30 A. Costantini et al.
There is also a third group comprised of strict homofermenters that has never
been found in wine.
Several species ofLactobacillushave been isolated from grapes and wines world-
wide, includingL. brevis,L. buchneri,L. casei,L. paracasei,L. cellobiosus,L. cur-
vatus,L. delbrueckii,L. diolivorans,L. fructivorans,L. heterohiochii,L. hilgardii,
L. jensenii, L. kunkeei,L. leichmanni,L. lindneri, L. mali,L. nagelli,L. paracasei,
L. plantarum,L. trichodes, L. vermiforme,L. vini,L. yamanashiensisandL. zeae
(Douglas and Cruess 1936; Fornachon 1957; Costello et al. 1983; Lafon-Lafourcade
et al. 1983; Davis et al. 1986; Sieiro et al. 1990; Edwards et al. 2000; Du Plessis
et al. 2004; Beneduce et al. 2004; Moreno-Arribas and Polo 2008).
2.2.1.2Pediococcus
Cells are non-mobile and have a spherical shape; these are the only LAB that sepa-
rate into two planes, which results in the formation of pairs, tetrads or large clumps
of spherical cells.
Bacteria belonging to this genera are facultative anaerobes and require a rich
medium containing growth factor and fermentable sugar for their development.
Their optimum temperature is 25–30◦C with a pH value of 6. They are homofer-
mentative, which means that all the glucose is metabolized into lactic acid and they
do not ferment pentose.
Among the approved species ofPediococcus(Garvie 1986), only four have been
isolated from wines:P. damnosus,P. parvulus,P. inopinatusandP. pentosaceus
(Davis et al. 1986; Edwards and Jensen 1992);P. pentosaceusandP. parvulusare
the most common species in this medium.
2.2.1.3Oenococcus
Oenococcus oeniis described as a Gram-positive non-mobile coccus and frequently
occurs in pairs and chains of different sizes (Fig. 2.2).
Oenococcusis a facultative acidophilic anaerobe and grows at pH 4.8 with tem-
peratures between 18◦C and 30◦C. It requires a rich medium supplemented with
tomato juice or grape juice, and its growth is not inhibited in the presence of 10%
ethanol. Glucose is fermented in lactic acid, carbon dioxide, acetic acid and ethanol
(it is a heterofermenter). It converts malate into lactate and CO 2 in the presence of
fermentable carbohydrate.
Wine bacteria belonging to the genusOenococcuswere previously classified as
Leuconostoc oenosby Garvie (1967) and were the only acidophilic members of the
genusLeuconostoc. Later, phylogenetic studies revealed thatL. oenosrepresented a
distinct subline separate from otherLeuconostocspp. (Mart ́ınez-Murcia et al. 1993),
and this bacterium was, finally, assigned to a new genus:Oenococcus(Dicks
et al. 1995).