1、本科毕业英语文献翻译二氧化氯相关文献Production and stability of chlorine dioxide in organic acid solutions asaffected by pH, type of acid, and concentration of sodium chlorite, and itseffectiveness in inactivating Bacillus cereus spores有机酸溶液中的二氧化氯在不同pH值、酸的种类和亚氯酸钠浓度下的生产和稳定性及其在灭活蜡状芽孢杆菌孢子时的有效性作者：Hoikyung Kima ，Youngjee
2、Kanga，Larry R. Beuchatb，Jee-Hoon Ryua，* a.Graduate School of Life Sciences and Biotechnology, Korea University, Anam-dong, Sungbuk-gu, Seoul 136-701, Republic of Korea韩国首尔136-701亚南洞Sungbuk区高丽大学生命科学与生物技术研究生院 b.Center for Food Safety and Department of Food Science and Technology, University of Georgia
3、, 1109 Experiment Street, Griffin, GA 30223-1797, USA美国GA30223-1797格里芬1109实验街佐治亚大学食品安全中心食品科学与技术部ARTICLE INFO 文章信息Article history: 文章历史Received 20 March 2008 2008年3月20号接收Accepted 23 May 2008 2008年5月23号接受Available online 28 May 2008 2008年5月28号网上可见Keywords: 关键词Chlorine dioxide 二氧化氯Organic acid 有机酸Bacil
4、lus cereus 蜡状芽孢杆菌ABSTRACT 摘要We studied the production and stability of chlorine dioxide (ClO2) in organic acid solutions and its effectiveness in killing Bacillus cereus spores.Sodium chlorite (5000, 10,000, or 50,000ug/ml) was added to 5% acetic, citric, or lactic acid solution, adjusted to pH 3.0,
5、 4.0, 5.0, or 6.0, and held at 21 for up to 14 days. The amount of ClO2 produced was higher as the concentration of sodium chlorite was increased and as the pH of the acid solutions was decreased. However, the stability in production of ClO2 was enhanced by increasing the pH of the organic acid solu
6、tions. To evaluate the lethal activity of ClO2 produced in various acid solutions as affected by acidulant and pH, suspensions of B. cereus spores were treated at 21 for 1, 3, 5, or 10 min in hydrochloric acid or organic acid solutions (pH 3.0, 4.0, 5.0, or 6.0) containing ClO2 at concentrations of
7、100, 50, or 25 ug/ml. Populations of viable spores treated with ClO2 at concentrations of 100 or 50 ug/ml in organic acid solutions decreased more rapidly than populations treated with the same concentrations of ClO2 in HCl . Rates of inactivation tended to increase with higher pH of ClO2 solutions.
8、 Results show that ClO2 formed in organic acid solutions has higher stability and is more lethal to B. cereus spores than ClO2 formed at the same concentration in HCl solution. This finding emphasizes the benefits of using organic acid solutions to prepare ClO2 intended for use as an antimicrobial.
9、我们研究了二氧化氯在有机酸溶液中的生产和稳定性以及其在杀灭蜡状芽胞杆菌孢子方面的有效性。将亚氯酸钠（5000,10000或50000微克/毫升）加入到5%的醋酸、柠檬酸或乳酸溶液中，调节pH 至3.0,4.0,5.0或6.0，保持2114天。二氧化氯含量随着亚氯酸钠浓度的增加及酸溶液pH值的减小而增加。但是生产二氧化氯的稳定性随着有机酸溶液pH值的增加而得到了加强。将蜡状芽胞杆菌孢子悬浮液分别置于含二氧化氯浓度为100ug/l，50ug/l，25ug/l，温度为21的盐酸溶液或有机酸溶液（pH为3.0,4.0,5.0,6.0）中分别放置1min,3min,5min,10min，以用来评价不同酸
10、性溶液中二氧化氯在酸化剂及pH影响下的致命性。用含二氧化氯浓度为100ug/ml或50ug/ml 的有机酸溶液处理比用相同二氧化氯浓度下的盐酸溶液处理后存活孢子的数量更易迅速下降。灭活率一般随着二氧化氯溶液pH值的增大而增大。实验表明，有机酸溶液中的二氧化氯比相同浓度下盐酸溶液中的二氧化氯有更好的稳定性且对蜡状芽孢杆菌孢子有更强的致命性。这一发现强调了用有机酸溶液制备抗菌性二氧化氯的优点。1.Introduction 前言 Aqueous chlorine dioxide (ClO2) has been approved as a disinfectant for beverage bottl
11、ing plants and food processing, handling, and storage plants ( US Environmental Protection Agency, 2007) and as a sanitizer for food processing equipment ( US Food and Drug Administration, 1977). Because of its bactericidal activity over a wide pH range, rapid biocidal action ( Bernarde et al., 1965
12、, 1967 ; McGuire and Dishinger, 1984; Rav-Acha, 1984), and limited reactions with organic materials ( Richardson et al., 1994 ; Long et al., 1999 ), gaseous or aqueous ClO2 has been effectively used to kill Escherichia coli O157:H7, Enterobacter sakazakii , Listeria monocytogenes, vegetative cells a
13、nd spores of Bacillus cereus, and spores of B. thuringiensis (Han et al., 2001; Singh et al., 2002 ; Beuchat et al., 2004 ; Rodgers et al., 2004 ; Ryu and Beuchat, 2005 ; Kim et al., 2006). One of the disadvantages of ClO2 as a sanitizer, however, is its instability during production and storage. Be
14、cause of its low stability in production, ClO2 should be prepared on site and cannot be stored for long periods of time. 二氧化氯水溶液已被批准可以作为饮料装瓶厂和食品加工厂、处理厂、储存厂（2007年美国环境保护局）以及食品加工器械（1977年美国食品和药物管理局）的消毒剂。由于二氧化氯在较宽pH范围内的杀菌活性、快速的杀菌作用（Bernarde等，1965年，1967年；McGuire ， Dishinger，1984年；Rav-Acha，1984年）以及与有机原料很少有
15、副反应（Richardson等，1994年；Long等，1999年），气体二氧化氯或二氧化氯溶液已被有效应用于杀灭大肠杆菌、阪崎肠杆菌、李斯特菌、营养细胞、蜡状芽孢杆菌孢子以及苏云金芽孢杆菌孢子（Han等，2001年；Singh等，2002年；Beuchat等，2004年；Rodgers等，2004年；Ryu ，Beuchat，2005年；Kim等，2006年）。但是二氧化氯作为消毒杀菌剂有一个缺点，即它在生产和储存过程中的不稳定性。由于二氧化氯在生产过程中的不稳定性，它需要现配现用且不能长时间储存。 One of the traditional methods to produce aque
16、ous ClO2 uses sodium chlorite (NaClO2) and hydrochloric acid (HCl) as a reaction mixture (Marriott and Gravani, 2006): 一种制备二氧化氯水溶液的传统方法是用亚氯酸钠与盐酸混合反应（Marriott ，Gravani，2006年）： 5NaClO2 +4HCl4ClO2 + 5NaCl +2H2O The amount of ClO2 formed reaches maximum concentration through rapid dissociation of HCl. I
17、f HCl were to be substituted by organic acids, which have significantly lower dissociation rates, a persistent production of ClO2 would be possible and enhanced stability could be achieved. Even though HCl is commonly used to produce ClO2 ，the acid itself may not contribute substantially to lethal a
18、ctivity because it needs to be present in an undissociated form to kill microorganisms (Asensi et al., 1997 ). The proposed mechanism of action of acids in causing the death of microorganisms is that undissociated forms diffuse across the bacterial membrane into the cell, dissociate inside the cell,
19、 and decrease the internal pH (Bearson et al., 1997; Russel and Diez-Gonzalez,1998). Acetic acid, citric acid, and lactic acid have been reported to effectively reduce large populations of E. coli O157:H7 and Salmonella ( Ryu et al., 1999; Jung and Beuchat, 2000; Harris et al., 2006). Organic acid-b
20、ased ClO2 solutions may, therefore, have greater synergistic antimicrobial activity than HCl-based ClO2 because they contain both ClO2 and undissociated forms of the acids. 随着HCl的快速分解生成的二氧化氯达到了最大浓度。如果用具有较低分解率的有机酸代替盐酸，则二氧化氯可持续产生且具有较好的稳定性。尽管HCl常被用来生产二氧化氯，但是它本身并未对微生物有致命性，因为它只有在解离的情况下才能杀灭微生物（Asensi等，199
21、7年）。酸使微生物致死的拟议的机制是这样的：离解形态的酸通过细菌细胞膜扩散至细胞内部，在细胞内分解，使内部pH值减小（Bearson等，1997年；Russel ，Diez-Gonzalez，1998年）。报道显示醋酸、柠檬酸和乳酸可有效减少大肠杆菌和沙门氏菌的数量（Ryu等，1999年；Jung ，Beuchat，2000年；Harris等，2006年）。二氧化氯的有机酸溶液既含有二氧化氯又含有离解形态的酸，因此，二氧化氯的有机酸溶液可能比二氧化氯的盐酸溶液有更强的杀菌活性。 Bacillus cereus is a Gram-positive spore former that can c
22、ause foodborne illness by producing emetic and diarrheal toxins ( Granum, 2007 ). Bacterial spores have substantial resistance to environmental stresses as compared to vegetative cells to heat, irradiation, desiccation, extreme pH, high pressure, and sanitizers ( Setlow, 2000; Atrih and Foster, 2002
23、; Young and Setlow, 2003;Beuchat et al., 2004; Cortezzo et al., 2004; Granum, 2007 ). Because B. cereus spores have significant resistance to sanitizers, including chlorine, ClO2, and peroxyacetic acid ( Foegeding et al., 1986; Beuchat et al., 2004 ; Ryu and Beuchat, 2005), there are concerns about
24、the control of B. cereus in food processing plants.The objectives of the study were to produce ClO2 using organic acids and sodium chlorite, determine its stability in production during production and storage, and evaluate its lethal activity against B. cereus spores. 蜡状芽孢杆菌是一种革兰氏阳性芽孢前，它可以通过产生呕吐和腹泻的
25、毒素引起食源性疾病（Granum，2007年 ）。相比营养细胞，细菌孢子对热、放射、干燥、极端的pH值、高压、杀菌剂等环境压力具有强大的抗性（Setlow，2000年； Atrih ，Foster， 2002年； Young ，Setlow，2003年；Beuchat 等，2004年； Cortezzo 等，2004年； Granum，2007年）。因为蜡状芽孢杆菌孢子对包括氯气、二氧化氯、过氧乙酸在内的消毒杀菌剂具有很强的抗性（Foegeding等，1986年； Beuchat 等，2004 年； Ryu，Beuchat， 2005年），所以人们对蜡状芽孢杆菌在食品加工工厂中的控制表示担忧。
26、本研究的目的是用有机酸和亚氯酸钠制备二氧化氯 ，研究生产和存储过程中二氧化氯的稳定性以及评价它对蜡状芽孢杆菌孢子的致死性。 2.Materials and methods 2.1. Production and stability of organic acid-based ClO22.1. 1 Production of ClO2 using organic acid2. 材料与方法2.1. 有机酸二氧化氯的生产和稳定性2.1.1. 用有机酸生产二氧化氯 Acetic, citric, and lactic acid solutions (200 ml, 5%, w/v) were prep
27、ared by adding appropriate amounts of acetic acid (99.7%; w/v, Biosesang, Korea), citric acid (98%, w/w; Wako, Japan), andlactic acid (7981%; w/v, Fluka, Japan) to distilled water. The pH of each acid solution was adjusted to 3.0, 4.0, 5.0, or 6.0 using 10 N sodium hydroxide. An appropriate amount o
28、f sodium chlorite (80%; Sigma-Aldrich, St. Louis, MO) was added to make concentrations of 5000, 10,000, or 50,000 ug/ml in each organic acid solution. Solutions were secured on a rotary shaker (HB-203L; Hanbaek Scientific Co., Seoul, Republic of Korea) and agitated at 150 rpm in a chemical hood for
29、14 days at 211 . 醋酸、柠檬酸和乳酸混合溶液（200 ml, 5%, w/v）是通过将适量的醋酸（99.7%；w/v， Biosesang，Korea）、柠檬酸（98%, w/w; Wako, Japan）和乳酸（7981%; w/v, Fluka, Japan）加入到蒸馏水中制得的。用10N氢氧化钠调节各酸溶液的pH至3.0 , 4.0 , 5.0 , 6.0。将适量亚氯酸钠（80%; Sigma-Aldrich, St. Louis, MO）加入各有机酸溶液中制得浓度分别为5000, 10000, 和50000 ug/ml的溶液。将溶液保存在旋转式摇床上（HB-203L;
30、韩国首尔Hanbaek 科技有限公司）以150 rpm的速度摇晃，于211 下在化学通风橱中放置14天。2.1.2. Measurement of ClO2 concentrationDuring the storage period, the amount of ClO2 formed was measured at 24-h intervals using a chlorine colorimeter (model Dr/820; Hatch, Loveland, CO).2.1.2. 二氧化氯浓度的测定 在储存期间，每隔24小时用余氯比色计（Dr/820型; Hatch, Lovelan
31、d, CO）测定一次形成的二氧化氯量。2.2. Efficacy of organic acid-based ClO2 in inactivating B. Cereus spores2.2.1. Preparation of B. cereus spores in suspension2.2. 有机酸二氧化氯在灭活蜡状芽孢杆菌孢子方面的效用2.2.1. 蜡状芽孢杆菌孢子悬浮液的制备 B. cereus strain 038-2, a diarrheal and emetic isolate, was obtained from Dr. S. Doores, Pennsylvania Stat
32、e University, University Prk, PA. This strain had been isolated from infant formula. Spores of the bacterium were collected as modified from the method used by Kreske et al. (2006). The strain was grown in tryptic soy broth (TSB; BBL/Difco, Sparks, MD) at 30for 24 h. The culture was transferred by loop inoculation (ca. 10ul) three times at 24-h intervals, surface plated on tryptic soy agar (TSA; BBL/Difco), and incubated at 30for 72 h. Cells were observed under light microscopy to confirm that99% of the cells had sporulated. Colonies from several plates were harvested using a s
