Interrelationships between a Yeast and a Bacterium when growing together in Defined Medium

Significance of microbial symbiotic coexistence in traditional fermentation

“…In contrast, in mixed cultures, yeasts would provide some nutrients to LAB, supporting bacterial growth (1). These results were easily deduced in previous studies (116). In addition, catalase produced by yeast would protect the LAB from oxidative stress (1).…”

“…In 1953, Woods pointed out the importance of the study of mixed cultures of microorganisms (115). Challinor et al reported pioneering results on the physiology of mixed cultures of LAB and yeast in 1954 (116), showing that yeast provide LAB with nicotinic acid and thiamine, which are essential for LAB growth.…”

“…VOL. 116,2013 MICROBIAL SYMBIOTIC COEXISTENCE acetaldehyde (C2 precursor) and D-xylulose-5-phosphate (C5 precursor). There are three hypothesis in HEMF biosynthesis pathway; (i) organically or inorganically synthesized from C2 precursor and C5 precursor (produced by koji mold) (46,48); (ii) organically synthesized by yeast from C2 precursor (derived from glucose) and C5 precursor (product of aminocarbonyl reaction) (48); (iii) inorganically synthesized from C2 precursor (produced by strecker degradation) and C5 precursor (product of aminocarbonyl reaction) (47).…”

Effect of substrate and cellulase concentration on simultaneous saccharification and fermentation of steam-pretreated softwood for ethanol production

“…The sensitivity of SSF to infection may be due to S. cerevisiae facilitating the growth of lactic acid bacteria (Lemaresquier, 1987;Narendranath et al, 1997), either by conversion of some of the inhibiting components or by releasing some components necessary for the growth of lactic acid bacteria. It is known that S. cerevisiae consumes furfural and HMF (Larsson et al, in press;Sanchez and Bautista, 1988) and releases substances necessary for the growth of lactic acid bacteria, such as thiamine and guanine (Challinor and Rose, 1954). We observed that the growth of bacteria increased when the glucose level was low, probably because the yeast was stressed or dying, both of which initiate the release of various substances.…”

Relações tróficas entre Saccharomyces cerevisiae e Lactobacillus sp. nas condições da fermentação alcoólica industrial

“…No entanto, nem todas as relações travadas são de antagonismo, muitas vezes a própria levedura pode estimular o crescimento da bactéria, figurando como o microrganismo ativo e sintetizando a substância ausente para o crescimento ótimo da bactéria (CHALLINOR; ROSE, 1954). Como já citado anteriormente, as bactérias láticas são exigentes nutricionalmente e crescem apenas em meios relativamente complexos, contendo aminoácidos, vitaminas, sais, ácidos graxos, carboidratos e outros (KANDLER; WEISS, 1986); dessa maneira, esses microrganismos se valem de nutrientes provenientes da levedura e de seu processo fermentativo, como aminoácidos liberados pela autólise de levedura, monossacarídeos liberados após a hidrólise da sacarose, além do etanol quando em concentrações inferiores a 2% (SELBY-SMITH et al, 1975;ESSIA-NGANG et al, 1992;KING;BEELMAN, 1986).…”