Lactic acid bacteria Lactobacillus

Mira de Orduna, R., Patchett, M.L., Liu, S.-Q., Pdone, G.l. (2001). Growth and arginine metabolism of the wine lactic acid bacteria Lactobacillus buchneri and Oenococcus oeni at different pH values and arginine concentrations. Appl. Environ. Microbiol., 67, 1657-1662. 

Marcobal, A., Martin-Alvarez, P.J., Moreno-Arribas M.V, Munoz, R. (2006a). A multifactorial design for studying factors influencing growth and tyramine production of the lactic acid bacteria Lactobacillus brevis CECT 4669 and Enterococcus faecium BIFI-58. Res. Microbiol, 157, 417-424. 

It is worth mentioning a couple of special bread types produced by non-traditional fermentations. A well-known example is the San Francisco sour dough bread. This bread type accounts for more than 20% of the bread sales in the San Francisco Bay area (Sugihara, 1977). The sourdough fermentation is based on a highly specialised co-operation between the yeast Candida holmii and the lactic acid bacteria Lactobacillus sanfran-cisco (Sugihara, 1977). 

Lactic acid bacteria Lactobacillus casei Shirota [30 L. acidophilus CK92 and L. helveticus CK60 [7] Bifidobactehum lactis Bb-12 [7] ... 

Yeast and culture starter Lactobacillus bulgaricus Lactic acid bacteria Cheese and yoghurt production... 

Sugar is transformed and reduced to glycerol during fermentation with LactobadUvs mannitopoeus or Lactobacillus lycopersici (heterofer-mentative lactic acid bacteria). This conversion, which has been described by different investigators, may be formulated as follows ... 

Simple organic molecules Ethanol Butanol Acetone Acetic acid Lactic acid Saccharomyces cerevisiae Pachysolen tamiophilus, some Clostridium spp. Clostridium acetobutylicum, C. saccharoacetobutylicum Clostridium acetobutylicum, C. saccharoacetobutylicum Various acetic acid bacteria Lactobacillus spp. 

Lactose is readily fermented by lactic acid bacteria, especially Lactococcus spp. and Lactobacillus spp., to lactic acid, and by some species of yeast, e.g. Kluyveromyces spp., to ethanol (Figure 2.27). Lactic acid may be used as a food acidulant, as a component in the manufacture of plastics, or converted to ammonium lactate as a source of nitrogen for animal nutrition. It can be converted to propionic acid, which has many food applications, by Propionibacterium spp. Potable ethanol is being produced commercially from lactose in whey or UF permeate. The ethanol may also be used for industrial purposes or as a fuel but is probably not cost-competitive with ethanol produced by fermentation of sucrose or chemically. The ethanol may also be oxidized to acetic acid. The mother liquor remaining from the production of lactic acid or ethanol may be subjected to anaerobic digestion with the production of methane (CH4) for use as a fuel several such plants are in commercial use. 

Figure 10.12 Metabolism of lactose by lactic acid bacteria many Lactobacillus species/strains can not metabolize galactose (from Cogan and Hill, 1993).

When grown in alkaline media, certain species of lactic acid bacteria decrease production of LDH, resulting in increased formation of formate, acetate, and ethanol as end products. This phenomenon has been observed in S. faecalis subsp. liquefaciens (Gunsalus and Niven 1942), Streptococcus durans, S. thermophilus, (Platt and Foster 1958), and Lactobacillus bulgaricus (Rhee and Pack 1980). Data of Rhee and Pack (1980) indicate that a phosphoroclastic split of pyruvate occurs under alkaline conditions to yield ATP. The enzymes involved in this reaction (pyruvate formate-lyase and acetate kinase) require alkaline conditions for optimum activity. A shift from homo- to heterofermentation because of increased pH has not been observed for Group N streptococci. 

Hensel, R., Mayr, R., Stetter, K. 0. and Kandler, O. 1977. Comparative studies of lactic acid dehydrogenase in lactic acid bacteria. I. Purification and kinetics of the allosteric L-lactic acid dehydrogenase from Lactobacillus casei spp. casei and, Lactobacillus curvatus. Arch. Microbiol 112, 81-93. 

Lactic acid bacteria such as Lactobacillus leichmanni and many other bacteria utilize a 5 -deoxyadenosylcobal-amin-containing enzyme to reduce nucleoside triphosphates according to Eq. 16-21. Thioredoxin or dihydrolipoic acid can serve as the hydrogen donor. Early experiments showed that protons from water are reversibly incorporated at C-2 of the reduced... 

Some lactic acid bacteria of the genus Lactobacillus, as well as Leuconostoc mesenteroides and Zymomonas mobilis, carry out the heterolactic fermentation (Eq. 17-33) which is based on the reactions of the pentose phosphate pathway. These organisms lack aldolase, the key enzyme necessary for cleavage of fructose 1,6-bisphosphate to the triose phosphates. Glucose is converted to ribulose 5-P using the oxidative reactions of the pentose phosphate pathway. The ribulose-phosphate is cleaved by phosphoketolase (Eq. 14-23) to acetyl-phosphate and glyceraldehyde 3-phosphate, which are converted to ethanol and lactate, respectively. The overall yield is only one ATP per glucose fermented. 

Fig. 5.21. The end-products (circled) of microbial fermentations of pyruvate. Letters indicate the organisms able to perform these reactions. (/<) Lactic acid bacteria (Streptococcus, Lactobacillus) (B) Clostridium propionicum (C) Yeast, Zymomonas mobilis, Sarcina ventriculr, (D) Enterobacteriaceae (Coli-aerogenes) (E) Clostridia, ...

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