70%), aqueous methanol (50%) and water. Total phenolic content was evaluated by the Folin–Ciocalteu method and the radical scavenging capacity by the DPPH method. The inhibition of LDL oxidation was also determined. Results showed that cooking and roasting barley extracts increase, the total phenolic content in comparison with control (unprocessed) barley extracts, but the germination reduces it. Germinated seeds subjected to roasting, cooking and unprocessed barley grains showed a higher antioxidant activity (IC₅₀). Traditionally cooked barley grains showed the highest inhibition of LDL oxidation. These results indicate that processing affects significantly the antioxidant capacity of barley phenolic extracts.     

Effect of Humic Fractions from Urban Wastes and Other More Evolved Organic Materials on Seed Germination

The effect of different amounts of humic fractions obtained from urban wastes (sewage sludge and compost) on seed germination (barley, watercress and tobacco) has been compared with that of humic derived from more evolved organic materials (leonardite and peat) and a commercial humic acid fractions. Results demonstrated that the humic fractions from urban wastes had a more irregular effect on seed germination than those proceeding from more humified organic materials. Humic substances had a more positive effect on germination than humic acids, those effects depending on the nature of the original organic materials. The stability of the original organic materials (urban wastes or evolved organic materials) was a determinant factor of the behaviour of humic fractions on the germination process.