Lactobacillus Brevis Research Articles

Microbiological analysis of wine produced in the laboratory using pineapple and watermelon fruits fermented by Kloeckera apiculata

This research focuses on the microbiological analysis of wine produced in a laboratory using pineapple and watermelon fruits fermented by Kloeckera apiculata. The study aimed at evaluating the microbial composition, including yeast, bacteria, and mold, and the physicochemical properties of the wine during the fermentation process. The experiment was conducted using two batches of fruit, pineapple, and watermelon, separately fermented using Kloeckera apiculata. Samples were collected at different stages of fermentation and analyzed for microbial composition, pH, alcohol content, and total acidity. The yeasts, mold, and bacteria present were enumerated and isolated by spread plate techniques and incubated at room temperatures for 24h. Resultant colonies were enumerated and identified by a standard protocol. The results showed that Kloeckera apiculata dominated the microbial population during the fermentation process. No mold was isolated due to the low level of oxygen present in the fermentor. Three bacteria species were identified and confirmed during the fermentation to be Lactobacillus plantarum, Lactobacillus brevis, and Pediococcus species which are non-pathogenic bacteria and did not constitute any threat to health rather added a sour taste to the wine and also decreased the pH of the wine. The wine produced from pineapple had a higher alcohol content and lower acidity than the wine produced from watermelon. These findings demonstrate the potential of Kloeckera apiculata for the production of wine using tropical fruits and highlight the importance of microbiological analysis in the quality control of wine production.

Effect of Extraction Time on the Yield, Chemical Composition, and Antibacterial Activity of Hop Essential Oil Against Lactic Acid Bacteria (Lactobacillus brevis and Lactobacillus casei) Beer Spoilage.

Hop essential oil (EO) generates interest for its antioxidant and antimicrobial properties, in addition to the volatile compounds that are responsible for the hop aroma in beer. Thus, the objective of this study was to evaluate the chemical composition, EO yield, and antibacterial activity of hop essential oil from hops of the Chinook variety against lactic acid bacteria (Lactobacillus brevis and Lactobacillus casei) at different times of extraction. EO extraction was performed by hydrodistillation at different times. By analyzing the chemical composition by gas chromatography and mass spectrometry, the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined. The major compounds of hop EO were α-humulene, β-myrcene, and β-caryophyllene, and the extraction yields were 0.67, 0.78, and 0.85% mass of EO per mass of hops pelletized hops (m/m), for extractions of 90, 180, and 300min, respectively. The EO obtained in 90min was efficient against L. casei at 2.5mg/mL (MIC) and 5.0mg/mL (MBC), and the 300min one against L. brevis at 2.5mg/mL (MIC) and 25mg/mL (MBC). The antibacterial activity was affected by the chemical makeup of the oil, revealing that the hop EO extracted in 300min was the most efficient among the other extraction times.

Isolation and Identification of Lactic Acid Bacteria from Spontaneously Fermented Kunun-zaki using RAPD-PCR Analysis

Sixty lactic acid bacteria (LAB) were isolated from eighteen types of kunun-zaki produced naturally using millet, sorghum and maize each singly or in combinations with malted grains (millet, sorghum, maize, wheat and paddy rice) and characterized using conventional methods (biochemical and cultural) and molecular analyses. Seven morphotypes (Mt1-Mt7) were revealed among the 60 LAB isolates. Twenty LAB were selected based on the differences in their biochemical and physiological properties and these were subjected to DNA isolation and purification. The Agarose gel electrophoresis of the twenty (20) extracted DNA revealed very pure DNA electrophoretic pattern. The concentration of the DNA sample ranged between 0.7 mg/ml to 4.0 mg/ml and the purity index ranged from 1.5 to 1.9; indicating they were all very pure and can easily be used in Polymerase chain reaction (PCR) analysis. A highly polymorphic primer, OPB20 primer, was selected and used to analyze the 20 LAB DNA of which seven (7) isolates were identified to be Lactobacillus brevis, twelve (12) isolates were Lactobacillus plantarum and one isolate was identified as Lactobacillus acidophilus and these organisms could be potentially useful industrially.

Application of Lactobacillus spp. for the biological management of green mold (Penicillium digitatum) on sweet orange fruit under in vitro and storehouse conditions

ABSTRACT This study aimed to investigate the use of probiotic lactic acid bacteria including Lactobacillus brevis, L. plantarum, L. helveticus and L. delbrueckii from dairy products against Penicillium digitatum (green mold) on sweet orange fruit. Antifungal activity of Lactobacillus spp. was first assayed using bacterial cells through the overlay method against 105 spore/mL suspension of P. digitatum. Also, P. digitatum growth inhibition was measured in the PDA medium containing 15 and 30% cell-free supernatant (CFS) of Lactobacillus spp. Antifungal activity of Lactobacillus spp. was evaluated under storehouse conditions by treating wounded fruits with 108/mL cell suspension (CS) and 30% CFS of Lactobacillus spp., which then infected with 105/mL spore suspension of P. digitatum. The CS and CFS of L. plantarum had the best antifungal activity under both in vitro and in vivo conditions followed by L. helveticus, L. delbrueckii and L. brevis. L. plantarum. The 15 and 30% L. plantarum CFS were able to inhibit the growth of P. digitatum by 30.31%, 76.82% and 97.6% respectively, under in vitro conditions. Also, L. plantarum CS and 30% CFS reduced the growth of the P. digitatum on the fruit by 92.77 and 98.9% respectively, under storehouse conditions. The total content of all sugars of treated fruits with Lactobacillus spp., CS and CFS showed significant difference compared to untreated fruits. Therefore, the present study highlights the successful application of biological fungicides based on secondary compounds of Lactobacillus spp. due to greater stability of metabolites than bacterial cells in the environment.

Lactobacillus brevis alleviates the progress of hepatocellular carcinoma and type 2 diabetes in mice model via interplay of gut microflora, bile acid and NOTCH 1 signaling.

Type 2 diabetes (T2DM) clinically exhibits a higher incidence of hepatocellular carcinoma (HCC), contributing to a lousy prognosis in patients harboring both diseases. Microflora-based therapy draws attention with low side effects. Accumulating evidence shows that Lactobacillus brevis can improve blood glucose and body weight of the T2DM mice model and reduce several cancer incidences. However, the therapeutic effect of Lactobacillus brevis in affecting the prognosis of T2DM+HCC remains unknown. In this study, we aim to explore this question via an established T2DM+HCC mice model. We observed a significant alleviation after the probiotic intervention. Lactobacillus brevis improves blood glucose and insulin resistance and ameliorates Mechanically. Combined with a multi-omics approach including 16SrDNA, GC-MS, and RNA-seq, we identified distinct intestinal microflora composition and metabolites after Lactobacillus brevis intervention. Furthermore, we found that Lactobacillus brevis delayed disease progression by regulating MMP9 and NOTCH 1 signaling pathways, potentially through gut microflora and BA interaction. This study indicates that Lactobacillus brevis may improve the prognosis of T2DM + HCC, providing novel therapeutic opportunities via targeting intestinal flora for patients with T2DM+HCC.

Microbial Community and Fermentation Quality of Alfalfa Silage Stored in Farm Bunker Silos in Inner Mongolia, China

Alfalfa is conserved in silo-type bunkers in the cold and humid regions of Inner Mongolia, China. Its quality is essential to ensure a healthy and sustainable dairy production. However, the impact of environmental factors on the microbiota and fermentation products of alfalfa silage remains unclear. The present research examined changes in the microbiota and fermentation products and their association with environmental parameters in 72 samples collected from 12 farms located at 4 different latitudes and longitudes across four regions. The samples were labeled with distinct codes, A, B, and C, from the cold–rainy region, D, E, and F, from the warm–rainy region, G, H, and I from the cold–dry region, and J, K, and L from the warm–dry region. The lactic acid levels ranged from 14.25 to 24.27 g/kg of DM across all samples. The pH and concentrations of NH3-N and butyric acid in samples A, B, and H were higher (p < 0.01) than in the other samples. Samples D and E had higher acetic acid concentrations and 1, 2-propanediol content (p < 0.01). The fresh material was dominated by Pantoea and Pseudomonas, whereas Lactobacillus was the most dominant genus in all silages, except for the B silage. The A, B, and H silages contained more Clostridium but less Lactobacillus than the other silages. The lactic acid levels were strongly associated with Lactobacillus plantarum, Weissella paramesenteroides, Lactobacillus acetotolerans, Pedobacter borvungensis, and Lactobacillus brevis (p < 0.01). In contrast, the pH and the NH3-N and butyric acid concentrations were strongly associated (p < 0.01) with the presence of Clostridium estertheticum. A correlation analysis revealed that precipitation, temperature, longitude, and latitude were the most critical factors influencing epiphytic microbes in the fresh material. After silage fermentation, low-temperature conditions significantly affected the fermentation products and microbial community composition. In conclusion, the microbial community of silages is distinctive in cold and humid regions, and climatic parameters ultimately affect the microbiota and fermentation products. Furthermore, the findings of this study demonstrate that Illumina MiSeq sequencing combined with environmental factor assessment might provide new information about the microbiota composition and fermentation quality of silages, facilitating the achievement of high-quality silage.

Extraction and optimization of phenolic compounds from butterbur plant (Petasites hybridus) by ultrasound-assisted extraction and determination of antioxidant and antimicrobial activity of butterbur extracts

Butterbur (Petasites hybridus), which is a perennial herb native to Europe, Asia and North America, is used as food in the Black Sea region of Turkey. In this study, it was aimed to identify the natural microflora of the root, stem and leaf parts of the butterbur plant, to optimize the extraction of phenolic compounds in these parts by ultrasound-assisted extraction (UAE) using the response surface methodology (RSM), and to determine the antioxidant and antimicrobial activities of these extracts. For this purpose, the effects of temperature (30–70 °C), extraction time (30–60 min) and ethanol concentration (0–70%) on total phenolic compounds (TPC) of phenolic extracts obtained from the butterbur plant parts were determined. As a result of the extractions carried out at optimum conditions, TPC (4.73, 0.64 and 3.78 μg GAE/mg extract), ABTS (17.57, 7.57 and 12.84 µg TE/mg extract), DPPH (2.51, 1.84 and 2.27 µg TE/mg extract) and FRAP (3.64, 2.95 and 3.14 µg TE/mg extract) values of the extracts obtained from root, stem and leaf were determined. Antimicrobial activity of the root, stem and leaf extracts were investigated on Escherichia coli O157:H7, Salmonella Typhimurium, Bacillus cereus, Staphylococcus aureus, Lactobacillus plantarum and Lactobacillus brevis microorganisms by the 96-well microtiter plate method and also disc diffusion method. Minimum inhibition concentration (MIC) values of the extracts ranged between 0.39 and 87.50 mg/mL for all extracts and all tested microorganisms, while inhibition zone diameters ranged between 6.05 and 20.30 mm. In conclusion, extracts obtained from the butterbur plant can extend the shelf life of food products due to their antimicrobial activities.

Ketonization of Ginsenoside C-K by Novel Recombinant 3-β-Hydroxysteroid Dehydrogenases and Effect on Human Fibroblast Cells.

The ginsenoside compound K (C-K) (which is a de-glycosylated derivative of major ginsenosides) is effective in the treatment of cancer, diabetes, inflammation, allergy, angiogenesis, aging, and has neuroprotective, and hepatoprotective than other minor ginsenosides. Thus, a lot of studies have been focused on the conversion of major ginsenosides to minor ginsenosides using glycoside hydrolases but there is no study yet published for the bioconversion of minor ginsenosides into another high pharmacological active compound. Therefore, the objective of this study to identify a new gene (besides the glycoside hydrolases) for the conversion of minor ginsenosides C-K into another highly pharmacological active compound. Lactobacillus brevis which was isolated from Kimchi has showed the ginsenoside C-K altering capabilities. From this strain, a novel potent decarboxylation gene, named HSDLb1, was isolated and expressed in Escherichia coli BL21 (DE3) using the pMAL-c5X vector system. Recombinant HSDLb1 was also characterized. The HSDLb1 consists of 774 bp (258 amino acids residues) with a predicted molecular mass of 28.64 kDa. The optimum enzyme activity was recorded at pH 6.0-8.0 and temperature 30 °C. Recombinant HSDLb1 effectively transformed the ginsenoside C-K to 12-β-hydroxydammar-3-one-20(S)-O-β-D-glucopyranoside (3-oxo-C-K). The experimental data proved that recombinant HSDLb1 strongly ketonized the hydroxyl (-O-H) group at C-3 of C-K via the following pathway: C-K → 3-oxo-C-K. In vitro study, 3-oxo-C-K showed higher solubility than C-K, and no cytotoxicity to fibroblast cells. In addition, 3-oxo-C-K induced the inhibitory activity of ultraviolet A (UVA) against matrix metalloproteinase-1 (MMP-1) and promoted procollagen type I synthesis. Based on these expectations, we hypothesized that 3-oxo-C-K can be used in cosmetic products to block UV radiations and anti-ageing agent. Furthermore, we expect that 3-oxo-C-K will show higher efficacy than C-K for the treatment of cancer, ageing and other related diseases, for which more studies are needed.

Revealing the correlation between the bacterial communities and physicochemical properties of ZaoPoCu, a traditional fermented food from Hainan Island

ABSTRACT The bacterial communities of Zaopocu (ZPC), a tropical specialty fermented food in Hainan Island, were characterized in this study using high-throughput sequencing. Firmicutes and Proteobacteria were the two dominant phyla. The primary genus in ZPC_A was Weissella, while ZPC_B and ZPC_C had Lactobacillus as the dominant genus. The biomarker lactic acid bacteria (LAB) in ZPC_A were Lactobacillus brevis, Weissella confusa, and Leuconostoc citreum, whereas Lactobacillus amylolyticus and Lactobacillus helveticus were significantly higher in ZPC_B. In contrast, Lactobacillus pontis and Lactobacillus fermentum were the core LAB in ZPC_C. ZPC_A has the highest value of titratable acid (TA), amino acid, and lactic acid. TA had the most powerful influence on the structure of the bacterial communities, whereas salinity had a negligible effect. It is worth noting that ZPC may also faces food safety issue because opportunistic pathogenic bacteria like Stenotrophomonas and genes closely associated with Staphylococcus aureus infection were highly detected.

Dysregulated cellular redox status during hyperammonemia causes mitochondrial dysfunction and senescence by inhibiting sirtuin-mediated deacetylation.

Perturbed metabolism of ammonia, an endogenous cytotoxin, causes mitochondrial dysfunction, reduced NAD+ /NADH (redox) ratio, and postmitotic senescence. Sirtuins are NAD+ -dependent deacetylases that delay senescence. In multiomics analyses, NAD metabolism and sirtuin pathways are enriched during hyperammonemia. Consistently, NAD+ -dependent Sirtuin3 (Sirt3) expression and deacetylase activity were decreased, and protein acetylation was increased in human and murine skeletal muscle/myotubes. Global acetylomics and subcellular fractions from myotubes showed hyperammonemia-induced hyperacetylation of cellular signaling and mitochondrial proteins. We dissected the mechanisms and consequences of hyperammonemia-induced NAD metabolism by complementary genetic and chemical approaches. Hyperammonemia inhibited electron transport chain components, specifically complex I that oxidizes NADH to NAD+ , that resulted in lower redox ratio. Ammonia also caused mitochondrial oxidative dysfunction, lower mitochondrial NAD+ -sensor Sirt3, protein hyperacetylation, and postmitotic senescence. Mitochondrial-targeted Lactobacillus brevis NADH oxidase (MitoLbNOX), but not NAD+ precursor nicotinamide riboside, reversed ammonia-induced oxidative dysfunction, electron transport chain supercomplex disassembly, lower ATP and NAD+ content, protein hyperacetylation, Sirt3 dysfunction and postmitotic senescence in myotubes. Even though Sirt3 overexpression reversed ammonia-induced hyperacetylation, lower redox status or mitochondrial oxidative dysfunction were not reversed. These data show that acetylation is a consequence of, but is not the mechanism of, lower redox status or oxidative dysfunction during hyperammonemia. Targeting NADH oxidation is a potential approach to reverse and potentially prevent ammonia-induced postmitotic senescence in skeletal muscle. Since dysregulated ammonia metabolism occurs with aging, and NAD+ biosynthesis is reduced in sarcopenia, our studies provide a biochemical basis for cellular senescence and have relevance in multiple tissues.

Synergistic strategy for the enhancement of biohydrogen production from molasses through coculture of Lactobacillus brevis and Clostridiumsaccharobutylicum

This study aimed to evaluate the capacity of different inoculum sources and their bacterial diversity to generate hydrogen (H2). The highest Simpson (0.7901) and Shannon (1.581) diversity indexes for H2-producing bacterial isolates were estimated for sewage inocula. The maximum cumulative H2 production (Hmax) was 639.6 ± 5.49 mL/L recorded for the sewage inoculum (SS30) after 72 h. The highest H2-producing isolates were recovered from SS30 and identified as Clostridium saccharobutylicum MH206 and Lactobacillus brevis MH223. The Hmax of C. saccharobutylicum, L. brevis, and synergistic coculture was 415.00 ± 24.68, 491.67 ± 15.90, and 617.67 ± 3.93 mL/L, respectively. The optimization process showed that the Hmax (1571.66 ± 33.71 mL/L) with a production rate of 58.02 mL/L/h and lag phase of 19.33 h was achieved by the synergistic coculture grown on 3% molasses at 40 °C, pH 7, and an inoculum size of 25% (v/v). This study revealed the economic feasibility of the synergistic effects of coculture on waste management and biohydrogen production technology.

Optimization of process parameters for GABA and L-DOPA production on fermented coconut drink

Gamma-aminobutyric acid (GABA) and levodopa (L-DOPA) are compounds that can potentially treat hypertension and Parkinson’s diseases. The purpose of this study was to optimize the fermentation parameters for GABA and L-DOPA production by Lactobacillus acidophilus co-cultured with Lactobacillus brevis (LALB) in mature coconut water (MCW). In this study, the response surface methodology (RSM) with central composite design (CCD) was applied to optimize the concentration of sucrose, culture temperature and incubation time. The optimum conditions for the yield of GABA and L-DOPA were found to be: 1 g sucrose at 27oC for 28 hrs of incubation time under static conditions with the predicted accuracy of 95.4% (352 mg GABA/L and 94.7% (89 mg L-DOPA/L). This work was conducted to add value to the by-product of the coconut milk industry through the production of fermented coconut drinks. The MCW fermented with LALB offers a potential functional drink for hypertension and Parkinson’s disease treatment and prevention measures.

Development of an oil-sealed anaerobic fermentation process for high production of γ-aminobutyric acid with Lactobacillus brevis isolated by directional colorimetric screening

γ-aminobutyric acid (GABA) is an important inhibitory neurotransmitter in the brain with many physiological functions. Therefore, this work establishes an efficient biosynthesis process to achieve the high production of food-grade GABA. Firstly, we adopted a directional colorimetric screening method and then obtained the strain Lactobacillus brevis (Lb. brevis) CGMCC 24975 with 22.61 g/L GABA in shake flasks, much higher than Lb. brevis ATCC 367 (3.07 g/L) due to its more efficient and stable expression of its glutamate decarboxylase (GAD) system. After exploring the effects of optimal fermentation conditions and oxygen on GABA production, we found that anaerobic fermentation could increase GABA production by up-regulating gad operon expression and activating GADase. Finally, we developed an oil-sealed anaerobic fermentation process with 157.90 g/L GABA in a 5 L bioreactor, which was 6.98-fold of that in shake flasks. This work includes a complete process from screening GABA-producing strains to developing efficient fermentation processes, laying the foundation for producing food-safe GABA.

Effects of probiotics on antioxidant activity, flavor compounds and sensory evaluation of Rosa roxburghii Tratt

Fermentation is an effective way to improve the comprehensive quality of Rosa roxburghii Tratt (RRT). In this study, the flavor compounds in RRT that fermented by different probiotics (Lactobacillus acidophilus, Lactobacillus brevis, and Lactobacillus plantarum) were analyzed by headspace - gas chromatography - ion mobility spectrometry (HS - GC - IMS). Overall, 87 flavor compounds were identified through HS - GC - IMS, which included aldehydes, alcohols, esters, ketones, and other compounds (including their monomers and dimers). The key flavor compounds and maximum potential difference markers were screened out and combined with sensory evaluation to analyze the effects of probiotics on the flavor of RRT. The results showed that probiotics could improve the flavor of RRT, and Lactobacillus acidophilus had the largest effect (about 13%) on RRT flavor. Moreover, after RRT fermentation by probiotics, the content of SOD in RRT increased by 19.18%–29.68%, and the scavenging capacity of DPPH, ABTS and OH free radical increased by more than 10%. In short, probiotics fermentation of RRT can effectively improve its flavor and prebiotic value, thereby providing a reference for RRT processing and flavor research.

Testing of the Efficacy of Bee Probiotic Lactobacilli Under In Vivo Conditions

Abstract American foulbrood is amongst the most dangerous diseases of the bee-family affecting many honeybee colonies worldwide. In countries of European Union, based on veterinary legislation, the bee colonies tested positive to American foulbrood are eradicated with high economic losses. It is therefore necessary to look for effective prevention, especially by the using of natural ingredients such as probiotics. In this study, we used lactobacilli isolated from digestive tracts of adult healthy honey bees and selected based on their good probiotic properties and ability to inhibit the growth of Paenibacillus larvae. These isolates were identified as Lactobacillus brevis and Lactobacillus plantarum. Night cultures of both strains were used for the preparation of probiotic suspensions and pollen was selected as an appropriate carrier for application of probiotic lacto-bacilli to the hives. Half a litre of pollen suspension was prepared for each hive. The suspension for experimental hives contained probiotic lactobacilli in concentration of 107–108 CFU.ml−1. Bees in control hives received pollen suspension without addition of probiotic lacto-bacilli. The suspensions were supplied to bees three times, once a week. Before and during administration of probiotics, samples of honey bees from each hive were taken every week and numbers of lactobacilli, P. larvae, enterobacteria and coliform bacteria were determined in their digestive tracts. Four weeks after the first administration of probiotic-pollen solution the numbers of lactobacilli were increased approximately by 0.5 log. Before starting this experiment, P. larvae (approx. 107 CFU.ml−1) were detected in digestive tracts of honey bees. In the experimental group after 3 weeks and in the control group after 4 weeks, no viable counts of P. larvae were found. The numbers of enterobacteria, coliform bacteria and Bacillus sp. decreased in both groups. During the experiment the health and condition of the hives were monitored. In addition, also monitored were: the development of the bee colony, the number of dead bees, the amount of hive debris, the aggressiveness of the bees, and the amount of honey spun; later during the autumn treatment also the fall of Varroa jacobsoni was noted. In the experimental and control groups, we recorded a decrease in the amount of hive debris. Only in the experimental group was a slightly above-average development of the bee colony, slightly above-average honey yields and a 70 % lower drop of Varroa mites. Based on these results, we assumed that the probiotic-pollen solution had a positive influence on the composition of microbiota in bee digestive tracts and it can increase resistance to P. larvae. It also had a positive effect on the health and condition of the bee colony. Probiotic-free pollen solution showed similar but weaker effects.

Effects of probiotic supplement Lactobacillus Plantarum CECT7485 and Lactobacillus Brevis CECT7480 on sleep quality in patients with anxiety and depression comorbidity

IntroductionRecent studies have supported that Lactobacillus plantarum can reduce the severity of anxiety and depression. However, previous studies did not focus on the sleep quality. This study determines whether Lactobacillus Plantarum CECT7485 and Lactobacillus Brevis CECT7480 reduce the severity of insomnia, and improves sleep quality in patients who comorbidity of depression and anxiety disorders.ObjectivesAn assessment of insomniac effects a probiotic supplement containing Lactobacillus Plantarum CECT7485 and Lactobacillus Brevis CECT7480 (PLANTARUM) in patients with anxiety and depression comorbidity undergoing treatment with selective serotonin reuptake inhibitors (SSRI) antidepressants.MethodsSixty patients with mixed anxiety and depressive disorder (according to ICD-10 diagnostic criteria F41.2) were included in an 8-week open label study. Thirty participants received either SSRI antidepressants with PLANTARUM at a dose of 1.0 × 109 CFU once per day and thirty patients received SSRI antidepressants only. The severity of insomnia was assessed using Insomnia Severity Index (ISI). The severity of depressive symptoms was rated using Hamilton Depressive Rating Scale (HDRS). The severity of anxiety symptoms was assessed using Hamilton Anxiety Rating Scale (HAM-A) and General Anxiety Disorder Scale (GAD-7).ResultsAfter 8 weeks intervention, a significant reduction of ISI total score (from 22,1±2,8 to 14,1±2,1) was detected in patients with anxiety and depression who prescribed SSRI antidepressants and PLANTARUM (p˂0,05), compared with participants who didn’t receive probiotics (p>0,05). Also, we detected a significant improve sleep quality of insomniac patients with comorbidity of anxiety and depressive symptoms (p˂0,05) who received SSRI antidepressants and probiotic supplement Lactobacillus Plantarum CECT7485/Lactobacillus Brevis CECT7480.ConclusionsThe present data illustrated that probiotic supplement Lactobacillus Plantarum CECT7485 and Lactobacillus Brevis CECT7480 is a feasible for adjunctive to SSRI antidepressants intervention for insomniac patients with anxiety and depressive comorbidityDisclosure of InterestNone Declared

The effect psychobiotics on anxiety symptoms

IntroductionPsychobiotics are a group of probiotics that affect the central nervous system related functions and behaviors mediated by the gut-brain-axis via immune, humoral, neural, and metabolic pathways to improve not only the gastrointestinal function but also the antidepressant and anxiolytic capacity.ObjectivesAn assessment of psychobiotic and anti-anxiety effects a probiotic supplement containing Lactobacillus Plantarum CECT7485 and Lactobacillus Brevis CECT7480 (PLANTARUM) in patients with anxiety undergoing treatment with selective serotonin reuptake inhibitors (SSRI) antidepressants.MethodsSixty patients with mixed anxiety and depressive disorder (according to ICD-10 diagnostic criteria F41.2) were included in an 8-week open label study. Thirty participants received either SSRI antidepressants with PLANTARUM at a dose of 1.0 × 109 CFU once per day and thirty patients received SSRI antidepressants only. The severity of anxiety symptoms was assessed using Hamilton Anxiety Rating Scale (HAM-A) and General Anxiety Disorder Scale (GAD-7).ResultsAfter 8 weeks intervention, a significant reduction of HAM-A total score (from 37,8±5,3 to 23,6±4,4) was detected in patients with anxiety who prescribed SSRI antidepressants and PLANTARUM (p˂0,05), compared with participants who didn’t receive probiotics (p>0,05). Also, a significant reduction of GAD-7 total score (from 21,7±3,3 to 12,5±2,4) was detected in patients with anxiety symptoms who received SSRI antidepressants and PLANTARUM (p˂0,01), compared with patients who didn’t intake probiotics (p>0,05).ConclusionsThe present data illustrated that probiotic supplement PLANTARUM is a feasible for adjunctive to SSRI antidepressants intervention for anxiety treatment.Disclosure of InterestNone Declared

High Production of γ-Aminobutyric Acid by Activating the xyl Operon of Lactobacillus brevis.

γ-Aminobutyric acid (GABA) is an inhibitory neurotransmitter with important physiological functions such as sleep assistance and anti-depression. In this study, we developed a fermentation process for the high-efficiency production of GABA by Lactobacillus brevis (Lb. brevis) CE701. First, xylose was found as the optimal carbon source that could improve the GABA production and OD600 in shake flasks to 40.35 g/L and 8.64, respectively, which were 1.78-fold and 1.67-fold of the glucose. Subsequently, the analysis of the carbon source metabolic pathway indicated that xylose activated the expression of the xyl operon, and xylose metabolism produced more ATP and organic acids than glucose, which significantly promoted the growth and GABA production of Lb. brevis CE701. Then, an efficient GABA fermentation process was developed by optimizing the medium components using response surface methodology. Finally, the production of GABA reached 176.04 g/L in a 5 L fermenter, which was 336% higher than that in a shake flask. This work enables the efficient synthesis of GABA using xylose, which will provide guidance for the industrial production of GABA.

Inactivation of Lactobacillus brevis cells and Bacillus cereus spores as influenced by pressure, shear, thermal, and valve geometry

ABSTRACT This study investigated the influence of pressure, shear, temperature, and their interactions on the inactivation of two bacteria – Lactobacillus brevis and Bacillus cereus spores. Cell suspension of L. brevis (1.6 × 1010 CFU/mL) and spore suspension of B. cereus (3.2 × 108 CFU/mL) were suspended in HEPES buffer (pH 7.3) and subjected to ultra-shear treatment (UST) at 400 MPa, process temperatures of 40 and 70°C, and flow rate of 0.0012 ± 0.0003 kg/s. In separate equipment, thermal (0.1 MPa-70°C-0/5 min) and high-pressure processing (HPP-400 MPa-40°C and 70°C-0/5 min) experiments were carried out to evaluate thermal only, pressure only, and combined pressure-thermal effects. Pressure-only treatment at 400 MPa for 0 min (come-up time) at 70°C resulted in 8.4 and 2.3 log reductions of L. brevis cells and B. cereus spores, respectively. After UST treatment at 70°C, L. brevis and B. cereus spores were reduced by 7.1 and 1.6 logs, respectively. Both strains showed different sensitivities to thermal, pressure, shear, and their combinations. B. cereus spores were relatively more resistant to HPP and UST treatments. Three valve geometries, namely, ultra-shear valve, needle valve, and tubular valve, were used to compare UST treatment effect on L. brevis and B. cereus spores at 40 and 70°C. UST treatment using the ultra-shear valve produced inactivation of 2.0 and 7.1 log cycles for L. brevis during 40 and 70°C process temperatures, respectively, which was relatively higher than needle valve and tubular valve. This higher inactivation could be attributed to the smaller valve gap and higher shear rate in the ultra-shear valve. Further, the comparatively higher inactivation at 70°C UST (7.1 log) emphasized the role of temperature on inactivation during UST. For both L. brevis and B. cereus, the inactivation was least in the tubular valve with relatively lesser shear rate, which indicated the desirable contribution of high shear rate for microbial inactivation. The information from this study contributes to the development of safe harbor UST process conditions for liquid foods.

Effect of UV Filters during the Application of Pulsed Light to Reduce Lactobacillus brevis Contamination and 3-Methylbut-2-ene-1-thiol Formation While Preserving the Physicochemical Attributes of Blonde Ale and Centennial Red Ale Beers

Pulsed light (PL) is a novel, non-thermal technology being used to control the microbial spoilage of foods and beverages. Adverse sensory changes, commonly characterized as "lightstruck", can occur in beers when exposed to the UV portion of PL due to the formation of 3-methylbut-2-ene-1-thiol (3-MBT) upon the photodegradation of iso-α-acids. This study is the first to investigate the effect of different portions of the PL spectrum on UV-sensitive beers (light-colored blonde ale and dark-colored centennial red ale) using clear and bronze-tinted UV filters. PL treatments with its entire spectrum, including the ultraviolet portion of the spectrum, resulted in up to 4.2 and 2.4 log reductions of L. brevis in the blonde ale and centennial red ale beers, respectively, but also resulted in the formation of 3-MBT and small but significant changes in physicochemical properties including color, bitterness, pH, and total soluble solids. The application of UV filters effectively maintained 3-MBT below the limit of quantification but significantly reduced microbial deactivation to 1.2 and 1.0 log reductions of L. brevis at 8.9 J/cm2 fluence with a clear filter. Further optimization of the filter wavelengths is considered necessary to fully apply PL for beer processing and possibly other light-sensitive foods and beverages.