Enzyme-assisted extraction of phenolics from winemaking by-products: Antioxidant potential and inhibition of alpha-glucosidase and lipase activities

Latest Advances in Green Extraction of Polyphenols from Plants, Foods and Food By-Products

Phenolic compounds present in plants and foods are receiving increasing attention for their bioactive and sensory properties, accompanied by consumers' interest in products with health benefits derived from natural rather than artificial sources. This, together with the sustainable development goals for the 21st century, has driven the development of green extraction techniques that allow obtaining these compounds with the safety and quality required to be applied in the food, cosmetic and pharmaceutical industries. Green extraction of natural products involves practices aiming at reducing the environmental impact of the preparation processes, based on using natural or less-polluting solvents, lower energetic requirements and shorter extraction times, while providing greater efficiency in the recovery of target compounds. In this article, the principles of sustainable extraction techniques and the advances produced in recent years regarding green isolation of polyphenols from plants, food and food waste are reviewed.

Phenolic Fractions from Walnut Milk Residue: Antioxidant Activity and Cytotoxic Potential

Walnut milk residues (WMR) were investigated for the first time through their phenolic characterization including soluble (free, esterified, and etherified) phenolics and those released from their insoluble-bound form (insoluble-bound phenolic hydrolysates, IBPHs) and their antioxidant properties. Free phenolics were recovered and alkaline or acid hydrolysis were used to recover the remaining phenolic fractions. Total phenolic compounds (TPCs) and their antioxidant activity were analyzed by Folin-Ciocalteu, FRAP, and ORAC methods, respectively. Soluble phenolics (free + esterified + etherified fractions) showed a higher TPC (275.3 mg GAE 100 g-1 dw) and antioxidant activity (FRAP: 138.13 µmol TE g-1 dw; ORAC: 45.41 µmol TE g-1 dw) with respect to the IBPH. There was a significant correlation between TPC and FRAP and ORAC values regardless of the fraction and tested sample. Phenolic acids and flavonoids were identified and quantified by ultra-performance liquid chromatography-electrospray tandem mass spectrometry (UPLC-ESI-MS/MS). Gallic acid, mainly in the free form (3061.0 µg 100 g-1), was the most representative, followed by biochanin A, identified for the first time in a walnut product and mostly present in the fraction released from the esterified form (593.75 µg 100 g-1). No detrimental cytotoxic impact on Caco-2 cells was observed. Hence, WMR could be considered a potential source for the development of nutraceutical and/or antioxidant food additives.

Insights into grape-derived health benefits: a comprehensive overview

Grapes, renowned for their diverse phytochemical composition, have long been recognized for their health-promoting properties. This narrative review aims to synthesize the current research on grapes, with a particular emphasis on their role in disease prevention and health enhancement through bioactive compounds.

A comprehensive review of peer-reviewed studies, including in vitro, in vivo, and clinical investigations, was conducted to elucidate the relationship between grape consumption and health outcomes. The review highlights the positive association of grape intake with a decreased risk of chronic diseases such as cardiovascular disease, type 2 diabetes, and certain cancers. Notable bioactive components like resveratrol are emphasized for their neuroprotective and antioxidative capabilities. Additionally, the review explores emerging research on the impact of grapes on gut microbiota and its implications for metabolic health and immune function.

This updated review underscores the importance of future research to fully leverage and understand the therapeutic potential of grape-derived compounds, aiming to refine dietary guidelines and functional food formulations. Further translational studies are expected to clarify the specific bioactive interactions and their impacts on health.

Graphical Abstract

Polyphenol compounds contributing to the improved bioactivities of fermented Rubus chingii Hu

This research aims to evaluate the phenolic composition, antioxidant and enzyme inhibition activities of fermented Rubus chingii Hu wine, and explore the correlation between them. TPC (Total Phenolic content) and TFC (Total Flavonoid content) increased rapidly from 0 h to 72 h, followed by a slight decrease in TPC and a significant decrease in TFC. Fermentation could significantly increase the antioxidant activity and α-amylase/α-glucosidase enzyme inhibitory activity of Rubus chingii Hu. A total of 39 polyphenols and organic acids in fermented Rubus chingii Hu were identified by UPLC-ESI-Q-TOF-MS/MS and 11 of them were quantitatively analyzed. After fermentation, the contents of all the detected polyphenol compounds, except for quercetin and ellagic acid, significantly increased (p < 0.05). Correlation analysis showed that protocatechuic acid and catechin played an important role in the antioxidant activity of fermented Rubus chingii Hu, while protocatechuic acid and hypericin played an important role in the α-amylase inhibition activity. This study indicated that Rubus chingii Hu could be applided as a potential meterial for the wine production, and has the potential to be a functional food for promoting health.

The Potential Health Benefits of Gallic Acid: Therapeutic and Food Applications

Gallic acid (GA), a phenolic acid found in fruits and vegetables, has been consumed by humans for centuries. Its extensive health benefits, such as antimicrobial, antioxidant, anticancer, anti-inflammatory, and antiviral properties, have been well-documented. GA's potent antioxidant capabilities enable it to neutralize free radicals, reduce oxidative stress, and protect cells from damage. Additionally, GA exerts anti-inflammatory effects by inhibiting inflammatory cytokines and enzymes, making it a potential therapeutic agent for inflammatory diseases. It also demonstrates anticancer properties by inhibiting cancer cell growth and promoting apoptosis. Furthermore, GA offers cardiovascular benefits, such as lowering blood pressure, decreasing cholesterol, and enhancing endothelial function, which may aid in the prevention and management of cardiovascular diseases. This review covers the chemical structure, sources, identification and quantification methods, and biological and therapeutic properties of GA, along with its applications in food. As research progresses, the future for GA appears promising, with potential uses in functional foods, pharmaceuticals, and nutraceuticals aimed at improving overall health and preventing disease. However, ongoing research and innovation are necessary to fully understand its functional benefits, address current challenges, and establish GA as a mainstay in therapeutic and nutritional interventions.

In Vitro Gastrointestinal Digestion of Various Sweet Potato Leaves: Polyphenol Profiles, Bioaccessibility and Bioavailability Elucidation

The chemical composition discrepancies of five sweet potato leaves (SPLs) and their phenolic profile variations during in vitro digestion were investigated. The results indicated that Ecaishu No. 10 (EC10) provided better retention capacity for phenolic compounds after drying. Furthermore, polyphenols were progressively released from the matrix as the digestion process proceeded. The highest bioaccessibility of polyphenols was found in EC10 intestinal chyme at 48.47%. For its phenolic profile, 3-, 4-, and 5-monosubstituted caffeoyl quinic acids were 9.75%, 57.39%, and 79.37%, respectively, while 3,4-, 3,5-, and 4,5-disubstituted caffeoyl quinic acids were 6.55, 0.27 and 13.18%, respectively. In contrast, the 3,4-, 3,5-, 4,5-disubstituted caffeoylquinic acid in the intestinal fluid after dialysis bag treatment was 62.12%, 79.12%, and 62.98%, respectively, which resulted in relatively enhanced bioactivities (DPPH, 10.51 μmol Trolox/g; FRAP, 8.89 μmol Trolox/g; ORAC, 7.32 μmol Trolox/g; IC50 for α-amylase, 19.36 mg/g; IC50 for α-glucosidase, 25.21 mg/g). In summary, desirable phenolic acid release characteristics and bioactivity of EC10 were observed in this study, indicating that it has potential as a functional food ingredient, which is conducive to the exploitation of the sweet potato processing industry from a long-term perspective.

Improving Soluble Phenolic Profile and Antioxidant Activity of Grape Pomace Seeds through Fungal Solid-State Fermentation

Grape pomace seeds contain abundant phenolic compounds, which are also present in both soluble and insoluble forms, similar to many other plant matrices. To further increase the extractable soluble phenolics and their antioxidant activities, grape pomace seeds were fermented with different fungi. Results showed that solid-state fermentation (SSF) with Aspergillus niger, Monascus anka, and Eurotium cristatum at 28 °C and 65% humidity had a significantly positive impact on the release of soluble phenolics in grape pomace seeds. Specifically, SSF with M. anka increased the soluble phenolic contents by 6.42 times (calculated as total phenolic content) and 6.68 times (calculated as total flavonoid content), leading to an overall improvement of antioxidant activities, including DPPH (increased by 2.14 times) and ABTS (increased by 3.64 times) radical scavenging activity. Furthermore, substantial changes were observed in the composition and content of individual phenolic compounds in the soluble fraction, with significantly heightened levels of specific phenolics such as chlorogenic acid, syringic acid, ferulic acid, epicatechin gallate, and resveratrol. Notably, during M. anka SSF, positive correlations were identified between the soluble phenolic content and hydrolase activities. In particular, there is a strong positive correlation between glycosidase and soluble phenols (r = 0.900). The findings present an effective strategy for improving the soluble phenolic profiles and bioactivities of grape pomace seeds through fungal SSF, thereby facilitating the valorization of winemaking by-products.

Nutraceutical Potential of Underutilized Tropical Fruits and Their Byproducts: Phenolic Profile, Antioxidant Capacity, and Biological Activity of Jerivá (Syagrus romanzoffiana) and Butiá (Butia catarinensis)

Jerivá and butiá are under-valued tropical fruits lacking scientific evidence about their nutraceutical potential. Therefore, they were investigated for their phenolic compound composition and biological activities. Free, esterified, and insoluble-bound polyphenols were obtained from powdered jerivá and butiá pomace and seeds. The total phenolic estimation in seeds (jerivá, 36.45 mg GAE/g; butiá, 45.79 mg GAE/g) exceeded pomaces (jerivá, 23.77 mg GAE/g; butiá, 18.69 mg GAE/g). Phenolic extracts demonstrated antidiabetic and antiobesity potential, inhibiting α-glucosidase (30.51-98.43%) and pancreatic lipase (19.66-41.98%). They also suppressed free radical-induced damage to DNA (21.46-92.48%) and LDL-cholesterol (8.27-23.20%). Identified phenolics (51) included multiple phenolic acids, flavonoids, and tannins, predominantly gallic acid derivatives/conjugates. This is the first study to provide a detailed description of the phenolic profile of these fruits and their byproducts coupled with their bioactivities. Butiá and jerivá were demonstrated to be outstanding sources of polyphenols with high nutraceutical potential for bioeconomic exploration.

Beyond the Bottle: Exploring Health-Promoting Compounds in Wine and Wine-Related Products-Extraction, Detection, Quantification, Aroma Properties, and Terroir Effects

Health-promoting compounds in wine and wine-related products are important due to their potential benefits to human health. Through an extensive literature review, this study explores the presence of these compounds in wine and wine-related products, examining their relationship with terroir and their impact on the aromatic and flavor properties that are perceived orally: sunlight exposure, rainfall patterns, and soil composition impact grapevines' synthesis and accumulation of health-promoting compounds. Enzymes, pH, and the oral microbiome are crucial in sensory evaluation and perception of health promotion. Moreover, their analysis of health-promoting compounds in wine and wine-related products relies on considerations such as the specific target compound, selectivity, sensitivity, and the complexity of the matrix.

Influence of Enzymatic Hydrolysis on Composition and Technological Properties of Apple Pomace and Its Application for Wheat Bread Making

The aim of this work was to evaluate the influence of enzymatic hydrolysis on dietary fiber, phenolic compounds and technological properties of apple pomace as wheat bread supplement. Apple pomace was hydrolyzed with Viscozyme® L, Pectinex® Ultra Tropical, Celluclast® 1.5 L for 1 and 5 h. Soluble (SDF) and insoluble (IDF) dietary fiber, reducing sugars and the total phenolic contents (TPC), along with the technological properties (water and oil retention capacities, solubility index, emulsion stability) of treated apple pomace were evaluated. The prebiotic activity of apple pomace water-soluble fraction on two probiotic strains Lactobacillus acidophilus DSM 20079 and Bifidobacterium animalis DSM 20105 was investigated. Treatment with Celluclast® 1.5 L increased SDF, reducing sugars, SDF/IDF ratio and decreased IDF of apple pomace. While treatment with Viscozyme® L, Pectinex® Ultra Tropical increased reducing sugars, solubility index and TPC, but in most cases reduced oil and water retention capacities, decreased SDF and IDF content. All apple pomace extracts promoted growth of probiotic strains. Addition of 5% of apple pomace hydrolyzed with Celluclast® 1.5 L did not have negative impact on wheat bread, while addition of other enzymatically hydrolyzed apple pomaces decreased pH, specific volume and porosity of wheat bread. Obtained results suggest that apple pomace enzymatically hydrolyzed with Celluclast® 1.5 L can be potentially used for wheat bread supplementation with dietary fiber.

Importance of Insoluble-Bound Phenolics to the Antioxidant Potential Is Dictated by Source Material

Insoluble-bound phenolics (IBPs) are extensively found in the cell wall and distributed in various tissues/organs of plants, mainly cereals, legumes, and pulses. In particular, IBPs are mainly distributed in the protective tissues, such as seed coat, pericarp, and hull, and are also available in nutritional tissues, including germ, epicotyl, hypocotyl radicle, and endosperm, among others. IBPs account for 20-60% of the total phenolics in food matrices and can exceed 70% in leaves, flowers, peels, pulps, seeds, and other counterparts of fruits and vegetables, and up to 99% in cereal brans. These phenolics are mostly covalently bound to various macromolecules such as hemicellulose, cellulose, structural protein, arabinoxylan, and pectin, which can be extracted by acid, alkali, or enzymatic hydrolysis along with various thermal and non-thermal treatments. IBPs obtained from various sources exhibited a wide range of biological activities, including antioxidant, anti-inflammatory, antihypertensive, anticancer, anti-obesity, and anti-diabetic properties. In this contribution, the chemistry, distribution, biological activities, metabolism, and extraction methods of IBPs, and how they are affected by various treatments, are summarized. In particular, the effect of thermal and non-thermal processing on the release of IBPs and their antioxidant potential is discussed.

Bioaccessibility of phenolic compounds using the standardized INFOGEST protocol: A narrative review

The INFOGEST protocol creation was a watershed for phenolic bioaccessibility studies. Because of this important initiative to standardize bioaccessibility studies, data comparisons between different laboratories are now expedited. It has been eight years since the INFOGEST protocol creation, and three from the latest update. However, the current status in terms of phenolic bioaccessibility and how far different laboratories are from reaching a consensus are still unrevealed. In this sense, this narrative review considered an evaluation of different studies that applied the INFOGEST protocol to investigate the bioaccessibility of phenolic compounds. The central objective was to compile the main findings and consensus and to identify possible gaps and future opportunities. This approach intends to further facilitate the use of this protocol by professionals in the field of food science and technology and related areas, generating a reflection on the actual level of standardization of the method. Despite the differences in phenolic compounds from diverse food matrices, and their peculiar behavior, some trends could be elucidated, in terms of phenolic release, stability, and/or transformation upon in vivo digestion. In contrast, there was no general consensus regarding sample preparation, how to report results and the form to calculate bioaccessibility, making it difficult to compare different studies. There is still a long road to effectively standardize the results obtained for phenolic bioaccessibility using the INFOGEST protocol, which is also an opportunity in terms of food analysis that can impact the food industry, especially for the development of nutraceuticals and functional foods.

Selection of Enzymatic Treatments for Upcycling Lentil Hulls into Ingredients Rich in Oligosaccharides and Free Phenolics

In this study, the comprehensive chemical characterization of red lentil hulls obtained from the industrial production of football and split lentils was described. The lentil hulls were rich in dietary fiber (78.43 g/100 g dry weight with an insoluble to soluble fiber ratio of 4:1) and polyphenols (49.3 mg GAE/g dry weight, of which 55% was bound phenolics), which revealed the suitability of this lentil by-product as a source of bioactive compounds with recognized antioxidant and prebiotic properties. The release of oligosaccharides and phenolic compounds was accomplished by enzymatic hydrolysis, microwave treatment and a combination of both technologies. The key role played by the selection of a suitable enzymatic preparation was highlighted to maximize the yield of bioactive compounds and the functional properties of the lentil hull hydrolysates. Out of seven commercial preparations, the one with the most potential for use in a commercial context was Pectinex^® Ultra Tropical, which produced the highest yields of oligosaccharides (14 g/100 g lentil hull weight) and free phenolics (45.5 mg GAE/100 g lentil hull weight) and delivered a four-fold increase in terms of the original antioxidant activity. Finally, this enzyme was selected to analyze the effect of a microwave-assisted extraction pretreatment on the yield of enzymatic hydrolysis and the content of free phenolic compounds and oligosaccharides. The integrated microwave and enzymatic hydrolysis method, although it increased the solubilization yield of the lentil hulls (from 25% to 34%), it slightly decreased the content of oligosaccharides and proanthocyanidins and reduced the antioxidant activity. Therefore, the enzymatic hydrolysis treatment alone was more suitable for producing a lentil hull hydrolysate enriched in potential prebiotics and antioxidant compounds.

The recovery from agro-industrial wastes provides different profiles of anti-inflammatory polyphenols for tailored applications

Food and agro-industrial processing produce a great amount of side-stream and waste materials that are excellent sources of functional bioactive molecules such as phenolic compounds that recover them can be beneficial not only for food sustainability but also to human for many industrial applications such as flavor compounds and therapeutic applications such as antimicrobial and anti-inflammatory. The treatments and extraction techniques have major effects on the recovery of bioactive compounds. Along with the conventional extraction methods, numerous innovative techniques have been evolved and have been optimized to facilitate bioactive extraction more efficiently and sustainably. In this work, we have summarized the state-of-the-art technological approaches concerning novel extraction methods applied for five most produced crops in Italy; Grape Pomace (GP), Tomato Pomace (TP), Olive Pomace (OP), Citrus Pomace (CP), and Spent Coffee Grounds (SCG), presenting the extraction yield and the main class of phenolic classes, with the focus on their biological activity as an anti-inflammatory in vitro and in vivo studies via describing their molecular mechanism of action.

An Overview on the Use of Extracts from Medicinal and Aromatic Plants to Improve Nutritional Value and Oxidative Stability of Vegetable Oils

Oil oxidation is the main factor limiting vegetable oils' quality during storage, as it leads to the deterioration of oil's nutritional quality and gives rise to disagreeable flavors. These changes make fat-containing foods less acceptable to consumers. To deal with this problem and to meet consumer demand for natural foods, vegetable oil fabricators and the food industry are looking for alternatives to synthetic antioxidants to protect oils from oxidation. In this context, natural antioxidant compounds extracted from different parts (leaves, roots, flowers, and seeds) of medicinal and aromatic plants (MAPs) could be used as a promising and sustainable solution to protect consumers' health. The objective of this review was to compile published literature regarding the extraction of bioactive compounds from MAPs as well as different methods of vegetable oils enrichment. In fact, this review uses a multidisciplinary approach and offers an updated overview of the technological, sustainability, chemical and safety aspects related to the protection of oils.

Antioxidant potential and molecular docking of bioactive compound of Camellia sinensis and Camellia assamica with cytochrome P450

Camellia sinensis and Camellia assamica are well known for their medicinal and therapeutic potential. The purpose of this work is to assess the flavonoid content and antioxidant potential of methanol extracts of C. sinensis (MES) and acetone extract of C. assamica (AEA) experimentally and computationally. Qualitative analysis was done to assess the presence of flavonoids. Further, the antioxidant potential of MES and AEA was done by ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)) and superoxide free radical-scavenging activity. The profiling of functional groups was analyzed by FT-IR analysis. The bioactive compounds n-heptadecanol-1 of MES and 2',6'-dihydroxyacetophenone, bis(trimethylsilyl) ether of AEA were procured from our previous study to analyze their antioxidant potential computationally (Auto-dock Vina). Both the extracts showed their potential to neutralize free radicals with variable potency. The study of the molecular interactions revealed that both the extracts MES and AEA interacted to the active site with higher binding energy. This work deduced that n-heptadecanol-1 and 2',6'-dihydroxyacetophenone, bis(trimethylsilyl) ether have good potential to inhibit and scavenge the free radicals.

The effect of in vitro gastrointestinal digestion on the phenolic profiles, bioactivities and bioaccessibility of Rhodiola

Changes in the phenolic profiles and antioxidant and antiproliferative activities of Rhodiola after simulated in vitro digestion were first assessed in this study. Furthermore, permeability and uptake assays as well as RT-qPCR and western blot analyses were performed in order to explore the bioaccessibility of the digesta and its underlying mechanism. The results reveal that in vitro gastrointestinal digestion significantly reduced the total phenolics and total flavonoids as well as the extracellular, cellular antioxidant and antiproliferative activities of Rhodiola, in which the colon digesta had the largest reduction. However, in vitro digestion augmented the cellular uptake rates of Rhodiola phenolics with higher permeability coefficients. The colon digesta (GA-Dig) exhibited the highest uptake of gallic acid (GA, the main compound) instead of GA in its pure form, indicating the synergistic effects of GA and other phenolics in Rhodiola. In-depth mechanistic studies suggest that the fabulous uptake rates and permeability coefficients of the colon digesta were triggered by the down-regulation of the expression levels of ABCF2 mRNA and protein. These findings indicate that simulated gastrointestinal digestion could promote the bioaccessibility and bioactivities of phenolics in Rhodiola.

Insights into the release mechanisms of antioxidants from nanoemulsion droplets

The therapeutic effects of antioxidant-loaded nanoemulsion can be often optimized by controlling the release rate in human body. Release kinetic models can be used to predict the release profile of antioxidant compounds and allow identification of key parameters that affect the release rate. It is known that one of the critical aspects in establishing a reliable release kinetic model is to understand the underlying release mechanisms. Presently, the underlying release mechanisms of antioxidants from nanoemulsion droplets are not yet fully understood. In this context, this review scrutinized the current formulation strategies to encapsulate antioxidant compounds and provide an outlook into the future of this research area by elucidating possible release mechanisms of antioxidant compounds from nanoemulsion system.

Sustainable Green Processing of Grape Pomace Using Micellar Extraction for the Production of Value-Added Hygiene Cosmetics

This study sought to evaluate the possibility of using grape pomace, a waste material from wine production, for the preparation of cosmetic components. Following the existing clear research trend related to improving the safety of cleansing cosmetics, an attempt was made to determine the possibility of preparing model shower gels based on grape pomace extract. A new method for producing cosmetic components named loan chemical extraction (LCE) was developed and is described for the first time in this paper. In the LCE method, an extraction medium consisting only of the components from the final product was used. Thus, there were no additional substances in the cosmetics developed, and the formulation was significantly enriched with compounds isolated from grape pomace. Samples of the model shower gels produced were evaluated in terms of their basic parameters related to functionality (e.g., foaming properties, rheological characteristics, color) and their effect on the skin. The results obtained showed that the extracts based on waste grape pomace contained a number of valuable cosmetic compounds (e.g., organic acids, phenolic compounds, amino acids and sugars), and the model products basis on them provided colorful and safe natural cosmetics.

Integrated strategies for enzyme assisted extraction of bioactive molecules: A review

Conventional methods of extracting bioactive molecules are gradually losing pace due to their numerous disadvantages, such as product degradation, lower efficiency, and toxicity. Thus, in light of the rising demand for these bioactive, enzymes have garnered much attention for their efficiency in extraction. However, enzyme-assisted extraction is also plagued with a high capital cost that cannot justify the extraction yields obtained. In order to mitigate these problems, enzyme-assisted extraction can be consorted with non-conventional methods. This review includes current progress concerning the combined approaches while converging the recent advancements in the field that outperformed conventional extraction processes. It also highlights the design of biocatalyst and key parameters involved in the effective extraction of bioactive molecules. An integrated approach for efficiently extracting polyphenols, essential oils, pigments, and vitamins has been comprehensively reviewed. Furthermore, the different immobilization strategies have been discussed for large-scale implementation of enzymes for extraction. The integration of advanced non-conventional methods with enzyme-assisted extraction will open new avenues to enhance the overall extraction efficiency.

Therapeutic Targets for Phenolic Compounds from Agro-industrial Byproducts against Obesity

BACKGROUND

Obesity is considered as a global epidemic worldwide. This disorder is associated to several health effects such as metabolic disturbances that need both prevention and treatment actions. In this sense, bioactive secondary metabolites can be obtained from cheap sources such as agro-industrial waste providing a sustainable alternative against obesity. Among these secondary metabolites, phenolic compounds present a common chemical structure core with different substitutions that provides them biological properties such as antioxidant, inflammatory, anti-aging capacities.

OBJECTIVE

The aim of this review is to compile anti-obesity therapeutic targets for phenolic compounds from agro-industrial byproducts.

METHOD

Scientific information has been obtained from different databases such as Scopus, PubMed and Google Scholar in order to select the available full text studies in last years.

RESULTS

This review shows that peel, seed, pomace and other byproducts from agro-industry have different effects inhibiting enzymes related to lipid or glucose metabolism and modulating biomarkers, genes and gut microbiota in animal models.

CONCLUSION

Revalorizing actions of agro-industrial byproducts in the prevention or treatment of obesity or associated disorders can be considered to develop new high value products that act on lipid, glucose and energy metabolisms, oxidative stress, inflammation, adipose tissue or gut microbiota. However, further human studies are need in order to stablish the optimal administration parameters.

Phytochemical profiling of Blumea laciniata (Roxb.) DC. and its phytopharmaceutical potential against diabetic, obesity, and Alzheimer's

Blumea laciniata (Roxb.) DC. is a folk medicinal annual herb of the Asteraceae family that grows in South and Southeast Asia. In order to evaluate its phytopharmaceutical potential against diabetic, obesity, and Alzheimer's, a comprehensive phytochemical profile, in vitro and in silico enzyme inhibitory activity against α-amylase, α-glucosidase, lipase, cholinesterases, and tyrosinase along with in vitro antioxidant activity were performed. Additionally, in vivo antidiabetic activity and acute toxicity were also evaluated. The total phenolic content in various organs follows the following order: old leaf > flower bud > young leaf > flower > young stem > old stem > root, while total flavonoids followed the order: flower bud > old leaf > young leaf > flower > young stem > old stem > root. The identified phenolic compounds are 3,4-dihydroxybenzoic acid, caffeic acid, vanillic acid, p-coumaric acid, syringic acid, rosmarinic acid, trans-cinnamic acid, catechin, catechol, (-) epicatechin, rutin, quercetin, myricetin, and kaempferol, which are also expressed differently in various organs. Solvent extracts demonstrated strong antioxidant activity as well as varying levels of inhibition against the enzymes tested, with strong inhibitory activity against α-amylase, α-glucosidase, and lipase. Thirteen phenolic compounds displayed strong binding affinity in silico against studied enzymes, thus documented as bioactive. Furthermore, solvent extracts significantly suppressed blood glucose levels in mice with induced diabetes and extracts were not acutely toxic. The results suggest that Blumea laciniata (Roxb.) DC. could be a potential candidate for developing new phytopharmaceuticals and bioactive ingredients.

Neuroprotective Potency of Tofu Bio-Processed Using Actinomucor elegans against Hypoxic Injury Induced by Cobalt Chloride in PC12 Cells

Fermented soybean products have attracted great attention due to their health benefits. In the present study, the hypoxia-injured PC12 cells induced by cobalt chloride (CoCl₂) were used to evaluate the neuroprotective potency of tofu fermented by Actinomucor elegans (FT). Results indicated that FT exhibited higher phenolic content and antioxidant activity than tofu. Moreover, most soybean isoflavone glycosides were hydrolyzed into their corresponding aglycones during fermentation. FT demonstrated a significant protective effect on PC12 cells against hypoxic injury by maintaining cell viability, reducing lactic dehydrogenase leakage, and inhibiting oxidative stress. The cell apoptosis was significantly attenuated by the FT through down-regulation of caspase-3, caspases-8, caspase-9, and Bax, and up-regulation of Bcl-2 and Bcl-xL. S-phase cell arrest was significantly inhibited by the FT through increasing cyclin A and decreasing the p21 protein level. Furthermore, treatment with the FT activated autophagy, indicating that autophagy possibly acted as a survival mechanism against CoCl₂-induced injury. Overall, FT offered a potential protective effect on nerve cells in vitro against hypoxic damage.

Extraction of phenolic compounds: A review

Phenolic compounds are parts of secondary metabolites mostly found in plant species with enormous structural diversities. They can exist as glycosides or aglycones; matrix or free-bound compounds; and comprising mostly polymerized or monomer structures. Additionally, these compounds are not universally dispensed within plants with varied stability. This has contributed to challenging extraction processes; implying that employing a single step or inappropriate extraction technique might change the recovery of phenolic components from the plant samples. Hence, it is important to select an appropriate extraction method so as to recover the targeted phenolic compounds. This is will helps to recover substantial yields from the sample matrix. Therefore, this review mainly focuses on the phenolic compounds and several methods of extraction that are used to obtaining them from plant materials. These extraction methods includes both conventional and unconventional techniques.

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Phenolic compounds from natural sources.

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Methods of extracting phenolic compounds.

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Selection of an appropriate extraction method to recover the targeted phenolic compounds from plant materials.

Techniques and modeling of polyphenol extraction from food: a review

There is a growing demand for vegetal food having health benefits such as improving the immune system. This is due in particular to the presence of polyphenols present in small amounts in many fruits, vegetables and functional foods. Extracting polyphenols is challenging because extraction techniques should not alter food quality. Here, we review technologies for extracting polyphenolic compounds from foods. Conventional techniques include percolation, decoction, heat reflux extraction, Soxhlet extraction and maceration, whereas advanced techniques are ultrasound-assisted extraction, microwave-assisted extraction, supercritical fluid extraction, high-voltage electric discharge, pulse electric field extraction and enzyme-assisted extraction. Advanced techniques are 32-36% more efficient with approximately 15 times less energy consumption and producing higher-quality extracts. Membrane separation and encapsulation appear promising to improve the sustainability of separating polyphenolic compounds. We present kinetic models and their influence on process parameters such as solvent type, solid and solvent ratio, temperature and particle size.

In silico study of garlic (Allium sativum L.)-derived compounds molecular interactions with α-glucosidase

Diabetes mellitus is a metabolic syndrome characterized by elevated blood glucose. The α-glucosidase enzyme is responsible for the hydrolysis of carbohydrates. This in silico study aimed to evaluate the inhibitory effects of the isolated compounds from Allium sativum L. on α-glucosidase. At first, sulfur and phenolic compounds of A. sativum L. were obtained from PubChem database, and α-glucosidase enzyme structure was obtained from Protein Data Bank. Toxicity class of compounds and the Lipinski parameter were predicted by Toxtree and Protox II and the Swiss ADME tools, respectively. Finally, the molecular interaction analysis between α-glucosidase and compounds from A. sativum L. was performed by AutoDock 4.2.6. Molecular interactions were investigated using Discovery Studio Visulizer and Ligplot 2.1 program. All of the selected sulfur and phenolic compounds from A. sativum L. followed the Lipinski's rules, had an acceptable binding energy, and lacked toxicity; therefore, they were appropriate candidates for α-glucosidase inhibition. Among these compounds, methionol and caffeic acid showed the lowest binding energy, and the highest inhibitory effect on α-glucosidase enzyme with - 3.9 and - 4.8 kcal/mol, respectively. These compounds also indicated the lower binding energy than the standard inhibitor (miglitol). Among the sulfur and phenolic compounds in A. sativum L., methionol and caffeic acid were predicted to be the powerful inhibitors, due to having more hydrogen binds and hydrophobic interactions with the active site of α-glucosidase.

Do Flavonoids from Durum Wheat Contribute to Its Bioactive Properties? A Prospective Study

A clear gap with respect to the potential biological properties of wheat flavonoids exists in the available literature. This information is crucial for breeding programs aiming to produce new varieties presenting improved health benefits. Accordingly, advanced breeding lines of whole durum wheat were evaluated in this contribution. The highest recovery of phenolics was achieved using aqueous acetone (50:50, v/v), as verified by multi-response optimization, thus showing that phenolics could be largely underestimated by employing an inappropriate extraction. The concentration of derivatives of apigenin, the main phenolics present, ranged from 63.5 to 80.7%, as evaluated by LC-ESI-QTOF-MS. Phenolics from the breeding line 98 exhibited the highest ability in scavenging peroxyl radicals, reducing power as well as in terms of inhibition of pancreatic lipase activity, a key enzyme regulating the absorption of triacylglycerols. In contrast, none of the samples exhibited a significant anti-diabetic potential. Despite their high concentration compared to that of phenolic acids, results of this work do not support a significant antioxidant and pancreatic lipase inhibitory effect of durum wheat flavonoids. Therefore, breeding programs and animal and/or human trials related to the effect of durum wheat flavonoids on oxidative stress and absorption of triacylglycerols are discouraged at this point.

Fungal pretreatment to enhance the yield of phytochemicals and evaluation of α-amylase and α-glucosidase inhibition using Cinnamomum zeylanicum (L.) quills pressurized water extracts

Bioactive compounds entrapped in plant materials can be effectively recovered using fungal enzymes. Cinnamomum zeylanicum Sri Wijaya (SW) and Sri Gemunu (SG) accessions and commercially available C. zeylanicum (CC) were subjected to fungal pretreatment and extracted with pressured water (PWE, 0·098 MPa). Thirteen fungal species were isolated and the substrate utilization ability of the species was tested using cellulose, pectin and lignin (indirectly). Total phenolic content (TPC, Folin-Ciocalteu method), proanthocyanidin content (PC, vanillin method) and α-amylase and α-glucosidase inhibitory potential of the extracts were evaluated. The anti-diabetic drug, Acarbose was used as the positive control. Trichoderma harzianum (MH298760) showed the highest cell lysis ability and hence was used for the microbial pretreatment process. Extracts of SW treated with T. harzianum species (Pre-SW) gave the highest percentage yield (4·08% ± 0·15%), significantly potent inhibition (P < 0·05) of α-amylase and α-glucosidase activities (IC₅₀ 57 ± 8 and 36 ± 8 μg ml^-1 respectively), TPC (2·24 ± 0·02 mg gallic acid equivalent g^-1 ), and PC (48·2 ± 0·4 mg of catechin equivalent g^-1 ) compared to Pre-SG, Pre-CC and nontreated samples. Trichoderma harzianum treatment can enhance the hypoglycaemic properties, PC and TPC of Cinnamon extracts and provide new insights into the recovery of phytochemicals.

One Pot Use of Combilipases for Full Modification of Oils and Fats: Multifunctional and Heterogeneous Substrates

Lipases are among the most utilized enzymes in biocatalysis. In many instances, the main reason for their use is their high specificity or selectivity. However, when full modification of a multifunctional and heterogeneous substrate is pursued, enzyme selectivity and specificity become a problem. This is the case of hydrolysis of oils and fats to produce free fatty acids or their alcoholysis to produce biodiesel, which can be considered cascade reactions. In these cases, to the original heterogeneity of the substrate, the presence of intermediate products, such as diglycerides or monoglycerides, can be an additional drawback. Using these heterogeneous substrates, enzyme specificity can promote that some substrates (initial substrates or intermediate products) may not be recognized as such (in the worst case scenario they may be acting as inhibitors) by the enzyme, causing yields and reaction rates to drop. To solve this situation, a mixture of lipases with different specificity, selectivity and differently affected by the reaction conditions can offer much better results than the use of a single lipase exhibiting a very high initial activity or even the best global reaction course. This mixture of lipases from different sources has been called “combilipases” and is becoming increasingly popular. They include the use of liquid lipase formulations or immobilized lipases. In some instances, the lipases have been coimmobilized. Some discussion is offered regarding the problems that this coimmobilization may give rise to, and some strategies to solve some of these problems are proposed. The use of combilipases in the future may be extended to other processes and enzymes.

Characterization, bioavailability and protective effects of phenolic-rich extracts from almond hulls against pro-oxidant induced toxicity in Caco-2 cells

Almond hulls, the main by-product of almond production, are considered a valuable source of bioactive phenolic compounds. This study aimed to characterize the phenolic composition, bioavailability of the phenolic-rich extracts from almond hulls (PEAH), and their protective effect on oxidative stressed Caco-2 cells induced by tert-butylhydroperoxide (t-BOOH). The ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS) analysis detected 11 phenolic compounds in the PEAH with high total phenolic content and antioxidant activity. Oxidative Caco-2 cell damage was reduced by PEAH, especially at 5 μg/mL, through scavenging reactive oxygen species (ROS), modulating the cellular endogenous antioxidant system and cell redox at a predictable status. Also, in vitro digestion influenced the phenolic compounds' composition and antioxidant power of PEAH. These results suggested that almond hulls, rich in phenolic compounds, can meliorate the oxidative stressed Caco-2 cells and restore its impaired redox balance, and ultimately improve health benefits.

Review of Distribution, Extraction Methods, and Health Benefits of Bound Phenolics in Food Plants

Phenolic compounds are important functional bioactive substances distributed in various food plants. They have gained wide interest from researchers due to their multiple health benefits. There are two forms of phenolic compounds: free form and bound form. The latter is also called bound phenolics (BPs), which are found mainly in the cell wall and distributed in various tissues/organs of the plant body. They can either chemically bind to macromolecules and food matrixes or be physically entrapped in food matrixes and intact cells. Various isolation methods, including chemical, biological, and physical methods, have been employed to extract BPs from plants. BPs have been shown to have strong biological activities, including antioxidant, probiotic, anticancer, anti-inflammation, antiobesity, and antidiabetic effects as well as beneficial effects on central nervous system diseases. This review summarizes research findings on these topics to help in better understanding of BPs and provide comprehensive information on their health effects.