Polyphenols from Olive-Mill Wastewater and Biological Activity: Focus on Irritable Bowel Syndrome

Lentil Waste Extracts for Inflammatory Bowel Disease (IBD) Symptoms Control: Anti-Inflammatory and Spasmolytic Effects

BACKGROUND/OBJECTIVES

In the contest of agro-industrial waste valorization, we focused our attention on lentil seed coats as a source of health-promoting phytochemicals possibly useful in managing inflammatory bowel diseases (IBDs), usually characterized by inflammation and altered intestinal motility.

METHODS

Both traditional (maceration) and innovative microwave-assisted extractions were performed using green solvents, and the anti-inflammatory and spasmolytic activities of the so-obtained extracts were determined through in vitro and ex vivo assays, respectively.

RESULTS

The extract obtained through the microwave-assisted procedure using ethyl acetate as the extraction solvent (BEVa) proved to be the most useful in inflammation and intestinal motility management. In LPS-activated Caco-2 cells, BEVa down-regulated TLR4 expression, reduced iNOS expression and the pro-inflammatory cytokine IL-1 production, and upregulated the anti-inflammatory cytokine IL-10 production, thus positively affecting cell inflammatory responses. Moreover, a significant decrease in the longitudinal and circular tones of the guinea pig ileum, with a reduction of transit speed and pain at the ileum level, together with reduced transit speed, pain, and muscular tone at the colon level, was observed with BEVa. HPLC separation combined with an Orbitrap-based high-resolution mass spectrometry (HRMS) technique indicated that 7% of all the identified metabolites were endowed with proven anti-inflammatory and antispasmodic activities, among which niacinamide, apocynin, and p-coumaric acid were the most abundant.

CONCLUSIONS

Our results suggest that lentil hull extract consumption could contribute to overall intestinal health maintenance, with BEVa possibly representing a dietary supplementation and a promising approach to treating intestinal barrier dysfunction.

Systematic screening for the biocatalytic hydration of fatty acids from different oily substrates by Elizabethkingia meningoseptica oleate hydratase through a Design-of-experiments approach

The edible plant oils production is associated with the release of different types of by-products. The latter represent cheap and available substrates to produce valuable compounds, such as flavours and fragrances, biologically active compounds and bio-based polymers. Elizabethkingia meningoseptica Oleate hydratases (Em_OhyA) can selectively catalyze the conversion of unsaturated fatty acids, specifically oleic acid, into hydroxy fatty acids, which find different industrial applications. In this study, Design-of-experiment (DoE) strategy was used to screen and identify conditions for reaching high yields in the reaction carried out by Escherichia coli whole-cell carrying the recombinant enzyme Em_OhyA using Waste Cooking Oils (WCO)-derived free fatty acids (FFA) as substrate. The identified reaction conditions for high oleic acid conversion were also tested on untreated triglycerides-containing substrates, such as pomace oil, sunflower oil, olive oil and oil mill wastewater (OMW), combining the triglyceride hydrolysis by the lipase from Candida rugosa and the E. coli whole-cell containing Em_OhyA for the production of hydroxy fatty acids. When WCO, sunflower oil and OMW were used as substrate, the one-pot bioconversion led to an increase of oleic acid conversion compared to the standard reaction. This work highlights the efficiency of the DoE approach to screen and identify conditions for an enzymatic reaction for the production of industrially-relevant products.

From Waste to Health: Olive Mill Wastewater for Cardiovascular Disease Prevention

Waste from the agri-food chain represents a valuable reservoir of organic compounds with health-promoting properties. Momast Plus 30 Bio (MP30B) is a derivative obtained from olive-oil wastewater. Its enrichment in hydroxytyrosol (HT) via a patented technique has paved the way for its potential application as a dietary supplement in preventing cardiovascular diseases. MP30B demonstrates no significant alteration in cardiac and vascular parameters in "ex vivo" studies. However, it exhibits a strong ability to remove reactive oxygen species and exerts anti-inflammatory effects, notably reducing the concentration of iNOS and mitigating heart infections in "in vitro" experiments. Furthermore, MP30B slightly decreases the stiffness of the "ex vivo" thoracic aorta, potentially resulting in lowered arterial pressure and enhanced energy transfer to a normal ventricle. Based on these findings, we posit MP30B as a promising extract for cardiovascular disease prevention, and its specific antibacterial properties suggest its utility in preventing cardiac infections.

Preventive effects of a nutraceutical mixture of berberine, citrus and apple extracts on metabolic disturbances in Zucker fatty rats

BACKGROUND

The prevention of obesity represents a major health and socio-economic challenge. Nutraceuticals are regularly highlighted for their beneficial effects in preventing the metabolic disturbances associated with obesity. However, few studies have described the combined action of nutraceutical mixtures combining polyphenols with alkaloids.

OBJECTIVE

The aim of this study was to evaluate the effects of long-term dietary supplementation with a mixture of Berberine, Citrus and Apple extracts (BCA) in the primary prevention of obesity and its metabolic and vascular complications in the obese Zucker rat, a spontaneous model of genetic obesity and insulin resistance.

METHODS

Sixteen 8-week-old obese Zucker male rats were randomly divided into two groups: all rats received oral gavage daily either with water, untreated obese (U-ObZ) or BCA (BCA-ObZ) mixture for thirteen weeks. Morphological and metabolic parameters were measured along the study. Cumulative concentration-response curves to insulin, acetylcholine and phenylephrine were determined on isolated thoracic aorta. Colon permeability measurements were performed using the Ussing chamber technique. Fecal samples collected at the beginning and the end of the protocol were used as a template for amplification of the V3-V4 region of the 16S rDNA genes.

RESULTS

BCA supplementation reduced weight gain (p<0.05) and food intake (p<0.05) in the BCA-ObZ group rats compared to the U-ObZ group rats. It also improved glucose tolerance (p<0.001) and decreased fasting insulin and Homeostasis model assessment index (p<0.05). Through ex vivo experiments, the BCA mixture enhanced significantly aortic insulin relaxation (p<0.01), reduced α1-adrenoceptor-mediated vasoconstriction (p<0.01), and decreased distal colon permeability. Moreover, short-chain fatty acid producers such as Bacteroides, Blautia, and Akkermansia were found to be increased by the BCA mixture supplementation.

CONCLUSION

The results showed that a 13-week-supplementation with BCA mixture prevented weight gain and improved glucose metabolism in obese Zucker rats. We also demonstrated that BCA supplementation improved vascular function, colonic barrier permeability and gut microbiota profile.

Enhancement of the biological activity of hydroxytyrosol through its oxidation by laccase from Trametes versicolor

The laccase-catalyzed oxidation of hydroxytyrosol (HT) towards the formation of its bioactive oligomer derivatives was investigated. The biocatalytic oligomerization was catalyzed by laccase from Trametes versicolor in aqueous or various water-miscible organic solvents and deep eutectic solvent (DES)-based media. Mass Spectroscopy and Nuclear Magnetic Resonance were used for the characterization of the products. The solvent system used significantly affects the degree of HT oligomerization. The use of 50 % v/v methanol favored the production of the HT dimer, while other organic solvents as well as DESs led to the formation of hydroxytyrosol trimer and other oligomers. In vitro studies showed that the HT dimer exhibits 3- to 4-fold enhanced antibacterial activity against Gram-positive and Gram-negative bacteria compared to the parent compound. Moreover, the ability of HT dimer to inhibit the activity of soybean lipoxygenase and Candida rugosa lipase was 1.5-fold higher than HT, while molecular docking supported these results. Furthermore, HT dimer showed reduced cytotoxicity against HEK293 cells and exhibited a strong ability to inhibit ROS formation. The enhanced bioactivity of HT dimer indicates that this compound could be considered for use in cosmetics, skin-care products, and nutraceuticals.

Development and Validation of a High-Performance Liquid Chromatography Method to Quantify Marker Compounds in Lysimachia vulgaris var. davurica and Its Effects in Diarrhea-Predominant Irritable Bowel Syndrome

Irritable bowel syndrome (IBS), a common gastrointestinal disorder worldwide, is characterized by chronic abdominal pain, bloating, and disordered defecation. IBS is associated with several factors, including visceral hypersensitivity, gut motility, and gut-brain interaction disorders. Because currently available pharmacological treatments cannot adequately improve symptoms and may cause adverse effects, the use of herbal therapies for managing IBS is increasing. Lysimachia vulgaris var. davurica (LV) is a medicinal plant used in traditional medicine to treat diarrhea. However, information on whether LV can effectively improve diarrhea-predominant IBS (IBS-D) remains limited. In this study, using an experimental mouse model of IBS-D, we elucidated the effects of the LV extract. The methanol extract of LV decreased fecal pellet output in the restraint stress- or 5-hydroxytryptamine (5-HT)-induced IBS mouse model and inhibited 5-HT-mediated [Ca2+]i increase in a dose-dependent manner. Furthermore, we developed and validated a high-performance liquid chromatography method using two marker compounds, namely, chlorogenic acid and rutin, for quality control analysis. Our study results suggest the feasibility of the methanol extract of LV for developing therapeutic agents to treat IBS-D by acting as a 5-HT3 receptor antagonist.

Dietary Polyphenols and Their Role in Gut Health

Polyphenols are secondary plant metabolites derived from the shikimate/phenylpropanoid pathway, protecting plants from physical, chemical and biological stress [...].