Ação antimicrobiana dos compostos voláteis do óleo essencial das folhas secas de Croton blanchetianus Baill

O Croton blachetianus, popularmente denominado marmeleiro, é um arbusto rico em metabólitos secundários que apresenta diversas atividades biológicas. O objetivo desse estudo foi determinar a composição dos compostos voláteis do óleo essencial das folhas secas de C. blanchetianus e sua ação antimicrobiana (dose mínima inibitória – DMI do vapor) sobre as cepas das bactérias ácido-lácticas (BAL), Weissella viridescens e Leuconostoc mesenteroides, deteriorantes de produtos cárneos. O óleo essencial das folhas secas de C. blanchetianus foi extraído pela técnica de hidrodestilação e os compostos voláteis foram analisados pela técnica de headspace, por cromatografia gasosa. A dose mínima inibitória na fase vapor foi definida como a dose mínima de solução de óleo essencial de C. blanchetianus em DMSO 5% cujo vapor inibe completamente o crescimento das BAL, durante 48 horas. Posteriormente, o efeito bactericida e bacteriostático foi determinado. Os compostos majoritários encontrados foram os terpenos eucaliptol (32,94%) e D-α-Pineno (29,43%). A dose mínima inibitória foi de 0,32g/mL, para ambos os microrganismos. O efeito bactericida para W. viridescens foi observado pela ação do vapor da solução de 0,32 g/mL e, para a L. mesenteroides, o efeito bacteriostático e bactericida foi pela ação do vapor da solução de 0,40 g/mL e 0,57 g/mL, respectivamente. Assim, foi possível observar a presença de terpenos como compostos majoritários na análise por headspace, bem como a atividade antimicrobiana, bacteriostática e bactericida do óleo essencial das folhas secas de C. blanchetianus frente as BAL W. viridescens e L. mesenteroides.

The effect of combination probiotic lactobacillus brevis and leuconostoc mesenteroides on tgf-β and il-12 expression in ileum

Background: Asthma is a disease of the respiratory tract in the form of chronic inflammation. Chronic inflammation is one of them characterized by the remodeling of the airways mediated by the anti-inflammatory cytokine TGF-β. In addition there are also several immune cells that play a role such as macrophages, dendritic, neutrophils as producers of IL-12. The presence of the gut-lung axis allows the spread of inflammatory cytokines from the lungs to the intestines and vice versa. Lactobacillus brevis and Leuconostoc mesenteroides have the potential to modulate the immune system through its colonization of the gut. The study aimed to look at the effect of probiotics combined Lactobacillus brevis and Leuconostoc mesenteroides on the expression of TGF-β and IL-12 in the asthma model mouse ileum. Method: This experimental post-test only control group design study used 18 Sprague-Dawley mice. The mice were divided into 3 groups at random: control group (KI), asthma treatment (KII), asthma treatment with a combination of Lactobacillus brevis and Leuconostoc mesenteroides (KIII). Sensitization of asthma with OVA through intraperitoneal injection on days 0 and 14 and through inhalation on days 21 -63. Administration of combination probiotics per oral per day on days 21-63 after inhalation of OVA. The ileum network was taken on the 64th day and measured the expression of TGF-βand IL-12 with immunohistochemical methods and analyzed the percentage proportion of TGF-βand IL-12. Data analysis were conducted by One way ANOVA test and continued post hoc tests. Results: The percentage calculation of the proportion of TGF-βin thecontrol group (KI), asthma group (KII), and the combination group of L.brevis and L.mesenteroides (KIII) is 22.4 ± 15.27; 1.6 ± 2.12; 19.4 ± 6.65. While the percentage calculation of il-12 proportion in each group consecutively were 24.3 ± 19.67; 64.63 ± 9.90; 51 ± 16.62. One way ANOVA Test results on the percentage proportion of TGF-βhave a p value of 0.013 (p<0.05) which means there is a significant difference in the entire group. Furthermore, the Post Hoc Games-Howell test was conducted and obtained a p value of 0.003 (p<0.05) between the asthma group (KII) and the combination group of L.brevis and L.mesenteroides (KIII) which means there are significant differences between the two groups. One way ANOVA Test results on the percentage proportion of IL-12 have a p value of 0.011 (p<0.05) which means there is a significant difference in the entire group. Furthermore, the Post Hoc LSD test was conducted and obtained a p value of 0.001 (p<0.05) between the control group Post Hoc analyses was conducted and obtained a p value of 0.002 (p<0.05) with number of errors was 11.353 between the control group (KI) and asthma group (KII) which means there are significant differences between the two groups. Conclusion: The probiotic administration of lactobacillus brevis and Leuconostoc mesenteroides had no effect on the expression of TGF-β and had no effect on il-12 expression in the asthma model mouse ileum. It is necessary to do research on mice with asthma using combinations with other bacteria in order to get maximum effect. Bangladesh Journal of Medical Science Vol. 21(1) 2022 Page : 175-183

Prebiotic activities of dextran from Leuconostoc mesenteroides SPCL742 analyzed in the aspect of the human gut microbial ecosystem

Investigation of the prebiotic activities of LM742 dextran produced by Leuconostoc mesenteroides SPCL742 in the aspect of the human gut microbial ecosystem focusing on microbiome and metabolome changes in in vitro colonic fermentation.

Chufa Drink: Potential in Developing a New Plant-Based Fermented Dessert

Plant-based foods with desirable texture and nutritional value have attracted considerable interest from consumers. In order to meet the growing demand for more sustainable and health-focused products, new sources for plant-based products are needed. In this study, we aimed to develop an innovative plant-based dessert based on the underutilized crop chufa tubers (Cyperus esculentus). The chufa extract was fermented with plant-adapted lactic acid bacteria and formulated with the purpose of imitating the Danish summer dessert “cold butter-milk soup”. The effect of various bacterial fermentations and formulations on steady and oscillatory rheology, stability, dry matter, pH, and sugar profile of the product were studied and compared to a commercial cold buttermilk soup sample. A strain of Leuconostoc mesenteroides was found to create the most similar taste to a commercial sample. By adding lemon juice, sucrose, xanthan gum, and vanilla to the fermented chufa drink, the drink was found to mimic the pH, texture, acid profile, and stability of a commercial dairy-based sample, while containing a lower concentration of carbohydrates.

Assessment of the Spoilage Microbiota during Refrigerated (4 °C) Vacuum-Packed Storage of Fresh Greek Anthotyros Whey Cheese without or with a Crude Enterocin A-B-P-Containing Extract

Although fresh whey cheeses are prone to rapid deterioration, mainly by psychrotrophic Gram-negative bacteria and lactic acid bacteria (LAB), data on the specific spoilage species in traditional Greek whey cheeses are scarce. Therefore, this study quantified growth and characterized the primary spoilage bacteria in fresh Anthotyros whey cheeses stored at 4 °C in a vacuum for 40 days, without or with an added 5% (v/w) of an enterocin A-B-P crude extract (CEntE). Psychrotrophic Pseudomonas spp., Aeromonas spp., Hafnia spp. and Serratia spp. grew faster than LAB during early storage. However, LAB outgrew the Gram-negative bacteria and prevailed by mid to late storage in all cheese batches, causing a strong or milder batch-dependent natural acidification. Two major non-slime-producing and two minor biotypes of Leuconostoc-like bacteria, all identified as Leuconostoc mesenteroides by 16S rRNA sequencing, dominated the LAB association (76.7%), which also included four subdominant Carnobacterium maltaromaticum biotypes (10.9%), one Leuconostoc lactis biotype (3.3%) and few Lactococcus (1.6%), mesophilic Lactobacillus (0.8%) and Enterococcus (0.8%). Growth and distribution of LAB and Gram-negative species were strongly batch-dependent and plant-dependent. The CEntE neither retarded growth nor altered the whey cheese spoilage association but enhanced LAB growth and the declines of Gram-negative bacteria by late storage.

Leuconostoc mesenteroides and Pediococcus pentosaceus Non-Alcoholic Pearl Millet Beverage Enriched with Moringa oleifera Leaf Powder: Nutritional and Sensory Characteristics

Non-alcoholic cereal beverages (NACB) are usually produced through uncontrolled fermentation driven by a cocktail of bacteria resulting in final product variability. Hence, to commercialise fermented traditional cereal beverages bioburden microbial cultures are required. This investigation aimed to evaluate the physicochemical, nutritional, and sensory characteristics of NACB produced using pure cultures of Leuconostoc mesenteroides and Pediococcus pentosaceus. Pearl millet extract (PME) pasteurised at 85 °C for 15 min and cooled to 40 °C was inoculated with Leuconostoc mesenteroides and Pediococcus pentosaceus at 0.050% and 0.025% (1:0.5), respectively, and fermented at 37 °C for 18 h, referred to as plain non-alcoholic pearl millet beverage (PNAPMB). Moringa supplemented non-alcoholic pearl millet beverage (MSNAPMB) was produced following the same method as PNAPMB but a 4% moringa leaf extract powder was added before hydration of the pearl millet powder. The traditional non-alcoholic pearl millet beverage (TNAPMB) was prepared by mixing water and pearl millet flour (1:1.25; PMF:Water) and hydrated for 3 h at 25 °C. The mixture was divided into ¼ slurry which was mixed with sprouted rice flour (SRF) and ¾ portion that was gelatinised with 1 L of boiling water and cooled to 40 °C. The two portions were mixed and fermented at 37 °C for 18 h, followed by sieving, dilution with water (1:0.5, filtrate:water), and pasteurization for 15 min at 85 °C. The growth of lactic acid bacteria, pH, total titratable acidity (TTA), and sugar in PNAPMB and MSNAPMB were determined at 3 h intervals during fermentation. The final beverages were also analysed for proximate, colour and metabolites. The lactic acid bacteria were significantly (p < 0.05) affected by the fermentation period and increased from 3.32 to 7.97 log CFU/mL (pH 4.14) and 3.58 to 8.38 log CFU/mL (pH 3.65) for PNAPMB and MSNAPMB, respectively. The total titratable acidity significantly (p < 0.05) increased from 0.14 to 0.22% and from 0.17 to 0.38% in PNAPMB and MSNAPMB, respectively. The protein, total fat, moisture total sugar, and carbohydrates differed significantly (p < 0.05) among the samples. PNAPMB was preferred by a consumer panel followed by MSNAPMB and TNAPMB. Volatile compounds with beneficial anti-inflammatory and anti-pathogenic properties were identified in the beverages. Innovative fermentation of pearl millet extract using purified bioburden cultures was possible and the added Moringa oleifera leaf powder improved the nutritional quality of the resulting beverage.

The Utilisation of Acrylamide by Selected Microorganisms Used for Fermentation of Food

Acrylamide (AA) present in food is considered a harmful compound for humans, but it exerts an impact on microorganisms too. The aim of this study was to evaluate the impact of acrylamide (at conc. 0–10 µg/mL) on the growth of bacteria (Leuconostoc mesenteroides, Lactobacillus acidophilus LA-5) and yeasts (Saccharomyces cerevisiae, Kluyveromyces lactis var. lactis), which are used for food fermentation. Moreover, we decided to verify whether these microorganisms could utilise acrylamide as a nutritional compound. Our results proved that acrylamide can stimulate the growth of L. acidophilus and K. lactis. We have, to the best of our knowledge, reported for the first time that the probiotic strain of bacteria L. acidophilus LA-5 is able to utilise acrylamide as a source of carbon and nitrogen if they lack them in the environment. This is probably due to acrylamide degradation by amidases. The conducted response surface methodology indicated that pH as well as incubation time and temperature significantly influenced the amount of ammonia released from acrylamide by the bacteria. In conclusion, our studies suggest that some strains of bacteria present in milk fermented products can exert additional beneficial impact by diminishing the acrylamide concentration and hence helping to prevent against its harmful impact on the human body and other members of intestinal microbiota.