Extreme resistance to weak-acid preservatives in the spoilage yeast Zygosaccharomyces bailii.
Extreme resistance to weak-acid preservatives in the spoilage yeast Zygosaccharomyces bailii.
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DOI：
10.1016/j.ijfoodmicro.2013.06.025
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发表时间：
2013-08-16
影响因子：
5.4
通讯作者：
Archer DB
中科院分区：
文献类型：
--
作者：
Stratford M;Steels H;Nebe-von-Caron G;Novodvorska M;Hayer K;Archer DB
弱酸性防腐剂，如山梨酸和乙酸，用于许多低pH值食品，以防止真菌腐败。腐败酵母Zygosaccharomyces bailii因其对防腐剂的极端抗性和在超过法律允许的防腐剂浓度下生长的能力而臭名昭著。38株Z.几种弱酸性防腐剂。以酿酒酵母为对照，试验表明，Z。Bailii对各种弱酸的耐受性高约3倍，但对醇、醛、酯、醚、酮或亲水螯合酸的耐受性并不高。弱酸在化学结构上非常多样化，因此不可能由降解或代谢引起普遍的抗性。对Z. Bailii细胞群显示对山梨酸、苯甲酸和乙酸的极端抗性限于群内的少数细胞，数量随着弱酸浓度降低至< 1/1000。将抗性亚群重新接种到含弱酸的培养基中，表明所有细胞现在都具有极强的抗性。在任何弱酸性防腐剂中生长的抗性亚群对其他弱酸性防腐剂也显示出~ 100%的交叉抗性。利用14 C-乙酸的测试表明，弱酸积累的抗性亚群低得多。酸积累是由细胞质中较高pH下的酸解离引起的。对耐药亚群细胞内pH（pHi）的测试表明，pH值远低于敏感的大群，约为pH 5.6。提出了Z. bailii是由于人口异质性，与一小部分的细胞具有较低的细胞内pH值。这降低了积累的水平，任何弱酸在细胞质中，从而赋予耐药性的所有弱酸，但不是其他抑制剂。Z. bailii对弱酸的抗性是由于种群异质性所致。抗性Z. bailii亚群对所有其他弱酸都具有交叉抗性。弱酸积累是由细胞内部pH决定的。bailii亚群的内部pH值较低，约为0.6个pH单位。抗性Z. bailii亚种群吸收的14 C乙酸少3倍。
Weak-acid preservatives, such as sorbic acid and acetic acid, are used in many low pH foods to prevent spoilage by fungi. The spoilage yeast Zygosaccharomyces bailii is notorious for its extreme resistance to preservatives and ability to grow in excess of legally-permitted concentrations of preservatives. Extreme resistance was confirmed in 38 strains of Z. bailii to several weak-acid preservatives. Using the brewing yeast Saccharomyces cerevisiae as a control, tests showed that Z. bailii was ~ 3-fold more resistant to a variety of weak-acids but was not more resistant to alcohols, aldehydes, esters, ethers, ketones, or hydrophilic chelating acids. The weak acids were chemically very diverse in structure, making it improbable that the universal resistance was caused by degradation or metabolism. Examination of Z. bailii cell populations showed that extreme resistance to sorbic acid, benzoic acid and acetic acid was limited to a few cells within the population, numbers decreasing with concentration of weak acid to < 1 in 1000. Re-inoculation of resistant sub-populations into weak-acid-containing media showed that all cells now possessed extreme resistance. Resistant sub-populations grown in any weak-acid preservative also showed ~ 100% cross-resistance to other weak-acid preservatives. Tests using 14C-acetic acid showed that weak-acid accumulation was much lower in the resistant sub-populations. Acid accumulation is caused by acid dissociation in the higher pH of the cytoplasm. Tests on intracellular pH (pHi) in the resistant sub-population showed that the pH was much lower, ~ pH 5.6, than in the sensitive bulk population. The hypothesis is proposed that extreme resistance to weak-acid preservatives in Z. bailii is due to population heterogeneity, with a small proportion of cells having a lower intracellular pH. This reduces the level of accumulation of any weak acid in the cytoplasm, thus conferring resistance to all weak acids, but not to other inhibitors. Z. bailii resistance to weak acids was due to population heterogeneity. Resistant Z. bailii sub-populations were cross resistant to all other weak acids. Weak acid accumulation is determined by cell internal pH. Resistant Z. bailii sub-populations had a lower internal pH, ~ 0.6 pH units. Resistant Z. bailii sub-populations absorbed 3-fold less 14C acetic acid.
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影响因子：
6
作者：
Betts, GD;Linton, P;Betteridge, RJ
通讯作者：
Betteridge, RJ
DOI：
10.1016/b978-0-444-52149-1.00084-7
发表时间：
2011-01-01
期刊：
YEASTS: A TAXONOMIC STUDY, VOLS 1-3, 5TH EDITION
影响因子：
--
作者：
James, Stephen A.;Stratford, Malcolm
通讯作者：
Stratford, Malcolm
影响因子：
3.2
作者：
Merico, A;Capitanio, D;Compagno, C
通讯作者：
Compagno, C
影响因子：
3.6
作者：
Mollapour, M;Piper, PW
通讯作者：
Piper, PW
DOI：
10.1016/j.ijfoodmicro.2012.03.028
发表时间：
2012-06-01
影响因子：
5.4
作者：
Dang, T. D. T.;De Maeseneire, S. L.;Devlieghere, F.
通讯作者：
Devlieghere, F.