Lactic Acid Bacteria Lactobacillus Research Articles

Transitions in bacterial communities across two fermentation-based virgin coconut oil (VCO) production processes

Despite being one of the most used methods of virgin coconut oil (VCO) production, there is no metagenomic study that details the bacterial community shifts during fermentation-based VCO production. The identification and quantification of bacteria associated with coconut milk fermentation is useful for detecting the dominant microbial genera actively involved in VCO production which remains largely undescribed. Describing the constitutive microbial genera involved in this traditional fermentation practice can be used as a preliminary basis for improving industrial practices and developing better fermentation procedures. In this study, we utilized 16S rRNA metagenomic sequencing to trace the transitions in microbial community profiles as coconut milk is fermented to release VCO in two VCO production lines. The results show that difference in the microbiome composition between the different processing steps examined in this work was mainly due to the abundance of the Leuconostoc genus in the raw materials and its decline and transition into the lactic acid bacteria groups Weissella, Enterococcus, Lactobacillus, Lactococcus, and Streptococcus during the latter stages of fermentation. A total of 17 genera with relative abundances greater than 0.01% constitute the core microbiome of the two processing lines and account for 74%–97% of the microbial abundance in all coconut-derived samples. Significant correlations were shown through an analysis of the Spearman’s rank between and within the microbial composition and pH at the genus level. The results of the present study show that the dynamics of VCO fermentation rely on the shifts in abundances of various members of the Lactobacillales order.

Gut Microbiome as a Potential Biomarker in Fish: Dietary Exposure to Petroleum Hydrocarbons and Metals, Metabolic Functions and Cytokine Expression in Juvenile Lates calcarifer

The gut microbiome of fish contains core taxa whose relative abundances are modulated in response to diet, environmental factors, and exposure to toxicogenic chemicals, influencing the health of the host fish. Recent advances in genomics and metabolomics have suggested the potential of microbiome analysis as a biomarker for exposure to toxicogenic compounds. In this 35-day laboratory study, 16S RNA sequencing and multivariate analysis were used to explore changes in the gut microbiome of juvenile Lates calcarifer exposed to dietary sub-lethal doses of three metals: vanadium (20 mg/kg), nickel (480 mg/kg), and iron (470 mg/kg), and to two oils: bunker C heavy fuel oil (HFO) (1% w/w) and Montara, a typical Australian medium crude oil (ACO) (1% w/w). Diversity of the gut microbiome was significantly reduced compared to negative controls in fish exposed to metals, but not petroleum hydrocarbons. The core taxa in the microbiome of negative control fish comprised phyla Proteobacteria (62%), Firmicutes (7%), Planctomycetes (3%), Actinobacteria (2%), Bacteroidetes (1%), and others (25%). Differences in the relative abundances of bacterial phyla of metal-exposed fish were pronounced, with the microbiome of Ni-, V-, and Fe-exposed fish dominated by Proteobacteria (81%), Firmicutes (68%), and Bacteroidetes (48%), respectively. The genus Photobacterium was enriched proportionally to the concentration of polycyclic aromatic hydrocarbons (PAHs) in oil-exposed fish. The probiotic lactic acid bacterium Lactobacillus was significantly reduced in the microbiota of fish exposed to metals. Transcription of cytokines IL-1, IL-10, and TNF-a was significantly upregulated in fish exposed to metals but unchanged in oil-exposed fish compared to negative controls. However, IL-7 was significantly downregulated in fish exposed to V, Ni, Fe, and HFOs. Fish gut microbiome exhibits distinctive changes in response to specific toxicants and shows potential for use as biomarkers of exposure to V, Ni, Fe, and to PAHs present in crude oil.

Comparison of the gut microbiome of sacbrood virus-resistant and -susceptible Apis cerana from South Korea

Honey bees are important pollinators for the conservation of the ecosystem and agricultural products and provide a variety of products important for human use, such as honey, pollen, and royal jelly. Sacbrood disease (SD) is a devastating viral disease in Apis cerana; an effective preventive measure for SD is urgently needed. In this study, the relationship between the gut microbiome of honey bees and SD was investigated by pyrosequencing. Results revealed that sacbrood virus (SBV)-resistant A. cerana strains harbour a unique acetic acid bacterium, Bombella intestini, and the lactic acid bacteria (LAB) Lactobacillus (unclassified)_uc, Bifidobacterium longum, B. catenulatum, Lactococcus lactis, and Leuconostoc mesenteroides in larvae and Hafnia alvei, B. indicum, and the LAB L. mellifer and Lactobacillus HM215046_s in adult bees. Changes in the gut microbiome due to SBV infection resulted in loss of bacteria that could affect host nutrients and inhibit honey bee pathogens, such as Gilliamella JFON_s, Gilliamella_uc, Pseudomonas putida, and L. kunkeei in A. cerana larvae and Frischella_uc, Pantoea agglomerans, Snodgrassella_uc, and B. asteroides in adult bees. These findings provide important information for the selection of probiotics for A. cerana larvae and adults to prevent pathogenic infections and keep honey bees healthy.

Some mechanisms of Lactobacillus reuteri action as a probiotic microorganism

Some morphological, physiological and biochemical characteristics of the probiotic species of lactic acid bacteria Lactobacillus reuteri are presented in the work. This species, according to literature sources, were isolated from the normal human microbiota, other members of the class Mammalia, as well as broilers and sourdough. The study of literature and Internet sources identified the importance of using different strains of L. reuteri in modern dietary supplements.Some physiological features of this microorganism in terms of positive effects on the functioning of the human gastrointestinal tract and the formation of immunity were considered. According to processed datait is concluded that there is a necessity for further practical study of L. reuteri as a potential probiotic for the pharmaceutical and food industries.

Fermentation Characteristics and Microbiota during the Ensiling of Myriophyllum aquaticum Inoculated with Lactic Acid Bacteria

Myriophyllum aquaticum (M. aquaticum) is a commonly used aquatic macrophyte for water purification and could be utilized as animal food. However, the high water content of M. aquaticum makes it difficult for long-term preservation, which leads to challenges as an ideal animal feed ingredient. The storage of Silage for long periods may be a proper method to solve the problem. In the present paper, we assess the effects of lactic acid bacteria Lactobacillus buchneri (LB), Lactobacillus plantarum (LP), or their combination on fermentation and microbial communities during the ensiling of M. aquaticum silage. The results show that the LP-treated silage displays a higher lactic acid concentration than that in the control silage. Both LB and LP increased the abundance of Lactobacillus, but decreased the abundance of Serratia and Prevotella_9 in M. aquaticum silage after 60 days of ensiling. Both LB and LP increased the diversity and richness of fungi. Therefore, the inoculation of LP improved silage fermentation during ensiling. These results show that the inoculation of lactic acid bacteria improves the fermentation quality of M. aquaticum silage, which makes it possible for the application of M. aquaticum to animal forage in the future.

Characterization of Microbial Shifts during the Production and Ripening of Raw Ewe Milk-Derived Idiazabal Cheese by High-Throughput Sequencing.

Simple SummaryIdiazabal is a traditional cheese produced from raw ewe milk in the Basque Country (Southwestern Europe). The sensory properties of raw milk cheeses have been attributed, among other factors, to microbial shifts that occur during the production and ripening processes. In this study, we used high-throughput sequencing technologies to investigate the microbiota of Latxa ewe raw milk and the dynamics during cheese production and ripening processes. The microbiota of raw milk was composed of lactic acid bacteria (LAB), environmental bacteria and non-desirable bacteria. Throughout the cheese making and ripening processes, the growth of LAB was promoted, whereas that of non-desirable and environmental bacteria was inhibited. Moreover, some genera not reported previously in raw ewe milk were detected and clear differences were observed in the bacterial composition of raw milk and cheese among producers, in relation to LAB and environmental or non-desirable bacteria, some of which could be attributed to the production of flavour related compounds.In this study, we used high-throughput sequencing technologies (sequencing of V3–V4 hypervariable regions of 16S rRNA gene) to investigate for the first time the microbiota of Latxa ewe raw milk and the bacterial shifts that occur during the production and ripening of Idiazabal cheese. Results revealed several bacterial genera not reported previously in raw ewe milk and cheese, such as Buttiauxella and Obesumbacterium. Both the cheese making and ripening processes had a significant impact on bacterial communities. Overall, the growth of lactic acid bacteria (LAB) (Lactococcus, Lactobacillus, Leuconostoc, Enterococcus, Streptococcus and Carnobacterium) was promoted, whereas that of non-desirable and environmental bacteria was inhibited (such as Pseudomonas and Clostridium). However, considerable differences were observed among producers. It is noteworthy that the starter LAB (Lactococcus) predominated up to 30 or 60 days of ripening and then, the growth of non-starter LAB (Lactobacillus, Leuconostoc, Enterococcus and Streptococcus) was promoted. Moreover, in some cases, bacteria related to the production of volatile compounds (such as Hafnia, Brevibacterium and Psychrobacter) also showed notable abundance during the first few weeks of ripening. Overall, the results of this study enhance our understanding of microbial shifts that occur during the production and ripening of a raw ewe milk-derived cheese (Idiazabal), and could indicate that the practices adopted by producers have a great impact on the microbiota and final quality of this cheese.

Use of Autochthonous Lactic Acid Bacteria as Starter Culture of Pasteurized Milk Adobera Cheese

Adobera, a genuine, brick-shaped, lightly ripened, unstretched pasta filata-like cheese from Western México, is one of the most important market-share wise but is usually made with raw milk and prepared following artisanal procedures. A pasteurized milk cheese is needed to assess its safety and guarantee standardized quality features. However, no commercial Adobera cheese culture is available, as specific lactic acid bacteria relevant for its production have not been thoroughly identified. This study is aimed at comparing the technological and quality features of Adobera cheeses made with pasteurized milk inoculated with a mixture of autochthonous lactic acid bacteria (Lactobacillus and Leuconostoc strains) to those of traditional raw milk cheeses, hypothesizing that no significant differences would be found between them. Milk pasteurization promoted water retention into the cheese matrix, impacting its texture and color profiles. Raw milk cheeses were harder, more cohesive, and less elastic than pasteurized milk cheeses. Ripening markers were significantly higher in raw milk cheeses at all sampling times, although its evolution over time showed that the starter culture could exhibit similar proteolytic activity than that of native milk microbiota under favorable ripening conditions. The principal component analysis revealed apparent overall differences between raw Adobera cheeses and those made with pasteurized cheese milk.

Probiotic Potential of Lactic Acid Bacteria on Feed Efficiency, Weight and Carcass Percentage in Ducks

The aim of the study was to determine the effect of the use of probiotic lactic acid bacteria (Lactobacillus acidophilus, Lactobacillus casei, Lactococcus lactis, and Bifidobacterium sp) on feed efficiency, carcass weight and carcass percentage in broiler ducks. Probiotics lactic acid bacteria produce bacteriocins and organic acids that inhibit the growth of pathogenic microbes in the digestive tract of poultry, so that the intestinal villi of broiler ducks are healthy. Besides that, probiotics are able to reduce cholesterol levels in meat when consumed by humans and can improve health. This study used 48 peking ducks. The probiotics of Lactic Acid Bacteria used were a concentration of 1.2 x 108 CFU/ml. In this study there were four different treatments, namely P0 (without probiotics), P1 (given 1 ml probiotics/liter drinking water), P2 (given 2 ml probiotics/liter drinking water) and P3 (given 3 ml probiotics/liter of drinking water). The results of the feed efficiency study showed that there was a significant difference (p<0.05) in the P0, P1, P2 and P3 treatments. The highest feed efficiency was at P3 (33.81%) while the lowest was P0 (30.84%). The results of the study on carcass weight indicated that the probiotics tended to be higher than those who were not given probiotics but statistically not significantly different (p>0.05). The highest carcass weight was P3 (1749.92 g) and the lowest was P0 (1709.25 g). The results of the study on the percentage of carcass weight showed a significant difference (p<0.05) in both P0, P1, P2 and P3 treatments. The highest percentage of carcass weight was at P3 (64.60%) and the lowest was P0 (60.96%). It can be concluded that the administration of probiotics lactic acid bacteria (Lactobacillus acidophilus, Lactobacillus casei, Lactococcus lactis, and Bifidobacterium sp) at a dose of 1 ml/liter of drinking water, 2 ml/liter of drinking water and 3 ml/liter of drinking water can affect feed efficiency and the percentage of duck carcasses. but has no effect on the carcass weight of broiler ducks.

Dietary carbohydrate-to-protein ratio influences growth performance, hepatic health and dynamic of gut microbiota in atlantic salmon (Salmo salar)

Atlantic salmon (Salmo salar) fed a carbohydrate-rich diet exhibit suboptimal growth performance, along with other metabolic disturbances. It is well known that gut microbes play a pivotal role in influencing metabolism of the host, and these microbes can be modified by the diet. The main goal of the present study was to determine the effect of feeding graded levels of digestible carbohydrates to Atlantic salmon on the distal intestine digesta microbiota at 3 sampling times (i.e., weeks 4, 8 and 12), during a 12-week trial. A low carbohydrate-to-high protein diet (LC/HP, 0% wheat starch), a medium carbohydrate-to-medium protein diet (MC/MP, 15% wheat starch) or a high carbohydrate-to-low protein diet (HC/LP, 30% wheat starch) was fed to triplicate fish tanks (27 to 28 fish per tank). We performed an in-depth characterization of the distal intestine digesta microbiota. Further, growth parameters, liver histology and the expression of genes involved in hepatic neolipogenesis in fish were measured. Fish fed a HC/LP diet showed greater hepatosomatic and viscerosomatic indexes (P = 0.026 and P = 0.018, respectively), lower final weight (P = 0.005), weight gain (P = 0.003), feed efficiency (P = 0.033) and growth rate (P = 0.003) compared with fish fed the LC/HP diet. Further, feeding salmon a high digestible carbohydrate diet caused greater lipid vacuolization, steatosis index (P = 0.007) and expression of fatty acid synthase (fas) and delta-6 fatty acyl desaturase (d6fad) (P = 0.001 and P = 0.001, respectively) in the liver compared with fish fed the LC/HP diet. Although, the major impact of feeding a carbohydrate-rich diet to Atlantic salmon in beta diversity of distal intestine digesta microbiota was observed at week 4 (HC/LP vs MC/MP and HC/LP vs LC/HP; P = 0.007 and P = 0.008, respectively) and week 8 (HC/LP vs MC/MP; P = 0.04), no differences between experimental groups were detected after 12 weeks of feeding. Finally, at the end of the trial, there was a negative correlation between lactic acid bacteria (LAB) members, including Leuconostoc and Lactobacillus, with hepatic steatosis level, the hepatosomatic and viscerosomatic indexes as well as the expression of fas and d6fad. Weissella showed negative correlation with hepatic steatosis level and the hepatosomatic index. Finally, further research to explore the potential use of LAB as probiotics to improve liver health in carnivorous fish fed fatty liver-induced diet is warranted.

Effects of endogenous potential probiotic Lactobacillus rhamnosus M2-4 on intestinal microflora and metabonomics in juvenile sea cucumber Apostichopus japonicus

As a lactic acid bacteria, Lactobacillus is an important probiotic used in aquaculture. Intestines play an important role in beneficial function of probiotic. But little is known about the mechanism of lactic acid bacteria effecting on the intestines of sea cucumber Apostichopus japonicus. Herein, the present study was designed to explore the effects of endogenous Lactobacillus rhamnosus M2–4 on the intestinal microflora and metabolism of juvenile A. japonicus with high-throughput sequencing and metabonomics technology. The basal diet was Sargassum thunbergii powder, which was added with M2–4 at 0, 105, 107 and 109 CFU / g to form the experimental diet respectively. The feeding experiment lasted for 30 days. The results showed that dietary M2–4 had a significant effect on intestinal microbial composition of sea cucumber. With the increase of dietary M2–4, the relative abundance of potential probiotics including Haloferula (Verrucomicrobia), Rhodobacteraceae and Lactobacillus were increased and the potential pathogens especially Vibrio were decreased. And dietary M2–4 at 109 CFU / g was beneficial to its self-colonization in the intestines of A. japonicus. Metabonomics analysis showed that the differential lipid metabolites were increased and lipid metabolism pathways were enriched with the increase of dietary M2–4. The highest enriched pathway in the intestines of A. japonicus were mTOR and PPAR signaling pathway and the mostly influenced pathways were glutathione and linoleic acid metabolism pathway. The correlation analysis of intestinal microflora and main differential metabolites indicated that the differential metabolites were mostly correlated to the strains of Flavobacteriaceae. These results shed some light on the mechanism of lactic acid bacteria Lactobacillus influencing the intestine of juvenile sea cucumber A. japonicus.

INVESTIGATION OF STARTER CULTURE PROPERTIES AND ANTIFUNGAL ACTIVITIES OF PICKLE-DERIVED LACTIC ACID BACTERIA

Fermented foods, which are widely consumed around the world, are of great importance for human health. Standard production should be carried out in order to extend the shelf life of fermented products and increase their positive effects on human health. Therefore, there is a need for starter cultures that can be used in the production of fermented products. In this study, antifungal activity on 9 yeast isolates, antibiotic resistance, growth at different temperatures, pH and salt concentrations, arginine hydrolysis and gas production from glucose of 5 lactic acid bacteria (Lactobacillus brevis, Lactobacillus plantarum, Lactobacillus paracasei, Pediococcus parvulus, Leuconostoc holzapfel) were investigated. The lactic acid bacteria have antifungal effects on all yeasts except Hanseniaspora opuntiae, Kazachstania exigua and Pichia fermentans, and they grow at 10 and 25 oC, 3.9 and 5 pH and 4% salt concentration. In addition, all of the isolates showed resistance to vancomycin. The results indicated that L. brevis, L. plantarum, L. paracasei strains can be used as starter cultures in term of standart pickle production and antifungal effect.

Improvement of Sanitary Quality of the <i>Digue</i> by Use of Lactic Starters

Digue is a traditional food obtained from the addition of the paste of roasted peanuts in pumpkin juice obtained by spontaneous fermentation. This spontaneous fermentation unfortunately contributes to its alteration by molds and certain pathogenic bacteria. The aim of this work is to use lactic starters to inhibit the growth of certain pathogenic germs during controlled fermentation. A total of 24 lactic acid bacteria were isolated from the samples of Digue collected in the locality of Gamboura in the Far North of Cameroon. The screening allowed to retaining 02 strains of lactic acid bacteria for their best antimicrobial activities. The molecular identification of these two strains showed that they belong to the species Lactobacillus casei and Pediococcus acidilactici. The use of these two 02 lactic acid bacteria during the controlled fermentation of the Digue contaminated by Aspergillus M2, Aspergillus M3, Escherichia coli ATCC 25922 and Salmonella enteritidis 155A showed that all the pathogen germs were totally inhibited by Lactobacillus casei after 21 days of fermentation. The same result was obtained with Pediococcus acidilactici on all molds and Escherichia coli ATCC 25922. At the end of this study, it appears that, the lactic acid bacteria Lactobacillus casei can be used to ensure the hygienic quality of the Digue after 21 days of fermentation.

In vivo evaluation of the toxicity of patulin degradation products produced by Lactobacillus casei YZU01

Patulin contamination of food products represents a significant problem in the food industry. Patulin degradation in food products by lactic acid bacteria can effectively eliminate the food safety challenge caused by this toxin. In the present study, the lactic acid bacterium Lactobacillus casei YZU01 was used to degrade patulin. The patulin degradation process by YZU01 was tracked and the final degradation products, having no identifiable characteristics in the ultraviolet spectrum, were collected. Analyses of mice administered patulin demonstrated that patulin can significantly decrease stomach and liver health indices, however, no significant effect on the organ indices were observed when mice were administered patulin degradation products. Furthermore, the level or activity of alanine transaminase, aspartate aminotransferase, malondialdehyde, glutathione, superoxide dismutase and glutathione peroxidase, which are involved in the oxidative stress response induced by patulin, were not significantly affected in mice administered the patulin degradation products. Our data indicate that patulin degradation products do not have patulin-like toxicity, and do not damage the intestinal tissues or induce changes in the intestinal microflora of mice. In summary, our analysis of the toxicity of the patulin degradation products produced by YZU01 indicates that the final degradation products are not toxic. Therefore, patulin detoxification strategies involving the use of L. casei YZU01 represent a good approach to limiting the risk caused by patulin ingestion in food products.

Effects of fortified starter culture containing Saccharomyces cerevisiae and Lactobacillus fermentum on microbial community structure and ethyl carbamate

Ethyl carbamate (EC) is a potential carcinogen that is mainly produced by the spontaneous reaction between urea and ethanol during Huangjiu (Chinese rice wine) brewing. In the traditional fermentation process, the starter plays an important role. However, the complex and diverse microorganisms in the starter make it a great challenge to control EC effectively. In this study, two isolated functional strains Saccharomyces cerevisiae G2 (with the capacity of urea utilization) and Lactobacillus fermentum d6 (with the capacity of acid EC-degrading enzymes producing) were used to fortify the starter culture, which regulated the metabolic activity of the microbial community and contributed to the control of EC content in Huangjiu. The high-throughput sequencing analysis showed that fungi (Saccharomyces, Aspergillus, Issatchenkia, and Rhiziopus) and bacteria (Lactobacillus, Streptophyta, and Aeromonas) were dominant microorganisms. Through the analysis of the correlation between the 34 main volatile compounds and the dominant microorganisms, it was found that lactic acid bacteria (Lactobacillus, Leuconostoc, and Lactococcus), Saccharomyces, and Torulaspora were positively correlated with volatile compounds (alcohols and esters). More importantly, fortified starter culture with these strains reduced the urea and EC content in Huangjiu significantly. The obtained results suggested that the EC content in Huangjiu could be regulated by changing the starter culture.

Research of fermentation processes of protein substrates by consortiums of lactic acid bacteria

The paper presents data on the assessment of the biotechnological activity of new consortiums of lactic acid bacteria Lactobacillus with the proteolytic activity. A comparative assessment of the biotechnological use of previously isolated strains of lactic acid bacteria and their combinations using methods that are highly effective in the technology of fermented food products is carried out. Biotechnological properties were studied on various food objects and substrates of animal and plant origin with a high protein content. As a result of the studies, consortiums of lactic acid bacteria, they can be recommended for inclusion in the composition of starter cultures for the production of functional products.

Production and optimization of lactic acid using Chlorella vulgaris as a source of fermentable sugar

The use of plant waste product for maximum sustainability has led to the search for bio based raw material such as Chlorella vulgaris which can make a tremendous contribution on the ecological and economical production of different organic acids like lactic acid. This study aimed to evaluate the enzymatic and or acidic hydrolysis of Chlorella vulgaris cell wall Intercellular starch as a source of fermentable sugar for lactic acid production. Lactic acid was produced through acid hydrolysis, enzyme hydrolysis and a combination of acid and enzyme hydrolysis of four different substrates. Each of the substrate was inoculated with a lactic acid bacterium (Lactobacillus plantarum) and a fungus (Rhizopus oryzae) while acid/enzyme hydrolysis was inoculated with mixed culture of the organism within a retention period of tendays. Results showed that the physico-chemical properties of C. vulgaris had a total carbohydrate of 17.4% and a reducing sugar of 24.0µg/ml. According to treatment, C. vulgaris had the highest reducing sugars (6.4 ± 0.2) and (4.4 ± 0.3) with Lactobacillus Enzyme Hydrolysis (LEH) and Rhizopus Enzyme Hydrolysis (REH) treatments, respectively indicating that C. vulgaris was the most hydrolyzed sample. Results of the optimization of various responses showed that using Corn Steep Liquor (CSL), REH day 2 treatment for fermentation at 370C for 48h were best combinations that yielded the optimal of Y1=0.249, Y2= 5.461 and Y3=33.704, respectively with a desirability of 0.619. The results indicated Chlorella vulgaris produced the highest lactic acid of about 20% signifying that its biomass contains high source of carbohydrate accessible for lactic acid production.

Timing of inoculation of Oenococcus oeni and Lactobacillus plantarum in mixed malo-lactic culture along with compatible native yeast influences the polyphenolic, volatile and sensory profile of the Shiraz wines

Malolactic fermentation (MLF) is a secondary wine fermentation resulting from lactic acid bacteria (Oenococcus oeni or Lactobacillus plantarum), especially in cool climates. MLF reduces acidity, improves body, mouthfeel, aroma complexity, and stabilizes the wine. Nevertheless, the traditional MLF using single culture is often associated with stuck fermentation, increased volatile acidity and color loss in wine. Thus, studies on mixed blend of L. plantarum and O. oeni to improve chemical and sensory profiles are gaining importance. The first study on different timing of inoculation of dual malo-lactic culture for the vinification of Shiraz wine aims to understand interactions between the wine cultures (Saccharomyces cerevisiae AAV2, L. plantarum Lp 1 and O. oeni Oo 1). The wines were compared based on chemical properties, phenolic and volatile profiles, and sensory analysis. The study highlighted that early or mid-inoculated MLF wines have higher anthocyanins, flavonoids, syringol, esters, vanillate derivatives, benzaldehyde, and free terpenes compared to traditional MLF wines. The wines were rated high for purple red colour, tannin, body, and overall acceptability. Hence, it was concluded that the inoculation of Lp 1 and Oo 1, either after 7 or 14 days of alcoholic fermentation by yeast AAV2, yield the desired quality Shiraz wine.

Lactic Acid Bacteria Are Prevalent in the Infrabuccal Pockets and Crops of Ants That Prefer Aphid Honeydew.

Ants are evolutionarily successful species and occupy diverse trophic and habitat niches on the earth. To fulfill dietary requirements, ants have established commensalism with both sap-feeding insects and bacteria. In this study, we used high-throughput sequencing of the bacterial 16S rRNA gene to characterize the bacterial composition and structure of the digestive tracts in three species of Formica ants and Lasius niger (Linnaeus)—species that predominantly feed on honeydew secreted by aphids. We found that bacterial communities displayed species- and colony-level signatures, and that bacterial communities in the infrabuccal pockets and crops were different from those in the midguts and hindguts. Lactobacillus and Wolbachia were dominant in the infrabuccal pockets and crops of workers, whereas Wolbachia was dominant in the midguts, hindguts and brood (larvae, pupae and cocoons). To learn more about the dominant Lactobacillus in ants, we assessed its prevalence in a wide range of aphid-tending ants using diagnostic PCR. We found that Lactobacillus was more prevalent in Formicinae than in Myrmicinae species. We also isolated four strains of lactic acid bacteria (Lactobacillus sanfranciscensis, Lactobacillus lindneri, Weissella cibaria and Fructobacillus sp.) from the infrabuccal pockets and crops of aphid-tending ants using a culture-dependent method. Two predominant lactic acid bacterial isolates, Lactobacillus sanfranciscensis (La2) and Weissella cibaria (La3), exhibited abilities in catabolizing sugars (sucrose, trehalose, melezitose and raffinose) known to be constituents of hemipteran honeydew. These findings contribute to further understanding the association between ants, aphids and bacteria, and provide additional information on the function of lactic acid bacteria in ants.

Isolation and Identification of Lactic Acid Bacteria from Traditional Fermented Milk "Dahi" Towards Developing Probiotic Dahi in Bangladesh

Objective: An attempt was made herein to isolate lactic acid bacteria (Lactobacillus sp. and Streptococcus thermophilus) from local Dahi to develop Dahi with isolated culture. Methods: These bacteria were identified by morphological characteristics, microscopic observation, catalase reaction, and finally examined by Polymerase Chain Reaction (PCR). Five Dahi samples (T1, T2, T3, T4, and T5) were prepared using the PCR culture. Dahi samples (T1, T2, and T3) were prepared using three Lactobacillus sp., T4 by Streptococcus thermophilus, and T5 by a combination of Lactobacillus sp. (T3) and Streptococcus thermophilus (T4) bacteria. Physicochemical, microbiological, and sensory properties were measured to assess the quality of the developed Dahi. The shelf life of the products was assessed through the determination of pH and titrable acidity of the samples measured on day 1 and 7, respectively. Results: Ash and protein percentage of T3 sample were significantly (P<0.05) better than others. The viable count was well above the minimum recommended value (106cfu/ml) in all the Dahi samples. Results of sensory properties namely taste, aroma, and overall acceptability of T3 and T4 Dahi were significantly (P<0.05) found superior compared to other samples. Conclusion: The lactic acid bacteria isolated and utilized in this study demonstrate great potential in the production of probiotic Dahi in future.

Insights into the evolution of Greek style table olives microbiome stored under modified atmosphere: Biochemical implications on the product quality

Olives are among the main components of the Mediterranean diet, rich in micronutrients and powerful antioxidants; their unique organoleptic properties and high nutritional value have increased table olive consumption worldwide. The purpose of this work was to study the microbiological and biochemical changes in Greek-style ‘Kalamata’ table olives, throughout different time-points of the shelf life of the product, packaged under modified atmosphere. Results revealed the prevalence of lactic acid bacteria (Lactobacillus spp.) from T0 and after the end of the product's shelf life, with L. parafarraginis being the dominant species, ranging from 37.8% to 49.8%. Concerning the eukaryotic populations, antagonistic interactions were observed among the dominant genera i.e. Pichia, Cladosporium and Saccharomyces. While Candida pseudolambica was the most abundant species up to T6, it was gradually displaced by Brettanomyces custersianus at T12 and T18. The significant decrease of total phenol content and a-tocopherol at T12, reflected the increment of Lactobacillus and yeast populations. The dominance of Lactobacillus spp. And B. custersianus at T18 was also depicted on the significant increase of hydroxytyrosol. The content of some fatty acids was shown to be affected by the yeast populations while the concentration of maslinic and oleanolic acid remained intact throughout storage. The combined approach of amplicon metabarcoding and biochemical analyses of naturally fermented olives packaged under modified atmosphere, enabled us to better understand the microbial competitions and interactions and the biochemical changes that accompany these transitions, hence, defining the quality of the end product offered to the consumer.