Effects of co-fermented collagen peptide-jackfruit juice on the immune response and gut microbiota in immunosuppressed mice

Preparation, physicochemical characterization, and immunomodulatory activity of ovalbumin peptide-selenium nanoparticles

During the preparation and development of selenium nanoparticles (SeNPs), natural bioactive peptides are added to enhance their physicochemical characteristics and functional properties. Among these properties, immunomodulatory activities, which include activating immune cells to strengthen immunity, constitute the major functions of the immune system. To obtain SeNPs with enhanced immunomodulation, ovalbumin peptide (OP) was used as a stabilizer, yielding OP-SeNPs. The physicochemical properties of OP-SeNPs were characterized. RAW264.7 macrophages were used as a model to investigate the immunomodulatory activity of OP-SeNPs. Results indicate that OP-SeNPs were zero-valent and amorphous, with a particle size of 82.23 ± 1.77 nm. SeNPs demonstrated positive interactions with the -OH, CO, CN, and NH groups of OP. In addition, OP-SeNPs activated RAW264.7 macrophages by increasing NO secretion and enhancing pinocytosis activity, indicating their ability to enhance immunomodulatory effects. Therefore, this study provides a theoretical basis for the construction and characterization of bioactive peptides and SeNP complexes.

Effects of collagen hydrolysate on the stability of anthocyanins: Degradation kinetics, conformational change and interactional characteristics

Anthocyanins are desirable compounds in the food industry owing to their attractive color and high biological activity; however, their poor stability remains a substantial challenge. Here, we show that low-concentration (15 mg/mL) collagen hydrolysate (CH) exhibits a potent stabilization effect on red cabbage anthocyanins (RCAs). CH extended the half-life of RCA by 6.2-fold from 40.7 to 251.1 h. Dynamic light scattering and transmission electron microscopy confirmed the formation of CH-RCA complexes, which exhibited stronger antioxidant activity than RCA alone. Ultraviolet-vis and infrared spectra demonstrated that RCA binding resulted in a more open and disordered CH structure. Centaureidin-3-O-glucoside (C3G) exhibited high affinity for CH, with a binding ratio close to 1.5:1. 1H nuclear magnetic resonance confirmed that the main interaction sites with CH were at the C3G A- and C-rings. This study clarifies how protein hydrolysates protect against anthocyanin degradation from experimental and theoretical aspects.

Lacticaseibacillus rhamnosus LRa05 alleviates cyclophosphamide-induced immunosuppression and intestinal microbiota disorder in mice

Probiotics play a crucial role in regulating the gut microbiota and enhancing immune response. Oral administration of probiotics modulates intestinal microbiota composition and immune homeostasis. In this study, we investigated the immunoregulatory effect of Lacticaseibacillus rhamnosus LRa05 on cyclophosphamide (CTX)-induced immunosuppressive mice. The results showed that oral administration of LRa05 reduced weight loss, restored immune organ indices, and maintained the structural integrity of the intestinal tissue in CTX-treated mice. Moreover, oral administration of LRa05 exhibited immune-modulating properties by promoting the secretion of cytokines (tumor necrosis factor-α, interleukin-1β, interleukin-10, and secretory immunoglobulin A) in serum. Moreover, the analysis of 16S rRNA amplicon sequencing revealed that LRa05 increased gut microbiota diversity and regulated its composition. In detail, LRa05 intervention restored the Firmicutes/Bacteroidota ratio and significantly increased the relative abundance of Lachnospiraceae_NK4A136_group, Oscillibacter, Alloprevotella, Parasutterella, and Roseburia in immunocompromised mice. Conversely, the abundances of Helicobacter, Bacteroides, and unclassified_Desulfovibrionaceae were significantly decreased after administration of LRa05. Based on these findings, orally administered LRa05 could effectively maintain intestinal microbiota homeostasis and regulate immunity, suggesting the potential of L. rhamnosus LRa05 as a candidate probiotic strain in the application of dietary supplement. PRACTICAL APPLICATION: Supplement with L. rhamnosus LRa05 can improve immunity, regulate gut microbiota and promote body health.

Yam protein ameliorates cyclophosphamide-induced intestinal immunosuppression by regulating gut microbiota and its metabolites

Yam is a dual-purpose crop used in both medicine and food that is commonly used as a dietary supplement in food processing. Since yam proteins are often lost during the production of yam starch, elucidating the functionally active value of yam proteins is an important guideline for fully utilizing yam in industrial production processes. This study aimed to explore the potential protective effect of yam protein (YP) on cyclophosphamide (CTX)-induced immunosuppression in mice. The results showed that YP can reduce immune damage caused by CTX by reversing immunoglobulins (IgA, IgG and IgM), cytokines (TNF-α, IL-6, etc.) in the intestines of mice. Moreover, YPs were found to prevent CTX-induced microbiota dysbiosis by enhancing the levels of beneficial bacteria within the microbiome, such as Lactobacillus, and lowering those of Desulfovibrio_R and Helicobacter_A. Metabolomics analyses showed that YP significantly altered differential metabolites (tryptophan, etc.) and metabolic pathways (ABC transporter protein, etc.) associated with immune responses in the gut. Furthermore, important connections were noted between particular microbiomes and metabolites, shedding light on the immunoprotective effects of YPs by regulating gut flora and metabolism. These findings deepen our understanding of the functional properties of YPs and lay a solid foundation for the utilization of yam.

Dynamic high-pressure microfluidization assisted with galactooligosaccharide-modified whey protein isolate: Investigating its effect on relieving intestinal barrier damage

The study aimed to investigating the mechanisms of relieved intestinal barrier damage by dynamic high-pressure microfluidization assisted with galactooligosaccharide- glycated whey protein isolate. The modifications changed the multi-structure, and the modified whey protein isolate could promote the proliferation of IEC-6 cells and contributed to the restoration of LPS-induced occludin damage in IEC-6 cells. Also, it could repair cyclophosphamide-induced ileal villus rupture and crypt destruction in BALB/c mice, significantly altered the abundance of dominant bacteria, which were associated with propionic acid, butyric acid, isovaleric acid, and valeric acid. Ileum transcriptomics revealed that the modified whey protein isolate significantly regulate of the levels of Cstad, Cyp11a1, and Hs6st2 genes, relating to the increase of propionic acid, isovaleric acid, and valeric acid. In conclusion, galactooligosaccharide- modified whey protein isolate could regulate the level of Cstad, Cyp11a1 and Hs6st2 genes by altering the gut microbial structure and the level of SCFAs, thereby repairing the intestinal barrier.

External damp environment aggravates diarrhea in spleen deficiency and dampness syndrome in mice: involvement of small intestinal contents microbiota, energy metabolism, gastrointestinal and fluid functions

Objectives

Recent studies have increasingly demonstrated that a multiplatform water environment combined with lard gavage is an effective method for establishing a mouse model of diarrhea. However, the interactions between intestinal microorganisms and diarrhea, as well as the relationships among energy metabolism, fluid balance, and gastrointestinal function in this model, remain poorly understood.

Methods

Building on previous research, this study aimed to optimiz and replicate a multiplatform water environment combined with a lard gavage model. Male Kunming mice, free of specific pathogens, were randomly divided into four groups: a normal control group (ZC), a standing group (ZL), a standing combined with lard group (ZLZ), and a standing combined with internal and external wet conditions group (ZLZS). The mice in the ZL, ZLZ, and ZLZS groups were subjected to 4 hours of daily standing in a custom-designed multiplatform water environment. Starting on day 8, mice in the ZLZ and ZLZS groups were gavaged with lard (0.4 mL per session, twice daily) for 7 consecutive days, while those in the ZLZS group were additionally exposed to a wet litter environment (50 g/100 mL). The ZC and ZL groups received equal volumes of sterile water via gavage. The microbiota in the small intestine, as well as serum levels of cAMP, cGMP, VIP, Gas, and D-xylose, were analyzed.

Results

Compared with the ZLZ group, the ZLZS group showed significantly lower serum levels of cAMP/cGMP (p<0.01) and Gas (p<0.01). D-xylose levels were lower in the ZL, ZLZ, and ZLZS groups compared to the ZC group, while VIP levels were significantly higher in the ZL and ZLZS groups (p<0.01). Moverover, Corynebacterium, Empedobacter, and Pseudochrobactrum were identified as characteristic bacterial genera in the ZLZS group. The mechanism by which the small intestinal microbiota induces diarrhea was linked to the biosynthesis of secondary bile acids.

Conclusion

A multiplatform water environment combined with lard gavage can effectively induce diarrhea, and the addition of an external wet environment exacerbates this condition by affecting small intestinal contents microbiota and other functions.

In Silico Predicting the Presence of the S100B Motif in Edible Plants and Detecting Its Immunoreactive Materials: Perspectives for Functional Foods, Dietary Supplements and Phytotherapies

The protein S100B is a part of the S100 protein family, which consists of at least 25 calcium-binding proteins. S100B is highly conserved across different species, supporting important biological functions. The protein was shown to play a role in gut microbiota eubiosis and is secreted in human breast milk, suggesting a physiological trophic function in newborn development. This study explores the possible presence of the S100B motif in plant genomes, and of S100B-like immunoreactive material in different plant extracts, opening up potential botanical uses for dietary supplementation. To explore the presence of the S100B motif in plants, a bioinformatic workflow was used. In addition, the immunoreactivity of S100B from vegetable and fruit samples was tested using an ELISA assay. The S100B motif was expected in silico in the genome of different edible plants belonging to the Viridiplantae clade, such as Durio zibethinus or Malus domestica and other medicinal species. S100B-like immunoreactive material was also detected in samples from fruits or leaves. The finding of S100B-like molecules in plants sheds new light on their role in phylogenesis and in the food chain. This study lays the foundation to elucidate the possible beneficial effects of plants or derivatives containing the S100B-like principle and their potential use in nutraceuticals.

Recent advances of fermented fruits: A review on strains, fermentation strategies, and functional activities

Fruits are recognized as healthy foods with abundant nutritional content. However, due to their high content of sugar and water, they are easily contaminated by microorganisms leading to spoilage. Probiotic fermentation is an effective method to prevent fruit spoilage. In addition, during fermentation, the probiotics can react with the nutrients in fruits to produce new derived compounds, giving the fruit specific flavor, enhanced color, active ingredients, and nutritional values. Noteworthy, the choice of fermentation strains and strategies has a significant impact on the quality of fermented fruits. Thus, this review provides comprehensive information on the fermentation strains (especially yeast, lactic acid bacteria, and acetic acid bacteria), fermentation strategies (natural or inoculation fermentation, mono- or mixed-strain inoculation fermentation, and liquid- or solid-state fermentation), and the effect of fermentation on the shelf life, flavor, color, functional components, and physiological activities of fruits. This review will provide a theoretical guidance for the production of fermented fruits.

Dual-ROS Sensitive Moieties Conjugate Inhibits Curcumin Oxidative Degradation for Colitis Precise Therapy

Curcumin, a natural bioactive polyphenol with diverse molecular targets, is well known for its anti-oxidation and anti-inflammatory potential. However, curcumin exhibits low solubility (<1 µg mL-1), poor tissue-targeting ability, and rapid oxidative degradation, resulting in poor bioavailability and stability for inflammatory therapy. Here, poly(diselenide-oxalate-curcumin) nanoparticle (SeOC-NP) with dual-reactive oxygen species (ROS) sensitive chemical moieties (diselenide and peroxalate ester bonds) is fabricated by a one-step synthetic strategy. The results confirmed that dual-ROS sensitive chemical moieties endowed SeOC-NP with the ability of targeted delivery of curcumin and significantly suppress oxidative degradation of curcumin for high-efficiency inflammatory therapy. In detail, the degradation amount of curcumin for SeOC is about 4-fold lower than that of free curcumin in an oxidative microenvironment. As a result, SeOC-NP significantly enhanced the antioxidant activity and anti-inflammatory efficacy of curcumin in vitro analysis by scavenging intracellular ROS and suppressing the secretion of nitric oxide and pro-inflammatory cytokines. In mouse colitis models, orally administered SeOC-NP can remarkably alleviate the symptoms of IBD and maintain the homeostasis of gut microbiota. This work provided a simple and effective strategy to fabricate ROS-responsive micellar and enhance the oxidation stability of medicine for precise therapeutic inflammation.

Fermented foods: Harnessing their potential to modulate the microbiota-gut-brain axis for mental health

Over the past two decades, whole food supplementation strategies have been leveraged to target mental health. In addition, there has been increasing attention on the ability of gut microbes, so called psychobiotics, to positively impact behaviour though the microbiota-gut-brain axis. Fermented foods offer themselves as a combined whole food microbiota modulating intervention. Indeed, they contain potentially beneficial microbes, microbial metabolites and other bioactives, which are being harnessed to target the microbiota-gut-brain axis for positive benefits. This review highlights the diverse nature of fermented foods in terms of the raw materials used and type of fermentation employed, and summarises their potential to shape composition of the gut microbiota, the gut to brain communication pathways including the immune system and, ultimately, modulate the microbiota-gut-brain axis. Throughout, we identify knowledge gaps and challenges faced in designing human studies for investigating the mental health-promoting potential of individual fermented foods or components thereof. Importantly, we also suggest solutions that can advance understanding of the therapeutic merit of fermented foods to modulate the microbiota-gut-brain axis.

Holothuria leucospilota polysaccharides (HLP) ameliorate colitis rats via regulation of the metabolic profiling and TLR4/NLRP3 signaling pathways

Recently, the development of natural polysaccharides for ameliorating immunity and gut metabolism has attracted extensive attention. This study used Holothuria leucospilota polysaccharides (HLP) to explore the improvement mechanism in ulcerative colitis rats on perspectives of immunity and metabolism. The results showed that HLP increased goblet cells’ number and the content of tight junction proteins (zona occludens 1 and occludin) and improved intestinal barrier permeability. The levels of immune cytokines (IL‐4, IL‐6, IL‐10, IL‐18, TNF‐α, and IL‐1β) and the activity of oxidative stress‐related enzymes (superoxide dismutase, catalase, malondialdehyde, and glutathione peroxidase) were regulated. HLP regulated the related genes and proteins expression of immune cytokines, MAPK, and NLRP3 inflammasome. Furthermore, HLP treatment increased the concentration of short‐chain fatty acids (SCFAs) and regulated serum metabolic disorders by regulating amino acid metabolism, SCFA metabolism, and energy metabolism. These results provide a new perspective for developing HLP as a promising functional food for preventing and mitigating colitis.

Current situation, trend, and prospects of research on functional components from by-products of baijiu production: A review

In the present scenario marked by energy source shortages and escalating concerns regarding carbon dioxide emissions, there is a growing emphasis on the optimal utilization of biomass resources. Baijiu, as the Chinese national spirit, boasts remarkably high sales volumes annually. However, the production of baijiu yields various by-products, including solid residues (Jiuzao), liquid wastewater (Huangshui and waste alcohol), and gaseous waste. Recent years have witnessed dedicated research aimed at exploring the composition and potential applications of these by-products, seeking sustainable development and comprehensive resource utilization. This review systematically summarizes recent research, shedding light on both the baijiu brewing process and the bioactive compounds present baijiu production by-products (BPBPs). The primary focus lies in elucidating the potential extraction methods and applications of BPBPs, offering a practical approach to comprehensive utilization of by-products in functional food, medicine, cosmetic, and packaging fields. These applications not only contribute to enhancing production efficiency and mitigating environmental pollution, but also introduce innovative concepts for the sustainable advancement of associated industries. Future research avenues may include more in-depth compositional analysis, the development of utilization technologies, and the promotion of potential industrialization.

Lactobacillus acidophilus-Fermented Jujube Juice Ameliorates Chronic Liver Injury in Mice via Inhibiting Apoptosis and Improving the Intestinal Microecology

SCOPE

Chronic liver diseases are clinically silent and responsible for significant morbidity and mortality worldwide. Jujube has displayed various biological activities. Here, the therapeutic effect of Lactobacillus acidophilus (L. acidophilus)-fermented jujube juice (FJJ) and the possible mechanism against chronic liver injury (CLI) in mice are further studied.

METHODS AND RESULTS

After the CCl4 -induced CLI mice are separately treated with L. acidophilus (LA), unfermented jujube juice (UFJJ), and FJJ, FJJ but not LA or UFJJ suppresses the liver index. By using H&E staining, immunofluorescence staining, RT-PCR, and western blotting, it is shown that LA, UFJJ, and FJJ intervention ameliorate hepatocyte necrosis, inhibit the mRNA levels of pro-inflammatory (NLRP3, Caspase-1, IL-1β, and TNF-α) and fibrosis-associated factors (TGF-β1, LXRα, and MMP2). Also, FJJ displays significant protection against mucosal barrier damage in CLI mice. Among the three interventions, FJJ exhibits the best therapeutic effect, followed by UFJJ and LA. Furthermore, FJJ improves dysbiosis in CLI mice.

CONCLUSIONS

This study suggests that FJJ exhibits a protective effect against CCl4 -induced CLI mice by inhibiting apoptosis and oxidative stress, regulating liver lipid metabolism, and improving gut microecology. Jujube juice fermentation with L. acidophilus can be a food-grade supplement in treating CLI and related liver diseases.

Peptidome comparison on the immune regulation effects of different casein fractions in a cyclophosphamide mouse model

The protein composition of human milk plays a crucial role in infant formula milk powder formulation. Notably, significant differences exist between bovine casein and human milk casein. Previous studies have shown that casein hydrolysates could enhance immune function; however, gastrointestinal dyspepsia in infants affects the type and function of peptides. Therefore, the present study used peptidomics to sequence and analyze hydrolyzed peptides from different casein fractions. Additionally, animal experiments were conducted to assess the functionality of these casein fractions and elucidate their differences. The results revealed variations in peptide composition among the different casein fractions of formula milk powder. Interestingly, milk powder formulated with both β- and κ-casein (BK) exhibited significant enrichment of peptides related to the immune system. Moreover, the BK group significantly alleviated immune organ damage in cyclophosphamide-treated mice and regulated serum levels of pro-inflammatory and anti-inflammatory factors. Furthermore, feeding different casein fractions influenced the intestinal microflora of cyclophosphamide-treated mice, with the BK group mitigating the changes caused by cyclophosphamide. In conclusion, the findings suggest that BK formula in milk powder has the potential to positively enhance immunity. This study provides a robust theoretical basis for human-emulsified formula milk powder development.

Arjunolic acid protects the intestinal epithelial barrier, ameliorating Crohn's disease-like colitis by restoring gut microbiota composition and inactivating TLR4 signalling

BACKGROUND AND AIMS

Crohn's disease (CD) is characterized by an overabundance of epithelial cell death and an imbalance in microflora, both of which contribute to the dysfunction of the intestinal barrier. Arjunolic acid (AA) has anti-apoptotic effects and regulates microbiota efficacy. The objective of this study was to assess the impact of the treatment on colitis resembling Crohn's disease, along with exploring the potential underlying mechanism.

METHODS

CD animal models were created using Il-10-/- mice, and the impact of AA on colitis in mice was evaluated through disease activity index, weight fluctuations, pathological examination, and assessment of intestinal barrier function. To clarify the direct role of AA on intestinal epithelial cell apoptosis, organoids were induced by LPS, and TUNEL staining was performed. To investigate the potential mechanisms of AA in protecting the intestinal barrier, various methods including bioinformatics analysis and FMT experiments were employed.

RESULTS

The treatment for AA enhanced the condition of colitis and the function of the intestinal barrier in Il-10-/- mice. This was demonstrated by the amelioration of weight loss, reduction in tissue inflammation score, and improvement in intestinal permeability. Moreover, AA suppressed the apoptosis of intestinal epithelial cells in Il-10-/- mice and LPS-induced colon organoids, while also reducing the levels of Bax and C-caspase-3. In terms of mechanism, AA suppressed the activation of TLR4 signaling in Il-10-/- mice and colon organoids induced by LPS. In addition, AA increased the abundance of short-chain fatty acid-producing bacteria in the stool of Il-10-/- mice, and transplantation of feces from AA-treated mice improved CD-like colitis.

CONCLUSIONS

The results of our study demonstrate that AA has a protective effect on the intestinal barrier in Crohn's disease-like colitis by preventing apoptosis. Additionally, this groundbreaking study reveals the capacity of AA to hinder TLR4 signaling and alter the makeup of the intestinal microbiome. The findings present fresh possibilities for treating individuals diagnosed with Crohn's disease. AA offers a hopeful novel strategy for managing Crohn's disease by obstructing crucial pathways implicated in intestinal inflammation and enhancing the gut microbiota.

Immune regulation by fermented milk products: the role of the proteolytic system of lactic acid bacteria in the release of immunomodulatory peptides

Food allergies have emerged as a pressing health concern in recent years, largely due to food resources and environmental changes. Dairy products fermented by lactic acid bacteria play an essential role in mitigating allergic diseases. Lactic acid bacteria have been found to possess a distinctive proteolytic system comprising a cell envelope protease (CEP), transporter system, and intracellular peptidase. Studying the impact of different Lactobacillus proteolytic systems on the destruction of milk allergen epitopes and their potential to alleviate allergy symptoms by releasing peptides containing immune regulatory properties is a valuable and auspicious research approach. This paper summarizes the proteolytic systems of different species of lactic acid bacteria, especially the correlation between CEPs and the epitopes from milk allergens. Furthermore, the mechanism of immunomodulatory peptide release was also concluded. Finally, further research on the proteolytic system of lactic acid bacteria will provide additional clinical evidence for the possible treatment and/or prevention of allergic diseases with specific fermented milk/dairy products in the future.

Long-term consumption of different doses of Grifola frondosa affects immunity and metabolism: correlation with intestinal mucosal microbiota and blood lipids

Grifola frondosa (GF) is an edible mushroom with hypoglycemic and hypolipidemic effects. In this study, the specific pathogen-free male mice were randomized into the normal (NM), low-dose GF (LGF), medium-dose GF (MGF), and high-dose GF (HGF) groups. The LGF, MGF, and HGF groups were fed with 1.425 g/(kg d), 2.85 g/(kg d), and 5.735 g/(kg d) of GF solution for 8 weeks. After feeding with GF solution, compared with the NM group, the thymus index was significantly increased in the LGF group, and TC, TG, and LDL of mice were significantly increased in the HGF group, while HDL was significantly decreased. Compared with the NM group, the uncultured Bacteroidales bacterium, Ligilactobacillus increased in the LGF group, and Candidatus Arthromitus increased in the MGF group. The characteristic bacteria of the HGF group included Christensenellaceae R7, unclassified Clostridia UCG 014, unclassified Eubacteria coprostanoligenes, and Prevotellaceae Ga6A1. Among them, Ligilactobacillus showed a negative correlation with HDL. Unclassified Eubacterium coprostanoligenes group and Ligilactobacillus showed a positive correlation with TG. In summary, our experiments evidenced that GF improves lipid metabolism disorders by regulating the intestinal microbiota, providing a new pathway for hypolipidemic using GF dietary.

Sea Cucumber Hydrolysate Alleviates Immunosuppression and Gut Microbiota Imbalance Induced by Cyclophosphamide in Balb/c Mice through the NF-κB Pathway

This study aimed to investigate the effect of sea cucumber hydrolysate (SCH) on immunosuppressed mice induced by cyclophosphamide (Cy). Our findings demonstrated that SCH could increase the thymus index and spleen index, decrease the serum alanine transaminase (ALT) and aspartate aminotransferase (AST) levels, increase the serum IgG and small intestinal sIgA levels, reduce small intestinal and colon tissue damage, and activate the nuclear factor-κB (NF-κB) pathway by increasing TRAF6 and IRAK1 protein levels, as well as the phosphorylation levels of IκBα and p65, thereby enhancing immunity. In addition, SCH alleviated the imbalance of the gut microbiota by altering the composition of the gut microbiota in immunosuppressed mice. At the genus level, when compared with the model group, the relative abundance of Dubosiella, Lachnospiraceae, and Ligilactobacillus increased, while that of Lactobacillus, Bacteroides, and Turicibacter decreased in the SCH groups. Moreover, 26 potential bioactive peptides were identified by oligopeptide sequencing and bioactivity prediction. This study's findings thus provide an experimental basis for further development of SCH as a nutritional supplement to alleviate immunosuppression induced by Cy as well as provides a new idea for alleviating intestinal damage induced by Cy.

Antioxidant and Immune Stimulating Effects of Allium cepa Skin in the RAW 264.7 Cells and in the C57BL/6 Mouse Immunosuppressed by Cyclophosphamide

Allium cepa L. (onion) has been reported to have various pharmacological effects, such as preventing heart disease, and improving antimicrobial activity and immunological effects. The Republic of Korea produced 1,195,563 tons of onions (2022). The flesh of onion is used as food while the onion skin (OS) is thrown away as an agro-food by-product and is considered to induce environmental pollution. Thus, we hypothesize that increasing usage of OS as functional food material could help protect from the environment pollution. The antioxidant effects and immune-enhancing effects of OS were evaluated as functional activities of OS. In this study, OS showed high 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities and xanthine oxidase (XO) inhibitory activity. The antioxidant activities increased in a dose-dependent manner. The IC50 values of DPPH, ABTS radical scavenging activity, and XO inhibitory activity were 954.9 μg/mL, 28.0 μg/mL, and 10.7 μg/mL, respectively. Superoxide dismutase and catalase activities of OS in RAW 264.7 cells were higher than those of the media control. There was no cytotoxicity of OS found in RAW 264.7 cells. Nitric oxide and cytokines (IL-1β, IL-6, IFN-γ, and TNF-α) concentrations in RAW 264.7 cells significantly increased in a dose dependent manner. Immune-stimulating effects of OS were evaluated in immunosuppressed mice induced by cyclophosphamide. White blood cell count and the B cell proliferation of splenocytes were higher in OS100 (OS extract 100 mg/kg body weight) and OS200 (OS extract 200 mg/kg body weight) groups than in the negative control (NC) group. Serum IgG and cytokine (IL-1β and IFN-γ) levels were also higher in OS100 and OS200 groups than in the NC group. OS treatment increased NK cell activity compared with the NC group. The results suggested that OS can improve antioxidant and immune stimulating effects. The use of OS as functional supplement can reduce the agro-food by-product and it may contribute to carbon neutrality.

Effects of Lactobacillus casei NCU011054 on immune response and gut microbiota of cyclophosphamide induced immunosuppression mice

Lactobacillus (L.) casei NCU011054 isolated from infant feces has been proven to be a potential probiotic in vitro. The present study aimed to investigate the effects of L. casei NCU011054 on the immune response and gut microbiota in cyclophosphamide (CP)-induced immunosuppression mice. Results indicated that L. casei NCU011054 could increase the levels of mucin (Muc2) and tight junction proteins (ZO-1, occludin and claudin-1). Moreover, L. casei NCU011054 was found to upregulate TLRs/NF-κB pathway (TLR-2, TLR-4, TLR-6, p65 and NF-κB) and two transcription factors (T-bet and GATA-3) mRNA levels, and enhance the number of CD4⁺T cells. Th1-related cytokines (IL-12p70, IFN-γ and TNF-α) and Th2-related cytokines (IL-2, IL-4, IL-6 and IL-10) significantly increased after L. casei NCU011054 treatment. More importantly, L. casei NCU011054 increased the ratio of T-bet to GATA-3 and IFN-γ to IL-4. Apart from these, L. casei NCU011054 remodeled gut microbiota and modulated gut metabolites in CP-induced immunosuppressed mice. The correlation analysis showed that Lactobacillus upregulated by L. casei NCU011054 was positively correlated with TLRs/NF-κB pathway, and the ratio of T-bet to GATA-3 and IFN-γ to IL-4. All findings revealed that L. casei NCU011054 could improve intestinal immune dysfunction and modulate Th1/Th2 balance via TLRs/NF-κB pathway in CP-induced immunosuppressed mice.

The diarrheal mechanism of mice with a high-fat diet in a fatigued state is associated with intestinal mucosa microbiota

Growing evidence has demonstrated that fatigue and a high-fat diet trigger diarrhea, and intestinal microbiota disorder interact with diarrhea. However, the association of intestinal mucosal microbiota with fatigue and high-fat diet trigger diarrhea remains unclear. The specific pathogen-free Kunming male mice were randomly divided into the normal group (MCN), standing group (MSD), lard group (MLD), and standing united lard group (MSLD). Mice in the MSD and MSLD groups stood on the multiple-platform apparatus for four h/d for fourteen consecutive days. From the eighth day, mice in the MLD and MSLD groups were intragastric lard, 0.4 mL/each, twice a day for seven days. Subsequently, we analyzed the characteristics and interaction relationship of intestinal mucosal microbiota, interleukin-6 (IL-6), interleukin-17 (IL-17), malondialdehyde (MDA), superoxide dismutase (SOD), and secretory immunoglobulin A (sIgA). Results showed that mice in the MSLD group had an increased number of bowel movements. Compared with the MCN group, the contents of IL-17, and IL-6 were higher (p > 0.05), and the content of sIgA was lower in the MSLD group (p > 0.05). MDA and SOD increased in MLD and MSLD groups. Thermoactinomyces and Staphyloccus were the characteristic bacteria of the MSLD group. And Staphyloccus were positively correlated with IL-6, IL-17, and SOD. In conclusion, the interactions between Thermoactinomyces, Staphyloccus and intestinal inflammation, and immunity might be involved in fatigue and high-fat diet-induced diarrhea.

American ginseng with different processing methods ameliorate immunosuppression induced by cyclophosphamide in mice via the MAPK signaling pathways

This study aimed to clarify the effects of two processed forms of American ginseng (Panax quinquefolius L.) on immunosuppression caused by cyclophosphamide (CTX) in mice. In the CTX-induced immunosuppressive model, mice were given either steamed American ginseng (American ginseng red, AGR) or raw American ginseng (American ginseng soft branch, AGS) by intragastric administration. Serum and spleen tissues were collected, and the pathological changes in mice spleens were observed by conventional HE staining. The expression levels of cytokines were detected by ELISA, and the apoptosis of splenic cells was determined by western blotting. The results showed that AGR and AGS could relieve CTX-induced immunosuppression through the enhanced immune organ index, improved cell-mediated immune response, increased serum levels of cytokines (TNF-α, IFN-γ, and IL-2) and immunoglobulins (IgG, IgA, and IgM), as well as macrophage activities including carbon clearance and phagocytic index. AGR and AGS downregulated the expression of BAX and elevated the expression of Bcl-2, p-P38, p-JNK, and p-ERK in the spleens of CTX-injected animals. Compared to AGS, AGR significantly improved the number of CD4⁺CD8^-T lymphocytes, the spleen index, and serum levels of IgA, IgG, TNF-α, and IFN-γ. The expression of the ERK/MAPK pathway was markedly increased. These findings support the hypothesis that AGR and AGS are effective immunomodulatory agents capable of preventing immune system hypofunction. Future research may investigate the exact mechanism to rule out any unforeseen effects of AGR and AGS.

Collagen peptide promotes DSS-induced colitis by disturbing gut microbiota and regulation of macrophage polarization

Ulcerative colitis (UC) is an inflammatory bowel disease caused by mucosal immune system disorder, which has increased steadily all over the world. Previous studies have shown that collagen peptide (CP) has various beneficial biological activities, it is not clear whether the effect of CP on UC is positive or negative. In this study, 2.5% dextran sulfate sodium (DSS) was used to establish acute colitis in mice. Our results suggested that CP supplementation (200, 400 mg/kg/day) promoted the progression of colitis, increased the expression of inflammatory factors and the infiltration of colonic lamina propria macrophages. Gut microbiota analysis showed the composition changed significantly and inflammation promoted bacteria was after CP treatment. Meanwhile, the effect of CP on macrophage polarization was further determined in Raw264.7 cell line. The results showed that CP treatment could increase the polarization of M1 macrophages and promote the expression of inflammatory factors. In conclusion, our results showed that CP treatment could disrupt the gut microbiota of host, promote macrophage activation and aggravate DSS-induced colitis. This may suggest that patients with intestinal inflammation should not take marine derived CP.

Fermented natural product targeting gut microbiota regulate immunity and anti-inflammatory activity: A possible way to prevent COVID-19 in daily diet

Low immune function makes the body vulnerable to being invaded by external bacteria or viruses, causing influenza and inflammation of various organs, and this trend is shifting to the young and middle-aged group. It has been pointed out that natural products fermented by probiotic have benign changes about their active ingredients in some studies, and it have shown strong nutritional value in anti-oxidation, anti-aging, regulating lipid metabolism, anti-inflammatory and improving immunity. In recent years, the gut microbiota plays a key role and has been extensively studied in improving immunity and anti-inflammation activity. By linking the relationship between natural products fermented by probiotic, gut microbiota, immunity, and inflammation, this review presents the modulating effects of probiotics and their fermented natural products on the body, including immunity-enhancing and anti-inflammatory activities by modulating gut microbiota, and it is discussed that the current understanding of its molecular mechanisms. It may become a possible way to prevent COVID-19 through consuming natural products fermented by probiotic in our daily diet.

Effects of low molecular weight peptides from monkfish (Lophius litulon) roe on immune response in immunosuppressed mice

This study aimed to investigate the immunomodulatory activation of low-molecular-weight peptides from monkfish (Lophius litulon) roe (named MRP) on cyclophosphamide (CTX)-induced immunosuppressed mice. Our results indicated that MRP (100 mg/kg/d BW) could significantly increase the body weight and immune organ index, and improve the morphological changes in the spleen and thymus of mice. These effects subsequently enhance the serum levels of interleukin (IL)-6, IL-1β, tumor necrosis factor (TNF)-α, and immunoglobulin (Ig) A, IgM, and IgG. Furthermore, MRP could also improve CTX-induced oxidative stress, and activate the NF-κB and MAPK pathways in the spleen tissues. The findings reported herein indicate that MRP has a good immunomodulatory activation toward immunosuppressed mice, hence can potentially be developed as an immune adjuvant or functional food.

Effect and mechanism of functional compound fruit drink on gut microbiota in constipation mice

Compound fruit drink (CFD) is a functional drink prepared with fruit, Chinese herbs and prebiotic fructooligosaccharide as the main ingredients. Loperamide hydrochloride was used to establish a mouse model of constipation. And the effect of CFD on the improvement of constipation and the impact on gut microbiota were studied. The results showed that CFD significantly enhanced intestinal motility in constipated mice (P < 0.05). It significantly improved serum levels of gastrointestinal regulatory-related peptides, elevated the short-chain fatty acids (SCFAs) content and alleviated colonic injury. Meanwhile, CFD also up-regulated the mRNA expression levels of AQP3, AQP9, SCF and c-Kit and the related protein expression levels. Fecal microbial results showed that the CFD medium-dose group significantly increased species richness. Furthermore, CFD increased the abundance of potentially beneficial bacteria and reduced the number of potentially pathogenic bacteria. This study indicated that CFD was a promising functional drink for effectively relieving constipation.

Sustainable Food Systems: The Case of Functional Compounds towards the Development of Clean Label Food Products

The addition of natural components with functional properties in novel food formulations confers one of the main challenges that the modern food industry is called to face. New EU directives and the global turn to circular economy models are also pressing the agro-industrial sector to adopt cradle-to-cradle approaches for their by-products and waste streams. This review aims to present the concept of “sustainable functional compounds”, emphasizing on some main bioactive compounds that could be recovered or biotechnologically produced from renewable resources. Herein, and in view of their efficient and “greener” production and extraction, emerging technologies, together with their possible advantages or drawbacks, are presented and discussed. Μodern examples of novel, clean label food products that are composed of sustainable functional compounds are summarized. Finally, some action plans towards the establishment of sustainable food systems are suggested.

Co-fermented cow milk protein by Lactobacillus helveticus KLDS 1.8701 and Lactobacillus plantarum KLDS 1.0386 attenuates its allergic immune response in Balb/c mice

Milk protein is one of the major food allergens. As an effective processing method, fermentation may reduce the potential allergenicity of allergens. This study aimed to evaluate the therapeutic potential of co-fermented milk protein using Lactobacillus helveticus KLDS 1.8701 and Lactobacillus plantarum KLDS 1.0386 in cow milk protein allergy (CMPA) management. This study determined the secondary and tertiary structures of the fermented versus unfermented proteins by Fourier-transform infrared spectroscopy and surface hydrophobicity to evaluate its conformational changes. Our results showed that different fermentation methods have significantly altered the conformational structures of the cow milk protein, especially the tertiary structure. Further, the potential allergenicity of the fermented cow milk protein was assessed in Balb/c mice, and mice treated with the unfermented milk and phosphate-buffered saline were used as a control. We observed a significant reduction in allergenicity via the results of the spleen index, serum total IgE, specific IgE, histamine, and mouse mast cell protease 1 in the mice treated with the co-fermented milk protein. In addition, we analyzed the cytokines and transcription factors expression levels of spleen and jejunum and confirmed that co-fermentation could effectively reduce the sensitization of cow milk protein by regulating the imbalance of T helper (Th1/Th2 and Treg/Th17). This study suggested that changes of conformational structure could reduce the potential sensitization of cow milk protein; thus, fermentation may be a promising strategy for developing a method of hypoallergenic dairy products.

Mulberry leaf meal: A potential feed supplement for juvenile Megalobrama amblycephala "Huahai No. 1"

This study was performed to evaluate the potential application of mulberry leaf meal (ML) and fermented mulberry leaf meal (FML) as feed supplements in aquatic animals for developing varieties of practical and economical feed ingredients. Juveniles Megalobrama amblycephala were fed a basal diet (35.7% crude protein, 10.4% crude lipid; control group) supplemented with 2.22% and 4.44% mulberry leaf meals (ML2, ML4) and fermented mulberry leaf meals (FML2, FML4) for 8 weeks. Generally, the two-way ANOVA showed the supplementation level exhibited a prominent effect on the growth performance and physiological status of fish. Furthermore, the two-way ANOVA showed the supplementary fermented mulberry leaf meal increased plasma complement 4 (C4) content (P < 0.05). The weight gain rate (WGR, 145.87%) and the specific growth rate (SGR, 1.63%) were significantly increased in FML2 group compared with the control group (P < 0.05). The muscle crude lipid content and hepatosomatic index (HSI) were higher in FML2 group than that in ML2 group (P < 0.05). The hepatic GSH content in ML4 group and CAT, T-SOD activities in FML4 group were significantly increased compared with the control group (P < 0.05). The hepatic MDA content in FML4 group was significantly decreased compared with the FML2 group (P < 0.05). Total cholesterol (TC) contents showed a significant decrease in ML4 and FML4 groups compared with the control group (P < 0.05). Regarding the gene expression, sirtiun 1 (Sirt1) gene expression was elevated in FML2 group compared with the ML2 group (P < 0.05). Compare to the control group, FML2 diet significantly increased the expression of i-kappa-B alpha (IKBα) gene in liver, and decreased the expression of forkhead box O1 α (FoxO1α), toll-like receptors 4 (TLR4) and nuclear factor-kappa B (NF-κB) genes (P < 0.05). In conclusion, 2.22% FML promoted the growth performance of M. amblycephala and enhanced the anti-inflammatory responses by inhibiting TLR4/NF-κB signaling pathway. On the other hand, 4.44% FML reduced plasma lipid content (hypolipedemic effect) and improved the hepatic antioxidant capacity of M. amblycephala.

Two Laminaria japonica polysaccharides with distinct structure characterization affect gut microbiota and metabolites in hyperlipidemic mice differently

Our previous study found dietary mannogluconic acid (MA) and fucogalactan sulfate (FS) from Laminaria japonica have distinct structure characterization and potential hypolipidemic effects in vitro. Herein, we compared the benefits of MA and FS on hyperlipidemia. The result showed only FS treatment decreased body weight and serum cholesterol levels. Compared with MA, FS was more effective in mitigating hepatic fat accumulation, promoting GSH-Px activity, reducing the MDA formation, and lowering the level of TNF-α in liver. Gut microbiota and metabolism analysis revealed that FS increased the relative abundance of beneficial bacteria and boosted the level of short chain fatty acids. Particularly, taurine and 3α,7α,12α-trihydroxy-24-oxo-5-β-cholestanoyl CoA were upregulated by FS, which might attribute to the increased Oscillibacter and thus affect the enterohepatic circulation of bile acids and serum TC level. Therefore, FS with more branches and sulfate ester groups could be a good lipid-lowering dietary supplement.

Phytochemical composition, antioxidant activities and immunomodulatory effects of pigment extracts from Wugong Mountain purple red rice bran

The study was to investigate the phytochemical composition, antioxidant activities and the immunomodulatory effects on cyclophosphamide-induced (cy-induced) immunosuppressed mice of purple red rice bran pigment extracts (PRBP). The phytochemical composition of total anthocyanins, total phenolic and total flavonoid contents were evaluated. Moreover, UV-Vis, FT-IR and UPLC-ESI-QTOF-MS spectra analysis identified for the first time the presence of seventeen anthocyanins in PRBP, including five anthocyanin aglycones and twelve acetylated anthocyanins, suggesting that PRBP were a highly acylated anthocyanin profile. The DPPH, ABTS⁺, hydroxyl radical scavenging activity and FRAP assays showed that PRBP had excellent antioxidant activities. Further, the results of animal experiments showed that PRBP alleviated immune organ damage and recovered damaged immune function, such as preventing the reduction of body weight, spleen and thymus organ indexes, and significantly increasing the levels of TNF-α, IL-6 and IL-1β in spleen which indicated that PRBP alleviated immunosuppression in Cy-induced mice. The immunomodulatory activity of PRBP was reflected by the upregulation of MAPK signaling pathways after gavage. Taken together, these results suggest that PRBP possessed a certain antioxidant and immunomodulatory abilities. These findings will lead to a better understanding of the biological properties of PRBP and broaden its utilization in food processing.

Effects of Fucoidan Isolated From Laminaria japonica on Immune Response and Gut Microbiota in Cyclophosphamide-Treated Mice

The effects of Laminaria japonica fucoidan (LF) on immune regulation and intestinal microflora in cyclophosphamide (CTX)-treated mice were investigated in this work. Results indicated that LF significantly enhanced the spleen and thymus indices, promoted spleen lymphocyte and peritoneal macrophages proliferation, and increased the immune-related cytokines production in serum. Moreover, LF could regulate intestinal flora composition, increasing the abundance of Lactobacillaceae and Alistipes, and inhibiting Erysipelotrichia, Turicibacter, Romboutsia, Peptostreptococcaceae, and Faecalibaculum. These results were positively correlated with immune characteristics. Overall, LF could be useful as a new potential strategy to mitigate CTX immunosuppression and intestinal microbiota disorders.