Els lactobacils (Lactobacillus) són un gènere de bacteris grampositius de la família de les lactobacil·làcies (Lactobacillaceae). Són el grup característics dels bacteris làctics.
Són cocs o bacils catalasa negatius, normalment immòbils i ocasionalment tenen la capacitat de reduir el nitrat; no formen endòspores. Són neutròfils, és a dir, el seu interval de pH òptim de creixement és entre 5-8. Poden créixer entre 2 i 53 °C, però l'interval òptim de temperatura està comprès entre 30 i 40 °C. Són ubics, és a dir, es poden trobar en qualsevol ambient com ara el tracte gastrointestinal (cavitat bucal, estómac i intestí), l'aparell genitourinari masculí, la microbiota vaginal, vegetals, productes carnis, productes lactis. Poden tenir un metabolisme homofermentatiu o heterofermentatiu tant estricte com facultatiu.
Industrialment són utilitzats com a cultius iniciadors per a la producció de diversos tipus de productes fermentats com ara el iogurt i com a probiòtics en aliments i suplements alimentaris.
Taxonomia Fins al març del 2020, el gènere Lactobacillus comprenia 262 espècies, però després de la seqüenciació completa del genoma de totes elles, un grup de científics de diversos països, treballant coordinadament, van proposar la reclassificació del gènere Lactobacillus i s'han establert 23 nous gèneres: Lactobacillus, Amylolactobacillus, Holzapfelia, Bombilactobacillus, Companilactobacillus, Lapidilactobacillus, Agrilactobacillus, Schleiferilactobacillus, Lacticaseibacillus, Latilactobacillus, Loigolactobacillus, Dellaglioa, Liquorilactobacillus, Ligilactobacillus, Lactiplantibacillus, Furfurilactobacillus, Paucilactobacillus, Limosilactobacillus, Secundilactobacillus, Levilactobacillus, Fructilactobacillus, Acetilactobacillus, Apilactobacillus i Lentilactobacillus.
Comparació entre la nomenclatura del gènere Lactobacillus establerta fins al 2020 i la nova proposta feta per Zheng et al. 2020: 1901-2020Zheng et al. 2020
CaracterístiquesLactobacillaceaeLactobacillaceaeHomofermentatiusLactobacillus Lactobacillus Lactobacillus delbrueckii
(Beijerinck 1901)Lactobacillus delbrueckiiBacils grampositius, termòfils, homofermentatius i no formadors d'espores.
Poden fermentar gran diversitat de glúcids i tenen soques amb l'habilitat de fermentar fructans extracel·lulars, midó, glicogen o mannitol.
S'adapten a l'hoste.
P. ex. Lactobacillus melliventris està adaptat a les abelles.
Gènere destacat de la microbiota intestinal i de la vaginal.
Presents en la fermentació de productes lactis i de cereals.
Utilitzats com a cultius iniciadors per a la fabricació de productes lactis fermentats.Lactobacillus acetotolerans
(Etani et al. 1986)Lactobacillus acetotolerans Lactobacillus acidophilus
(Handsen and Mocquot 1970)Lactobacillus acidophilus Lactobacillus amylolyticus
(Bohak et al. 1999)Lactobacillus amylolyticusLactobacillus amylovorus
(Nakamura 1981)Lactobacillus amylovorusLactobacillus apis
(Killer et al. 2014)Lactobacillus apisLactobacillus bombicola
(Praet et al. 2015)Lactobacillus bombicola Lactobacillus colini
(Zhang et al. 2017)Lactobacillus coliniLactobacillus crispatus
(Moore and Holdeman 1970)Lactobacillus crispatusLactobacillus equicursoris
(Morita et al. 2010)Lactobacillus equicursoris Lactobacillus fornicalis
(Dicks et al. 2000)Lactobacillus fornicalisLactobacillus gallinarum
(Fujisawa et al. 1992)Lactobacillus gallinarumLactobacillus gasseri
(Lauer and Kandler 1980)Lactobacillus gasseriLactobacillus gigeriorum
(Cousin et al. 2012)Lactobacillus gigeriorum Lactobacillus hamsteriLactobacillus hamsteriLactobacillus helsingborgensis
(Olofsson et al. 2014)Lactobacillus helsingborgensisLactobacillus helveticus
(Bergey et al. 1925)Lactobacillus helveticusLactobacillus hominis
(Cousin et al. 2013)Lactobacillus hominisLactobacillus iners
(Falsen et al. 1999)Lactobacillus inersLactobacillus intestinalis
(Fujisawa et al. 1990)Lactobacillus intestinalisLactobacillus jensenii
(Gasser et al. 1970)Lactobacillus jenseniiLactobacillus johnsonii
(Fujisawa et al. 1992)Lactobacillus johnsoniiLactobacillus kalixensis
(Roos et al. 2005)Lactobacillus kalixensisLactobacillus kefiranofaciens
(Fujisawa et al. 1988)Lactobacillus kefiranofaciensLactobacillus kimbladii
(Olofsson et al. 2014)Lactobacillus kimbladiiLactobacillus kitasatonis
(Mukai et al. 2003)Lactobacillus kitasatonisLactobacillus kullabergensis
(Olofsson et al. 2014)Lactobacillus kullabergensisLactobacillus melliventris
(Olofsson et al. 2014)Lactobacillus melliventrisLactobacillus mulieris
(Rocha et al. 2020)Lactobacillus mulierisLactobacillus panisapium
(Wang et al. 2018)Lactobacillus panisapiumLactobacillus paragasseri
(Tanizawa et al. 2018)Lactobacillus paragasseriLactobacillus pasteurii
(Cousin et al. 2013)Lactobacillus pasteuriiLactobacillus porci
(Kim et al. 2018)Lactobacillus porciLactobacillus psittaci
(Lawson et al. 2001)Lactobacillus psittaciLactobacillus rodentium
(Killer et al. 2014)Lactobacillus rodentiumLactobacillus taiwanensis
(Wang et al. 2009)Lactobacillus taiwanensisLactobacillus ultunensis
(Roos et al. 2005)Lactobacillus ultunensisLactobacillus xujianguonis
(Meng et al. 2020)Lactobacillus xujianguonis Amylolactobacillus Lactobacillus amylophilus (Nakamura and Crowell 1981) Amylolactobacillus amylophilusBacils grampositius immòbils, catalasa negatius, oxidasa negatius i no formadors d'espores. Homofermentatius i tenen activitat enzimàtica amilolítica extracel·lular.Lactobacillus amylotrophicus (Naser et al. 2006)Amylolactobacillus amylotrophicus Holzapfelia Lactobacillus floricola (Kawasaki et al. 2011)Holzapfelia floricolaBacils grampositius, catalasa negatius, homofermentatius i aerotolerants. Fermenten únicament la glucosa i la fructosa. Bombilatobacillus Lactobacillus mellifer (Olofsson et al. 2014)Bombilactobacillus melliferBacils grampositius, homofermentatius i termòfils.
El B. mellifer fermenta algunes hexoses, sacarosa i rafinosa.
El B. bombi fermenta una gran diversitat de glúcids.Lactobacillus bombi
(Killer et al. 2014)Bombilactobacillus bombiLactobacillus mellis (Olofsson et al. 2014)Bombilactobacillus mellis Companilactobacillus Lactobacillus alimentarius (Reuter 1983)Companilactobacillus alimentariusBacils grampositius, homofermentatius, no formadors d'espores. Creixen entre els 25-30 °C, algunes soques poden créixer a 45 °C i algunes a 15 °C.Lactobacillus allii
(Jung et al. 2017)Companilactobacillus allii Lactobacillus baiquanensis (Wei and Gu 2019)Companilactobacillus baiquanensisLactobacillus bobalius
(Mañes‐Lázaro et al. 2008)Companilactobacillus bobalius Lactobacillus crustorum (Scheirlinck et al. 2007)Companilactobacillus crustorumLactobacillus farciminis (Reuter 1983)Companilactobacillus farciminisLactobacillus formosensis (Chang et al. 2015)Companilactobacillus formosensisLactobacillus furfuricola (Irisawa et al. 2014)Companilactobacillus furfuricolaLactobacillus futsaii
(Chao et al. 2012)Companilactobacillus futsaii Lactobacillus ginsenosidimutans
(Jung et al. 2013)Companilactobacillus ginsenosidimutans Lactobacillus halodurans (Schuster et al. 2019) Companilactobacillus haloduransLactobacillus heilongjiangensis (Gu et al. 2013)Companilactobacillus heilongjiangensis Lactobacillus huachuanensis (Fu and Gu 2019)Companilactobacillus huachuanensisLactobacillus hulinensis (Wei and Gu)Companilactobacillus hulinensisLactobacillus insicii (Ehrmann et al. 2016)Companilactobacillus insicii Lactobacillus jidongensis (Wei and Gu 2019)Companilactobacillus jidongensisLactobacillus kedongensis
(Wei and Gu 2019)Companilactobacillus kedongensisLactobacillus keshanensis
(Wei and Gu 2019)Companilactobacillus keshanensisLactobacillus kimchiensis
(Kim et al. 2013)Companilactobacillus kimchiensisLactobacillus kimchii
(Yoon et al. 2000)Companilactobacillus kimchii Lactobacillus metriopterae
(Chiba et al. 2018)Companilactobacillus metriopteraeLactobacillus mindensis
(Ehrmann et al. 2003)Companilactobacillus mindensisLactobacillus mishanensis
(Wei and Gu 2019)Companilactobacillus mishanensisLactobacillus musae
(Chen et al. 2017)Companilactobacillus musae Lactobacillus nantensis
(Valcheva et al. 2006)Companilactobacillus nantensisLactobacillus nodensis
(Kashiwagi et al. 2009)Companilactobacillus nodensis Lactobacillus nuruki
(Heo et al. 2018)Companilactobacillus nuruki Lactobacillus paralimentarius
(Cai et al. 1999)Companilactobacillus paralimentarius Lactobacillus salsicarnum
(Schuster et al. 2019)Companilactobacillus salsicarnumLactobacillus suantsaicola
(Lin et al. 2019)Companilactobacillus suantsaicolaLactobacillus tucceti
(Chenoll et al. 2009)Companilactobacillus tuccetiLactobacillus versmoldensis
(Kröckel et al. 2003)Companilactobacillus versmoldensisLactobacillus zhachilii
(Zhang et al. 2019)Companilactobacillus zhachilii Lactobacillus zhongbaensis (Wei and Gu 2019)Companilactobacillus zhongbaensis Lapidilactobacillus Lactobacillus concavus
(Tong and Dong 2005)Lapidilactobacillus concavus Bacils o cocs grampositius immòbils, homofermentatius, no formadors d'espores, catalasa negatius i anaerobis facultatius. L'interval de pH òptim de creixement i per fer ús de la pentosa depèn de la soca, normalment entre 6 i 7. L'interval de temperatura òptim de creixement és entre els 30 i els 37 °C. El producte principal de la fermentació és l'àcid L-làctic.Lactobacillus bayanensis
(Wei and Gu 2019)Lapidilactobacillus bayanensis Lactobacillus dextrinicus
(Haakensen et al. 2009)Lapidilactobacillus dextrinicus Agrilactobacillus Lactobacillus composti
(Endo and Okada 2007)Agrilactobacillus compostiBacils grampositius, catalasa negatius, homofermentatius i aerotolerants.Lactobacillus yilanensis
(Wei and Gu 2019)Agrilactobacillus yilanensis Schleiferilactobacillus Lactobacillus perolens
(Back et al. 2000)Schleiferilactobacillus perolensBacils grampositius, catalasa negatius, homofermentatius i aerotolerants.
Creixen entre 15 i 42 °C. Fermenten una gran diversitat de glúcids com les pentoses, hexoses i oligosacàrids.Lactobacillus harbinensis
(Miyamoto et al. 2006)Schleiferilactobacillus harbinensisLactobacillus shenzhenensis
(Zou et al. 2013)Schleiferilactobacillus shenzhenensis Lacticaseibacillus Lactobacillus casei
(Hansen and Lessel 1971)Lacticaseibacillus caseiBacils grampositius immòbils, oxidasa negatius, i homofermentatius.
Creixen entre 10 i 45 °C.
Normalment produeixen àcid D- i L-làctic a partir de la glucosa. Són considerades de gran importància econòmica, ja que moltes espècies són utilitzades com a cultius iniciadors i com a probiòtics.Lactobacillus baoqingensis
(Long and Gu 2019)Lacticaseibacillus baoqingensisLactobacillus brantae
(Volokhov et al. 2012)Lacticaseibacillus brantaeLactobacillus camelliae
(Tanasupawat et al. 2007)Lacticaseibacillus camelliaeLactobacillus chiayiensis
(Huang et al. 2018)Lacticaseibacillus chiayiensis Lactobacillus hulanensis
(Zhao and Gu et al. 2019)Lacticaseibacillus hulanensis Lactobacillus jixianensis
(Long and Gu, 2019)Lacticaseibacillus jixianensis Lactobacillus manihotivorans
(Morlon‐Guyot et al. 1998)Lacticaseibacillus manihotivorans Lactobacillus nasuensis
(Cai et al. 2012)Lacticaseibacillus nasuensis Lactobacillus pantheris
(Liu and Dong 2002)Lacticaseibacillus pantherisLactobacillus paracasei (Collins et al. 1989)Lacticaseibacillus paracasei Lactobacillus porcinae (Nguyen et al. 2013)Lacticaseibacillus porcinae Lactobacillus rhamnosus
(Collins et al. 1989)Lacticaseibacillus rhamnosus Lactobacillus saniviri
(Oki et al. 2012)Lacticaseibacillus saniviri Lactobacillus sharpeae
(Weiss et al. 1981)Lacticaseibacillus sharpeae Lactobacillus songhuajiangensis
(Gu et al. 2013)Lacticaseibacillus songhuajiangensis Lactobacillus thailandensis
(Tanasupawat et al. 2007)Lacticaseibacillus thailandensis Latilactobacillus Lactobacillus sakei
(Klein et al. 1996)Latilactobacillus sakei Bacils grampositius, homofermentatius.