Legumes and Legume-Based Beverages Fermented with Lactic Acid Bacteria as a Potential Carrier of Probiotics and Prebiotics

Fermentation is widely used in the processing of dairy, meat, and plant products. Due to the growing popularity of plant diets and the health benefits of consuming fermented products, there has been growing interest in the fermentation of plant products and the selection of microorganisms suitable for this process. The review provides a brief overview of lactic acid bacteria (LAB) and their use in fermentation of legumes and legume-based beverages. Its scope also extends to prebiotic ingredients present in legumes and legume-based beverages that can support the growth of LAB. Legumes are a suitable matrix for the production of plant-based beverages, which are the most popular products among dairy alternatives. Legumes and legume-based beverages have been successfully fermented with LAB. Legumes are a natural source of ingredients with prebiotic properties, including oligosaccharides, resistant starch, polyphenols, and isoflavones. These compounds provide a broad range of important physiological benefits, including anti-inflammatory and immune regulation, as well as anti-cancer properties and metabolic regulation. The properties of legumes make it possible to use them to create synbiotic food, which is a source of probiotics and prebiotics.

Microbial plankton community structure and function responses to vitamin B12 and B1 amendments in an upwelling system

B vitamins are essential cofactors for practically all living organisms on Earth that are produced by a selection of microorganisms. An imbalance between high demand and limited production, in concert with abiotic processes, may explain the low availability of these vitamins in marine systems. Natural microbial communities from surface shelf water in the productive area off NW Spain were enclosed in mesocosms in winter, spring and summer 2016. In order to explore the impact of B-vitamin availability on microbial community composition (16S and 18S rRNA gene sequence analysis) and bacterial function (metatranscriptomics analysis) in different seasons, enrichment experiments were conducted with seawater from the mesocosms. Our findings revealed that significant increases in phytoplankton or prokaryote biomass associated with B12 and/or B1 amendments were not accompanied by significant changes in community composition, suggesting that most of the microbial taxa benefited from the external B-vitamin supply. Metatranscriptome analysis suggested that many bacteria were potential consumers of B12 and B1 vitamins, although the relative abundance of reads related to synthesis was ca. 3.6-fold higher than that related to uptake. Alteromonadales and Oceanospirillales accounted for important portions of B1 and B12 vitamin synthesis gene transcription, despite accounting for only minor portions of the bacterial community. Flavobacteriales appeared to be mostly involved in B12 and B1 vitamin uptake and Pelagibacterales expressed genes involved in B1 vitamin uptake. Interestingly, the relative expression of B12 and B1 vitamin synthesis genes among bacteria strongly increased upon inorganic nutrient amendments. Collectively, these findings suggest that upwelling events intermittently occurring during spring and summer in productive ecosystems may ensure an adequate production of these cofactors to sustain high levels of phytoplankton growth and biomass. Importance Section B-vitamins are essential growth factors for practically all living organisms on Earth that are produced by a selection of microorganisms. An imbalance between high-demand and limited-production may explain the low concentration of these compounds in marine systems. In order to explore the impact of B-vitamin availability on bacteria and algae in the coastal waters off NW Spain, six experiments were conducted with natural surface water enclosed in winter, spring and summer. Our findings revealed that increases in phytoplankton or bacteria growth associated with B12 and/or B1 amendments were not accompanied by significant changes in community composition, suggesting that most microorganisms benefited from the B-vitamin supply. Our analyses confirmed the role of many bacteria as consumers of B12 and B1 vitamins, although the relative abundance of genes related to synthesis was ca. 3.6-fold higher than that related to uptake.Interestingly, prokaryote expression of B12 and B1-synthesis genes strongly increased when inorganic nutrient were added. Collectively, these findings suggest that upwelling of cold and nutrient-rich waters occurring during spring and summer in this cooastal area may ensure an adequate production of B vitamins to sustain high levels of algae growth and biomass.

Selection of microorganisms and preparation of inoculants with potential applications in the remediation of soil contaminated with hexazinone

ABSTRACT: The excessive use of agrochemicals negatively impacts the environment, making the development of sustainable technologies for the reduction of contaminants in soil necessary. Hexazinone is the herbicide most used for sugarcane crops and persists in the environment. Moreover, its main route of degradation in the soil is through microorganisms. Therefore, six microorganisms were selected that presented growth in the presence of the herbicide; SCR1 - Microbacterium arborescens; SCR2 - Bacillus pumilus; SCM3 - Stenotrophomonas maltophilia; SCM4 - Bacillus cereus; SCM5A - M. arborescens; and SCM5B - B. safensis. A test was performed to evaluate the ability of each lineage in phosphate solubilization. For the Ca3(PO4)2 solubilization test, the strains that showed the best results were B. pumilus and S. maltophilia. Subsequently, the inoculants were prepared and the concentrations after plating were 2.71 × 109 CFU mL-1 for B. pumilus, 1.02 × 109 CFU mL-1 for S. maltophilia, and 1.14 × 1010 CFU mL-1 for a combination of the two strains. These were satisfactory values for use as inoculants.

Optimal Criteria for the Selection of Probiotics, Based on their Mode of Action

The objective of this review was to discuss some of the criteria which influence the selection of microorganisms with probiotic properties based on their mode of action. The most common bacteria that belong to the “group” probiotics are the Lactobacillus and Bifidobacterium species/strains. Probiotics have benefits and effects by their mechanism of action in different axial locations such as: producing substances, influencing immune function and response, modification as well as maintenance of a healthy population of microorganisms in the intestinal environment. Probiotics have demonstrated significant potential as therapeutic options for a variety of diseases Potential peripheral pathways that link probiotic ingestion in the brain function are focused on the role of the vagal afferent nerve signalling and changes in the cerebral levels of neuromodulators. The application of probiotic microorganisms represents a way to effectively influence the composition of the intestinal microbiome and the immune system of the host, as well as they can be considered as a suitable alternative to influence a healthy quality of life.

Isolation and selection of microorganisms in cocoa fermentation

The objectives of this study were to investigate the change of microorganisms involved in cocoa (Theobroma cacao) fermentation and then to isolate, characterize and select the important microorganisms in cocoa fermentation. The results showed that microbial quantities continuously changed during cocoa fermentation and the highest quantity of dominant microorganisms at different stages of fermentation process as 8.03 log cfu/g of yeast, 6.34 log cfu/g of mold, 7.77 log cfu/g of lactic acid bacteria, 7.87 log cfu/g of acetic acid bacteria, 7.25 log cfu/g of Bacillus, and 10.93 log cfu/g of the total aerobic bacteria. There were nine yeast isolates belonging 5 genera of Saccharomyces, Kluyveromyces, Brettanomyces, Candida and Cystofilobasidium; 9 mould isolates belonging to 2 genera of Rhizopus and Aspergillus; 11 acetic acid bacteria isolates belonging to Acetobacter; and 13 spore-forming bacterial isolates belonging to Bacillus isolates. Three isolates of yeast (CY-1a, CY-1b, CY-2a) belonging to Kluyveromyces possessed the high fermentative capacity and 4 Acetobacter isolates (CAAB-1d, CAAB-1a, CAAB-1e and CAAB-2d) produced high amounts of acetic acid.

The use of various species of fungi in biofiltration of air contaminated with odorous volatile organic compounds

Air pollution with odorous compounds is a significant social and environmental problem. This paper presents biological deodorization methods. The attention is focused on the application of biotrickling filters for air deodorization. Principles of their operation are discussed, indicating the key role of the selection of microorganisms responsible for the degradation of odorous compounds. A literature overview of the used fungal species is presented and the advantages of using fungi in comparison with bacteria are indicated. The results of experimental studies on the n-butanol removal in biotrickling filter are presented.