Contribution Of Lactic Acid Bacteria Research Articles

Effect of Lactic Acid Bacteria Fermentation on Plant-Based Products

Lactic acid bacteria effectively utilize the nutrients and active compounds in plant-based materials via their powerful metabolic pathways and enzyme systems, achieving a combination of nutrition, functionality, and deliciousness. Currently, the majority of review articles predominantly concentrate on summarizing the fermentation of fruits and vegetables by lactic acid bacteria, devoting comparatively less attention to researching other plant species varieties and plant-based by-products. Furthermore, the summary of the research on the active substances and functional properties lacks sufficient depth. This review provides a comprehensive overview of the status of and technological progress in lactic acid bacteria fermentation of various plant species and plant-based by-products, and the effects of lactic acid bacteria on the active substances and functional properties are emphasized. In addition, this review emphasizes that active substances give products more functionality. The aim of this review is to emphasize the significant contribution of lactic acid bacteria to the active substances and functional properties of plant-based products, which will assist researchers in better comprehending the application value of lactic acid bacteria in the plant-based domain and direct attention towards the interaction mechanisms between active substances and product functionality. Concurrently, this review provides a certain theoretical foundation and reference for the application of fermented functional products in promoting health and preventing diseases.

Gut Microbiome Analysis and Screening of Lactic Acid Bacteria with Probiotic Potential in Anhui Swine.

With the widespread promotion of the green feeding concept of "substitution and resistance", there is a pressing need for alternative products in feed and breeding industries. Employing lactic acid bacteria represents one of the most promising antimicrobial strategies to combat infections caused by pathogenic bacteria. As such, we analyzed the intestinal tract of Anhui local pig breeds, including LiuBai Pig, YueHei Pig, and HuoShou Pig, to determine the composition and diversity of intestinal microbiota using 16S rRNA. Further, the functionality of the pigs' intestinal microbiota was studied through metagenomic sequencing. This study revealed that lactic acid bacteria were the primary contributors to the functional composition, as determined through a species functional contribution analysis. More specifically, the functional contribution of lactic acid bacteria in the HuoShou Pig group was higher than that of the LiuBai Pig and YueHei Pig. Subsequently, the intestinal contents of the HuoShou Pig group were selected for the screening of the dominant lactic acid bacteria strains. Out of eight strains of lactic acid bacteria, the acid-production capacity, growth curve, and tolerance to a simulated intestinal environment were assessed. Additional assessments included surface hydrophobicity, the self-aggregation capability, co-agglutination of lactic acid bacteria with pathogenic bacteria, and an in vitro bacteriostatic activity assay. Lactobacillus johnsonii L5 and Lactobacillus reuteri L8 were identified as having a strong overall performance. These findings serve as a theoretical basis for the further development of pig-derived probiotics, thereby promoting the application of lactic acid bacteria to livestock production.

RELEVANCE OF ETHYL LACTATE AMONG THE CACHAÇA ESTERS

ABSTRACT
 The advancement in the technology of cachaça ─ sugarcane spirit produced in the Brazilian territory ─ has led to the search for parameters that allow the improvement of its chemical characterization and sensory specificities. Esters are important aroma agents, but their routine monitoring, as endorsed in Brazilian legislation, is restricted to the quantification of ethyl acetate, which is formed through the metabolism of yeast (Saccharomyces cerevisiae). However, being produced in a rural environment using fresh cane juice, fermentation of “cachaça de alembic” involves the presence and activity of lactic acid-producing bacteria, making the presence of ethyl lactate among the cachaça esters predictable. In this work, the levels of ethyl lactate and ethyl acetate were compared in 247 samples, corresponding to 56 brands produced in eleven Brazilian states. Ethyl lactate was found in levels that significantly alter the result of the quantitative participation of esters in the composition of cachaça. This fact is especially relevant considering that lactic acid bacteria are GRAS and widely recognized as a resource for improving the sensory quality of wines and other alcoholic beverages. Thus, studies on the contribution of lactic acid bacteria to the sensory quality of cachaça should be encouraged. Ethyl lactate, in addition to signaling a chemical specificity naturally occurring in cachaça, is a marker of other possible chemical and sensory peculiarities whose research should be stimulated.

Comparative Peptidomic and Metatranscriptomic Analyses Reveal Improved Gamma-Amino Butyric Acid Production Machinery in Levilactobacillus brevis Strain NPS-QW 145 Cocultured with Streptococcus thermophilus Strain ASCC1275 during Milk Fermentation.

The high-gamma-amino butyric acid (GABA)-producing bacterium Levilactobacillus brevis strain NPS-QW 145, along with Streptococcus thermophilus (one of the two starter bacteria used to make yogurt for its proteolytic activity), enhances GABA production in milk. However, a mechanistic understanding of how Levilactobacillus brevis cooperates with S. thermophilus to stimulate GABA production has been lacking. Comparative peptidomic and metatranscriptomic analyses were carried out to unravel the casein and lactose utilization patterns during milk fermentation with the coculture. We found that particular peptides hydrolyzed by S. thermophilus ASCC1275 were transported and biodegraded with peptidase in Lb. brevis 145 to meet the growth needs of the latter. In addition, amino acid synthesis and metabolism in Lb. brevis 145 were activated to further support its growth. Glucose, as a result of lactose hydrolysis by S. thermophilus 1275, but not available lactose in milk, was metabolized as the main carbon source by Lb. brevis 145 for ATP production. In the stationary phase, under acidic conditions due to the accumulation of lactic acid produced by S. thermophilus 1275, the expression of genes involved in pyridoxal phosphate (coenzyme of glutamic acid decarboxylase) metabolism and glutamic acid decarboxylase (Gad) in Lb. brevis 145 was induced for GABA production.SIGNIFICANCE A huge market for GABA-rich milk as a dietary therapy for the management of hypertension is anticipated. The novelty of this work lies in applying peptide profiles supported by metatranscriptomics to elucidate (i) the pattern of casein hydrolysis by S. thermophilus 1275, (ii) the supply of peptides and glucose by S. thermophilus 1275 to Lb. brevis 145, (iii) the transportation of peptides in Lb. brevis and the degradation of peptides by this organism, which was reported to be nonproteolytic, and (iv) GABA production by Lb. brevis 145 under acidic conditions. Based on the widely reported contribution of lactic acid bacteria (LAB) and GABA to human health, the elucidation of interactions between the two groups of bacterial communities in the production of GABA-rich milk is important for promoting the development of functional dairy food and may provide new insight into the development of industrial GABA production.

Evaluation and characterization of some protective culture metabolites in free and nano-chitosan-loaded forms against common contaminants of Egyptian cheese

This research attempted to inspect the contribution of lactic acid bacteria (LAB) with nanoparticle application in antimicrobial enhancement. Seven lactic acid cultures-free supernatants (CFSs) in both free and nanoparticles-loaded states were examined against seven foodborne microorganisms. Lactobacillus helveticus followed by Lactobacillus Plantarum possessed considerable antimicrobial activity. Headspace GC–MS characterization of Lactobacillus helveticus CFS identified a mixture of antimicrobial and health-promoting compounds. Minimal inhibitory concentration (MIC) values for tested Gram-positive bacteria represented 50% of that for Gram-negative bacteria, 20% and 7.35% of those for fungus and yeast respectively. Nanoparticles were prepared through chitosan-tripolyphosphate nanoparticle formation giving nanospheres from in the range from 5 to 10 nm, and narrow size distribution. CFS-loaded chitosan nanoparticles (CS-NPs) significantly enhanced the overall inhibition zone diameter, as well as, the decline in MIC values for Salmonella enterica (50%) and Penicillium chrysogenum (12.5%) was observed. Lactobacillus helveticus CFS, however, displayed lower antimicrobial activity vs. nisin and natamycin, it has both antibacterial and antifungal promising activities.

Unravelling the contribution of lactic acid bacteria and acetic acid bacteria to cocoa fermentation using inoculated organisms

Cocoa beans (Theobroma cacao L.) are the raw material for chocolate production. Fermentation of the bean pulp by microorganisms is essential for developing the precursors of chocolate flavour. Currently, the cocoa fermentation is still conducted by an uncontrolled traditional process via a consortium of indigenous species of yeasts, lactic acid bacteria and acetic acid bacteria. Although the essential contribution of yeasts to the production of good quality beans and, typical chocolate character is generally agreed, the roles of lactic acid bacteria and acetic acid bacteria are less certain. The objective of this study was to investigate the contribution of LAB and AAB in cocoa bean fermentation by conducting small scale laboratory fermentations under aseptic conditions, inoculated with different groups of microorganisms previously isolated from spontaneous cocoa fermentations. The inoculation protocols were: (1) four yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii, Kluyveromyces marxianus and Saccharomyces cerevisiae; (2) four yeasts plus the lactic acid bacteria Lactobacillus plantarum and Lactobacillus fermentum; (3) four yeasts plus the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateuri and (4) four yeasts plus two lactic acid bacteria and two acetic acid bacteria. Only the inoculated species were detected in the microbiota of their respective fermentations. Beans from the inoculated fermentations showed no significant differences in colour, shell weights and concentrations of residual sugars, alcohols and esters (p>0.05), but they were slightly different in contents of lactic acid and acetic acid (p<0.05). All beans were fully brown and free of mould. Residual sugar levels were less than 2.6 mg/g while the shell contents and ethanol were in the range of 11–13.4% and 4.8–7 mg/g, respectively. Beans fermented in the presence of LAB contained higher levels of lactic acid (0.6-1.2 mg/g) whereas higher concentrations of acetic acid (1.8–2.2 mg/g) were detected in beans inoculated with AAB.Triangle and hedonic sensory evaluations of chocolates prepared from beans taken from the three fermentations showed no significant differences (p > 0.05). It was concluded that the growth of lactic acid bacteria and acetic acid bacteria may not be essential for the fermentation of cocoa beans.

The effect of lactic acid bacteria on cocoa bean fermentation

Cocoa beans (Theobroma cacao L.) are the raw material for chocolate production. Fermentation of cocoa pulp by microorganisms is crucial for developing chocolate flavor precursors. Yeasts conduct an alcoholic fermentation within the bean pulp that is essential for the production of good quality beans, giving typical chocolate characters. However, the roles of bacteria such as lactic acid bacteria and acetic acid bacteria in contributing to the quality of cocoa bean and chocolate are not fully understood. Using controlled laboratory fermentations, this study investigated the contribution of lactic acid bacteria to cocoa bean fermentation. Cocoa beans were fermented under conditions where the growth of lactic acid bacteria was restricted by the use of nisin and lysozyme. The resultant microbial ecology, chemistry and chocolate quality of beans from these fermentations were compared with those of indigenous (control) fermentations. The yeasts Hanseniaspora guilliermondii, Pichia kudriavzevii, Kluyveromyces marxianus and Saccharomyces cerevisiae, the lactic acid bacteria Lactobacillus plantarum, Lactobacillus pentosus and Lactobacillus fermentum and the acetic acid bacteria Acetobacter pasteurianus and Gluconobacter frateurii were the major species found in control fermentations. In fermentations with the presence of nisin and lysozyme, the same species of yeasts and acetic acid bacteria grew but the growth of lactic acid bacteria was prevented or restricted. These beans underwent characteristic alcoholic fermentation where the utilization of sugars and the production of ethanol, organic acids and volatile compounds in the bean pulp and nibs were similar for beans fermented in the presence of lactic acid bacteria. Lactic acid was produced during both fermentations but more so when lactic acid bacteria grew. Beans fermented in the presence or absence of lactic acid bacteria were fully fermented, had similar shell weights and gave acceptable chocolates with no differences in sensory rankings. It was concluded that lactic acid bacteria may not be necessary for successful cocoa fermentation.

Influence of diets to Wistar rats supplemented with soya, flaxseed and lupine products treated by lactofermentation to improve their gut health

The present study proposes the contribution of lactic acid bacteria and plants rich in bioactive substances and high-quality proteins as alternative products for human diets in improving the gut environment as potential against pathogenic bacteria. The effect of diets supplemented with soya, flaxseed and lupine flours fermented with a Pediococcus acidilactici KTU05-7 probiotic strain in the gastrointestinal tract (GIT) of Wistar rats were analyzed. In vivo experiments showed a positive effect of long time lactofermentation of plant material on the body weight of rats. Diets with fermented yellow lupine resulted in enhanced activities of α-glucosidase, β-galactosidases, as well as high levels of lactic acid bacteria, bifidobacteria and enterococci in the GIT were determined. Lactofermentation of analyzed plant products had a significantly lowering effect on Escherichia coli compared with the control group. The dominant flora of large intestines like Bifidobacterium and anaerobic cocci were found in high levels after diets with fermented lupine.

醸造微生物利用による製パン試験 (第3報)

The contribution of lactic acid bacteria to the quality of sour bread made with sponge doughs fermented by a brewers' yeast, Saccharomyces cerevisiae, and a homofermentative, Lactobacillus sakei, and another two lactic acid bacteria (LAB) was investigated. A remarkable increase in free amino acids, especially L-glutamic acid, was observed in the sour sponge dough fermented by L. sakei, or the dough fermented by S. cerevisiae and L. sakei. Though the same tendency was observed in those samples fermented by the last two, it was lower than that of the first. The flavor of the sour bread was believed to be derived from the moderate production of organic acids such as lactic and acetic acids, and an increase in free amino acids. Moreover, the bread with the sour sponge doughs was suggested to be more resistant to Aspergillus niger, a common spoilage fungus for bread. When rats were fed a high fat diet containing the sour bread, an increase in serum triglyceride and cholesterol levels was suppressed. The result of a binding test between the dead cells of LAB and bile acid suggested that they could bind and exclude bile acid in the small intestine of the rats.

ラットのトリプトファン加熱分解物(Trp-P1)排泄に及ぼす乳酸菌菌体投与の影響

The objective of this study was to evaluate the contribution of lactic acid bacteria on the urinary and the fecal Trp-P1 (3-amino-1, 4-dimethyl-5H-pyrido [4, 3-b] indole) excretion. Eight weeks old Wister strain male rats were housed in individual cages, in an air-conditioned room where the temperature was maintained at 22°C and Humidity at 50±5% were maintained. The rats were divided into two groups of four each. They were fed ad libitum powdered Oriental rat chow supplemented with 1% w/w or 9% w/w lyophilized Lactobacillus casei subsp. casei R-52 cells (4.1×109 cfu/g)and water. After 4 days of preliminary feeding, 1.0ml of Trp-Pl solution (2.0mg/ml) was infused into the stomach. After 24 hours of Trp-P1 infusion, samples of feces and urine were collected separately for 2 days at 24 hours intervals. Trp-P1 concentration in all the samples were analyzed using HPLC. Administration of the chow supplemented with lyophilized Lactobacillus casei subsp. casei R-52 cells showed no effect on fecal Trp-P1 excretion was observed. However, the concentration of Trp-P1 in the urine was significantly increased by the administration of the chow supplemented with 9% w/w cells (p<0.05), but not with 1% w/w.

Contribution of lactic acid bacteria to cheese ripening.

The fermentation of milk for the production of cheese has been conducted for 8,000 years; however, a well developed understanding of the compounds involved in cheese flavor development, and the mechanism of their formation, is still lacking. Additionally, any discussion of cheese flavor development is complicated by the fact that approximately 4,000 different cheese varieties, with a variety of flavor and/or texture characteristics, are produced world-wide. The ability to manufacture this wide array of products from milk is the result of manufactures using a variety of processing conditions and microorganisms. The intent of this chapter will be to focus on the metabolic properties of lactic acid bacteria which are believed to be of general importance in cheese flavor development.

Contribution of lactic acid bacteria to flavour compound formation in dairy products

Abstract Cheese flavour cannot be produced without starter bacteria. Lactic acid bacteria convert lactose to lactic acid and this together with their production of diacetyl and acetaldehyde are their main contributions to the flavour of cultured milks and fresh cheeses. In matured cheeses, the starter bacteria die out quickly and the rate at which they lyse and release their enzymes into the system has an influence on the rate at which free amino acids are formed. Rennet alone is mainly responsible for the formation of large, medium and small peptides but, without interaction with other enzymes, is capable of producing only methionine, histidine, glycine, serine and glutamic acid at quantifiable levels. Free amino acids in Cheddar cheese are mainly the result of microbial peptidase activity. These amino acids, together with the products of glycolysis, form substrates for secondary flora, the nature of which, in many cases, determines the cheese variety. They also form substrates for enzymes from the milk, e.g. the production of H 2 S appears to be dependent on milk enzymes. Methionine, which is released by rennet, is further metabolized by starter enzymes with the production of methanethiol which plays a major role in cheese flavour possibly as a potentiator for other flavours. α—Dicarbonyls, particularly methylglyoxal and diacetyl, and bacteria which can produce them, appear to play a crucial role in the formation of cheese flavour, both the desirable flavour of full-fat cheese and the meaty-brothy off-flavour of low-fat cheese. Although, theoretically, there are many compounds in cheese which could react purely chemically to form flavour compounds, these reactions are also mediated by enzymes in the cheese system and it seems unlikely that straight out chemical reactions play a major role in the production of cheese flavour. The role of the secondary flora is likely to be much more important than that of chemical reactions. Particularly in Cheddar and Emmental it has been shown that good quality cheeses have a low oxidation-reduction potential. This is more likely to be an indicator for the establishment of the anaerobic conditions required for the flavour forming reactions to proceed than an active causal agent of flavour formation. The function of glutathione is more likely to be as some sort of facilitator in enzyme reactions than as an agent for the reduction of oxidation-reduction potential. The ability of bacteria to accumulate glutathione from their media is likely to be one of the indicators of flavour generating capacity. Suitable selected strains of adjunct bacteria increase the rate and intensity of formation of Cheddar cheese flavour but unsuitable adjuncts can also cause off-flavours.

Diacetyl and Acetaldehyde Concentrations During Ripening of Kefalotyri Cheese

ABSTRACTDiacetyl and acetaldehyde were determined during ripening of Kefalotyri cheese produced using two different lactic cultures (A: Streptococcus thermophilus + Lactobacillus casei, SI cheese, B: Streptococcus thermophilus + Streptococcus diacetylactis + Streptococcus durans, S2 cheese). Diacetyl increased until the 60th day of ripening (2.49 and 1.62 ppm for S1 and S2 cheese, respectively) and until then was found in higher concentration in trials compared with control (0.91 ppm at 60 days). The possible contribution of lactic acid bacteria, pH and acidity of these cheese on diacetyl during ripening was discussed. Acetaldehyde was detected only until the 15th day of ripening (0.17, 0.20 and 0.08 ppm for control, S1 and S2 cheese, respectively).