作者机构：
[韩文凤] Jianhu College, Zhejiang Industry Polytechnic College, Shaoxing, 312000, China;[周迎春] Luohe Customs of the People's Republic of China, Luohe, 462000, China;[谭兴和] College of Food Science and Technology, Hunan Agricultural University, Changsha, 410128, China
关键词：
cyclophosphamide;pectin;water;animal;chemistry;Citrus;drug effect;human;immunology;immunosuppressive treatment;Institute for Cancer Research mouse;intestine flora;mouse;Animals;Citrus;Cyclophosphamide;Gastrointestinal Microbiome;Humans;Immunosuppression;Mice;Mice, Inbred ICR;Pectins;Water
摘要：
<jats:title>Summary</jats:title><jats:p>The robust cell wall structure of <jats:italic>Haematococcus pluvialis</jats:italic> (<jats:italic>H.pluvialis</jats:italic>) consists of polysaccharides and tough non‐hydrolysable sporopollenins, which makes it difficult to extract superpotent antioxidant, astaxanthin from these cells. Therefore, breakdown of cell wall is a key step in the overall process of astaxanthin recovery. In this study, the mechanism of three well‐established chemical techniques for cell disruption of <jats:italic>H.pluvialis</jats:italic> cysts [ionic liquids (IL), hydrochloric acid (HCl) and multiple enzymes (multi‐enzyme, ME)] on deconstruction of the cyst cell wall of <jats:italic>H.pluvialis</jats:italic> was explored and characterised by Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), nuclear magnetic resonance (NMR) and gas chromatography–mass spectrometry (GC‐MS) analyses. The results demonstrated that the three cell wall breakdown techniques exhibited high extraction efficacies for the recovery of astaxanthin from <jats:italic>H.pluvialis</jats:italic> [IL (86.71±2.06%), HCl (80.52±2.28%) and ME (71.08±2.49%)]. However, their performances on disrupting the trilayered cell walls of <jats:italic>H.pluvialis</jats:italic> were significantly different, which were confirmed by distinct morphologies of the treated cell walls visualised by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Meanwhile, the results of FTIR confirmed that, to some extent, cellulose, hemicellulose and lignin in the cell walls were hydrolysed by HCl, IL and ME treatments. However, ME exhibited a less hydrolytic effect on lignin than HCl and IL. Moreover, XRD and NMR analyses implied that the amorphous region of cell wall was susceptible to hydrolysis/breakdown by the three techniques.</jats:p>
作者机构：
[陈剑兵; 谭兴和] College of Food Science and Technology, Hunan Agricultural University, Changsha;410128, China;[夏其乐; 曹艳] Institute of Food Science, Zhejiang Academy of Agricultural Sciences, Key Laboratory of Fruits and Vegetables Postharvest and Processing Technology Research of Zhejiang Province, Hangzhou;310021, China;[陈剑兵] 410128, China <&wdkj&> Institute of Food Science, Zhejiang Academy of Agricultural Sciences, Key Laboratory of Fruits and Vegetables Postharvest and Processing Technology Research of Zhejiang Province, Hangzhou
通讯机构：
College of Food Science and Technology, Hunan Agricultural University, Changsha, China
作者机构：
[罗思媛; 张琳娜; 何蕾] College of Food Science and Technology, Hunan Agricultural University, Changsha, 410128, China;Hunan Provincial Key Laboratory of Food Science and Biotechnology, Changsha, 410128, China;[郭红英; 王锋; 谭兴和] College of Food Science and Technology, Hunan Agricultural University, Changsha, 410128, China<&wdkj&>Hunan Provincial Key Laboratory of Food Science and Biotechnology, Changsha, 410128, China
通讯机构：
College of Food Science and Technology, Hunan Agricultural University, Changsha, China
作者机构：
[郭红英; 姚荷; 刘楚岑; 王锋; 周红丽; 谭兴和; 刘宗敏] College of Food Science and Technology, Hunan Agricultural University, Changsha, 410128, China;[严钦武; 徐永兵] Hunan Chaqi Vegetables Industry Co. Ltd., Yueyang, 414000, China;[王栏树] Hunan Jiayan Food Co. Ltd., Changsha, 410000, China
关键词：
植物乳杆菌;发酵;萝卜干;亚硝酸盐;品质
摘要：
为加快发酵速率,降低产品亚硝酸盐含量,并提高产品品质,本研究以萝卜干为原料,分别接种植物乳杆菌L4(Lactobacillus plantarum L4)和植物乳杆菌B5(L. plantarum B5),并以自然发酵为对照,萝卜干发酵时间为56 d,研究L4和B5对萝卜干品质的影响。结果表明:L4、B5和自然发酵pH值降低的速率依次为: L4>B5>自然发酵。亚硝酸盐含量随着发酵时间的延长先增加后减小,其中L4发酵在22 d左右出现亚硝酸盐峰,峰值为(3.23±0.17)mg/kg,B5和自然发酵在33 d左右出现亚硝酸盐峰,峰值分别为(2.04±0.12)mg/kg和(3.79±0.25)mg/kg(P<0.05)。挥发酯含量、游离氨基酸含量都随着发酵时间的延长呈上升趋势。L*、b*随着发酵时间的延长呈下降趋势,而a*随着发酵时间的延长呈上升趋势。发酵结束时,L4、B5和自然发酵感官评分别为88.7±2.56、81.8±1.49和74.1±3.88。由此表明,植物乳杆菌L4和B5可以缩短萝卜干的发酵周期,提高萝卜干安全性和品质,其中L4表现比B5好。
期刊：
现代食品科技,2017年33(2):123-128 and 93 ISSN：1673-9078
通讯作者：
Tan, X.-H.
作者机构：
[欧阳燕林; 王锋; 谭兴和; 郭红英; 张春艳; 张喻] Hunan Provincial Key Laboratory of Food Science and Biotechnology, College of Food Science and Technology, Hunan Agricultural University, Changsha, 410128, China
通讯机构：
Hunan Provincial Key Laboratory of Food Science and Biotechnology, College of Food Science and Technology, Hunan Agricultural University, Changsha, China
摘要：
Radiation pretreatment of lignocellulosics has been widely applied for the breakdown of the stubborn cellulose structure to enable the cellulose to be more accessible to cellulolytic enzymes. However, the effects of gamma irradiation on the lignocellulosics structure changes and the composition of pretreatment degradation products are not well understood. In this study, the influences of irradiation dose on the microstructure and irradiated-degradation components of cellulose under Co-6 gamma-irradiation (0-1200 kGy) was comprehensively investigated using giant reed and Chinese silvergrass as model substrate. The microstructure of biomass was examined with Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Additionally, composition determination and degradation products were analyzed. FT-IR analysis show that irradiation destroyed the glycosidic bond and inter- and intramolecular hydrogen bond of cellulose. XRD and SEM analyses confirm that irradiation could damage the crystalline microstructure and surface morphology of lignocellulosics. Ion chromatography analysis demonstrates that there exist fermentation sugars such as glucose, xylose, arabinose, galactose and cellobiose. Moreover, some potential inhibitors, such as glucuronic acid, galacturonic acid, methanoic acid, acetic acid, furfuraldehyde and p-coumaric acid, were detected in the irradiation-derived degradation products. Irradiation dose exhibited obvious influences on the production of these products. These investigations would be helpful for further understanding the applications and fundamentals of gamma irradiation pretreatment for bioethanol production from lignocellulosics. (c) 2016 Elsevier B.V. All rights reserved.
