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1.
Toxins (Basel) ; 15(1)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36668890

RESUMO

Food and feed contamination by fungi, especially by toxigenic ones, is a global concern because it can pose serious health problems when the production of mycotoxins is involved. Lactic acid bacteria (LAB), well-known for fermenting foods, have been gaining attention for their antifungal and anti-mycotoxin properties. This work tested 14 LAB strains isolated from naturally fermented Brazilian table olives for growth inhibition of Aspergillus flavus, Aspergillus carbonarius, Penicillium nordicum, and Penicillium expansum. The strains Lacticaseibacillus paracasei subsp. paracasei CCMA 1764, Levilactobacillus brevis CCMA 1762, and Lactiplantibacillus pentosus CCMA 1768 showed the strongest antifungal activity, being more active against P. expansum. Aflatoxin B1 (AFB1), ochratoxin A (OTA), and patulin (PAT) production was reduced essentially by mycelia growth inhibition. The main organic acids detected in the cell free supernatant (CFS) were lactic and acetic acids. Tested LAB exhibited adsorption capacity against AFB1 (48-51%), OTA (28-33%), and PAT (23-24%). AFB1 was converted into aflatoxin B2a (AFB2a) by lactic and acetic acids produced by the strain CCMA 1764. A similar conversion was observed in solutions of these organic acids (0.1 M). These findings demonstrate the potential of isolated LAB strains as natural agents to control toxigenic fungi and their mycotoxins in fermented products, such as table olives.


Assuntos
Lactobacillales , Olea , Patulina , Antifúngicos/farmacologia , Olea/microbiologia , Brasil , Fungos , Aflatoxina B1
2.
Toxins (Basel) ; 15(1)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36668894

RESUMO

The aim of this study was to select a lactic acid bacteria (LAB) strain for bio-conversion of Spirulina, a cyanobacteria ("blue-green algae"), into an ingredient with a high concentration of gamma-aminobutyric acid (GABA) for human and animal nutrition. For this purpose, ten different LAB strains and two different fermentation conditions (SMF (submerged) and SSF (solid state fermentation)) were tested. In addition, the concentrations of fatty acids (FA) and biogenic amines (BA) in Spirulina samples were evaluated. It was established that Spirulina is a suitable substrate for fermentation, and the lowest pH value (4.10) was obtained in the 48 h SSF with Levilactobacillus brevis. The main FA in Spirulina were methyl palmitate, methyl linoleate and gamma-linolenic acid methyl ester. Fermentation conditions were a key factor toward glutamic acid concentration in Spirulina, and the highest concentration of GABA (2395.9 mg/kg) was found in 48 h SSF with Lacticaseibacillus paracasei samples. However, a significant correlation was found between BA and GABA concentrations, and the main BA in fermented Spirulina samples were putrescine and spermidine. Finally, the samples in which the highest GABA concentrations were found also displayed the highest content of BA. For this reason, not only the concentration of functional compounds in the end-product must be controlled, but also non-desirable substances, because both of these compounds are produced through similar metabolic pathways of the decarboxylation of amino acids.


Assuntos
Lactobacillales , Spirulina , Animais , Humanos , Fermentação , Aminoácidos/metabolismo , Ácido gama-Aminobutírico/metabolismo , Lactobacillales/metabolismo , Aminas Biogênicas
3.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688755

RESUMO

This study aimed to investigate the possible production of bacteriocin-like inhibitory substances (BLIS) and optimize it by Lactobacillus sakei and combined Lactobacillus curvatus/Pediococcus acidilactici, lactic acid bacteria used for the meat fermentation. The effect of growth parameters on BLIS production was evaluated by measuring the antibacterial activity of the cell-free supernatant of these bacteria. The stability of the cell-free supernatant of combined L.curvatus/P.acidilactici bacteria was also examined after heat treatment and pH variations. Results showed highest BLIS production by L.curvatus/P.acidilactici was at growth temperatures of 28°C and pH 5, while the optimum condition for production of BLIS by L.sakei was 24°C and pH 6.5. The BLIS production by L. curvatus/P. acidilactici bacteria was greatly influenced by carbon and nitrogen sources. The antimicrobial activity of BLIS in supplemented De Man, Rosa, and Sharpe broth (MRS) was 2044.44 AU/mL, 4.84-fold greater than unsupplemented MRS. None of the carbon sources used in this study affected the BLIS production by the L.sakei, while pea peptone enhanced the antimicrobial activity and showed a value of 188.89 AU/mL, 1.47-fold greater than unsupplemented MRS. The characterization of the cell-free supernatant of L. curvatus/P. acidilactici bacteria showed the heat stability and activity of BLIS at pH 2-10.


Assuntos
Bacteriocinas , Lactobacillales , Antibacterianos/farmacologia , Bactérias , Carbono , Lactobacillus
4.
PLoS One ; 18(1): e0280412, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36656809

RESUMO

BACKGROUND: Excessive and irrational use of antibiotics as growth promoters in poultry has been one of key factors contributing to increased emergence of antibiotics resistant bacteria. Several alternatives for antibiotic growth promoters are being sought, and the search for effective probiotics to be used as feed additives is amongst the promising ones. Our study aimed to isolate and test potential probiotics bacteria from cloacal swabs of various indigenous chicken (Gallus domesticus) breeds from rural outskirts of the Kathmandu valley (Nepal). METHODS: Selective isolation of probiotics was conducted by micro-aerophilic enrichment of sample in MRS Broth at 37°C, followed by culturing on MRS agar supplemented with 5 g/L of CaCO3. Isolated bacterial colonies producing transparent halo were selected as potential lactic acid bacteria (LAB), and tested for their antibacterial activity, phenotypic and biochemical characteristics, acidic yield, and tolerance to acid and bile. RESULTS: A total of 90 potential LAB were isolated from cloacal samples collected from 41 free-ranging chickens of indigenous breeds. Of these, 52 LAB isolates (57%) showed variable antibacterial activity to at least one bacterial pathogen. Of 52 LAB, 46 isolates fulfilled phenotypic and biochemical criteria of Lactobacillus spp. Of these, 37 isolates produced varying percentage yields of lactic acid, 27 isolates showed survival at pH 3.0, and 17 isolates showed survival tolerances in the presence of 0.3% and 0.5% bile salts for 24 hours. Phylogenetic analysis of 16S rDNA sequencing of LAB isolates fulfilling in vitro probiotics properties showed that 3 isolates had genetic identity of 99.38% with Lactobacillus plantarum, while one isolate was genetically similar (99.85%) with the clade of L. reuteri, L. antri and L. panis. CONCLUSION: Our study identified four Lactobacillus spp. strains having potential probiotics properties. Further investigations are needed to evaluate these isolates to be used as poultry probiotics feed supplement.


Assuntos
Lactobacillales , Probióticos , Animais , Galinhas/microbiologia , Filogenia , Nepal , Lactobacillus , Antibacterianos/farmacologia , Aves Domésticas/genética , Ácidos/farmacologia , Probióticos/farmacologia , RNA Ribossômico 16S/genética
5.
Sci Rep ; 13(1): 440, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36624130

RESUMO

A total of 50 lactic acid bacteria (LAB) isolates from Iranian traditional dairy products (Motal and Lighvan cheeses, and artisanal yogurt) were screened for gamma-aminobutyric acid (GABA) production. Firstly, a rapid colorimetric test was performed to evaluate the glutamate decarboxylase (GAD) activity among the LAB isolates examined. Thin layer chromatography (TLC) was then performed on selected strains to identify isolates with high/moderate GABA producing capacity, and a GABase micro-titer plate assay was employed to quantify GABA. Finally, two Lactococcus (Lac.) lactis strains were selected for GABA production optimization via Response Surface Methodology (RSM) following Central Composite Design (CCD). Forty-one out of the 50 isolates showed GAD activity according to the colorimetric assay. Eight isolates displayed strong GAD activity, while nine showed no activity; low to moderate GAD activity was scored for all other isolates. GABA production was confirmed by TLC in all isolates with high GAD activity and in four selected among isoaltes with moderate activity. Among the Lactococcus strains tested, Lac. lactis 311 and Lac. lactis 491 were the strongest GABA producers with amounts of 3.3 and 1.26 mM, respectively. These two strains were subjected to GABA production optimization applying RSM and CCD on three key variables: Monosodium glutamate concentration (MSG) (between 25 and 150 mM), incubation temperature (between 25 and 37 °C), and pH (between 4.0 and 5.0). Optimal conditions for GABA production by Lac. lactis 311 and Lac. lactis 491 of temperature, pH and MSG concentration were, respectively, 35.4 and 30 °C, pH 4.5 and 4.6, and MSG concentration of 89 and 147.4 mM, respectively. Under the above conditions, the amount of GABA produced by Lac. lactis 311 and Lac. lactis 491 was 0.395 and 0.179 mg/mL, respectively. These strains and the optimal culture conditions determined in this study could be used for the biotechnological production of GABA or applied in food fermentations for the development of naturally GABA-enriched foods.


Assuntos
Lactobacillales , Irã (Geográfico) , Glutamato de Sódio , Ácido gama-Aminobutírico , Laticínios
6.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688744

RESUMO

This study aimed to isolate LAB strains with antimicrobial activity that can be used as bio-protective agents, from yogurt, pickle, and cheese samples, which are Turkish traditional fermented foods, and to reveal the potential probiotic properties of these isolates with antimicrobial activity. In addition, it was aimed for the first time to examine the potential and uniqueness of these domestic and local traditional fermented foods. In the study, a total of 682 LAB isolates from Turkish traditional fermented samples were isolated. Thirteen isolates with both high and antifungal activities were selected; four Lactiplantibacillus pentosus strains, six Lactiplantibacillus plantarum strains, and one each Enterococcus lactis, Enterococcus durans, and Enterococcus faecalis strains. Ten isolates of them were suggested as potential probiotics (excluding 1Y2-1, 1Y7-3, and 3Y12-4). It was thought that the L. pentosus 2Y7-1, which was slow to produce acid, could be used as a co-culture in fermented products with a long ripening stage, supported by enriching the product of its milk coagulation, ß-galactosidase, proteolytic, and cholesterol assimilation abilities in terms of bioactive peptide and prebiotics. Another strain, E. faecalis 3Y4-3, which was high proteolytic activity, was suggested as a co-culture in fermented products to improve both organoleptic properties and increase bioactive peptides. On the other hand, among non-probiotics, L. plantarum 3Y12-4 can be used as a starter culture in fermented milk products in order to evaluate its milk coagulation, cholesterol assimilation, and proteolytic abilities. As a result, these three strains can be used in many areas, such as fermented and/or functional food production and enzyme production. In addition, this has been the first study to examine the potential and uniqueness of Turkish domestic and local traditional fermented foods in Samsun, Turkey, together, in terms of both antimicrobial and probiotic LAB isolate (multifunctional) potential and diversity.


Assuntos
Produtos Fermentados do Leite , Alimentos Fermentados , Lactobacillales , Turquia , Alimentos Fermentados/microbiologia , Colesterol , Ácido Láctico
7.
Lett Appl Microbiol ; 76(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688789

RESUMO

This study was conducted with a perception that fructose-rich niches may inhabit novel species of lactic acid bacteria that are gaining importance as probiotics and for the production of exopolysaccharides that have applications in food and pharmaceuticals. Recently, some Lactobacillus species have been reclassified as fructophilic lactic acid bacteria due to their preference for fructose over glucose as a carbon source. These bacteria are likely to be found in fructose rich niches such as flower nectar and insects that feed on it. We explored the butterfly gut and acquired a new isolate, designated as F1, of fructophilic lactic acid bacteria, which produces a glucan-type exopolysaccharide. Whole genome sequencing and in silico analysis revealed that F1 has significantly lower average nucleotide identity and DNA-DNA hybridization values as compared to its closest Apilactobacillus neighbors in phylogenetic analysis. Therefore, we declare the isolate F1 as a novel Apilactobacillus species with the proposed name of Apilactobacillus iqraium F1. Genome mining further revealed that F1 harbors genes for exopolysaccharide synthesis and health-promoting attributes. To this end, F1 is the only Apilactobacillus species harboring three diverse α-glucan-synthesis genes that cluster with different types of dextransucrases in the dendrogram. Moreover, many nutritional marker genes, as well as genes for epithelial cell adhesion and antimicrobial synthesis, were also detected suggesting the probiotic attributes of F1. Overall analysis suggests A. iqraium sp. F1 be a potential candidate for various health beneficial and pharmaceutical applications.


Assuntos
Borboletas , Lactobacillales , Probióticos , Animais , Borboletas/genética , Borboletas/metabolismo , Filogenia , Lactobacillales/genética , Frutose/metabolismo , Probióticos/metabolismo , Glucanos/metabolismo , DNA
8.
World J Microbiol Biotechnol ; 39(3): 73, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36627394

RESUMO

Fructophilic Lactic Acid Bacteria (FLAB), Fructobacillus fructosus DPC7238 and pseudofructophilic Leuconostoc mesenteroides DPC7261 and non-FLAB Limosilactobacillus reuteri DSM20016 strains were studied for their growth and morphological evolution as a function of increased fructose concentrations (0, 25, and 50% w/v) in the media. A comparison of the genomics of these strains was carried out to relate observed changes and understand fructose-rich adaptations. The viability of FLAB strains were reduced by approx. 50% at a 50% fructose concentration, while the Limosilactobacillus reuteri strain was reduced to approx. 98%. Electron microscopy demonstrated that FLAB strain, Fructobacillus. fructosus and pseudofructophilic Leuc. mesenteroides, were intact but expanded in the presence of high fructose in the medium. Limosilactobacillus reuteri, on the other hand, ruptured as a result of excessive elongation, resulting in the formation of cell debris when the medium contained more than 25% (w/v) fructose. This was entirely and quantitatively corroborated by three-dimensional data obtained by scanning several single cells using an atomic force microscope. The damage caused the bacterial envelope to elongate lengthwise, thus increasing width size and lower height. The cell surface became comparatively smoother at 25% fructose while rougher at 50% fructose, irrespective of the strains. Although Fructobacillus fructosus was highly fructose tolerant and maintained topological integrity, it had a comparatively smaller genome than pseudofructophilic Leuc. mesenteroides. Further, COG analysis identified lower but effective numbers of genes in fructose metabolism and transport of Fructobacillus fructosus, essentially needed for adaptability in fructose-rich niches.


Assuntos
Lactobacillales , Lactobacillales/genética , Lactobacillales/metabolismo , Frutose/metabolismo , Genômica , Ácido Láctico/metabolismo
9.
Curr Microbiol ; 80(2): 65, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36602627

RESUMO

The bacterial strain AGMB10547T was isolated from cow faeces deposited by the National Institute of Animal Science in Cheonan, Republic of Korea. The strain AGMB10547T possessed the phenotypic, biochemical and chemotaxonomic characteristics of the bacteria of the family Oscillospiraceae. The isolate was obligately anaerobic, non-motile, Gram-positive and rod-shaped bacteria. The growth of strain AGMB10547T occurred within 35-40 °C (optimum at 37 °C), at pH 6-7 (optimum of 7) and in the presence of 0.5-2.0% (w/v) NaCl. Based on 16S rRNA gene sequence similarity, strain AGMB10547T belonged to the genus Caproiciproducens and was most closely related to Caproiciproducens galactitolivorans BS-1T (96.9%). The DNA G+C content was 49.0 mol%. The major cellular fatty acids (> 10%) of the isolate were C14:0, C14:0 DMA, C16:1 ω9c and C16:0. The average nucleotide identity (ANI) and digital DNA-DNA Hybridization (dDDH) values between strain AGMB10547T and C. galactitolivorans BS-1T were 75.5% and 19.2%. Based on the phenotypic, genotypic, biochemical and chemotaxonomic analyses, strain AGMB10547T represents a novel species of the genus Caproiciproducens, for which the name Caproiciproducens faecalis sp. nov. is proposed. The type strain AGMB10547T (=KCTC 25200T=NBRC 115006T=GDMCC 1.2575T).


Assuntos
Ácidos Graxos , Lactobacillales , Animais , Bovinos , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Ácidos Graxos/química , Lactobacillales/genética , Hibridização de Ácido Nucleico , Fezes/microbiologia , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Fosfolipídeos/química
10.
Food Res Int ; 163: 112224, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36596153

RESUMO

In this study, genomics and metabolomics were combined to reveal possible bio-synthetic pathways of core flavor compounds in pickled chayote via lactic acid bacteria (LAB) fermentation. The Lactiplantibacillus plantarum, Levilactobacillus brevis, and Lacticaseibacillus paracasei were selected as core LAB strains with better flavor-producing ability for chayote fermentation. The genomic results showed L. plantarum contained the largest number of metabolism annotated genes, while L. brevis had the fewest. Besides, the largest number of volatile compounds was detected in chayote fermented by L. plantarum, followed by L. brevis and L. paracasei. Some unique odor-active compounds (aldehydes, esters, and alcohols) and taste-active compounds (amino acids and dipeptides) were produced by different LAB strains. Accordingly, phenylalanine metabolic pathway (M00360), amino acid metabolic decomposition pathway (the Ehrlich pathway) and the anabolic pathway (the Harris pathway), and fatty acid biosynthesis pathway (M00061) were the main biosynthesis pathway involved in the flavor formation via LAB fermentation.


Assuntos
Lactobacillales , Lactobacillus plantarum , Lactobacillales/genética , Lactobacillus/metabolismo , Lactobacillus plantarum/genética , Lactobacillus plantarum/metabolismo , Álcoois/metabolismo , Aminoácidos/metabolismo , Genômica
11.
Biosci Rep ; 43(1)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36597861

RESUMO

Synthetic biology has grown exponentially in the last few years, with a variety of biological applications. One of the emerging applications of synthetic biology is to exploit the link between microorganisms, biologics, and human health. To exploit this link, it is critical to select effective synthetic biology tools for use in appropriate microorganisms that would address unmet needs in human health through the development of new game-changing applications and by complementing existing technological capabilities. Lactic acid bacteria (LAB) are considered appropriate chassis organisms that can be genetically engineered for therapeutic and industrial applications. Here, we have reviewed comprehensively various synthetic biology techniques for engineering probiotic LAB strains, such as clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 mediated genome editing, homologous recombination, and recombineering. In addition, we also discussed heterologous protein expression systems used in engineering probiotic LAB. By combining computational biology with genetic engineering, there is a lot of potential to develop next-generation synthetic LAB with capabilities to address bottlenecks in industrial scale-up and complex biologics production. Recently, we started working on Lactochassis project where we aim to develop next generation synthetic LAB for biomedical application.


Assuntos
Produtos Biológicos , Lactobacillales , Probióticos , Humanos , Lactobacillales/genética , Edição de Genes/métodos , Engenharia Genética/métodos , Probióticos/uso terapêutico
12.
Gut Microbes ; 15(1): 2161271, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36604628

RESUMO

Fermented foods demonstrate remarkable health benefits owing to probiotic bacteria or microproducts produced via bacterial fermentation. Fermented foods are produced by the fermentative action of several lactic acid bacteria, including Leuconostoc mesenteroides; however, the exact mechanism of action of these foods remains unclear. Here, we observed that prebiotics associated with L. mesenteroides-produced exopolysaccharides (EPS) demonstrate substantial host metabolic benefits. L. mesenteroides-produced EPS is an indigestible α-glucan, and intake of the purified form of EPS improved glucose metabolism and energy homeostasis through EPS-derived gut microbial short-chain fatty acids, and changed gut microbial composition. Our findings reveal an important mechanism that accounts for the effects of diet, prebiotics, and probiotics on energy homeostasis and suggests an approach for preventing lifestyle-related diseases by targeting bacterial EPS.


Assuntos
Microbioma Gastrointestinal , Lactobacillales , Leuconostoc mesenteroides , Probióticos , Prebióticos , Lactobacillales/metabolismo , Bactérias , Fermentação
13.
Environ Res ; 216(Pt 4): 114646, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36332671

RESUMO

Microbial-assisted phytoremediation provides a green approach for remediation of metal contaminated soils. However, the impacts of mono and co-applications of lactic acid bacteria (LAB) on soil biochemical properties and phytoavailability of toxic metals in contaminated mining soils have not yet been sufficiently examined. Consequently, here we studied the effects of Lactobacillus plantarum (P), Lactobacillus acidophilus (A), and Lactobacillus rhamnosus (R) applications alone and in combination on soil enzyme activities and bioavailability and uptake of Cd and Zn by mustard (Brassica juncea) in a smelter-contaminated soil under greenhouse conditions. Among the studied bacteria, P was the most tolerant to Cd-and-Zn contamination. As compared to control, R increased the fresh and dry weight of mustard plants by 53.5% and 63.2%, respectively. Co-application of P + A increased the chlorophyll content by 28.6%, as compared to control. Addition of LAB to soil increased the activity of soil urease, alkaline phosphatase and ß-D glucosidase increased by 1.86-fold (P + R), 1.80-fold (R) and 55.16% (P + R), respectively. Application of P + A + R enhanced catalase activity (19.3%) and superoxide dismutase activity (51.2%), while addition of A alone increased peroxidase activity (POD: 15.7%). Addition of P alone and together with A (P + A) enhanced Cd and Zn phytoextraction by mustard shoots up to 51.5% and 52.5%, respectively. We conclude that the single and/or co-application of LAB decreased soil pH, promoted plant growth, antioxidant and enzyme activities, and enhanced the phytoavailability of Cd and Zn in the studied contaminated soil. These findings might be an aid for enhancing the phytoremediation of Cd and Zn using LAB and mustard as a bioenergy crop, which may offer new ideas for field treatment of toxic metals contaminated soils.


Assuntos
Lactobacillales , Poluentes do Solo , Antioxidantes , Biodegradação Ambiental , Bioengenharia , Cádmio/análise , Cádmio/toxicidade , Metais Pesados/análise , Metais Pesados/toxicidade , Mostardeira , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Zinco/análise , Zinco/toxicidade
14.
Int J Biol Macromol ; 226: 111-120, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36493920

RESUMO

Exopolysaccharide (EPS) biomolecules produced by lactic acid bacteria (LAB) are of prodigious interest due to their unique structural, physico-chemical, and functional characteristics. Several genera of LAB including Enterococcus spp. have been studied for EPS production by various research groups worldwide. EPS produced by various strains from Enterococcus spp. have shown a wide range of functional and technological properties with potential commercial applications. Numerous techniques are used in the characterization of Enterococcus EPS to reveal their structure, linkage, monosaccharide units, functional groups, morphology, and thermal properties. Bioactive potentials of Enterococcus EPS include antioxidant, antibacterial, antibiofilm, anticancer, immunological, prebiotic, and antidiabetic potentials which have been widely reported. These functional and biological properties make Enterococcus EPS a candidate of great importance for multiple applications in the area of food, pharmaceuticals, biomedical and environmental. This review is focused on EPS produced by various strains of the Enterococcus genus isolated from different sources. Several procedures and parameters involved in the production and purification of Enterococcus EPS are also deliberated along with the functional aspects and potential applications.


Assuntos
Lactobacillales , Polissacarídeos Bacterianos , Polissacarídeos Bacterianos/química , Enterococcus , Prebióticos , Antioxidantes/farmacologia
15.
Food Chem ; 408: 135155, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36528989

RESUMO

Lactic acid bacteria (LAB) have exhibited strain/species specificity for different food matrices. We investigated the impact of LAB fermentation on the flavor, chemical profile, and bioactivity of goji juice. The colony counts of five selected strains reached above 8.5 log CFU/mL. The fermentation increased the organic acids, decreased the sugars, and improved the sensory quality of goji juice. The majority of the strains had increased acetic acid, heptanoic acid, ethyl phenylacetate, and linalool levels. Specific strains suppressed α-glucosidase and pancreatic lipase activities and increased the antioxidant activities of fermented goji juice. Based on non-targeted metabolomics and activities, 23 important differential metabolites were screened among 453 metabolites. The quantification results showed that isoquercitrin and m-coumaric content varied among strains, reflecting the strain specificity in flavone and flavonol biosynthesis and phenylalanine, tyrosine, and tryptophan biosynthesis. These findings will provide useful information for fermented goji juice biochemistry research.


Assuntos
Lactobacillales , Lactobacillales/metabolismo , Fermentação , Sucos de Frutas e Vegetais , Metaboloma , Alimentos
16.
Curr Microbiol ; 80(1): 19, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36460789

RESUMO

The bacterial pathogen of oily spot disease, a major threat to pomegranate growers, was isolated from infected plant parts of pomegranate collected from orchards in Maharashtra, India. The pathogen was identified as Xanthomonas axonopodis pv. punicae (Xap) following phenotypic and molecular characterization by 16S rRNA gene sequencing. It produced pectinase, cellulase, xylanase in medium and in experimentally inoculated tissues with pathogen where pectinase activity was maximum (32.2 U/g). Pearson correlation analysis showed a perfect positive correlation (P < 0.05) between enzyme activity and disease rating scale. This indicates the co-synthesis of hydrolytic enzymes that aid in tissue degradation and suggests their role as virulence factors. Out of 150 indigenously isolated lactic acid bacteria (LAB), Lactococcus lactis subsp. cremoris PB6, Lactobacillus brevis PFR77 and L. lactis subsp. cremoris PFL9, the potent antagonists of Xap, were used in the management of bacterial blight. Under laboratory conditions, cell formulation of PB6, PFR77 and PFL9 were equally effective (P > 0.05) and significantly (P < 0.05) reduced the infection in fruits. Under field conditions, the disease severity index for the treatments where plants received a spray of PB6 with streptocycline, was lowest (4.61%) as compared to cells (15.74%), culture supernatant (20.66%) and their integrated treatments (21.38%), and streptocycline (15.37%) treatments. However, no significant difference (P > 0.05) was noticed between cells and streptocycline treatments, thus, indicating the effectiveness of LAB in treating bacterial blight. This is the first report on the use of antagonistic LAB for the control of oily spot disease of pomegranate.


Assuntos
Lactobacillales , Romã (Fruta) , Lactobacillales/genética , Frutas , Poligalacturonase , RNA Ribossômico 16S/genética , Índia
17.
Food Res Int ; 162(Pt A): 111930, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461189

RESUMO

The objective of this study was to develop a highly bioactive postbiotic for weight management by bioconversion of whey (WHE) and polyphenol-rich citrus pomace extract (CPX) using kefir lactic acid bacteria (LAB). WHE and CPX bioconverted by kefir LAB (CPB) were fed to C57BL/6J mice on high-fat diets for five weeks and compared with oral administrations of saline (CON), WHE, CPX, and kefir LAB. Hesperetin, a potential therapeutic agent for obesity, was increased in the CPB after bioconversion from an inactive precursor. Compared with the CON group, the CPB group showed significantly reduced body weight gain, adipose tissue weight/body weight ratio, hypertriglyceridemia, and adipocyte diameter along with increased gene expression related to energy expenditure in adipose tissue (p < 0.05). Interestingly, the abundance of gut microbiota related to butyrate production was significantly altered in the CPB group compared with the CON group. There was a significant correlation between obesogenic biomarkers and the abundance of butyrate-producing and obesogenic gut microbiota. In conclusion, kefir LAB-derived bioconversion of WHE and CPX may be effective in combating obesity and obesity-related diseases.


Assuntos
Citrus , Kefir , Lactobacillales , Camundongos , Animais , Dieta Hiperlipídica/efeitos adversos , Soro do Leite , Disbiose , Camundongos Endogâmicos C57BL , Proteínas do Soro do Leite , Obesidade , Butiratos , Extratos Vegetais
18.
Food Res Int ; 162(Pt A): 111944, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461200

RESUMO

In sub-Saharan Africa, malnutrition occurs in various forms going from micronutrient deficiency (MND) to severe malnutrition. In this scenario, African indigenous leafy vegetables (AILVs) could help in alleviating hunger and food insecurity. Principally used by smallholder farmers as subsistence crops thanks to the ease of growing, AILVs have been reported to have valuable nutrient content. Nevertheless, rough handling coupled with microbial activities could lead to phyllosphere deterioration, hence leading to spoilage events that make the sustainable supply and consumption of AILVs difficult. Reviewing the literature regarding AILVs' phyllosphere microbiota, some bacteria such as Pseudomonadaceae, Enterobacteriaceae, and lactic acid bacteria (LAB) were commonly found. Their ability to deteriorate vegetables is known, thus stressing the necessity to valorize these commodities. In this review, fermentation was deepened as an inexpensive form of food processing to valorize AILVs, modulating the phyllosphere microbiota in favor of fermenting microorganisms. The literature review revealed that traditional methods implying alkaline fermentation lower the levels of toxigenic compounds in AILVs such as cyanhydric acid. Methods involving lactic acid bacteria (LAB) fermentation with beneficial LAB were able to control the fermentation, hindering the proliferation of spoilage (i.e. Pseudomonadaceae) and potentially pathogenic bacteria (i.e. Enterobacteriaceae). Aside, the improvement of nutritional content is achieved, obtaining increased levels of B-group vitamins, carotenoids, and the reduction of antinutrient and toxic compounds for certain AILVs. Furthermore, the AILVs' shelf life is also prolonged, thus further confirming that the final products are valorized by the fermentation processes. Howbeit, this review also points out some weaknesses in the methods. Indeed, alkaline fermentation can allow the growth of toxin-producing Bacillus spp. that can jeopardize the consumers' health. While the unpredictability of spontaneous LAB fermentation caused in some cases the resilience of certain pathogens such as Enterobacteriaceae. More studies involving alternative ways to inoculate LAB starters such as back slopping might be useful to perfect the fermentation methods and finally valorize AILVs.


Assuntos
Lactobacillales , Microbiota , Verduras , Folhas de Planta , Fermentação , Enterobacteriaceae
19.
Food Res Int ; 162(Pt A): 112007, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461302

RESUMO

Salame Piemonte is a dry-fermented meat product typical of the Piedmont region in Italy, manufactured using commercial starter cultures. This study aimed to select autochthonous starter cultures (ASCs) that could be used for sausage fermentation in order to strengthen the link with the geographical area of production and improve the sensory properties of the final product. A culture-dependent approach was adopted during three different spontaneous sausage fermentation processes to isolate and characterise the main bacterial resources involved. Dominant lactic acid bacteria (LAB) in each batch were Pediococcus pentosaceus, Latilactobacillus sakei, and Latilactobacillus curvatus; Staphylococcus xylosus was the most dominant coagulase-negative staphylococci (CNS) in all the studied batches. LAB and presumptive CNS isolates were further evaluated for their physiological properties and biotechnological potential. Thereafter, 11 strains were selected and evaluated for safety. Five selected strains (two P. pentosaceus, two L. sakei, and one S. xylosus strain) were used for pilot-scale Salame Piemonte production with seven different strain combinations. Based on the liking test, three ASC combinations led to the highest liking score compared to industrial products. These three ASCs were then used for the second pilot-scale sausage production confirming the high liking score. In summary, the use of P. pentosaceus and S. xylosus ASC significantly improved product sensory properties compared with that obtained using commercial starter cultures.


Assuntos
Lactobacillales , Produtos da Carne , Pediococcus pentosaceus , Biotecnologia
20.
Food Res Int ; 162(Pt A): 112023, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36461307

RESUMO

Lactic Acid Bacteria (LAB) could provide a valid alternative to S. cerevisiae as a starter culture for bakery products, avoiding yeast-related health problems while contributing to the technological and functional properties of bread. In this work, we evaluate the role of certain LABs (Leuconostoc citreum SB6, Weissella cibaria UC4051, Weissella confusa UC4051, and the commercial starter cultures Weissella cibaria, and Leuconostoc mesenteroides) in producing functional compounds (pro-technological, health-promoting, and postbiotic-like molecules). For this purpose, we analysed the genotypic and phenotypic features of strains, and we investigated dough fermentation from microbiological and metabolomics approaches. Results evidenced a clear discrimination between the metabolic activity of baker's yeast and LAB. The most discriminant metabolites derived from proteolysis and lipolysis, such as peptides, amino acids, and fatty acyls. Furthermore, we elucidated the different metabolism of these strains by building gene-metabolite interaction networks that pairwise compared the LAB strains of the same genus. While most of the networks showed a characteristic nucleotide metabolism, only the commercial W. cibaria exhibited an interaction network composed of amino acids and their related genes. In conclusion, our findings reveal that LAB strains under investigation, and particularly the commercial W. cibaria, can enhance the functional properties of bread.


Assuntos
Lactobacillales , Weissella , Weissella/genética , Saccharomyces cerevisiae , Pão , Leuconostoc/genética , Lactobacillales/genética , Aminoácidos
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