产γ-氨基丁酸的菌株筛选及鉴定

为获得产γ-氨基丁酸安全菌株,本实验从泡菜汁及酸奶液中进行定向筛选,利用薄层层析法(TLC)对其发酵物进行了初步分析,随后对其进行了16S r DNA基因测序,最后利用高效液相色谱法(HPLC)进行产物定量分析评估其生产能力。结果表明得到六株产谷氨酸脱羧酶催化L-谷氨酸脱羧生成γ-氨基丁酸的菌株,在Gen Bank中进行同源性比对后,鉴定六菌株均为植物乳酸短杆菌。定量分析六株菌发酵液中γ-氨基丁酸含量发现其产量均在200~500μg/m L之间,其中最高产量为493.3μg/m L。实验结果显示,硅胶薄层层析可以快速定性检测培养物中是否含有γ-氨基丁酸,而优化后的高效液相色谱法能准确定量检测培养物中的γ-氨基丁酸含量。筛选获得的乳酸杆菌生物安全性高,有一定应用推广前景。     

TLC和HPLC法相结合分析盐水鸭中的生物胺

应用薄层层析(TLC)和高效液相色谱(HPLC)两种方法分析盐水鸭中生物胺的组成及含量。薄层层析结果显示,盐水鸭样品中存在着腐胺、尸胺、亚精胺、精胺、酪胺和2-苯乙胺;利用高效液相色谱法也检测到了以上6种生物胺,且各生物胺的含量均在204μg/g以下。两种方法结果相吻合,TLC法可以作为肉制品中生物胺定性分析的一种经济便捷的方法。     

南瓜中内生菌筛选及其次级代谢产物的分析

目的：为充分开发利用南瓜资源,寻找生产多酚类化合物等活性物质的内生菌。方法：采用组织块分离法、划线分离法及梯度稀释法获得南瓜果肉中的内生菌,并利用平板对峙法对其抑菌活性进行测定,再以南瓜提取液为对照,对各拮抗菌株的发酵液进行薄层层析分析,然后利用高效液相色谱法作进一步检测,从而确定活性物质的种类。结果：从南瓜果肉中共分离到54 株内生菌。通过抑菌实验发现其中12 株对一种或多种指示菌具有抑菌活性,占分离菌株数的22%,其中3 株（25、26、29号）具有较广谱抑菌活性,抑菌率较高,可达（36.73±0.52）%。薄层层析检测表明：25号菌株的发酵产物在比移值（Rf）为0.57时与标准南瓜提取液斑点Rf相同。结论：25号菌株能发酵产生多酚类或类似化合物,这为利用内生菌发酵生产多酚类成分提供了新的思路和途径。     

苯乳酸的快速检测研究

苯乳酸是一种新型生物防腐剂。文中研究了苯乳酸的薄层层析快速检测方法、反相高效液相色谱分析检测法,并利用手性柱高效液相色谱分析检测D-型和L-型苯乳酸。     

丹参内生真菌产生淀粉酶菌株的筛选鉴定及酶学性质分析

目的:从丹参内生真菌中筛选耐热性强的酸性生淀粉酶菌株,并对其酶学性质进行初步研究。方法:以50株丹参内生真菌作为筛选对象,通过淀粉固体培养基初筛、液体发酵复筛,筛选产生淀粉酶活力较高的菌株;通过形态学观察和ITS序列分析对产酶菌株进行鉴定。结果:从50株丹参内生真菌中,筛选出5株产生淀粉酶活力较高的菌株,其中菌株ZDH2-2-1-1为产淀粉酶活性最强的菌株,酶活力达到117.63 U/m L,经鉴定为互隔链格孢(Alternaria alternata)。该淀粉酶最适p H为4.0,最适反应温度为55℃,具有较好的热稳定性和p H稳定性,对生淀粉具有广谱的降解能力。通过薄层层析发现,ZDH2-2-1-1所产淀粉酶的酶解产物为葡萄糖。结论:丹参内生真菌能产生高活性的耐热性酸性生淀粉酶,在生淀粉深加工中具有极大的开发潜力。     

重组α-半乳糖苷酶酶解大豆低聚糖研究

本研究应用本实验室基因重组咖啡豆α-半乳糖苷酶对棉籽糖和水苏糖进行了酶解,应用薄层层析(TLC)和高效液相色谱(HPLC)法检测了酶解前后大豆低聚糖的变化情况,结合大豆制品传统加工工艺,提出了酶的添加方式和工艺。     

橄榄叶黄酮类抗氧化物质的结构分析研究

通过超声强化提取法提取橄榄叶黄酮,采用聚酰胺柱层析和制备薄层层析对橄榄叶黄酮提取液进行分离纯化,通过抗氧化活性比较,筛选抗氧化活性最好的样品C3,运用高效液相色谱法(HPLC)、紫外光谱法(UV)、红外光谱法(IR)、液质联用法(LC-MS)、核磁共振法(1HNMR,13CNMR),对样品C3进行结构分析,确定为木犀草素。     

五株海藻次级代谢产物化学筛选

海藻是海洋中未开发完全的生物新资源,富含各种有利用价值的活性代谢产物。为了确定海藻中次级代谢产物的丰富度,该实验利用化学筛选方法（薄层层析色谱（TLC）、高效液相色谱（HPLC）、气相色谱-质谱（GC-MS））对江篱、刺麒麟菜、异枝麒麟菜、石花菜及小球藻这五株海藻中的次级代谢产物进行初步筛选。结果表明,通过薄层层析色谱和高效液相色谱分析得出江蓠和石花菜显色明显,代谢产物丰富且易于提取分离。通过气相色谱-质谱分析色谱分析得出,石花菜、小球藻的石油醚相成分复杂,未知化合物较多,特别是石花菜和小球藻可以进行重点研究,为后续海藻活性代谢产物研究与应用上的研发提供有力的实验基础。     

产海藻糖合酶嗜热菌的筛选

采用薄层层析及高效液相色谱对酶反应产物进行分析的方法,从地热水样中筛选出一株产胞内海藻糖合酶的嗜热菌CBS-01菌株。该菌株在固体培养基中细胞为杆状,在液体培养基中细胞通常为丝状,丝状体长度可变,好氧,革兰氏染色阴性,无芽孢,菌落呈圆形,表面光滑,凸起,边缘整齐,暗红色,生长温度范围为40～70℃,最适生长温度为55～60℃,生长pH范围为6.5～9.5,最适生长pH值为7.5～8.5,初步鉴定为亚栖热菌(Meiothermus sp.)。     

产赤藓糖醇菌株的筛选与鉴定

利用含有300g/L 葡萄糖的高渗培养基从蜂蜜、花粉、土壤等样品中筛选耐高渗酵母菌,经薄层层析和高效液相色谱分析得到两株产赤藓糖醇且不产甘油的酵母菌,通过高碘酸氧化法筛选出其中赤藓糖醇产量较高的一株菌株E54。菌株E54 在含葡萄糖200g/L、酵母膏5g/L 的发酵培养基中发酵90h,赤藓糖醇产量为41.1g/L,转化率为22.8%。通过形态观察、生理生化实验、5.8S rDNA 序列分析并构建系统进化树,初步鉴定E54 为Moniliellaacetoabutans(丛梗孢酵母)。     

Facile on-site detection of substituted aromatic pollutants in water using thin layer chromatography combined with surface-enhanced Raman spectroscopy

A novel facile method for on-site detection of substituted aromatic pollutants in water using thin layer chromatography (TLC) combined with surface-enhanced Raman spectroscopy (SERS) was explored. Various substituted aromatics in polluted water were separated by a convenient TLC protocol and then detected using a portable Raman spectrometer with the prepared silver colloids serving as SERS-active substrates. The effects of operating conditions on detection efficacy were evaluated, and the application of TLC-SERS to on-site detection of artificial and real-life samples of aromatics/polluted water was systematically investigated. It was shown that commercially available Si 60-F(254) TLC plates were suitable for separation and displayed low SERS background and good separation efficiency, 2 mM silver colloids, 20 mM NaCl (working as aggregating agent), 40 mW laser power, and 50 s intergration time were appropriate for the detection regime. Furthermore, qualitative and quantitative detection of most of substituted aromatic pollutants was found to be readily accomplished using the developed TLC-SERS technique, which compared well with GC-MS in terms of identification ability and detection accuracy, and a limit of detection (LOD) less than 0.2 ppm (even at ppb level for some analytes) could be achieved under optimal conditions. The results reveal that the presented convenient method could be used for the effective separation and detection of the substituted aromatic pollutants of water on site, thus reducing possible influences of sample transportation and contamination while shortening the overall analysis time for emergency and routine monitoring of the substituted aromatics/polluted water.     

Trigonellin in Bohnenkaffee

Determination of trigonelline in several green and roasted coffees by thin-layer (TLC) and high-performance liquid chromatography (HPLC) were compared. Using TLC, two methods of detection were also compared. In addition, caffeine could be determined using HPLC. The determinations were each made with several variations of extraction and clean-up. Recoveries, variation coefficients and detection limits are listed. The most suitable method was HPLC in connection with hot water extraction. Only water is required as the mobile phase. The values for precision are in most cases better than (trigonelline) or similar to (caffeine) those reported in the literature. The determination of trigonelline by TLC, followed by extraction and photometry, is possible with a similar precision, but the simultaneous determination of caffeine was not tested.     

食用油脂中矿物油的定性检测方法研究

研究了皂化法、薄层色谱法及棒状薄层色谱-氢火焰离子化检测器(TLC-FID)法检测食用油脂中的矿物油。结果表明:皂化法简便、快捷,最低检测限可达0.5%,但不适用于本身含蜡质的食用油脂(如米糠油、玉米油及葵花油等);薄层色谱法(TLC)同样可对食用油脂中的矿物油进行定性检测,最低检测限可达到0.2%左右,但仍不适用于本身含蜡质的食用油脂;TLC-FID法克服了以上两种方法的缺陷,不仅适用于本身不含蜡质的食用油脂,还可对本身含蜡质的食用油脂进行矿物油的定性检测,不会出现误检,相比之下更具有优越性。     

Mycotoxin production by Penicillium expansum on blackcurrant and cherry juice.

The production of mycotoxins and other secondary metabolites by Penicillium expansum on blackcurrant and cherry juice has been studied at 10 degrees C and 25 degrees C under storage imitated conditions. P. expansum was able to synthesize extracellular patulin under all conditions, and together with extracellular chaetoglobosin A when unlimited oxygen was available. Patulin, the chaetoglobosins A and C, the communesins A and B and the expansolides A and B could be detected intracellularly depending on the conditions. The metabolites were detected using thin-layer chromatography and high-performance liquid chromatography with diode array detection by comparison to standards. A method to detect the expansolides A and B by TLC was developed.     

Passive sampling screening method using thin-layer chromatography plates

An in situ solid-phase extraction method, thin-layer chromatography (TLC) passive sampling, was investigated as a screening method for determining the presence of organic compounds in water using laboratory experiments and field applications. The TLC passive sampler developed in this research enables the spatial and temporal distributions of organic compounds to be determined qualitatively with little expense. The materials for the sampler developed here cost dollar 1.60 each. By first identifying the areas where a pollutant is present using the TLC passive sampling screening method, total analytical costs for monitoring programs may be reduced by eliminating unnecessary conventional analyses for locations where the pollutant is not present. Two organophosphorus pesticides, diazinon and chlorpyrifos, were used as a model for the development and as a potential application of the TLC passive sampling method. Passive sampler adsorption kinetics, enrichment factors, and extraction efficiencies were determined from batch experiments with exposure times ranging from 1 h to 4 weeks. In field applications, TLC passive sampling was conducted in natural and engineered systems with two silica gel extraction media, C2 and C18. Diazinon and chlorpyrifos were detected by analyzing the adsorbed compounds by high-performance liquid chromatography with ultraviolet detection.     

仿刺参共附生真菌Aspergillus terreus来源的聚酮类化合物的研究

海参是海洋中重要的食物和药物资源,含有丰富的活性物质。海参共附生微生物非常丰富。为了从海参共附生微生物获得具有强生物活性的物质,对山东芝罘岛海域的仿刺参来源的共附生真菌Aspergillus terreus利用分子生物学手段进行了种属鉴定,并利用固体基进行培养,对其次级代谢产物进行了研究。通过薄层层析、柱层析、高效液相色谱对其化学成分进行了分离和纯化,综合核磁波谱、质谱对其进行结构鉴定。从该菌中获得dihydrogeodin(1)、Territrems A(2)、Territrems B(3)、2,4-二羟基苯乙酮(4)、questin(5)和emodin(6)六种物质。利用人口腔上皮癌细胞株(KB)和多药耐药性的细胞株(KBv200)对1,5和6进行了细胞毒活性测试。本研究首次对化合物1进行了完整的谱图解析,并首次发现海洋环境来源的微生物可以代谢化合物dihydrogeodin(1),以及具有强抑制乙酰胆碱酶活性Territrems(3),而这些物质是海参本体不能够产生的,为开发具有预防和治疗帕金森病相关的功能食品提供了新来源。     

仿刺参共附生真菌 Aspergillus terreus 来源的聚酮类化合物的研究

海参是海洋中重要的食物和药物资源,含有丰富的活性物质。海参共附生微生物非常丰富。为了从海参共附生微生物获得具有强生物活性的物质,对山东芝罘岛海域的仿刺参来源的共附生真菌Aspergillus terreus利用分子生物学手段进行了种属鉴定,并利用固体基进行培养,对其次级代谢产物进行了研究。通过薄层层析、柱层析、高效液相色谱对其化学成分进行了分离和纯化,综合核磁波谱、质谱对其进行结构鉴定。从该菌中获得dihydrogeodin（1）、TerritremsA（2）,TerritremsB（3）、2,4-二羟基苯乙酮（4）、questin（5）和emodin（6）六种物质。利用人口腔上皮癌细胞株（KB）和多药耐药性的细胞株（KBv200）对1,5和6进行了细胞毒活性测试。本研究首次对化合物1进行了完整的谱图解析,并首次发现海洋环境来源的微生物可以代谢化合物dihydrogeodin（1）,以及具有强抑制乙酰胆碱酶活性Territremsf3）,而这些物质是海参本体不能够产生的,为开发具有预防和治疗帕金森病相关的功能食品提供了新来源。     

Effects of Extraction and Purification Methods on Degradation Kinetics and Stability of Lycopene from Watermelon under Storage Conditions

Lycopene was extraction, isolation and purification using recrystallization, column chromatography, and preparative thin layer chromatography (TLC) methods as well as degradation kinetics of lycopene were studied at refrigerated temperature and room temperature for 3 wk from watermelon. Higher lycopene degradation was observed at refrigerated temperature as compared to ambient temperature throughout the storage periods. The highest amount of lycopene retained in recrystallization (101.69 μg/g) followed by column chromatography (18.20 μg/g) and preparative TLC (15.57 μg/g). Color parameters, half‐life time (t_1/2), and color retention (%R) were dependent on extraction, isolation, and purification methods and storage life. Recrystallization and preparative TLC were followed by first order reaction model. Preparative TLC exhibited higher activation energy than did the recrystallization and column chromatography. Therefore, the result shows that recrystallization method could apply to extract and purify lycopene from watermelon that would also be used as a natural colorant as well as value‐added product.     

由马铃薯淀粉制得磷酸寡糖的定性定量测定

对以马铃薯淀粉为原料、全酶法制得的磷酸寡糖进行定性定量分析。通过采用薄层层析法(thin layer chromatography,TLC)和高效阴离子交换色谱-脉冲安培检测(high-performance anionic exchange chromatography-air pulsing ampere detectors,HPAEC-PAD)对磷酸寡糖组分进行检测分析,同时利用红外吸收光谱(infrared spectroscopy,IR)对其进行结构分析。结果表明：磷酸寡糖是结合有磷酸基团的并且聚合度在3～7之间的麦芽低聚糖混合物,以麦芽三糖至麦芽六糖组分居多。     

薄层色谱法测定油脂中极性化合物含量

油脂在高温条件下发生水解、氧化、聚合反应会生成各种挥发性和不挥发性极性化合物。测定极性化合物含量的传统方法是柱层析法,此法操作繁琐,时间长且无法在油脂加工过程中直接使用。实验探索性地运用薄层色谱法,利用特定指示剂在各种高温氧化油脂中的比移值的不同测定油脂中的极性化合物含量。