Allyl Alcohol Is the Sole Antiyeast Compound in Heated Garlic Extract

The principal antiyeast compound of heated garlic was isolated and identified by high‐performance liquid chromatography (HPLC) and gas chromatography‐mass spectrometry (GC‐MS) as allyl alcohol (2‐pro‐pene‐1‐ol). The generation of allyl alcohol was observed in heated garlic as well as in heated pure alliin solution. The pattern of growth inhibition of Candida utilis ATCC42416 by allyl alcohol was essentially the same as that seen with heated garlic and heated alliin solution. The minimum inhibitory concentrations of heated garlic, with an alliin content of 1.5% (w/v), and allyl alcohol were 0.6% (v/v) and 0.002% (v/v), respectively, against C. utilis ATCC42416. Yeasts were extremely sensitive to allyl alcohol, with minimum inhibitory concentration (MIC) ranging from 0.002% (v/v) to 0.014% (v/v), while bacteria were not very sensitive to allyl alcohol, with MIC ranging from 4% to 7%. Among yeasts, xerotolerant strains, including Zygosaccharomyces rouxii, were significantly less sensitive to allyl alcohol and heated garlic extract than others. Allyl alcohol is different from all other known antimicrobial compounds found in garlic in that it does not contain sulfur in its molecule.     

Antiyeast Activity of Heated Garlic in the Absence of Alliinase Enzyme Action

Garlic heated to 121 °C was found to strongly inhibit the growth of yeasts, but not that of bacteria. The potency and stability of the antiyeast activity of heated garlic were compared with those of fresh garlic, garlic oil, and allyl isothiocyanate. The inhibitory activity of heated garlic was stable, and the minimum inhibitory concentration did not change for up to 30 d at 37 °C. The antiyeast activity of heated garlic was not influenced by pH. Alliin heated in distilled water showed an antiyeast activity pattern similar to that of heated garlic, suggesting that the compound(s) thermally generated from alliin are the principal antiyeast compound(s) of heated garlic. The antiyeast activity was increased as time of heating increased up to 45 min at 121 °C, and the activity did not change when garlic was further heated for up to 120 min.     

高效液相色谱法测定大蒜中蒜氨酸含量

采用高效液相色谱法对大蒜中的蒜氨酸进行定性定量研究,利用微波灭酶、水煮灭酶、有机溶剂冷冻灭酶3种方法对大蒜中蒜氨酸进行提取。蒜氨酸的出峰时间为3.717min,测得蒜氨酸的含量为:0.823%、0.730%和0.156%。同时对大蒜破碎放置1d后体系中剩余蒜氨酸的含量进行了分析,测得剩余蒜氨酸含量占蒜氨酸总量的23.0%。通过向破碎的大蒜体系中添加磷酸吡哆醛(PLP),能够显著提高蒜氨酸的转化率。     

大蒜中蒜氨酸分离纯化工艺研究

以大蒜为原料,分别研究了醇沉法和葡聚糖凝胶G-10对蒜氨酸的分离纯化效果。结果表明醇沉法分离蒜氨酸的最佳工艺条件为:大蒜提取液真空浓缩至可溶性固形物含量为20%,加入乙醇至终浓度为80%,静置18 h,分离得上清液及沉淀,再将所得上清液及沉淀复溶后按上述条件分别进行醇沉,得二次醇沉上清液,合并,冷冻干燥,得蒜氨酸粗品。蒜氨酸粗品经葡聚糖凝胶G-10色谱法纯化最佳条件为:上样液浓度为30%,上样量2%柱体积,洗脱流速1 mL/min,通过葡聚糖凝胶G-10分离后,蒜氨酸的纯度可达到43.5%。     

反相高压液相色谱法测定鲜蒜中的蒜氨酸

为准确、快速、方便的测定大蒜中的蒜氨酸,采用反相高效液相色谱法(RP-HPLC),HypersilODSC18(250mm×4·6mm)色谱柱,检测波长200nm,5%甲醇+95%pH=5磷酸缓冲液为流动相,流速为0·5mL/min,柱温为20℃等条件下进行测定。测定结果为:蒜氨酸浓度与峰面积呈良好的线性关系,线性范围为10~350μg/mL;利用蒜氨酸酶反应样品的HPLC行为差异或纯蒜氨酸均可对蒜氨酸进行定性测定。测定结果表明,该方法经济、简便、快速、重现性好。     

DNFB柱前衍生RP-HPLC法测定大蒜中蒜氨酸含量

用2,4二硝基氟苯(DNFB)柱前衍生RP-HPLC法测定大蒜中蒜氨酸的含量.以DNFB为衍生试剂,60℃,pH9.0下衍生1 h,ODS色谱柱分离,乙腈-四氢呋喃-醋酸钠缓冲液为流动相洗脱,360nm检测.结果表明衍生后蒜氨酸色谱分离良好,线性范围为74～370μg/mL(r-0.9996);平均加标回收率为101.48%;RSD为1.37%(n=5);日内精密度为0.23%.结果表明方法准确、灵敏,可有效检测大蒜中蒜氨酸及其它氨基酸组分.     

Alliinase-independent Inhibition of Staphylococcus aureus B33 by Heated Garlic

ABSTRACT: Heated (121 °C) garlic extract in which alliinase was inactivated before crushing exhibited complete bacteriostatic activity at 15% against Staphylococcus aureus. Garlic heated for 45 min showed the highest antibacterial activity and the relative peak areas of 4-heptenal, methyl allyl disulfide, diallyl disulfide, 2-vinyl-4H-1,3-dithiin, and diallyl trisulfide (DATS) were highest at 45 min of heating. Other than 4-heptenal, all these compounds are known to possess different degrees of antibacterial activity. DATS was thought to be the primary antibacterial compound in heated garlic extract. It was tentatively concluded that antibacterial compounds were formed from alliin unreacted by alliinase by marked heating. Diallyl compounds with more than three sulfur atoms and the oxidized form of allicin were not detected.     

利用4-MP测定大蒜中的蒜氨酸

为快速、方便地测定大蒜中的蒜氨酸,以鲜蒜为原料,经去皮、加热、制汁、与4-巯基吡啶(4-MP)反应、324纳米测定其吸光度等处理,测知鲜蒜中蒜氨酸的含量为0.74%～0.92%,变异系数2.4%～8.8%,结果表明,4-MP比色法测定大蒜中的蒜氨酸,简单、快速、方便,可用于鲜蒜与保藏大蒜中蒜氨酸含量的测定。     

AQC柱前衍生化RP-HPLC法测定大蒜中蒜氨酸含量

建立了一种快速、可靠的检测大蒜中蒜氨酸(alliin)的方法。采用6- 氨基喹啉基-N- 羟基琥珀酰亚氨基甲酸酯(AQC)试剂,在pH8.5 的缓冲液中对大蒜中蒜氨酸进行柱前衍生,使用Waters Symetry C18 分析柱(150mm ×3.9mm,5μm),以pH5.5 的0.02mol/L 磷酸二氢钾- 乙腈 (75:25,V/V)为流动相,流速为0.8ml/min,激发波长为250nm,发射波长为395nm 时荧光检测。蒜氨酸在1～16mg/L 范围内浓度与峰面积线性关系良好,线性相关系数为0.99,检测限为1mg/L,回收率>95%。     

HPLC法测定大蒜中蒜氨酸和大蒜素的含量

建立了大蒜中大蒜素和蒜氨酸含量测定的HPLC法。结果表明:蒜氨酸的测定条件为,YMC-PackODS-A C18(25 cm×4.6 mm)色谱柱,流动相为20%甲醇,流速0.7 mL/min,检测波长214 nm;大蒜素的测定条件为,YMC-Pack ODS-A C18(25 cm×4.6 mm)色谱柱,流动相为85%甲醇,流速0.8 mL/min,检测波长214 nm;蒜氨酸和大蒜素的平均回收率分别为,89.9%±1.6%和87.2%±1.3%,精密度(RSD)分别为1.02%和1.46%;大蒜中蒜氨酸和大蒜素的含量分别为,1.67%和0.93%。     

不同加工工艺对黑蒜产品品质的影响

黑蒜是一种新型大蒜加工制品,通过不同加工工艺得到两种不同的产品黑蒜1号和黑蒜2号,其中黑蒜1号的生产周期为黑蒜2号的3倍。本研究比较了两种加工工艺对黑蒜基本营养成分、蒜氨酸含量以及自由基清除能力的影响。研究表明:与新鲜大蒜相比,黑蒜的水分含量较少约为40%,湿基中的可溶糖、蛋白质和多酚显著增多(P0.01),蒜氨酸含量减少。而干基中的营养物质除多酚外,其余成分都减少,脯氨酸和精氨酸急剧降低,变异系数分别为1.03和1.12。湿基对OH·的清除能力基本一致,对DPPH·的清除力为新鲜蒜的2倍。黑蒜1号的粗蛋白含量低于黑蒜2号,可溶糖、多酚、蒜氨酸皆高于黑蒜2号,粗蛋白和多酚变异系数达到0.20左右,各组分间存在显著差异(P0.05)。在不同浓度下对自由基清除能力相同,当浓度为0.05 g/m L时,对OH·和DPPH·的清除率达到了90%以上。电子舌可以有效的区别两种产品。     

大蒜加工中阿霍烯产生过程的研究

阿霍烯是一种高生物活性硫化物,具有预防心血管疾病等功能。在新鲜大蒜中阿霍烯的含量极少,且稳定性差。本文用新鲜大蒜中的内源酶将其加工成富含阿霍烯的"黑大蒜"制品,调查国内外12种大蒜在加工中蒜氨酸、大蒜辣素和阿霍烯含量的变化,分析各成分含量之间的定量关系,以揭示阿霍烯的产生过程。试验结果表明,蒜氨酸含量在加工中逐渐减少,并趋于平衡;大蒜辣素含量在加工前、后都较低,而加工第2天出现最大值(即最大生成量);阿霍烯含量在加工20d内随时间呈线性增加。黑大蒜制品的阿霍烯含量随大蒜辣素含量的增加呈线性增加,大蒜辣素含量随新鲜大蒜中蒜氨酸含量的增加呈线性增加,充分说明蒜氨酸经过大蒜辣素向阿霍烯的转化过程。当新鲜大蒜中蒜氨酸含量为5.94%时,黑大蒜制品中阿霍烯的含量可达新鲜大蒜的17.5倍。     

大蒜素和有机溶剂对蒜氨酸酶活性及大蒜油组成的影响

大蒜油具有重要的生物活性和调味功能。本文以化学合成的蒜氨酸为原料在蒜酶的催化下制备大蒜油,研究中间产物大蒜素、萃取溶剂对蒜酶活性的影响,以及溶剂对大蒜油组成成分的影响。结果显示:大蒜素在一定程度上会抑制蒜酶的活性,但不会导致蒜酶的完全失活;有机溶剂对蒜酶的影响比较复杂,其中氯仿、二氯甲烷使蒜酶活性完全丧失,而正己烷、正戊烷对蒜酶的活性影响则不明显。采用气质联用、核磁共振二维谱表征了不同溶剂下大蒜油的组成。用氯仿、正己烷等非极性溶剂萃取大蒜素,得到的大蒜油以3-乙烯基-1,2-二硫环己-4-烯(4X)和3-乙烯基-1,2-二硫环己-5-烯(5X)为主;而用乙酸等质子溶剂萃取,则大蒜油成分以二烯丙基三硫醚(DATS)、二烯丙基二硫醚(DADS)为主。     

氢化物原子荧光法测定大蒜及其制品中的硒

目的：测定大蒜及其制品中硒的含量。方法：大蒜、蒜氨酸、蒜酶、大蒜多糖样品经过HNO3-HClO4湿法消解,采用氢化物原子荧光光谱法测定硒的含量。结果：大蒜、蒜氨酸、蒜酶、大蒜多糖中硒的含量分别为0.010～0.024、0.423～0.629、0.057～0.064、0.001～0.007μg/g。结论：该方法测定大蒜及其制品中硒的含量,操作简便,灵敏度高。     

大蒜、生姜、洋葱醇提物抗氧化活性的比较

通过测定大蒜、生姜、洋葱醇提物的还原力、螯合能力及其对DPPH自由基、超氧阴离子自由基、羟基自由基的清除能力研究了它们的抗氧化活性。实验结果表明,大蒜、生姜、洋葱醇提物均具有较强的还原力和螯合能力,对超氧阴离子自由基、羟基自由基和DPPH自由基具有不同效果的清除作用,即大蒜、生姜、洋葱醇提物均具有显著的体外抗氧化活性,值得进一步研究开发。     

Effect of Milk on the Deodorization of Malodorous Breath after Garlic Ingestion

Abstract: The effect of milk and milk components on the deodorization of diallyl disulfide (DADS), allyl methyl disulfide (AMDS), allyl mercaptan (AM), allyl methyl sulfide (AMS), and methyl mercaptan (MM) in the headspace of garlic as well as in the mouth- and nose-space after garlic ingestion was investigated using selected ion flow tube-mass spectrometry (SIFT-MS). Fat-free and whole milk significantly reduced the head-, mouth-, and nose-space concentrations of all volatiles. Water was the major component in milk responsible for the deodorization of volatiles. Due to its higher fat content, whole milk was more effective than fat-free milk in the deodorization of the more hydrophobic volatiles diallyl disulfide and allyl methyl disulfide. Milk was more effective than water and 10% sodium caseinate in the deodorization of allyl methyl sulfide, a persistent garlic odor, in the mouth after garlic ingestion. Addition of milk to garlic before ingestion had a higher deodorizing effect on the volatiles in the mouth than drinking milk after consuming garlic. Practical Application: Ingesting beverages or foods with high water and/or fat content such as milk may help reduce the malodorous odor in breath after garlic ingestion and mask the garlic flavor during eating. To enhance the deodorizing effect, deodorant foods should be mixed with garlic before ingestion.     

Synergistic antiyeast activity of garlic oil and allyl alcohol derived from alliin in garlic

ABSTRACT:  Garlic oil (GO) and allyl alcohol (AA), both derived from alliin in garlic using different preparation methods, cause potent growth inhibition in yeasts. GO and AA inhibited Candida utilis ATCC42416 in different ways: GO has fungistatic activity while AA has fungicidal activity. GO and AA have almost identical antimicrobial potencies against the indicator yeast, with minimum inhibitory concentrations of about 25 ppm when tested individually. When GO and AA were tested in combination, the antimicrobial efficacy significantly increased. Combinations of AA and GO at 1 and 9 ppm, 2 and 7 ppm, 5 and 5 ppm, and 6 and 3 ppm, respectively, inhibited C. utilis completely. The sum of the fractional inhibitory concentrations (FICs) in the 2-component (GO and AA) combination was as low as 0.37 for C. utilis , indicating strong synergism. The sum of the FICs of diallyl disulfide and diallyl trisulfide in combination with AA was larger than that of the GO–AA combination, suggesting that the synergy was lower.     

水法提取大蒜抑菌活性物质条件优化

为优化水法提取大蒜抑菌活性物质的工艺,研究料液比、浸提时间、浸提温度、pH对水法提取抑菌活性物质的影响,并采用正交试验法优化其工艺参数.利用GC-MS对大蒜水提液中的有效物质进行鉴定.试验结果表明,水法提取大蒜抑菌活性物质的最优条件是:料液比1:3,浸提温度30℃,漫提时间30min,pH6;大蒜水漫提液中主要的活性物质为S-甲基甲烷硫代亚磺酸酯、3-乙烯基-1,2-二硫杂-4-环己烯、3-乙烯基-1、2-二硫杂-5-环已烯、二烯丙基三硫醚等.     

不同地理居群大蒜中潜在大蒜辣素的含量测定及聚类分析

以新疆境内及其他部分省市不同地理居群的25份大蒜样品为研究对象,以羟苯丁酯为内标,采用高效液相色谱法测定大蒜中潜在大蒜辣素的含量,并对含量测定结果进行聚类分析。结果表明,不同地理居群大蒜药用活性成分的含量差异明显,新疆境内天山以南阿合奇县与乌什县两大居群的大蒜样品药用活性成分含量最高,药用价值值得进一步挖掘,25份样品按照潜在大蒜辣素含量的高低可聚为5大类。     

大蒜对蔬菜亚硝酸盐消除作用的实验研究

利用溶液中的亚硝酸盐含量与其吸光度成正比的关系,采用盐酸萘乙二胺分光光度法,分别测定了芹菜、胡萝卜、油菜、西葫芦、西红柿、黄瓜六种蔬菜未加大蒜浸提液时以及添加后的亚硝酸盐含量,得出大蒜浸提液对六种蔬菜中所含的亚硝酸盐的清除率。研究了影响大蒜浸提液清除亚硝酸盐的几种因素:大蒜浸提液与亚硝酸盐的反应温度、反应时间、反应介质的pH值和反应时大蒜浸提液的用量。结果表明:物料比为1∶2的大蒜浸提液在80℃水浴下处理10min,反应液pH为4.0时对亚硝酸盐的清除率最大。将研究结果用于蔬菜中亚硝酸盐的清除,效果比较明显。