Effects of fermentation with Lactobacillus fermentum 21828 on the nutritional characteristics and antioxidant activity of Lentinus edodes liquid

Lactic acid bacterial fermentation as a biotransformation strategy to enhance the bioavailability of phenolic antioxidants in fruits and vegetables: A comprehensive review

Fruits and vegetables (FVs) are rich sources of macro and micro-nutrients crucial for a healthy diet. In addition to these nutrients, FVs also contain fibre and phytochemicals known for their antioxidant properties. Despite the growing evidence of the disease-preventive role of antioxidants in FVs, their bioavailability and bioaccessibility vary significantly and have not been adequately explored. Lactic acid bacterial (LAB) fermentation is considered the most appropriate and accessible biotechnological approach to maintain and enhance the safety, nutritional, sensory and shelf-life properties of perishable foods such as FVs. This review critically assesses how LAB fermentation could be utilised as a promising biotransformation strategy to enhance the bioavailability of antioxidants in FVs. Furthermore, it discusses the potential use of uniquely nutritious Australian native fruits as suitable candidates for LAB fermentation. Further research is essential to identify the beneficial properties of bioactive compounds and effective LAB-based biotransformation strategies to improve the bioavailability and bioaccessibility of antioxidants in FVs.

Lactic acid bacteria sequential fermentation improves viable counts and quality of fermented apple juice via generating two logarithmic phases

This study investigated the impact of lactic acid bacteria (LAB) sequential fermentation on viable counts and apple juice quality. The optimal fermentation conditions were obtained by a step-by-step optimization process, including pH 4.5, temperature 37 °C, the second inoculation time 16 h, total fermentation time 40 h and fermentation sequence (first 21,805 + 21,828, second 20,241). Under the optimal conditions, sequential fermentation allowed LAB to experience two logarithmic phases, increasing viable counts to 1.38 × 108 CFU/mL, exceeding simultaneous fermentation for 24 h and 40 h by 4.10 × 107 CFU/mL and 5.40 × 107 CFU/mL, respectively. This process enhanced sugar utilization, yielding more lactic acid and polyphenols. Furthermore, sequential fermentation improved DPPH (71.71 %) and ABTS (84.79 %) scavenging rates, and enriched volatile compounds, particularly beta-Damascenone, potentially contributing to floral and richer apple flavor. Sequential fermentation also achieved optimal sensory acceptability. This study proposes a novel strategy for high-density LAB fermentation to produce high-quality apple juice.

Effect of microwave-puffed on Auricularia auricula polysaccharide and probiotic fermentation on its biotransformation and quality characteristics during storage period

In this study, probiotics with superior fermentation performance were screened, and the mixed-bacteria fermentation was carried out with Auricularia auricula treated with microwave-puffed process as fermentation substrate, and the changes in nutritional quality under different storage conditions were investigated. The results showed that the acid and bile salt resistance of Lactiplantibacillus plantarum 21,801 and 21,805 reached 95 % and 75 % respectively, and the intestinal adhesion was superior; microwave puffing treatment had the highest retention rate of A. auricula polysaccharides and the lowest loss of polyphenols, and no effect on soluble protein. Mixed bacterial fermentation significantly increased the total polyphenols and total flavonoids of A. auricula (p < 0.05), and the DPPH and ABTS radical scavenging reached 48.31 % and 73.21 % respectively. Furthermore, the viable counts, DPPH radical scavenging, color, and sensory quality of fermented A. auricula remained stable when stored at 4 °C. In contrast, when stored at 25 °C for 7 days, the taste was unfavorable, undesirable odor and spoilage occurred; by 21 days, DPPH clearance rate dropped below 40 % and color changed significantly (△E > 2). In conclusion, the probiotic mixed fermentation and storage conditions had a significant effect on the biometabolic transformation of macromolecules and other substances in A. auricula.

A concise review of the nutritional profiles, microbial dynamics, and health impacts of fermented mushrooms

Mushrooms have garnered significant attention for their nutritional composition and potential health benefits, including antioxidant, antihypertensive, and cholesterol-lowering properties. This review explores the nutritional composition of edible mushrooms, including their high protein content, essential amino acids, low fat, cholesterol levels, and bioactive compounds with medicinal value. Moreover, the study analyzes the microbiology of mushroom fermentation, focusing on the diverse microbial ecosystem involved in the transformation of raw mushrooms and the preservation methods employed to extend their shelf life. Special emphasis is placed on lactic acid fermentation as a cost-effective and efficient preservation technique. It involves controlling the growth of lactic acid bacteria to enhance the microbial stability and nutritional quality of mushrooms. Furthermore, the bioactivities of fermented mushrooms are elucidated, which are antioxidant, antimicrobial, anticancer, anti-glycemic, immune modulatory, and other biological activities. The mechanisms underlying these bioactivities are explored, emphasizing the role of fermented mushrooms in suppressing free radicals, enhancing antioxidant defenses, and modulating immune responses. Overall, this review provides comprehensive insights into the nutritional composition, microbiology, bioactivities, and underlying mechanisms of fermented mushrooms, highlighting their potential as functional foods with significant health-promoting properties.

Investigation the nutritional properties of Auricularia auricula pulp fermented with Lactobacillus strains and their effects on gut microbiota

BACKGROUND

Auricularia auricula is rich in bioactive components, and microbial fermentation can further dramatically increase its content and bioavailability. However, there are few studies on the relationship between fermented A. auricula pulp (FAAP) and gut microbiota. In this study, standard strains Lactobacillus plantarum 21801 and 21805 purchased from the China Center of Industrial Culture Collection were used to ferment A. auricula pulp at a ratio of 2:1, with an inoculum of 5%, a fermentation temperature of 31 °C, and a fermentation time of 22 h. The nutritional properties, aroma, and color of FAAP and their effects on the body characteristics of mice and the structure and abundance of gut microbiota are discussed.

RESULTS

The results showed that, compared with A. auricula pulp, FAAP significantly increased the nutritional properties while maintaining favorable sensory quality and flavor profiles. Among them, the content of total polyphenols and total flavonoids reached 22.04 μg mL-1 and 20.56 μg mL-1 respectively, and the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid free-radical scavenging rate increased to 73.21%. The consumption of FAAP had no negative effects on weight or liver and kidney function in mice and dramatically enhanced the antioxidant capacity in the liver and serum. The production of short-chain fatty acids in the gut was promoted, the relative abundance of beneficial bacteria (Lactobacillus, Bifidobacterium, norank_f__Muribaculaceae and unclassified_f__Lachnospiraceae) increased, and the growth of some pathogenic bacteria (Helicobacter, Mucispirillum, and Alloprevotella) was inhibited.

CONCLUSION

These findings demonstrate that FAAP is rich in nutrients and has unique functional properties that promote host health and regulate the gut microbiota. © 2023 Society of Chemical Industry.

Development of a polyphenol-enriched whole kiwifruit dietary supplement and its potential in ameliorating hyperlipidemia

BACKGROUND

Kiwifruit pomace, which contains abundant phenolic compounds, is typically discarded during the juicing process, leading to wastage of valuable resources. To address this issue, various indicators (including total acidity, sugar/acid ratio, vitamin C, total polyphenols, polyphenol monomers, and soluble solids content) of 15 kiwifruit cultivars were evaluated and juiced. Then, a polyphenol-concentrated solution from kiwifruit pomace was backfilled into kiwi juice to prepare whole nutritious compound kiwi juice, and its anti-hyperlipidemic activity on obese model mice was then investigated.

RESULTS

Through grey relational analysis and the technique for order preference by similarity to an ideal solution (TOPSIS), Kuimi and Huayou were identified as the predominant varieties for juicing, with weighted relevance scores of 0.695 and 0.871 respectively and TOPSIS scores of 0.6509 and 0.8220 respectively. The polyphenol content of Cuixiang pomace was 43.97 mg g-1 , making it the most suitable choice for polyphenol extraction. By backfilling a polyphenol-concentrated solution derived from Cuixiang pomace into compound kiwi juice of Huayou and Kuimi, the whole nutritious compound kiwi juice with polyphenols was produced and exhibited superior bioactivities, including enhanced hepatic oxidative stress defense, and alleviated serum lipid abnormalities. Furthermore, whole nutritious compound kiwi juice with polyphenols ameliorated host intestinal microbiota dysbiosis by increasing the relative abundance of the phyla Bacteroidota and Verrucomicrobiota.

CONCLUSION

A hypolipidemic dietary supplement based on kiwifruit pomace polyphenols has been successfully developed, providing an effective solution for hyperlipidemia intervention. © 2023 Society of Chemical Industry.

Physicochemical, sensory, and antioxidant characteristics of stirred-type yogurt enriched with Lentinula edodes stipe powder

The Lentinula edodes stipe (LES), a by-product of L. edodes fruiting body processing, is rich in dietary fiber, protein, and polysaccharides, which can be served as the functional ingredient in dairy products. In this study, stirred yogurts fortified with 1%, 2%, and 3% LES were prepared, and the effects of LES on the changes in color, pH, titratable acidity (TA), viable lactic acid bacteria (LAB) cells, syneresis, viscosity, texture, and antioxidant activity of the flavored yogurt were monitored at the beginning and the end of storage. The LES decreased the lightness, increased the red-green color values and yellow-blue color values, decreased the pH values, and increased the contents of TA, the viable LAB cells, and the antioxidant activity of yogurt samples in a dose-dependent manner. The addition of LES showed double-edged effects on the texture of yogurt, which significantly reduced firmness and viscosity but decreased the syneresis. Compared with plain yogurt, the 2% LES-fortified yogurt exhibited similar index values of texture parameters and higher scores of the appearance, fermented odor, taste quality, and overall acceptance, suggesting that this might be the optimal dose for industrial production. After cold storage for 28 days, pH values of all yogurt samples further decreased with increasing of TA. Interestingly, syneresis of LES-fortified yogurt decreased and the viable LAB cells and antioxidant activity of 3% LES-fortified yogurt slightly decreased. Therefore, LES is beneficial to improve physicochemical, sensory, and antioxidant properties of yogurt, which has the potential to be used in functional dairy products.