Studies on the development of non-dairy probiotic foods and beverages are emerging. The optimal Lactobacillus and carbon resources were screened to improve the viability of probiotics in blueberry ...pomace. During fermentation, the total titratable acid and the viable counts were measured and peaked at 24 h, 15.75 mM and 11.59 Log CFU mL−1 respectively. Lactic acid content increased from 2.361 mg mL−1 to 6.334 mg mL−1, while citric acid content was decreased significantly. Additionally, the antioxidant activity was improved, which may be attributed to the increase of total phenols and flavonoids up to 4629.21 μg GAE mL−1 and 404.99 μg RE mL−1. Simulated gastrointestinal digestion in vitro showed that the total polyphenols were decreased slightly, while anthocyanins were increased. We also studied the cholesterol-lowing capability of fermented BPL and found that the cholesterol-clearance rate could reach 67.17%. Moreover, through mice weight-loaded swimming experiments, we observed that the physical strength of mice fed a fermented juice for one month was significantly better than that of the control group (p < 0.05). Therefore, this study provides a high value application of blueberry pomace and the fermented blueberry pomace with probiotics as a new type of probiotic food can furnish potentially value to human health.
Display omitted
•Mixed fermented blueberry pomace by probiotics improves the content of the total phenols, flavonoids and inoxidizability.•Fermented blueberry pomace has certain effect on cholesterol clearance.•Fermented blueberry pomace shows great influence on anti-fatigue capability on weight-loaded swimming in mice.
Sukmawati S, Ratna R, Sipriyadi, Yunita M. 2023. Characterization and molecular identification of bacteria from mackerel bekasam in Sorong City, Southwest Papua Province, Indonesia. Biodiversitas 24: ...4967-4977. Bekasam is traditional food type produced by traditional fermented fish. Microbes that grow through fermentation play an important role in forming the product’s aroma, texture, and overall quality. The study aimed to determine the biochemical characteristic of bacteria from mackerel (Scomberomorus sp.) bekasam in Sorong City and identify bacteria at the molecular level. This research was a descriptive study, which described the results of the characterization of bacteria from fermented mackerel fish and the results of molecular identification to the species level through the PCR (Polymerase Chain Reaction) technique. Then, the DNA sequences were further analyzed using the agarose gel electrophoretic separation method to visualize the bacterial DNA profile. The biochemical characterization of bacterial isolates from mackerel showed that all isolates were negative indole, and eight isolates were positive in reducing nitrate. In comparison, four isolates were negative in reducing nitrate, then all isolates had proteolytic activity except the FST 3.1 and FST 3.2 isolates. Eleven isolates were positive in hydrolyzing fat, and one isolate could not hydrolyze fat. According to the DNA patterns seen in electrophoresis and alignment of the 16 sRNA gene sequences, several types of bacteria had been identified as Bacillus paramycoides strain 2883 FST 1.1, Bacillus paramycoides strain 3665 FST 2.1, Bacillus mobilis strain ICA-144 FST 3.1, Bacillus cereus strain ATCC 14579 FNT 1.1, Bacillus mobilis strain ICA-144 FNT 2.1, and Bacillus cereus strain ATCC 14579 FNT 3.1.
In the present study, we aimed to evaluate the single or conjoint effects of Lactococcus lactis (L. lactis) L19 and Enterococcus faecalis (E. faecalis) W24 isolated from the intestine of Channa argus ...(C. argus) on digestive enzyme activity, antioxidant capacity, intestinal microbiota and morphology of C. argus (initial weight, 9.50 ± 0.03 g). The fish were fed for 56 days with a basal diet (CK) or diets supplemented with 1.0 × 108 CFU/g of L. lactis (L19), E. faecalis (W24), L. lactis + E. faecalis (L + W). Results indicated that these three lactic acid bacteria (LAB) supplementary diets especially the L19 produced significant improvement in the digestive enzyme activity (protease, amylase and lipase) in liver, stomach and intestine compared with control (P < .05). LAB supplementations were enhanced the liver and intestine antioxidant status (SOD, CAT, GSH-Px, T-AOC and MDA) in comparison to the control (P < .05). Serum biochemical parameters (ALT and AST) of fish fed with LAB supplemented diets showed significantly decreased compared with control (P < .05). The intestinal morphology showed protection in fish fed both L19 or/and W24. High-throughput sequencing revealed L19 supplementation can effectively increase the generation of probiotic bacteria and decrease the abundance of aquatic pathogens. Therefore, supplementation of L. lactis L19 showed more effective protection than E. faecalis W24 or the mixture of the two for promoting digestive enzyme activity, antioxidant capacity, intestinal microbiota and morphology of C. argus.
•The digestive enzyme activity were enhanced in fish fed both L19 or/and W24.•The antioxidant capacity were enhanced in fish fed both L19 or/and W24.•The liver health and intestine morphology were protected in both L19 or/and W24.•L19-supplemental diets can regulate the intestine microbiota of Channa argus.
The increasing concern of consumers about food quality and safety and their rejection of chemical additives has promoted the breakthrough of the biopreservation field and the development of studies ...on the use of beneficial bacteria and their metabolites as potential natural antimicrobials for shelf life extension and enhanced food safety. Control of foodborne pathogens in meat and meat products represents a serious challenge for the food industry which can be addressed through the intelligent use of bio-compounds or biopreservatives. This article aims to systematically review the available knowledge about biological strategies based on the use of lactic acid bacteria to control the proliferation of undesirable microorganisms in different meat products. The outcome of the literature search evidenced the potential of several strains of lactic acid bacteria and their purified or semi-purified antimicrobial metabolites as biopreservatives in meat products for achieving longer shelf life or inhibiting spoilage and pathogenic bacteria, especially when combined with other technologies to achieve a synergistic effect.
Lactococcus phages that belong to the genus Ceduovirus are among the three most frequently isolated phage groups infecting Lactococcus lactis starter strains in dairy plants. In this study, we ...characterized virulent Lactococcus phage BIM BV-114 isolated from industrial cheese brine in Belarus and identified as Ceduovirus. The bacteriophage demonstrated a relatively short lytic cycle (latent period of 23 ± 5 min, lysis time of 90 ± 5 min), high thermal stability (inactivation after 7 min at 95 °C in skimmed milk) and tolerance to UV radiation (inactivation time – 15 min), indicating adaptation for better persistence in dairy facilities. The genome of the phage BIM BV-114 (21 499 bp; 37 putative open reading frames) has a similar organization to that of other Ceduovirus phages. RLf1_00140 and RLf_00050 gene products, found in the early genes region, may be involved in the sensitivity of phage to the lactococcal abortive infection mechanisms AbiV and AbiQ, respectively. Furthermore, nucleotide deletion, observed in the middle region of the gene encoding putative tape measure protein (RLf1_00300), is possibly responsible for increased thermal tolerance of phage BIM BV-114. Together, these findings will contribute to a better knowledge of virulent Lactococcus phages and the development of effective methods of their control for dairy technologies.
Low-intensity pulsed electric fields (PEF) were applied to a starter culture mix (Streptococcus thermophilus, Lactobacillus bulgaricus, and partially skimmed milk) before the fermentation stage of ...natural yogurt. The impact of PEF processing conditions on yogurt fermentation time and quality characteristics was evaluated. PEF parameters were set based on a factorial experimental design; independent variables: electric field strength, pulse-frequency, and pulse-width, were explored, having fermentation time as a response. Most PEF treatments reduced fermentation time by 0.31–0.52 h compared to conventional yogurt processing (CY) (4.70 ± 0.23 h). The shortest time (4.18 ± 0.04 h) resulted from PEF pre-treatment with 8-μs monopolar pulses at 1 kV/cm and 150 Hz during 400 μs. The physicochemical and sensory characteristics of PEF-treated yogurt were similar to those of the CY immediately after processing and during refrigeration storage. Low-intensity PEF could be a promising alternative pre-treatment of yogurt production, reducing fermentation time while maintaining quality attributes of natural yogurt.
Conventional yogurt processing lasts around 4.5–6 h, representing high energy consumption and production costs. The application of pulsed electric fields (PEF) processing to the starter culture before yogurt fermentation represents a potential alternative to diminish production time by stimulating lactic acid bacteria and accelerating fermentation stage. This study demonstrated that low-intensity PEF (1–3 kV/ cm) reduced fermentation time by 0.31–0.52 h without compromising yogurt's quality properties, including physicochemical characteristics and sensory attributes. Obtained results suggest that this technology allows more efficient and sustainable yogurt production methods, positively impacting industry and consumers.
•Low intensity PEF (1–3 kV/ cm) reduced yogurt fermentation time by 0.31–0.52 h.•PEF could stimulate LAB metabolism, increasing yogurt LA concentration 0.76–0.90%.•PEF treatment did not affect yogurts flavor, color, titrable acidity and viscosity.
Consumer interest in healthy lifestyle and health-promoting natural products is a major driving force for the increasing global demand of biofunctional dairy foods. A number of commercial sources ...sell synthetic formulations of bioactive substances for use as dietary supplements. However, the bioactive-enrichment of health-oriented foods by naturally occurring microorganisms during dairy fermentation is in increased demand. While participating in milk fermentation, lactic acid bacteria can be exploited
as microbial sources for naturally enriching dairy products with a broad range of bioactive components that may cover different health aspects. Several of these bioactive metabolites are industrially and economically important, as they are claimed to exert diverse health-promoting activities on the consumer, such as anti-hypertensive, anti-inflammatory, and anti-diabetic, anti-oxidative, immune-modulatory, anti-cholesterolemic, or microbiome modulation. This review aims at discussing the potential of these health-supporting bacteria as starter or adjunct cultures for the elaboration of dairy foods with a broad spectrum of new functional properties and added value.
Display omitted
•LABs (Weissella, Lactobacillus, and Pediococcus) were dominant bacteria around day 2.•Thermotolerant/thermophilic taxa exhibited the highest proportion after day 6.•A metabolic ...network of core microbes involved in flavor development was constructed.•Potential populations responsible for the production of lytic enzymes were revealed.•Lactic acid and bio-heat produced by microbes could promote the microbiota shift.
As a widely used Asian starter culture, the quality of daqu can significantly affect the organoleptic characteristics of the final products, yet the microbial metabolic network involved in flavor development remains unclear. This study aims to investigate that network based on the dynamics of physicochemical properties, microbial community, and volatile compounds in medium-temperature daqu (MT-daqu) during spontaneous fermentation. Analyses using the metagenomic data set facilitated the gene repertoire overview of this ecosystem, indicating that Lactobacillales (mainly Weissella, Lactobacillus, and Pediococcus), Mucorales (mainly Lichtheimia), and Eurotiales (mainly Aspergillus, Rasamsonia and Byssochlamys) were the potential predominant populations successively responsible for the production of lytic enzymes and flavor precursors/compounds in MT-daqu. Flavor-relevant pathways were found to exist in multiple species, but only bacteria showed the potential to participate in butane-2,3-diol (e.g. Weissella, Lactobacillus, and Staphylococcus) and butanoate (Thermoactinomyces) metabolism, and only fungi were potentially involved in biosynthesis of guaiacol (Byssochlamys) and 4-vinylguaiacol (Aspergillus). Furthermore, a combined analysis revealed that the acidic thermal environment present in early phases was mainly due to the catabolic activities of Lactobacillales and Lichtheimia, which could contribute to the effective self-domestication of microbiota. The study helps elucidate the different metabolic roles of microorganisms and disclose the formation mechanism of daqu’s partial functions, namely providing various aromatic substances/precursors and enzymes.
Lactic acid is an industrially important product with a large and rapidly expanding market due to its attractive and valuable multi-function properties. The economics of lactic acid production by ...fermentation is dependent on many factors, of which the cost of the raw materials is very significant. It is very expensive when sugars, e.g., glucose, sucrose, starch, etc., are used as the feedstock for lactic acid production. Therefore, lignocellulosic biomass is a promising feedstock for lactic acid production considering its great availability, sustainability, and low cost compared to refined sugars. Despite these advantages, the commercial use of lignocellulose for lactic acid production is still problematic. This review describes the “conventional” processes for producing lactic acid from lignocellulosic materials with lactic acid bacteria. These processes include: pretreatment of the biomass, enzyme hydrolysis to obtain fermentable sugars, fermentation technologies, and separation and purification of lactic acid. In addition, the difficulties associated with using this biomass for lactic acid production are especially introduced and several key properties that should be targeted for low-cost and advanced fermentation processes are pointed out. We also discuss the metabolism of lignocellulose-derived sugars by lactic acid bacteria.
PDF
