Identification of Lactic Acid Bacteria in Fruit Pulp Processing Byproducts and Potential Probiotic Properties of Selected Lactobacillus Strains.
This study aimed to identify lactic acid bacteria (LAB) in byproducts of fruit (Malpighia glabra L., Mangifera indica L., Annona muricata L., and Fragaria vesca L.) pulp processing. Fifty strains of LAB were identified using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequence (16S rRNA) analysis. Species belonging to Lactobacillus genus were the predominant LAB in all fruit pulp processing byproducts. The average congruency between the MALDI-TOF MS and 16S rRNA in LAB species identification reached 86%. Isolates of L. plantarum, L. brevis, L. pentosus, L. lactis and L. mesenteroides were identified with 100% congruency. MALDI-TOF MS and 16S rRNA analysis presented 86 and 100% efficiency of LAB species identification, respectively. Further, five selected Lactobacillus strains (L. brevis 59, L. pentosus 129, L. paracasei 108, L. plantarum 49, and L. fermentum 111) were evaluated for desirable probiotic-related properties and growth behavior on two different cultivation media. The exposure to pH 2.0 sharply decreased the counts of the different Lactobacillus strains after a 1 or 2 h incubation, while varied decreases were noted after 3 h of exposure to pH 3.0. Overall, the exposure to pH 5.0 and to bile salts (0.15, 0.30, and 1.00%) did not decrease the counts of the Lactobacillus strains. All tested Lactobacillus strains presented inhibitory activity against Staphylococcus aureus, Salmonella Typhimurium, Salmonella Enteritidis, Listeria monocytogenes and Escherichia coli, and presented variable susceptibility to different antibiotics. The selected Lactobacillus strains presented satisfactory and reproducible growth behavior. In conclusion, MALDI-TOF MS and 16S rRNA analysis revealed high efficiency and congruency for LAB species identification, and the selected Lactobacillus strains may be candidates for further investigation of novel probiotic strains.
Laboratório de Microbiologia de Alimentos, Departamento de Nutrição, Universidade Federal da Paraíba João Pessoa, Brazil.
Estefânia F
EF
Garcia
Laboratório de Microbiologia de Alimentos, Departamento de Nutrição, Universidade Federal da Paraíba João Pessoa, Brazil.
Winnie A
WA
Luciano
Laboratório de Microbiologia de Alimentos, Departamento de Nutrição, Universidade Federal da Paraíba João Pessoa, Brazil.
Danilo E
DE
Xavier
Laboratório de Processos Microbianos em Alimentos, Departamento de Engenharia de Alimentos, Universidade Federal da Paraíba João Pessoa, Brazil.
Whyara C A
WC
da Costa
Laboratório de Genômica e Proteômica, Universidade Católica de Brasília Brasília, Brazil.
Kleber
K
de Sousa Oliveira
Laboratório de Genômica e Proteômica, Universidade Católica de Brasília Brasília, Brazil.
Octávio L
OL
Franco
Grupo Interdepartamental de Pesquisa em Engenharia Metabólica, Departamento de Genética, Universidade Federal de Pernambuco Recife, Brazil.
Marcos A
MA
de Morais Júnior
Grupo Interdepartamental de Pesquisa em Engenharia Metabólica, Departamento de Genética, Universidade Federal de Pernambuco Recife, Brazil.
Brígida T L
BT
Lucena
Instituto de Microbiologia Paulo Góes, Universidade Federal do Rio de Janeiro Rio de Janeiro, Brazil.
Renata C
RC
Picão
Laboratório de Processos Microbianos em Alimentos, Departamento de Engenharia de Alimentos, Universidade Federal da Paraíba João Pessoa, Brazil.
Marciane
M
Magnani
VTT Technical Research Centre of Finland Espoo, Finland.
Maria
M
Saarela
Laboratório de Microbiologia de Alimentos, Departamento de Nutrição, Universidade Federal da Paraíba João Pessoa, Brazil.
Evandro L
EL
de Souza
16S rRNA gene sequencing; Lactobacillus; MALDI-TOF profiling; fruit; probiotic