Polyphenolic bioactives as an emerging group of nutraceuticals for promotion of gut health: A review

Sea buckthorn polyphenols on gastrointestinal health and the interactions with gut microbiota

The potential health benefits of sea buckthorn polyphenols (SBP) have been extensively studied, attracting increasing attention from researchers. This paper reviews the composition of SBP, the effects of processing on SBP, its interactions with nutrients, and its protective role in the gastrointestinal tract. Polyphenols influence nutrient absorption and metabolism by regulating the intestinal flora, thereby enhancing bioavailability, protecting the gastrointestinal tract, and altering nutrient structures. Additionally, polyphenols exhibit anti-inflammatory and immunomodulatory effects, promoting intestinal health. The interaction between polyphenols and intestinal flora plays a significant role in gastrointestinal health, supporting the composition and diversity of the gut microbiota. However, further research is needed to emphasize the importance of human trials and to explore the intricate relationship between SBP and gut microbiota, as these insights are crucial for understanding the mechanisms underlying SBP's benefits for the gastrointestinal tract (GIT).

Biological Mechanisms of Polyphenols against Clostridium Difficile: A Systematic Review

BACKGROUND

Clostridium difficile is an opportunistic infection that can lead to antibiotic- associated diarrhea and toxic megacolon.

OBJECTIVE

This systematic review study aimed to investigate polyphenols' antibacterial and antitoxin properties and their effects on reducing complications related to C. difficile Infections (CDI).

METHODS

This systematic review was conducted following the PRISMA guideline 2020. Multiple databases, including Web of Science, PubMed, Cochrane Library, EMBASE, and Scopus, were searched thoroughly for existing literature. After considering the inclusion and exclusion criteria for the review, 18 articles were included. Data were collected and registered into an Excel file for further investigations and conclusions.

RESULTS

Polyphenols by reducing Reactive Oxygen Species (ROS) levels, increasing inflammatory factor Interleukin 10 (IL-10), reducing Nuclear Factor kappa B (NF-κB) and Tumour Necrosis Factor- α (TNF-α), IL-6, IL-1α, IL-1β, Granulocyte Colony-stimulating Factor (G-CSF), and Monocyte Chemoattractant Protein-1 (MCP-1) and Macrophage Inflammatory Protein-1 alpha (MIP-1α) levels, and regulating the expression of Bcl-2 and Bax, make the growth and replication conditions of C. difficile more difficult and prevent it from producing toxins. Furthermore, polyphenols can exhibit prebiotic properties, promoting the growth of beneficial Bifidobacterium and Lactobacillus species and consequently regulating gut microbiota, exerting antimicrobial activities against C. difficile. They also induce their beneficial effects by inhibiting the production of C. difficile TcdA and TcdB.

CONCLUSION

Polyphenols have been reported to inhibit C. difficile growth and toxin production by several mechanisms in preclinical studies. However, more clinical studies are needed to investigate their safety in humans.

Ferrous Pyrophosphate and Mixed Divalent Pyrophosphates as Delivery Systems for Essential Minerals

Poorly water-soluble iron-containing compounds are promising iron fortificants. However, ensuring high bioaccessibility and low reactivity of iron is challenging. We present the potential application of ferrous pyrophosphate (Fe(II)PP) and Fe(II)-containing M2(1-x)Fe2x P2O7 salts (0 < x < 1, M = Ca, Zn, or Mn) for delivery of iron and a second essential mineral (M). After preparation by a facile and environment-friendly coprecipitation method, the salts were investigated for their composition, pH-dependent dissolution, iron-mediated discoloration of a black tea solution, and oxidation of vitamin C. Our results suggest that these salts are possible dual-fortificants with tunable composition that compared to Fe(II)PP (i) show lower (<0.5 mM) and enhanced (to 5 mM) iron dissolution in moderate and gastric pH, respectively, (ii) exhibit less discoloration and dissolved iron in tea when x = 0.470 for M = Ca or Zn and x = 0.086 for M = Mn, and (iii) do not increase the oxidation extent of vitamin C over 48 h when x = 0.06, 0.086, or 0.053 for M = Ca, Zn, or Mn, respectively.

Potentially functional lactose-free ice cream with Lacticaseibacillus casei CSL3, ginger, and honey

AIMS

To develop and characterize a functional lactose-free ice cream with added ginger and honey, evaluate the survival of Lacticaseibacillus casei CSL3 under frozen storage and the simulated gastrointestinal tract (GIT), as well as antioxidant activity and product acceptability.

METHODS AND RESULTS

The survival of Lacticaseibacillus casei CSL3 was evaluated for 180 days, under frozen storage, and GIT at 60 days. At 15 days of storage, proximal composition, antioxidant activity, color, pH, acidity, fusion, density, overrun, and sensory analysis were performed. Ice cream was an effective food matrix for maintaining the viability of CSL3, with concentrations > 7 log CFU g- 1 during storage and GIT. In addition, the analysis showed overrun and prebiotic characteristics through high values of antioxidant activity and phenolic compounds, good acceptability, and purchase intention.

CONCLUSIONS

The product has satisfactory market potential (acceptance rate of 95.19% and purchase intention rate > 96%), and it could become another means of inserting probiotics in food.

Crosstalk between dietary pomegranate and gut microbiota: evidence of health benefits

Gut microbiota (GM) is an invisible organ that plays an important role in human health. Increasing evidence suggests that polyphenols in pomegranate (punicalagin, PU) could serve as prebiotics to modulate the composition and function of GM. In turn, GM transform PU into bioactive metabolites such as ellagic acid (EA) and urolithin (Uro). In this review, the interplay between pomegranate and GM is thoroughly described by unveiling a dialog in which both actors seem to affect each other's roles. In a first dialog, the influence of bioactive compounds from pomegranate on GM is described. The second act shows how the GM biotransform pomegranate phenolics into Uro. Finally, the health benefits of Uro and that related molecular mechanism are summarized and discussed. Intake of pomegranate promotes beneficial bacteria in GM (e.g. Lactobacillus spp., Bifidobacterium spp.) while reducing the growth of harmful bacteria (e.g. Bacteroides fragilis group, Clostridia). Akkermansia muciniphila, and Gordonibacter spp., among others, biotransform PU and EA into Uro. Uro contributes to strengthening intestinal barrier and reducing inflammatory processes. Yet, Uro production varies greatly among individuals and depend on GM composition. Uro-producing bacteria and precise metabolic pathways need to be further elucidated therefore contributing to personalized and precision nutrition.

Boosting the Antioxidant Potential of Polymeric Proanthocyanidins in Litchi (Litchi chinensis Sonn.) Pericarp via Biotransformation of Utilizing Lactobacillus Plantarum

In order to enhance the efficient utilization of polymeric proanthocyanidins from litchi pericarp, a process for transforming litchis' polymeric proanthocyanidins (LPPCs) by using Lactobacilli has been established for products with highly antioxidative properties. Lactobacillus plantarum was selected to enhance the transformation effect. The transformation rate of LPPCs reached 78.36%. The content of litchis' oligomeric proanthocyanidins (LOPCs) in the products achieved 302.84 μg grape seed proanthocyanidins (GPS)/mg DW, while that of total phenols was 1077.93 gallic acid equivalents (GAE) μg/mg DW. Seven kinds of substances have been identified in the products by using the HPLC-QTOF-MS/MS method, among which 4-hydroxycinnamic acid, 3,4-dihydroxy-cinnamic acid, and proanthocyanidin A2 were major components. The in vitro antioxidative activity of the products after transformation was significantly (p < 0.05) higher than those of LOPCs and LPPCs. The scavenging activity of the transformed products for DPPH free radicals was 1.71 times that of LOPCs. The rate of inhibiting conjugated diene hydroperoxides (CD-POV) was 2.0 times that of LPPCs. The scavenging activity of the products for ABTS free radicals was 11.5 times that of LPPCs. The ORAC value of the products was 4.13 times that of LPPCs. In general, this study realizes the transformation of polymeric proanthocyanidins into high-activity small-molecule substances.

Stillage Waste from Strawberry Spirit Production as a Source of Bioactive Compounds with Antioxidant and Antiproliferative Potential

The production of fruit distillates generates solid residues which are potentially rich in bioactive compounds worthy of valorization and exploitation. We report herein the in vitro antioxidant and antiproliferative properties of an extract obtained from the waste of fermented strawberry distillate production. The main low molecular weight phenolic components of the extract were identified as ellagic acid and p-coumaric acid using spectroscopic and chromatographic analysis. The extract exhibited high antioxidant properties, particularly in the ferric reducing/antioxidant power (FRAP) assay, and a high total phenolic content (TPC). It was also able to induce an antiproliferative effect on different human cancer cell lines. A strong decrease in viability in human promyelocytic leukemia (HL-60) cells through a rapid and massive apoptosis were observed. Moreover, at an early time (<30 min), reactive oxygen species (ROS) production and inactivation of the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinases (MAPK) pathway were detected. Notably, the antiproliferative activity of the sample was comparable to that observed with an analogous extract prepared from unfermented, fresh strawberries. These results bring new opportunities for the valorization of fruit distillery by-products as low-cost resources for the design of bioactive formulations of comparable value to that from fresh food.

Adsorption of heavy metal onto biomass-derived activated carbon: review

Due to the rapid development of the social economy and the massive increase in population, human beings continue to undertake processing, and commercial manufacturing activities of heavy metals, which has caused serious damage to the environment and human health. Heavy metals lead to serious environmental problems such as soil contamination and water pollution. Human health and the living environment are closely affected by the handling of heavy metals. Researchers must find several simple, economical and practical methods to adsorb heavy metals. Adsorption technology has been recognized as an efficient and economic strategy, exhibiting the advantages of recovering and reusing adsorbents. Biomass-derived activated carbon adsorbents offer large adjustable specific surface area, hierarchically porous structure, strong adsorption capacity, and excellent high economic applicability. This paper focuses on reviewing the preparation methods of biomass-derived activated carbon in the past five years. The application of representative biomass-derived activated carbon in the adsorption of heavy metals preferentially was described to optimize the critical parameters of the activation type of samples and process conditions. The key factors of the adsorbent, the physicochemical properties of the heavy metals, and the adsorption conditions affecting the adsorption of heavy metals are highlighted. In addition, the challenges faced by biomass-derived activated carbon are also discussed.

Gallic acid ameliorates atherosclerosis and vascular senescence and remodels the microbiome in a sex-dependent manner in ApoE-/- mice

Polyphenols found in fruits and vegetables are associated with a reduced incidence of cardiovascular disease (CVD), the leading cause of death in the USA. Our lab demonstrated that blackberry supplementation reduces atherosclerosis in male, but not in female mice. The current study investigates whether gallic acid (GA), a polyphenol abundant in blackberry, decreases plaque and whether its effect is also sex-dependent. In vitro work using vascular smooth muscle cells (VSMCs) demonstrated that GA reduced cell signaling associated with proliferation, migration, and senescence. ApoE^-/- male and female mice were treated with and without 0.2% GA in drinking water and fed a chow diet (2 weeks), then switched to high-fat diet (HFD) (5 weeks) with the same GA regimen. Similar to the blackberry study, GA reduced atherosclerosis only in males. This GA-induced plaque reduction was independent of plasma cholesterol, triglycerides (TG), LDL, or HDL but corresponded with indices of lower inflammation. Males showed reduced spleen weight and serum IL3 and IL12 levels, and gut health improvement. In females, GA increased anti-atherogenic (HDL and IL10) molecules, while upregulating several pro-inflammatory cytokines and chemokines, including tumor necrosis factor α (TNFα). A major sex-dependent effect of GA was the almost complete disappearance of Eubacterium fissicatena and Turicibacter induced by HFD in males, a finding not seen in females. This study provides novel insights into how GA can improve gut microbiota alterations associated with CVD and suggests that males suffering from atherosclerosis may benefit from GA supplementation, as this polyphenol partially restored microbiome dysbiosis.

Metabolomic Profiling and Assessment of Phenolic Compounds Derived from Vitis davidii Foex Cane and Stem Extracts

Phenolic extracts from berry seeds have been extensively studied for their health benefits. However, few studies have been conducted on the effects of phenolic extracts from Vitis L. canes and berry stems. The Chinese spine grape (V. davidii Foex) is an important and widely distributed wild species of Vitis L. The present study explored the metabolomic profile and evaluated the antioxidant activity of phenolic compounds in extracts from V. davidii Foex. canes and stems, with a focus on their role in preventing DNA damage caused by free radicals and inhibiting the growth of breast (MCF-7) and cervical (HeLa) cancer cells. Total phenolic compounds in the dried berry stems of spine grapes were higher than that in vine canes. Analysis of the extracts showed that proanthocyanins, epicatechin, catechin, and phenolic acid were the main phenolic compounds in V. davidii Foex, but in higher quantities in berry stems than in vine canes. However, trans-resveratrol and kaempferol 3-O-glucoside were present in the vine canes but not in the berry stems. Antioxidant analysis by FRAP and ABTS showed that extracts from berry stems and vine canes had a higher antioxidant activity than thinned young fruit shoots before flowering, leaves, peel, pulp, and seeds in V. davidii Foex. Moreover, the antioxidant activity of extracts from berry stems was higher than that in other grape species, except for muscadine. In vitro analyses further showed that the extracts significantly increased H₂O₂ scavenging ability and conferred a protective effect against DNA damage. Furthermore, a low concentration of phenolic compounds in extracts from the vine canes and berry stems of spine grapes inhibited the proliferation of the MCF-7 and Hela cancer cells. These research results provided some important useful information for the exploitation of V. davidii Foex canes and berry stems and indicated that canes and stems of V. davidii Foex had good antioxidant properties, anticancer activity and prevented DNA damage, providing evidence for medical utilization of V. davidii Foex.

Effects of Dietary Tannic Acid on Obesity and Gut Microbiota in C57BL/6J Mice Fed with High-Fat Diet

Dietary tannic acid, as a natural polyphenolic, has many important biological activities. This study aimed to investigate the effect of dietary tannic acid on obesity and gut microbiota in mice with a high-fat diet. Male C57BL/6J mice fed a high-fat diet were treated with dietary tannic acid for eight weeks. Results showed that dietary tannic acid reduced the body weight gain, regulated glycolipid metabolism, improved the insulin resistance, and attenuated the liver oxidative stress in high-fat diet-fed mice. Moreover, both dietary tannic acid intervention groups repaired the gut barrier damage caused by a high-fat diet, especially in the 50 mg/kg/d dietary tannic acid intervention group. Interestingly, the effect of dietary tannic acid on serum endotoxin lipopolysaccharide (LPS) content was correlated with the abundance of the LPS-producing microbiota. In addition, dietary tannic acid altered the abundance of obesity-related gut microbiota (Firmicutes, Bacteroidetes, Bacteroides, Alistipes, and Odoribacter) in the 150 mg/kg/d dietary tannic acid intervention group, while it was not effective in the 50 mg/kg/d dietary tannic acid intervention group. These findings suggested the potential effect of dietary tannic acid for the prevention and control of obesity.

Polyphenols as Plant-Based Nutraceuticals: Health Effects, Encapsulation, Nano-Delivery, and Application

Plant polyphenols have attracted considerable attention because of their key roles in preventing many diseases, including high blood sugar, high cholesterol, and cancer. A variety of functional foods have been designed and developed with plant polyphenols as the main active ingredients. Polyphenols mainly come from vegetables and fruits and can generally be divided according to their structure into flavonoids, astragalus, phenolic acids, and lignans. Polyphenols are a group of plant-derived functional food ingredients with different molecular structures and various biological activities including antioxidant, anti-inflammatory, and anticancer properties. However, many polyphenolic compounds have low oral bioavailability, which limits the application of polyphenols in nutraceuticals. Fortunately, green bio-based nanocarriers are well suited for encapsulating, protecting, and delivering polyphenols, thereby improving their bioavailability. In this paper, the health benefits of plant polyphenols in the prevention of various diseases are summarized, with a review of the research progress into bio-based nanocarriers for the improvement of the oral bioavailability of polyphenols. Polyphenols have great potential for application as key formulations in health and nutrition products. In the future, the development of food-grade delivery carriers for the encapsulation and delivery of polyphenolic compounds could well solve the limitations of poor water solubility and low bioavailability of polyphenols for practical applications.

Regulatory Effect of Sea-Buckthorn Procyanidins on Oxidative Injury HUVECs

As society develops and aging populations increase, the incidence of arteriosclerosis, a seriously harmful cardiovascular disease (CVD) which mostly results from endothelial cellular oxidative damage, has continuously risen. Procyanidins from sea-buckthorn is a powerful antioxidant, although its protective effect on the cardiovascular system is not yet clearly understand. In this study, oxidative damaged HUVECs induced by palmitate acid (PA) were used as a model and the regulatory effect of procyanidins from sea-buckthorn (SBP) on HUVECs were investigated. The results showed SBP can be used for 12 h by HUVECs and had no detective cytotoxicity to them under 400 μg/L. Also, different concentrations of SBP can increase mitochondrial membrane potential and NO level and decrease LDH leakage in a dose-effect relationship, indicating SBP can improve oxidative damage. In addition, western blots and qPCR results showed SBP regulation on oxidative injured HUVECs is probably through p38MAPK/NF-κB signal pathway. This study revealed the molecular mechanism of procyanidins in decreasing endothelial oxidative damage, providing a theoretical foundation for further research on natural bioactive compounds to exert antioxidant activity in the body and prevent and improve cardiovascular diseases.

Moringa oleifera Seed at the Interface of Food and Medicine: Effect of Extracts on Some Reproductive Parameters, Hepatic and Renal Histology

The lipid-rich Seed of Moringa oleifera has been promoted as an effective water clarifier. Aside its vital nutritional application as an emerging food additive, the seed has continued to gain a wider acceptance in various global ethnomedicines for managing several communicable and lifestyle diseases, howbeit, its potential toxic effect, particularly on fertility and pregnancy outcomes has remained uninvestigated; the effect of Moringa oleifera seed (MOSE) aqueous-methanol extracts on fertility and pregnancy outcome, was investigated in vivo using female Wistar rats that were divided into 50, 100, 300 and 500 mg per kilogram body weight. Group six was given Moringa oleifera seed treated water ad-libitum (ad-libitum group). Organs harvested for histological assessment included ovary, uterus, liver and kidney. In addition to HPLC fingerprint and a preliminary peptide detection, we determined the physico-chemical characteristics and mineral content of MOSE using standard methods. Data were analyzed with significance at p ≤ 0.05. There was no significant difference in the estrus cycle, mating index, gestation survival index, gestation index, fertility index and sex ratio among all groups. Gestation length was reduced in some groups. While the male pup birth weight was comparable among the different groups, female pups birth weights were significantly reduced in 50 and 100 mg groups. Anogenital distance indices of female pups in ad libitum group were significantly increased. Pathologies were observed in liver and kidneys of dams while kidneys of pups presented a dose dependent reduction in the number of glomeruli. There were no observed pathological changes in the ovary and uterus. This study showed for the first time in rodents, that the lipid-rich MOSE is unsafe to the kidney of rodents while the lipid-free MOSE appears to be safe at doses up to 300 mg/kg body weight. Findings from this study suggested that the female pups were masculinized. In conclusion, the lipid-rich seed extracts of MOSE appear to be unsafe during pregnancy, induce hepatic and renal toxicity while the lipid-free MOSE excludes inherent toxicity as the hydrophobic part has been linked to toxicity as observed in this study due to the developmental programming effect on female offspring in rodents.

Plant-Based Polyphenols: Anti-Helicobacter pylori Effect and Improvement of Gut Microbiota

Helicobacter pylori (H. pylori) infection affects more than half of the world’s population, and thus, about 10 to 20% of people with H. pylori suffer from peptic ulcers, which may ultimately lead to gastric cancer. The increase in antibiotic resistance and susceptibility has encouraged the search for new alternative therapies to eradicate this pathogen. Several plant species are essential sources of polyphenols, and these bioactive compounds have demonstrated health-promoting properties, such as the gut microbiota stimulation, inflammation reduction, and bactericidal effect. Therefore, this review aims to discuss the potential effect of plant-based polyphenols against H. pylori and their role in the gut microbiota improvement.

Composition analysis and antioxidant activity evaluation of a high purity oligomeric procyanidin prepared from sea buckthorn by a green method

Procyanidin is an important polyphenol for its health-promoting properties, however, the study of procyanidin in sea buckthorn was limited. In this paper, sea buckthorn procyanidin (SBP) was obtained through a green isolation and enrichment technique with an extraction rate and purity of 9.1% and 91.5%. The structure of SBP was analyzed using Ultraviolet–visible spectroscopy (UV–vis), Fourier-transform infrared spectroscopy (FT-IR), and liquid chromatography-mass spectrometry (LC-MS/MS). The results show that SBP is an oligomeric procyanidin, mainly composed of (−)-epicatechin gallate, procyanidin B, (+)-gallocatechin-(+)-catechin, and (+)-gallocatechin dimer. SBP showed superior scavenging capacity on free radicals. Furthermore, the cleaning rate of the ABTS radical was 4.8 times higher than vitamin C at the same concentration. Moreover, SBP combined with vitamin C presented potent synergistic antioxidants with combined index values below 0.3 with concentration rates from 5:5 to 2:8. SBP also provided significant protection against oxidative stress caused by hydrogen peroxide (H₂O₂) on RAW264.7 cells. These findings prove the potential of SBP as a natural antioxidant in food additives and support the in-depth development of sea buckthorn resources.

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A green method for the extraction of procyanidin was proposed.

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An oligomeric procyanidin in sea buckthorn was identified for the first time.

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SBP combined with VC exerted strong synergistic antioxidant.

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SBP provided protection of macrophages against oxidative damage.