Effect of lactobacillus strains on phenolic profile, color attributes and antioxidant activities of lactic-acid-fermented mulberry juice

Effects of probiotic litchi juice on immunomodulatory function and gut microbiota in mice

Development new functional foods containing probiotics had gained much attention during the past two decades. In this study, probiotic litchi juice was developed, and its effects on immunomodulatory function and gut microbiota were evaluated. Firstly, the litchi juice was fermented with Lactobacillus casei, which increased total phenolic, total flavone, and exopolysaccharide contents of the litchi juice. Hence, the immunomodulatory influence of fermented litchi juice (FL) was investigated in cyclophosphamide-induced mice. The results showed that FL enhanced immune organs indexes (spleen, thymus) and antioxidant capacity, improved the secretions of cytokines (IL-2, IL-6) and immunoglobulins (IgA, IgG, SIgA), and protected the intestinal tract. Finally, the effect of FL on gut microbiota was analyzed by high-throughput sequencing analysis. The changes in the relative abundance of dominant microbe were investigated at phylum and genus levels, respectively. After treatment with FL, the relative abundance of Firmicutes phylum was dramatically increased, as well as the genera of Faecalibaculum, Lactobacillus, and Akkermansia. These findings indicated that probiotic litchi juice could alleviate immune dysfunction and modify gut microbiota structure of mice, which provide a potential functional food to improve the host health.

Biotransformation of phenolics and metabolites and the change in antioxidant activity in kiwifruit induced by Lactobacillus plantarum fermentation

BACKGROUND

Changes in antioxidant activity of fruit during fermentation are related to changes in the composition of phenolic acids and flavonoids. In this study, we investigated the effects of Lactobacillus plantarum on the phenolic profile, antioxidant activities, and metabolites of kiwifruit pulp.

RESULTS

Lactobacillus plantarum fermentation increased scavenging activity of 1-diphenyl-2-picrylhydrazyl (DPPH) and 2,20-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) radicals. The content of phenolics and flavonoids was increased after fermentation. Correlation analysis demonstrated that the phenolic and flavonoid content was responsible for increasing the scavenging activities of DPPH and ABTS. Lactobacillus plantarum influenced the phenolic profile of the pulp. Protocatechuic and chlorogenic acids were the predominant phenolic acids in fermented kiwifruit pulp. Gallic acid, chlorogenic acid, epicatechin, and catechins were degraded by L. plantarum. The content of 6,7-dihydroxy coumarin and p-coumaric acid, and especially protocatechuic acid, was increased by fermentation. Metabolic differences in lactic acid, fructose, phosphoric acid, gluconolactone, and sugar were evident between non-fermented and fermented kiwifruit.

CONCLUSION

Lactobacillus plantarum fermentation increased antioxidant compounds and antioxidant activity in kiwifruit pulp. These results provide the foundation to target the functional benefits of L. plantarum-fermented kiwifruit pulp for further human, animal, and plant health applications. © 2020 Society of Chemical Industry.

Preventive Effect of Fermented Chestnut Inner Shell Extract on Obesity-Induced Hepatic Steatosis

This study aimed to investigate the effects of the gallic acid-enriched fermented chestnut inner shell extract (FCCE) by Saccharomyces cerevisiae on a high fat diet (HFD)-induced obesity and hepatic steatosis in vivo mouse model. Mice feeding FCCE exhibited reduced body weight gain compared to those in the HFD-fed group, and showed lower abdominal fat pad weight including epididymal, retroperitoneal, and mesenteric adipose tissue. Further, FCCE administration decreased adipocyte size by suppressing adipogenic factors such as peroxisome proliferator activated receptor γ and CCAAT/ enhancer-binding protein α, and lipogenic factors such as sterol regulatory element-binding protein-1c, fatty acid synthase, and stearoyl CoA desaturase-1. Moreover, FCCE decreased levels of lipids in serum and liver as well as serum alanine aminotransferase and aspartate aminotransferase levels, markers of liver injury. Histological observations of the liver showed that FCCE significantly attenuated HFD-induced hepatic steatosis. The effect of FCCE on hepatic lipid regulatory factors may be partly associated with adenosine monophosphate-activated protein kinase activation. These results suggest that gallic acid-enriched FCCE has potential to be a promising functional food for prevention of obesity and obesity-related fatty liver disease.

Microbiological, Biochemical, and Functional Aspects of Fermented Vegetable and Fruit Beverages

In recent years, the request for the functional beverages that promote health and wellness has increased. In fact, fermented juices are an excellent delivering means for bioactive components. Their production is of crucial importance to supply probiotics, in particular, for people with particulars needs like dairy-product allergic consumers and vegetarians. This review focuses on recent findings regarding the microbial composition and the health benefits of fermented fruit and vegetable beverages by lactic acid bacteria, kefir grains, and SCOBY as well as discussing the metabolites resulting from these fermentations process. Moreover, limits that could restrain their production at the industrial level and solutions that have been proposed to overcome these constraints are also reviewed.

Spontaneously fermented curly kale juice: Microbiological quality, nutritional composition, antioxidant, and antimicrobial properties

Nondairy fermented products, such as fruit and vegetable juices, are gaining popularity among consumers worldwide for health-related and economic reasons. The purpose of this study was to determine the changes in microbiological quality; antimicrobial and antioxidant activity; and phenolic, vitamin C, minerals, and cadmium content occurring during spontaneous fermentation of curly kale juice. The fermentation process contributed to a significant growth of lactic acid bacteria, enterococci, and yeasts, while no pathogens of Escherichia coli and Salmonella spp. were observed. The antimicrobial properties of the obtained juice improved during fermentation for all indicator microorganisms. Total phenolic content and antioxidant activity increased from 48 to 116 mg gallic acid equivalent/100 mL and from 4.5 to 6.8 mM Trolox/100 mL, respectively, while the content of vitamin C decreased. The results indicated that 100 mL of juice provided a significant contribution to the recommended mineral intake. Moreover, the content of heavy metal Cd was within acceptable limit (6 µg/kg). Overall, our findings indicate that fermented curly kale juice may become popular in the functional food sector, especially among vegetarians and consumers with lactose intolerance or allergy to milk proteins. PRACTICAL APPLICATION: As the market for fermented fruit and vegetable products grows, new plant materials rich in biologically active compounds are being sought. Considering the high demand for sauerkraut, the fermentation of other cruciferous vegetables seems interesting. One example is curly kale, which has been classified as "superfood" due to its numerous beneficial health properties, such as strong antioxidant activity, high vitamins, and minerals content. In addition, a market niche exists due to a lack of fermented green curly kale products on the market, making our study particularly relevant.

Lactic Fermented Fruit or Vegetable Juices: Past, Present and Future

Numerous traditional low-alcohol fermented beverages produced from fruit or vegetables are described around the world. Fruit and vegetables and lactic fermented products both present nutritional benefits, which give reasons for the recent expansion of non-dairy lactic fermented juices on the market. In addition, fruit and vegetable juices are new carriers for probiotic bacteria. Specific phenotypic traits of lactic acid bacteria (LAB) are required so that LAB can effectively grow in fruit or vegetable juices, increase their safety and improve their sensory and nutritional quality. From the diversity of microbiota of spontaneous fermentations, autochthonous starters can be selected, and their higher performance than allochthonous LAB was demonstrated. Achieving long-term storage and constant high quality of these beverages requires additional processing steps, such as heat treatment. Alternatives to conventional treatments are investigated as they can better preserve nutritional properties, extract bioactive compounds and promote the growth and metabolism of LAB. Specific processing approaches were shown to increase probiotic viability of fruit and vegetable juices. More knowledge on the metabolic activity of lactic acid bacterium consortium in fruit or vegetable juices has become a bottleneck for the understanding and the prediction of changes in bioactive compounds for functional beverages development. Hopefully, the recent developments of metabolomics and methods to describe enzymatic machinery can result in the reconstruction of fermentative pathways.

Non-Saccharomyces yeast and lactic acid bacteria in Co-inoculated fermentations with two Saccharomyces cerevisiae yeast strains: A strategy to improve the phenolic content of Syrah wine

Syrah must was co-inoculated with mixed cultures of Saccharomyces + O. oeni/Lb. plantarum and Saccharomyces + non-Saccharomyces + O. oeni/Lb. plantarum to evaluate the effect on phenolics and sensory attributes. Reference wines were produced by S. cerevisiae. Malvidin-3-O-glucoside, flavan-3-ols, flavonols and phenolic acids were quantified using a RP-HPLC technique. Physicochemical characteristics and sensory attributes were measured. Total acidity and alcohol in mixed co-inoculations were different from reference wines. The concentration of l-malic acid was 7-times less in mixed co-inoculations. Mixed co-inoculations had ca. 1.3-times more malvidin-3-O-glucoside and phenolic acids than reference wines. Flavan-3-ols and flavonols were not different between mixed co-inoculations and reference wines. Acidity and astringency were least in mixed co-inoculations. Mouthfeel and bitterness least in S. cerevisiae wines. Tasters preferred mixed co-inoculated wines. Mixed co-inoculation is a strategy to contemplate for Syrah vinification but the modalities of inoculation need further investigation. Success depends on a suitable combination of yeast/bacteria and consideration of strain variation.

Fermentation by Multiple Bacterial Strains Improves the Production of Bioactive Compounds and Antioxidant Activity of Goji Juice

Microorganisms can be used for enhancing flavors or metabolizing functional compounds. The fermented-food-derived bacterial strains comprising Bacillus velezensis, Bacillus licheniformis, and Lactobacillus reuteri mixed with Lactobacillus rhamnosus and Lactobacillus plantarum were used to ferment goji berry (Lycium barbarum L.) juice in this study. The fermentation abilities and antioxidant capacities of different mixtures of multiple strains in goji juice were compared. The results showed that the lactic acid contents increased 9.24-16.69 times from 25.30 ± 0.71 mg/100 mL in goji juice fermented using the SLV (Lactobacillus rhamnosus, Lactobacillus reuteri, and Bacillus velezensis), SZP (Lactobacillus rhamnosus, Lactobacillus plantarum, and Bacillus licheniformis), and SZVP (Lactobacillus rhamnosus, Lactobacillus plantarum, Bacillus velezensis, and Bacillus licheniformis) mixtures, and the protein contents increased 1.31-2.11 times from 39.23 ± 0.67 mg/100 mL. In addition, their contents of volatile compounds increased with positive effects on aroma in the fermented juices. Conversion of the free and bound forms of phenolic acids and flavonoids in juice was influenced by fermentation, and the antioxidant capacity improved significantly. Fermentation enhanced the contents of lactic acid, proteins, volatile compounds, and phenols. The antioxidant capacity was strongly correlated with the phenolic composition.

Effect of Lactobacillus acidophilus, Oenococcus oeni, and Lactobacillus brevis on Composition of Bog Bilberry Juice

This study investigated the impact of Lactobacillus acidophilus NCFM, Oenococcus oeni Viniflora^® Oenos and Lactobacillus brevis CICC 6239 on bog bilberry juice with a considerably low pH and rich in anthocyanins content. Moreover, the effects of the strains on the composition of phenolic compounds, amino acids, ammonium ion, biogenic amines, reduced sugars, organic acids, and color parameters of the juice were studied. All three bacteria consumed sugars and amino acids but exhibited different growth patterns. Lactic acid was detected only in L. acidophilus inoculated juice. The content of the phenolic compounds, especially anthocyanins, decreased in juice after inoculation. The CIELa*b* analysis indicated that the juice inoculated with L. acidophilus and O. oeni showed a decrease on a* and b* (less red and yellow) but an increase on L (more lightness), whereas the color attributes of L. brevis inoculated juice did not significantly change. Based on this study, L. brevis showed the most optimal performance in the juice due to its better adaptability and fewer effects on the appearance of juice. This study provided a useful reference on the metabolism of lactic acid bacteria in low pH juice and the evolution of primary and secondary nutrients in juice after inoculated with lactic acid bacteria.

Changes Over the Fermentation Period in Phenolic Compounds and Antioxidant and Anticancer Activities of Blueberries Fermented by Lactobacillus plantarum

This study determined the effects of blueberry fermentation by Lactobacillus plantarum on antioxidant and anticancer activities. The fermented blueberries extracted with 80% ethanol (FBE) showed increased superoxide dismutase-like activity, increased scavenging of DPPH and alkyl radicals, and increased antiproliferative activity against human cervical carcinoma HeLa cells by inducing apoptosis. Seven representative phenolic compounds (malvidin 3-O-glucopyranoside, gallic acid, protocatechuic acid, catechol, chlorogenic acid, syringic acid, and epigallocatechin) in FBE were measured by high-performance liquid chromatography at different fermentation times. The content of each phenolic compound in the FBE was dependent on the fermentation period. Protocatechuic acid and catechol levels increased significantly with fermentation time. Of these three major compounds (protocatechuic acid, catechol, and chlorogenic acid), catechol showed the most significant anticancer activity when HeLa cells were treated with each of these three compounds alone or mixed in various ratios. Pearson's product-moment correlation analysis revealed that the increases in antioxidant and anticancer activities following blueberry fermentation were positively correlated with the phenolic acids present in FBE. PRACTICAL APPLICATION: Blueberries fermented with a tannase-producing lactic acid bacteria (LAB), Lactobacillus plantarum showed higher antioxidant activities and antiproliferative activities against human cervical carcinoma HeLa cells than did raw blueberries. L. plantarum fermentation biotransformed blueberry polyphenols into active phenol metabolites with strong antioxidant and antiproliferative activities. Our results suggest that fermented blueberries are rich in phenolic acids, which are a promising source of natural antioxidants and anticancer drugs and can be used as additives in food, pharmaceuticals, and cosmetic preparations.

Volatile Molecule Profiles and Anti-Listeria monocytogenes Activity of Nisin Producers Lactococcus lactis Strains in Vegetable Drinks

This work aimed to evaluate the potential of 15 nisin producing Lactococcus lactis strains, isolated from dairy products, for the fermentation of soymilk and carrot juice. In particular, the acidification and the production of nisin in the food matrices were recorded. Moreover, three strains (LBG2, FBG1P, and 3LC39), that showed the most promising results were further scrutinized for their anti-Listeria monocytogenes activity and volatile molecules profile during fermentation of soymilk and carrot juice. Lactococcus lactis strains LBG2, FBG1P, and 3LC39 resulted the most interesting ones, showing rapid growth and acidification on both food matrices. The higher amounts of nisin were detected in soymilk samples fermented by the strain LBG2 after 24 and 48 h (26.4 mg/L). Furthermore, the rapid acidification combined with the production of nisin resulted in a strong anti-Listeria activity, reducing the pathogen loads below the detection limit, in carrot juice samples fermented by the strains LBG2 and FBG1P and in soymilk by the strain LBG2. The fermentation increased the presence of volatile molecules such as aldehydes and ketones with a positive impact on the organoleptic profile of both the fermented products. These results highlighted the interesting potential of three nisin producing L. lactis strains for the production of fermented carrot juice and soymilk. In fact, the fermentation by lactic acid bacteria, combined or not with other mild technologies, represents a good strategy for the microbiological stabilization of these products. Furthermore, the increase of molecules with a positive sensory impact, such as aldehydes and ketones, in the fermented products suggests a possible improvement of their organoleptic characteristics.

Fermented Momordica charantia L. juice modulates hyperglycemia, lipid profile, and gut microbiota in type 2 diabetic rats

The effect of Lactobacillus plantarum-fermentation on the anti-diabetic functionality of Momordica charantia was examined using a high-fat-diet and low-dose streptozocin-induced type 2 diabetic rat model. Fermented Momordica charantia juice (FMCJ) administration mitigated the hyperglycemia, hyperinsulinemia, hyperlipidemia, and oxidative stress in diabetic rats more favorably than the non-fermented counterpart. Treatments with FMCJ improved ergosterols and lysomonomethyl-phosphatidylethanolamines metabolisms more effectively. Supplement of FMCJ regulated the composition of the gut microbiota, such as increased the abundance of Bacteroides caecigallinarum, Oscillibacter ruminantium, Bacteroides thetaiotaomicron, Prevotella loescheii, Prevotella oralis, and Prevotella melaninogenica, in diabetic rats compared with untreated diabetic rats. Moreover, FMCJ-treated diabetic rats exhibited higher concentrations of acetic acid, propionic acid, butyric acid, total short-chain fatty acids and lower pH values in colonic contents than that in non-fermented juice-treated rats. These results demonstrated that Lactobacillus plantarum-fermentation enhanced the anti-diabetic property of MC juice by favoring the regulation of gut microbiota and the production of SCFAs.

Impact of lactic acid fermentation on acids, sugars, and phenolic compounds in black chokeberry and sea buckthorn juices

The aim of this research was to study the potential of malolactic fermentation to modify the composition of the juices of sea buckthorn, chokeberry and lingonberry. Juices were prepared with and without pectinolytic enzyme treatment, followed by fermentation with commercially available strains of Lactobacillus plantarum, originally isolated from fermented plant materials. The juices before and after the fermentation were analyzed with GC-FID, HPLC-DAD, and HPLC-MS. Enzyme treatment significantly increased the phenolic content in the juices by 11-50%. None of strains showed ability to ferment lingonberry juice. On the other hand, L. plantarum DSM 10492 and DSM 20174 converted all malic acid to lactic acid in sea buckthorn and chokeberry juices, respectively. Fermentation with DSM 10492 reduced the content of flavonols by 9-14% and hydroxycinnamic acids by 20-24% in chokeberry juice. Flavonol glycosides and sugars in sea buckthorn as well as anthocyanins in chokeberry remained unaffected by the fermentation.

Enhanced Antioxidant Activity for Apple Juice Fermented with Lactobacillus plantarum ATCC14917

The present study examined the effect of Lactobacillus plantarum ATCC14917 fermentation on the chemical composition and antioxidant activity of apple juice. Apple juice was fermented and examined of its antioxidant activity using chemical models and cellular antioxidant assay. Furthermore, the chemical composition of fermented apple juice was characterized by LC-MS/MS. Lactobacillus plantarum ATCC14917 fermentation showed an increase in DPPH and ABTS radical scavenging activity as well as cellular antioxidant activity of apple juice. However, fermentation decreased the total phenolic and flavonoid content. Subsequent LC-MS/MS analysis of the phenolic profile indicated that the content of 5-O-caffeoylquinic acid (5-CQA), quercetin, and phloretin with strong antioxidant activity was increased significantly after fermentation. The modified phenolic composition may contribute to the increased antioxidant activity of fermented apple juice. Our findings showed that Lactobacillus plantarum ATCC14917 fermentation may be an efficient way to enhance the bioavailability of phenolic compounds and to protect cells from oxidative stress.

The Influence of Viable Cells and Cell-Free Extracts of Lactobacillus casei on Volatile Compounds and Polyphenolic Profile of Elderberry Juice

In this study, four strains of Lactobacillus casei, as viable cells or cell-free extracts (CFE), were added to elderberry juice in order to evaluate their effect on phenolic and aromatic profile. Two of them were able to grow in juice while the others showed zero-growth. The same strains were lysed and added as extracts in elderberry juice. Multivariate statistical analysis show a separation among samples containing growing cells, non-growing cells, CFE, highlighting the particularities of specific strains. Juices added with CFE presented the highest amount of esters. The strains showing growth phenotype cause an increase of phenyllactic acids. The highest concentration of volatile compounds, particularly of alcohols, terpenes and norisoprenoids (responsible for typical elderberry notes) was observed in samples with strains showing zero-growth. Moreover, a significant increase in anthocyanin content was observed in these samples, suggesting the possible use of Lactobacillus for increasing specific molecules, even for non-multiplying bacterial cell. Considering that this is the first study concerning the use of non-growing cells in fruit juice, the potential of strains is still to be explored and it may have a significant technological application in the development of a microbial collection useful for fruit juice industry.

A review on processing techniques of bast fibers nanocellulose and its polylactic acid (PLA) nanocomposites

The utilization of nanocellulose has increasingly gained attentions from various research fields, especially the field of polymer nanocomposites owing to the growing environmental hazardous of petroleum based fiber products. Meanwhile, the searching of alternative cellulose sources from different plants has become the interests for producing nanocellulose with varying characterizations that expectedly suit in specific field of applications. In this content the long and strong bast fibers from plant species was gradually getting its remarkable position in the field of nanocellulose extraction and nanocomposites fabrications. This review article intended to present an overview of the chemical structure of cellulose, different types of nanocellulose, bast fibers compositions, structure, polylactic acid (PLA) and the most probable processing techniques on the developments of nanocellulose from different bast fibers especially jute, kenaf, hemp, flax, ramie and roselle and its nanocomposites. This article however more focused on the fabrication of PLA based nanocomposites due to its high firmness, biodegradability and sustainability properties in developed products towards the environment. Along with this it also explored a couple of issues to improve the processing techniques of bast fibers nanocellulose and its reinforcement in the PLA biopolymer as final products.

Evaluation of biological and antimicrobial properties of freeze-dried whey fermented by different strains ofLactobacillus plantarum

The aim of this study was to evaluate the biological and antimicrobial activities of commercial freeze-dried whey fermented by lactic acid bacteria in order to valorize this high polluting liquid waste of the dairy industry.