Polyphenols of peanut (Arachis hypogaea L.) skin as bioprotectors of normal cells. Studies of cytotoxicity, cytoprotection and interaction with ROS

Biotechnological trends and optimization of Arachis hypogaea residues valorization: A bibliometric analysis and comprehensive review

This review thoroughly explores the valorization of Arachis hypogaea (groundnut) residues for producing high-value bioproducts such as biofuels, biocatalysts, biochar, and nanomaterials through processes like pyrolysis, gasification, and enzymatic conversion. Optimization techniques, including Response Surface Methodology (RSM), Artificial Neural Networks (ANNs), and Adaptive Neuro-Fuzzy Inference Systems (ANFIS), have led to significant enhancements in bioproduct yields. A detailed bibliometric analysis spanning from 2000 to the present highlights key research trends and influential contributors, reflecting the increasing global focus on groundnut residue valorization. The study emphasizes the environmental and economic benefits, such as improved waste management, reduced greenhouse gas emissions, and contributions to a circular bioeconomy. It advocates for policy frameworks that support these biotechnological advancements and recommends further research on process scalability, long-term stability, and life cycle assessments to ensure the environmental and economic viability of groundnut residue utilization in sustainable development.

Anticancer Potential of Valencia Peanut (Arachis hypogaea L.) Skin Extract against Cervical Cancer Cells In Vitro and in Nude Mouse Xenograft Models

This study investigated the impact of Valencia KK4-type peanut skin ethanolic extract (KK4-PSE) combined with cisplatin or 5-fluorouracil (5-FU) on HeLa cells in vitro and in xenograft models. At exposure times of 24, 48 and 72 h, KK4-PSE inhibited the growth of HeLa cells with a half maximal inhibitory concentration (IC50) of 79.43 ± 0.54, 55.55 ± 1.57 and 41.32 ± 0.74 µg/mL, respectively. Drug interactions evaluated by the Chou-Talalay method demonstrated that KK4-PSE enhanced antiproliferative activity of 5-FU against HeLa cells with combination index (CI) values of 0.49 (48 h) and 0.60 (72 h), indicating a synergistic effect, while KK4-PSE combined with cisplatin exhibited an additive effect (CI = 1.02) at 72 h, and an antagonistic effect at 24 and 48 h exposures (CI = 1.12 and 1.18, respectively). In nude mouse xenograft models, the combination of 5-FU and KK4-PSE markedly reduced HeLa tumor weights compared with the control and single agent treatments groups. The combination of KK4-PSE and 5-FU achieved greater tumor growth inhibition than that of the KK4-PSE-cisplatin combination. KK4-PSE mitigated hepatotoxicity induced by both cisplatin and 5-FU in nude mice. The spleen hyaloserositis was significantly reduced in the combination treatment of 5-FU and KK4-PSE. These results suggest that KK4-PSE has the potential to limit cervical cancer cell proliferation while reducing the toxicity of cisplatin and 5-FU.

Groundnut and tree nuts: a comprehensive review on their lipid components, phytochemicals, and nutraceutical properties

The health benefits of nut consumption have been extensively demonstrated in observational studies and intervention trials. Besides the high nutritional value, countless evidences show that incorporating nuts into the diet may contribute to health promotion and prevention of certain diseases. Such benefits have been mostly and certainly attributed not only to their richness in healthy lipids (plentiful in unsaturated fatty acids), but also to the presence of a vast array of phytochemicals, such as polar lipids, squalene, phytosterols, tocochromanols, and polyphenolic compounds. Thus, many nut chemical compounds apply well to the designation "nutraceuticals," a broad umbrella term used to describe any food component that, in addition to the basic nutritional value, can contribute extra health benefits. This contribution analyses the general chemical profile of groundnut and common tree nuts (almond, walnut, cashew, hazelnut, pistachio, macadamia, pecan), focusing on lipid components and phytochemicals, with a view on their bioactive properties. Relevant scientific literature linking consumption of nuts, and/or some of their components, with ameliorative and/or preventive effects on selected diseases - such as cancer, cardiovascular, metabolic, and neurodegenerative pathologies - was also reviewed. In addition, the bioactive properties were analyzed in the light of known mechanistic frameworks.

Bioactive compounds of peanut skin in prevention and adjunctive treatment of chronic non-communicable diseases

The global prevalence of cancer continues to increase, so does its mortality. Strategies that can prevent/treat this condition are therefore required, especially low-cost and low-toxicity strategies. Bioactive compounds of plant origin have been presented as a good alternative. In this scenario, due to its abundant polyphenolic content (around 60 to 120 times greater than that of the grain), peanut skin by-products stand out as a sustainable source of food bioactives beneficial to human health. Investigated studies highlighted the importance of peanut skin for human health, its phytochemical composition, bioactivity and the potential for prevention and/or adjuvant therapy in cancer, through the advanced search for articles in the Virtual Health Library (VHL), Science direct and the Mourisco platform of the FioCruz Institute, from 2012 to 2022. Using the keywords, "peanut skin" AND "cancer" AND NOT "allergy", the words "peanut testa" and "peanut peel" were included replacing "peanut skin". 18 articles were selected from Plataforma Mourisco, 26 from Science Direct and 26 from VHL. Of these, 7 articles evaluated aspects of cancer prevention and/or treatment. Promising benefits were found in the prevention/treatment of chronic non-communicable diseases in the use of peanut and peanut skin extracts, such as cholesterolemia and glucose control, attenuation of oxidative stress and suppressive action on the proliferation and metabolism of cancer cells.

Peanut (Arachis hypogaea L.) seeds and by-products in metabolic syndrome and cardiovascular disorders: A systematic review of clinical studies

BACKGROUND

Cardiovascular disease (CVDs) is the leading cause of death worldwide. The main risk factors are hypertension, diabetes, obesity, and increased serum lipids. The peanut (Arachis hypogaea L.), also known as the groundnut, goober, pindar, or monkey nut, belongs to the Fabaceae family and is the fourth most cultivated oilseed in the world. The seeds and skin of peanuts possess a rich phytochemical profile composed of antioxidants, such as phenolic acids, stilbenes, flavonoids, and phytosterols. Peanut consumption can provide numerous health benefits, such as anti-obesity, antidiabetic, antihypertensive, and hypolipidemic effects. Accordingly, peanuts have the potential to treat CVD and counteract its risk factors.

PURPOSE

This study aims to critically evaluate the effects of peanuts on metabolic syndrome (MetS) and CVD risk factors based on clinical studies.

METHOD

This review includes studies indexed in MEDLINE-PubMed, COCHRANE, and EMBASE, and the Preferred Reporting Items for a Systematic Review and Meta-Analysis guidelines were adhered to.

RESULTS

Nineteen studies were included and indicated that the consumption of raw peanuts or differing forms of processed foods containing peanut products and phytochemicals could improve metabolic parameters, such as glycemia, insulinemia, glycated hemoglobin, lipids, body mass index, waist circumference, atherogenic indices, and endothelial function.

CONCLUSION

We propose that this legume and its products be used as a sustainable and low-cost alternative for the prevention and treatment of MetS and CVD. However, further research with larger sample sizes, longer intervention durations, and more diverse populations is needed to understand the full benefit of peanut consumption in MetS and CVD.

Chitosan-glucose derivative as effective wall material for probiotic yeasts microencapsulation

A chitosan-glucose derivative (ChG) with lower antimicrobial activity against whey native probiotic yeast K. marxianus VM004 was synthesized by the Maillard reaction. The ChG derivative was characterized by FT-IR, 1H NMR, and SLS to determine the structure, deacetylation degree (DD), and molecular weight (Mw). In addition, we evaluated the antioxidant, cytotoxic, and antimicrobial activities of ChG. ChG was then used for microencapsulation of K. marxianus VM004 by spray drying. The microcapsules were characterized by evaluating their encapsulation yield, encapsulation efficiency, morphology, tolerance to the gastrointestinal tract, and viability during storage. The results indicated that a non-cytotoxic product with lower MW and DD and higher antioxidant activity than native chitosan was obtained by the Maillard reaction. The yeast ChG microcapsules exhibited an encapsulation efficiency >57 %, improved resistance to gastrointestinal conditions, and enhanced stability during storage. These results demonstrate that ChG may be a promising wall material for the microencapsulation of probiotic yeasts.

In Vitro Digestion of Peanut Skin Releases Bioactive Compounds and Increases Cancer Cell Toxicity

Peanut skin is a rich source of bioactive compounds which may be able to reduce the risk factors associated with metabolic syndromes. This study aimed to characterize bio-compounds from peanut skin (Arachis hypogaea) and their bioactivity (antioxidant activity, inhibition of lipase, and carbohydrase enzymes) and to evaluate their anti-proliferative properties in colorectal cancer cells (HCT116) upon in vitro digestion. Peanut skin was digested in two sequential phases, and the final content, named phase-1 (P1) and phase-2 (P2) extracts, was evaluated. Several bioactive compounds were positively identified and quantified by liquid chromatography, including quinic acid, released especially after in vitro digestion. The total phenolic content and, regardless of the method, the antioxidant activity of P1 was higher than P2. P1 also showed a lower enzyme inhibitory concentration IC₅₀ than P2, lipase, and α-glucosidase. For cell viability in HCT116 cells, lower concentrations of P1 were found for IC₅₀ compared to P2. In conclusion, bioactive compounds were released mainly during the first phase of the in vitro digestion. The digested samples presented antioxidant activity, enzyme inhibitory activity, and cancer cell cytotoxicity, especially those from the P1 extract. The potential applications of such a by-product in human health are reported.

Preparation and characterization of antibacterial, antioxidant, and biocompatible p-coumaric acid modified quaternized chitosan nanoparticles

To fabricate multifunctional nanoparticles (NPs) based on chitosan (CS) derivative, we first prepared quaternized CS (2-hydroxypropyltrimethyl ammonium chloride CS, HTCC) via a one-step approach, then synthesized p-coumaric acid (p-CA) modified HTCC (HTCC-CA) for the first time through amide reaction, and finally fabricated a series of NPs (HTCC-CA NPs) using HTCC-CAs with different substitution degrees and sodium tripolyphosphate (TPP) by ionic gelation. Newly-prepared HTCC and HTCC-CAs were characterized by FT-IR, ¹H NMR, elemental analysis (EA), full-wavelength UV scanning, silver nitrate titration, and Folin-Ciocalteu methods. DLS and TEM results demonstrated that three selected HTCC-CA NPs had moderate size (< 350 nm), good dispersion (PDI < 0.4), and positive zeta potential (11-20 mV). The HTCC-CA NPs had high antibacterial activity against six bacterial strains, and the minimum inhibitory concentration (MIC) values were almost the same as the minimum bactericidal concentration (MBC) values (250-1000 μg/mL). Also, the HTCC-CA NPs had good antioxidation (radical scavenging ratio > 65 %) and low cytotoxicity (relative cell viability >80 %) to the tested cells. Totally, HTCC-CA NPs with high antibacterial activity, great antioxidation, and low cytotoxicity might serve as new biomedical materials for promoting skin wound healing.

Holistic Photoprotection, Broad Spectrum (UVA-UVB), and Biological Effective Protection Factors (BEPFs) from Baccharis antioquensis Hydrolysates Polyphenols

Overexposure to solar radiation has become an increasingly worrying problem due to the damage to the skin caused by ultraviolet radiation (UVR). In previous studies, the potential of an extract enriched with glycosylated flavonoids from the endemic Colombian high-mountain plant Baccharis antioquensis as a photoprotector and antioxidant was demonstrated. Therefore, in this work we sought to develop a dermocosmetic formulation with broad-spectrum photoprotection from the hydrolysates and purified polyphenols obtained from this species. Hence, the extraction of its polyphenols with different solvents was evaluated, followed by hydrolysis and purification, in addition to the characterization of its main compounds by HPLC-DAD and HPLC-MS, and evaluation of its photoprotective capacity through the measurement of the Sun Protection Factor (SPF), UVA Protection Factor (UVAPF), other Biological Effective Protection Factors (BEPFs), and its safety through the cytotoxicity. In the dry methanolic extract (DME) and purified methanolic extract (PME), flavonoids such as quercetin and kaempferol were found, which demonstrated antiradical capacity, as well as UVA-UVB photoprotection and prevention of harmful biological effects, such as elastosis, photoaging, immunosuppression, DNA damage, among others, which demonstrates the potential of the ingredients in this type of extract to be applied in photoprotection dermocosmetics.

Phenolic Fraction from Peanut (Arachis hypogaea L.) By-product: Innovative Extraction Techniques and New Encapsulation Trends for Its Valorization

Peanut skin is a by-product rich in bioactive compounds with high nutritional and pharmaceutical values. The phenolic fraction, rich in proanthocyanidins/procyanidins, is a relevant class of bioactive compounds, which has been increasingly applied as functional ingredients for food and pharmaceutical applications and is mostly recovered from peanut skins through low-pressure extraction methods. Therefore, the use of green high-pressure extractions is an interesting alternative to value this peanut by-product. This review addresses the benefits of the phenolic fraction recovered from peanut skin, with a focus on proanthocyanin/procyanidin compounds, and discusses the improvement of their activity, bioavailability, and protection, by methods such as encapsulation. Different applications for the proanthocyanidins, in the food and pharmaceutical industries, are also explored. Additionally, high-pressure green extraction methods, combined with micro/nanoencapsulation, using wall material derived from peanut industrial processing, may represent a promising biorefinery strategy to improve the bioavailability of proanthocyanidins recovered from underutilized peanut skins.

Nutraceutical and Pharmaceutical Behavior of Bioactive Compounds of Miracle Oilseeds: An Overview

India plays an important role in the production of oilseeds, which are mainly cultivated for future extraction of their oil. In addition to the energic and nutritional contribution of these seeds, oilseeds are rich sources of bioactive compounds (e.g., phenolic compounds, proteins, minerals). A regular and moderate dietary supplementation of oilseeds promotes health, prevents the appearance of certain diseases (e.g., cardiovascular diseases (CVDs), cancers) and delays the aging process. Due to their relevant content in nutraceutical molecules, oilseeds and some of their associated processing wastes have raised interest in food and pharmaceutical industries searching for innovative products whose application provides health benefits to consumers. Furthermore, a circular economy approach could be considered regarding the re-use of oilseeds’ processing waste. The present article highlights the different oilseed types, the oilseeds-derived bioactive compounds as well as the health benefits associated with their consumption. In addition, the different types of extractive techniques that can be used to obtain vegetable oils rich from oilseeds, such as microwave-assisted extraction (MAE), ultrasonic-assisted extraction (UAE) and supercritical fluid extraction (SFE), are reported. We conclude that the development and improvement of oilseed markets and their byproducts could offer even more health benefits in the future, when added to other foods.

An overview on extraction, composition, bioactivity and food applications of peanut phenolics

Peanuts contain a diverse and vast array of phenolic compounds having important biological properties. They are allocated mostly in the seed coat (skin), an industrial waste with minor and undervalued applications. In the last few years, a considerable amount of scientific knowledge about extraction, composition, bioactivities and health benefits of peanut skin phenolics has been generated. The present review was focused on four main aspects: a) extraction methods and technologies for obtaining peanut skin phenolics with an emphasis on green-solvent extraction processes; b) variations in chemical profiles including those due to genetic variability, extraction methodologies and process-related issues; c) bioactive properties, especially antioxidant activities in food and biological systems; d) update of promising food applications. The revision was also aimed at identifying areas where knowledge is insufficient and to set priorities for further research.

Bioactive Ingredients Obtained from Agro-industrial Byproducts: Recent Advances and Innovation in Micro- and Nanoencapsulation

The agro-industry produces numerous byproducts that are currently underused, and its waste contributes to environmental pollution. These byproducts represent an important and economical source of bioactive ingredients, which can promote the sustainable development of high-value-added functional foods. In this context, micro- and nanoencapsulation systems allow for the incorporation and stabilization of the bioactive agents in foods. This perspective will review recent advances in the use of agro-industrial byproducts as a source of bioactive agents. In addition, the latest advances in micro- and nanoencapsulation to improve the stability, solubility, and bioaccessibility of bioactive agents as functional food ingredients are exposed.

Characterization, Antioxidant and Anti-Inflammation Capacities of Fermented Flammulina velutipes Polyphenols

This work investigated the preparation, characterization, antioxidant, and anti-inflammation capacities of Flammulina velutipes polyphenols (FVP) and fermented FVP (FFVP). The results revealed that the new syringic acid, accounting for 22.22%, was obtained after fermentation (FFVP). FFVP exhibits higher antioxidant and anti-inflammation activities than FVP, enhancing cell viability and phagocytosis, inhibiting the secretion of NO and ROS, and reducing the inflammatory response of RAW264.7 cells. This study revealed that FFVP provides a theoretical reference for in-depth study of its regulatory mechanisms and further development of functional antioxidants that are applicable in the food and health industry.

Extracts of Peanut Skins as a Source of Bioactive Compounds: Methodology and Applications

Peanut skins are a waste product of the peanut processing industry with little commercial value. They are also significant sources of the polyphenolic compounds that are noted for their bioactivity. The extraction procedures for these compounds range from simple single solvent extracts to sophisticated separation schemes to isolate and identify the large range of compounds present. To take advantage of the bioactivities attributed to the polyphenols present, a range of products both edible and nonedible containing peanut skin extracts have been developed. This review presents the range of studies to date that are dedicated to extracting these compounds from peanut skins and their various applications.