Antimicrobial activity and composition profile of grape (Vitis vinifera) pomace extracts obtained by supercritical fluids

Unleashing the potential of vanillic acid: A new twist on nature's recipe to fight inflammation and circumvent azole-resistant fungal infections

Vanillic acid (VA) - a naturally occurring phenolic compound in plants - is not only used as a flavoring agent but also a prominent metabolite post tea consumption. VA and its associated compounds are believed to play a significant role in preventing diseases, underscoring the need for a systematic investigation. Herein, we report a 4-step synthesis employing the classical organic reactions, such as Willamson's alkylation, Fischer-Spier reaction, and Steglich esterification, complemented with a protection-deprotection strategy to prepare 46 VA derivatives across the five series (1a-1i, 2a-2i, 3, 3a-3i, 4a-4i, 5a-5i) in high yields. The synthesized compounds were investigated for their antifungal, anti-inflammatory, and toxic effects. Notably, compound 1a demonstrated remarkable ROS inhibition with an IC50 value of 5.1 ± 0.7 µg/mL, which is more than twice as effective as the standard ibuprofen drug. A subset of the synthesized derivatives (2b, 2c, 2e, 3b-3d, 4a-4c, 5a, and 5e) manifested their antifungal effect against drug-resistant Candida strains. Compound 5g, in particular, revealed synergism with the established antifungal drugs amphotericin B (AMB) and fluconazole (FLZ), doubling FLZ's potency against azole resistant Candida albican ATCC 36082. Furthermore, 5g improved the potency of these antifungals against FLZ-sensitive strains, including C. glabrata ATCC 2001 and C. parapsilosis ATCC 22019, as well as various multidrug-resistant (MDR) Candida strains, namely C. albicans ATCC 14053, C. albicans CL1, and C. krusei SH2L OM341600. Additionally, pharmacodynamics of compound 5g was examined using time-kill assay, and a benign safety profile was observed with no hemolytic activity in whole blood, and no cytotoxicity towards the normal BJ human cell line. The synergistic potential of 5g was further investigated through both experimental methods and docking simulations.These findings highlight the therapeutic potential of VA derivatives, particularly in addressing inflammation and circumventing FLZ resistance in Candida albicans.

Use of red grape pomace and Aloe vera gel as nutraceuticals to ameliorate stocking density-induced stress in commercial male broilers

The combined effect of Aloe vera gel (AVG) administered through drinking water and dietary red grape pomace powder (RGP) on growth performance, physiological traits, welfare indicators, and meat quality in densely stocked broilers was evaluated. A total of 750, two-week-old male Ross 308 broilers (317.7 ± 10.12 g live weight) were randomly assigned to 25 cages, with each cage as an experimental unit. The broilers were stocked at a density of 30 birds per cage with a floor space of 1.32 m2. Dietary treatments were a standard grower or finisher diet (CON); CON containing 30 g RGP /kg diet plus either 1 (GPA1), 2 (GPA2), 3 (GPA3), or 4% (GPA4) AVG in drinking water. Treatment GPA1 promoted higher (P < 0.05) overall weight gain and overall feed conversion ratio (FCR) than CON. Positive quadratic effects (P < 0.05) were noted for mean corpuscular hemoglobin, basophils, 24-hour breast meat yellowness, chroma, and hue angle. The GPA2 group had the lowest (P < 0.05) gait score while the CON group had the highest score. Concurrent supplementation with a 30 g RGP /kg diet plus 1% AVG in drinking water enhanced weight gain, FCR, and finisher weight of densely stocked broilers. However, AVG doses beyond 1% did not enhance performance and physiological traits in densely stocked broilers.

Extraction of phenolic compounds from grape pomace using ohmic heating: Chemical composition, bioactivity and bioaccessibility

This study addresses the effectiveness of ohmic heating technology (OH) for the sustainable recovery of phenolic compounds from Grape Pomace (GP) by hydroethanolic extraction. GP extracts biological potential was evaluated in terms of antioxidant activity, cytotoxicity and preventive effect against reactive oxygen species (ROS). To understand if GP extracts can be used as a functional ingredient, simulated gastrointestinal digestion was performed to evaluate the bioaccessibility. OH-assisted hydroethanolic extraction proved to be an effective process for the recovery of GP phenolic compounds with high antioxidant capacity. The digestion process increased the concentration of total phenolics and the biotransformation of high-molecular phenolics (anthocyanins, flavonoids and resveratrol) in simpler phenolic acids, improving bioaccessibility. GP extract displayed a selective action against cancer cells (Caco-2 and HeLa) and promoted ROS prevention. The results highlighted the ability of OH to extract bioactives from GP and its potential application as a nutraceutical or for functional food formulations.

Bioactive Components, Applications, Extractions, and Health Benefits of Winery By-Products from a Circular Bioeconomy Perspective: A Review

Significant waste streams produced during winemaking include winery by-products such as pomace, skins, leaves, stems, lees, and seeds. These waste by-products were frequently disposed of in the past, causing resource waste and environmental issues. However, interest has risen in valorizing vineyard by-products to tap into their latent potential and turn them into high-value products. Wine industry by-products serve as a potential economic interest, given that they are typically significant natural bioactive sources that may exhibit significant biological properties related to human wellness and health. This review emphasizes the significance of winery by-product valorization as a sustainable management resource and waste management method. The novelty of this review lies in its comprehensive analysis of the potential of winery by-products as a source of bioactive compounds, extraction techniques, health benefits, and applications in various sectors. Chemical components in winery by-products include bioactive substances, antioxidants, dietary fibers, organic acids, and proteins, all of which have important industrial and therapeutic applications. The bioactives from winery by-products act as antioxidant, antidiabetic, and anticancer agents that have proven potential health-promoting effects. Wineries can switch from a linear waste management pattern to a more sustainable and practical method by adopting a circular bioeconomy strategy. Consequently, the recovery of bioactive compounds that function as antioxidants and health-promoting agents could promote various industries concomitant within the circular economy.

On the evaluation of the antimicrobial effect of grape seed extract and cold atmospheric plasma on the dynamics of Listeria monocytogenes in novel multiphase 3D viscoelastic models

The demand for products that are minimally processed and produced in a sustainable way, without the use of chemical preservatives or antibiotics have increased over the last years. Novel non-thermal technologies such as cold atmospheric plasma (CAP) and natural antimicrobials such as grape seed extract (GSE) are attractive alternatives to conventional food decontamination methods as they can meet the above demands. The aim of this study was to investigate the microbial inactivation potential of GSE, CAP (in this case, a remote air plasma with an ozone-dominated RONS output) and their combination against L. monocytogenes on five different 3D in vitro models of varying rheological, structural, and biochemical composition. More specifically, we studied the microbial dynamics, as affected by 1 % (w/v) GSE, CAP or their combination, in three monophasic Xanthan Gum (XG) based 3D models of relatively low viscosity (1.5 %, 2.5 % and 5 % w/v XG) and in a biphasic XG/Whey Protein (WPI) and a triphasic XG/WPI/fat model. A significant microbial inactivation (comparable to liquid broth) was achieved in presence of GSE on the surface of all monophasic models regardless of their viscosity. In contrast, the GSE antimicrobial effect was diminished in the multiphasic systems, resulting to only a slight disturbance of the microbial growth. In contrast, CAP showed better antimicrobial potential on the surface of the complex multiphasic models as compared to the monophasic models. When combined, in a hurdle approach, GSE/CAP showed promising microbial inactivation potential in all our 3D models, but less microbial inactivation in the structurally and biochemically complex multiphasic models, with respect to the monophasic models. The level of inactivation also depended on the duration of the exposure to GSE. Our results contribute towards understanding the antimicrobial efficacy of GSE, CAP and their combination as affected by robustly controlled changes of rheological and structural properties and of the biochemical composition of the environment in which bacteria grow. Therefore, our results contribute to the development of sustainable food safety strategies.

Nonclinical evaluation of a Vitis vinifera extract towards a novel antiaging cosmetic ingredient

BACKGROUND

Skin aging is regulated by multiple physiological processes, such as oxidative stress. Natural products have been considered as a promising source of antioxidant compounds. As a result, few innovative products on the market based on natural products tackle additional underlying mechanisms of skin aging.

AIMS

The present work reports the nonclinical evaluation of a novel extract from the skin of V. vinifera fruits (codified as ACH37 extract), with the aim of supporting its use as an antiaging cosmetic ingredient candidate in clinical trials.

METHODS

We employed enzymatic, phenotypic, and gene expression assays, both in vitro and ex vivo, to investigate the action of the ACH37 extract in different biological processes that could be related to skin aging mechanisms.

RESULTS

The ACH37 extract was able to scavenge reactive oxygen species (DPPH, O2 - ), prevent inflammation (LPS- and UV-induced COX-2, IL-1β, and IL-8 expression), modulate extracellular matrix remodeling (inhibiting elastase, MMP-1, MMP-3, and MMP-12, as well as associated expression), increase telomere length, telomerase activity, and reverse the UV-induced suppression of genes involved in skin protection. In addition, the ACH37 extract permeated human skin explants and presented antioxidant efficacy ex vivo.

CONCLUSION

The results indicated that the ACH37 extract acts on multiple targets commonly related to skin aging, being a promising antiaging active ingredient candidate to be further investigated in clinical trials.

Joint effect of heat, pH and grape extract on Bacillus cereus spores survival in a rice solution

Rice due to its high carbohydrate content, is an ideal medium for Bacillus cereus growth, a spore-producing microorganism. The objective of this study was to determine the antimicrobial activity of a grape extract in combination with heat treatments and different pH against B. cereus spores in a rice solution. The survivor data obtained were fitted to the Weibull survival function, and the values of parameters a and b (scale and shape indexes, respectively) were determined. Results showed that the grape extract affected the survival of B. cereus spores at 90 °C and 95 °C, reaching greater logarithmic reductions in acidic pH values. This behaviour was reflected in a parameter of the Weibull survival function which decreased as the temperature increased and at acidic pH values. In addition, a secondary model was developed by relating the logarithm of a to the independent variables (temperature and pH). A global model relating B. cereus inactivation with temperature and pH was developed, and validated by calculating the accuracy factor. The results demonstrate the usefulness of grape extract as a by-product, which can be used as an additional control measure for rice, especially when combined with mild heat treatments and acidic pH values.

Fruit pomace as a promising source to obtain biocompounds with antibacterial activity

The demand for natural compounds to replace synthetic additives has aroused the interest of different sectors of society, especially the scientific community, due to their safety, biocompatibility, biodegradability and low toxicity. Alternative sources for antimicrobial compounds have been explored, such as fruit pomace. These by-products have essential compounds in their composition with different potential for application in food and packaging. In this context, this review systematizes the use of pomace from different fruits as a source of antibacterial compounds. Also, it summarizes the extraction methods and the applications of these compounds. Grape pomace, cranberry, and apple extracts are the most explored for antibacterial control, especially against genus Listeria, Salmonella, Staphylococcus, and Escherichia. In addition, phenolic acids, anthocyanins, flavonoids, and proanthocyanins are the main compounds identified in the studied fruit pomace extracts. In the reviewed articles, the biocompounds recovery is performed by methods with the absence of high temperatures (>80 °C); in some studies, the solid-liquid extraction method at mild temperatures (<30 °C) was well explored, using ethanol and water as solvent. The use of fruit processing by-products for bacterial control highlights the possibility of favoring the three pillars of sustainability (social, economic, and environmental) in the food industry.

Shoot Cultures of Vitis vinifera (Vine Grape) Different Cultivars as a Promising Innovative Cosmetic Raw Material-Phytochemical Profiling, Antioxidant Potential, and Whitening Activity

The primary purpose of this work was the initiation and optimization of shoot cultures of different Vitis vinifera L. cultivars: cv. Chardonnay, cv. Hibernal, cv. Riesling, cv. Johanniter, cv. Solaris, cv. Cabernet Cortis, and cv. Regent. Cultures were maintained on 30-day growth cycles using two media, Murashige and Skoog (MS) and Schenk and Hildebrandt (SH), with various concentrations of plant growth regulators. Tested media ('W1'-'W4') contained varying concentrations of 6-benzylaminopurine (BA) in addition to indole-3-butyric acid (IBA) and 1-naphthaleneacetic acid (NAA). High performance liquid chromatography coupled with mass spectrometry (UPLC-MS) was used for metabolomic profiling. In all tested extracts, 45 compounds were identified (6 amino acids, 4 phenolic acids, 13 flavan-3-ols, 3 flavonols, and 19 stilbenoids). Principal component analysis (PCA) was performed to assess the influence of the genotype and medium on metabolic content. PCA showed that metabolic content was mainly influenced by genotype and to a lesser extent by medium composition. MS media variants induced the amino acid, procyanidin, and flavan-3-ol production. In addition, the antioxidant potential and anti-tyrosinase activity was measured spectrophotometrically. The studies on antioxidant activity clearly reveal very high efficiency in reducing free radicals in the tested extracts. The strongest tyrosinase inhibition capacity was proved for shoots cv. Hibernal cultured in SH medium and supplemented with NAA, with an inhibition of 17.50%. These studies show that in vitro cultures of V. vinifera cvs. can be proposed as an alternative source of plant material that can be potentially used in cosmetic industry.

Functional, Physical, and Volatile Characterization of Chitosan/Starch Food Films Functionalized with Mango Leaf Extract

Active packaging is one of the currently thriving methods to preserve highly perishable foods. Nonetheless, the integration of active substances into the formulation of the packaging may alter their properties-particularly mass transfer properties-and therefore, the active compounds acting. Different formulations of chitosan (CH), starch (ST), and their blends (CH-ST), with the addition of mango leaf extract (MLE) have been polymerized by casting to evaluate their food preservation efficiency. A CH-ST blend with 3% MLE using 7.5 mL of the filmogenic solution proved to be the most effective formulation because of its high bioactivity (ca. 80% and 74% of inhibition growth of S. aureus and E. coli, respectively, and 40% antioxidant capacity). The formulation reduced the water solubility and water vapor permeability while increasing UV protection, properties that provide a better preservation of raspberry fruit after 13 days than the control. Moreover, a novel method of Headspace-Gas Chromatography-Ion Mobility Spectrometry to analyze the volatile profiles of the films is employed, to study the potential modification of the food in contact with the active film. These migrated compounds were shown to be closely related to both the mango extract additions and the film's formulation themselves, showing different fingerprints depending on the film.

Use of Winemaking By-Products for the Functionalization of Polylactic Acid for Biomedical Applications

The addition of naturally active compounds to implantable polymers is an efficient strategy against inflammation issues that might lead to rejection, while promoting controlled re-endothelialization of the tissues. This work proposes the use of winemaking by-products with high active properties of biomedical interest to obtain bioactive PLA by using supercritical technologies. First, two red grape pomace extracts, obtained by high-pressure extraction with supercritical CO₂ and cosolvents (either ethanol or water-ethanol), have been studied. Second, two impregnation methods have been studied with both extracts, traditional supercritical CO₂-assisted impregnation (SSI) and a novel pressurized soaking method (PSI). The amount of extract impregnated as well as the bioactivity levels achieved-i.e., antioxidant, antimicrobial, and anti-inflammatory properties- have been determined for each extract and impregnation method at different pressure and temperature conditions. Both extracts obtained had good antioxidant, anti-inflammatory, and antibacterial capacities, especially the hydroethanolic one (0.50 ± 0.03 mg TE/g versus 0.24 ± 0.03 mg TE/g, respectively). Regarding impregnated filaments, impregnation loadings depended especially on the extract and P/T conditions, providing up to 8% (extract mass/polymer mass) of impregnation. The antioxidant capacity increased noteworthily by using the ethanolic extract by PSI, with values near 100 µg TE/g PLA.

Antiherpetic Activity of Taurisolo®, a Grape Pomace Polyphenolic Extract

Herpes simplex virus (HSV) is widespread in the population, causing oral or genital ulcers and, rarely, severe complications such as encephalitis, keratitis, and neonatal herpes. Current available anti-HSV drugs are acyclovir and its derivatives, although long-term therapy with these agents can lead to drug resistance. Thus, the discovery of novel antiherpetic compounds merits additional studies. In recent decades, much scientific effort has been invested in the discovery of new synthetic or natural compounds with promising antiviral properties. In our study, we tested the antiviral potential of a novel polyphenol-based nutraceutical formulation (named Taurisolo^®) consisting of a water polyphenol extract of grape pomace. The evaluation of the antiviral activity was carried out by using HSV-1 and HSV-2 in plaque assay experiments to understand the mechanism of action of the extract. Results were confirmed by real-time PCR, transmission electron microscope (TEM), and fluorescence microscope. Taurisolo^® was able to block the viral infection by acting on cells when added together with the virus and also when the virus was pretreated with the extract, demonstrating an inhibitory activity directed to the early phases of HSV-1 and HSV-2 infection. Altogether, these data evidence for the first time the potential use of Taurisolo^® as a topical formulation for both preventing and healing herpes lesions.

Carotenoids Diet: Digestion, Gut Microbiota Modulation, and Inflammatory Diseases

Several epidemiologic studies have found that consuming fruits and vegetables lowers the risk of getting a variety of chronic illnesses, including several types of cancers, cardiovascular diseases (CVDs), and bowel diseases. Although there is still debate over the bioactive components, various secondary plant metabolites have been linked to these positive health benefits. Many of these features have recently been connected to carotenoids and their metabolites' effects on intracellular signalling cascades, which influence gene expression and protein translation. Carotenoids are the most prevalent lipid-soluble phytochemicals in the human diet, are found in micromolar amounts in human serum, and are very susceptible to multiple oxidation and isomerisation reactions. The gastrointestinal delivery system, digestion processes, stability, and functionality of carotenoids, as well as their impact on the gut microbiota and how carotenoids may be effective modulators of oxidative stress and inflammatory pathways, are still lacking research advances. Although several pathways involved in carotenoids' bioactivity have been identified, future studies should focus on the carotenoids' relationships, related metabolites, and their effects on transcription factors and metabolism.

Vitis vinifera (Vine Grape) as a Valuable Cosmetic Raw Material

This review refers to botanical, ecological and phytochemical characteristics of Vitis vinifera L. (vine grape)-a species, the valuable properties of which are widely exploited in the food industry and in recent times in medicine as well as in phytocosmetology. The general characteristic of V. vinifera, followed by the chemical composition and biological activities of different extracts obtained from the plant (fruit, skin, pomace, seed, leaf and stem extracts), are provided. A concise review of the extraction conditions of grape metabolites and the methods of their analysis are also presented. The biological activity of V. vinifera is determined by the presence of high contents of polyphenols, mainly flavonoids (e.g., quercetin, kaempferol), catechin derivatives, anthocyanins and stilbenoids (e.g., trans-resveratrol, trans-ε-viniferin). The review pays particular attention to the application of V. vinifera in cosmetology. It has been proven that V. vinifera possesses strong cosmetological-related properties, such as anti-ageing properties, anti-inflammatory properties and skin-whitening properties. Moreover, a review of studies on V. vinifera biological activities, which are of particular interest for dermatologic problems, are disclosed. Furthermore, the work also emphasises the importance of biotechnological studies on V. vinifera. The last part of the review is addressed to the safety of the use of V. vinifera.

Metabolomic profiling for the preventive effects of dietary grape pomace against colorectal cancer

Colorectal cancer (CRC) is one of the most common and deadly cancers worldwide. Grape pomace (GP) is a rich source of bioactive compounds with anti-inflammatory, and anticancer effects. We recently found that dietary GP had protective effects against CRC development in the azoxymethane (AOM)/dextran sulfate sodium (DSS) CRC mouse model through suppression of cell proliferation and modulation of DNA methylation. However, the underlying molecular mechanisms associated with changes in metabolites remain unexamined. This study profiled fecal metabolomic changes in a mouse CRC model in response to GP supplementation using gas chromatography-mass spectrometry (GC-MS) based metabolomic analysis. A total of 29 compounds showed significant changes due to GP supplementation, including bile acids, amino acids, fatty acids, phenols/flavonoids, glycerolipids, carbohydrates, organic acids, and others. The major changes in metabolites of feces include increased deoxycholic acid (DCA) and decreased amino acid content. Dietary GP upregulated the expression of farnesoid X receptor (FXR) downstream genes while decreasing fecal urease activity. DNA repair enzyme MutS Homolog 2 (MSH2) was upregulated by GP supplementation. Consistently, γ-H2AX, as a DNA damage marker, decreased in GP supplemented mice. Moreover, MDM2, a protein in the ataxia telangiectasia mutated (ATM) signaling, was decreased by GP supplementation. These data provided valuable metabolic clues for unraveling the protective effects of GP supplementation against CRC development.

A Systematic Quantitative Determination of the Antimicrobial Efficacy of Grape Seed Extract against Foodborne Bacterial Pathogens

Concerns regarding the role of antimicrobial resistance (AMR) in disease outbreaks are growing due to the excessive use of antibiotics. Moreover, consumers are demanding food products that are minimally processed and produced in a sustainable way, without the use of chemical preservatives or antibiotics. Grape seed extract (GSE) is isolated from wine industry waste and is an interesting source of natural antimicrobials, especially when aiming to increase sustainable processing. The aim of this study was to obtain a systematic understanding of the microbial inactivation efficacy/potential of GSE against Listeria monocytogenes (Gram-positive), Escherichia coli and Salmonella Typhimurium (Gram-negative) in an in vitro model system. More specifically, for L. monocytogenes, the effects of the initial inoculum concentration, bacterial growth phase and absence of the environmental stress response regulon (SigB) on the GSE microbial inactivation potential were investigated. In general, GSE was found to be highly effective at inactivating L. monocytogenes, with higher inactivation achieved for higher GSE concentrations and lower initial inoculum levels. Generally, stationary phase cells were more resistant/tolerant to GSE as compared to exponential phase cells (for the same inoculum level). Additionally, SigB appears to play an important role in the resistance of L. monocytogenes to GSE. The Gram-negative bacteria under study (E. coli and S. Typhimurium) were less susceptible to GSE as compared to L. monocytogenes. Our findings provide a quantitative and mechanistic understanding of the impact of GSE on the microbial dynamics of foodborne pathogens, assisting in the more systematic design of natural antimicrobial-based strategies for sustainable food safety.

Evaluation of the Phytochemistry-Therapeutic Activity Relationship for Grape Seeds Oil

Seeds' abundant biologically active compounds make them a suitable primary platform for the production of natural extracts, innovative foods, medicines, and cosmetics. High levels of industrial and agricultural residues and byproducts are generated during the processing of grapes, although some parts can also be repurposed. This paper examines the phytochemical composition, manufacturing processes, and health-improving attributes of many varieties of grape oil derived using various extraction methods. Since the results are influenced by a range of factors, they are expressed differently among studies, and the researchers employ a variety of measuring units, making it difficult to convey the results. The primary topics covered in most papers are grape seed oil's lipophilic fatty acids, tocopherols, and phytosterols. In addition, new methods for extracting grape seed oil should therefore be designed; these methods must be affordable, energy-efficient, and environmentally friendly in order to increase the oil's quality by extracting bioactive components and thereby increasing its biological activity in order to become part of the overall management of multiple diseases.

Molecular Fingerprinting and Microbiological Characterisation of Selected Vitis vinifera L. Varieties

The aim of the study was to analyse selected aspects of the natural variability of selected varieties of Vitis vinifera. Grapevine is one of the most popular and desirable crops in the world due to the great tradition of wine production, but grape extracts also have a wide range of pharmaceutical effects on the human body. It is important to identify different varieties for the conservation of genetic resources, but also for commercial and cultivation purposes. The variability of conserved DNA-derived polymorphism profiles, as well as microbial characteristics, were analysed in this study. Six different varieties of Vitis vinifera L. were used in the study: Cabernet Savignon, Chardonney, Welschriesling, Weisser Riesling, Gewurztramines and Gruner Veltliner. Genetic polymorphism was analysed by CDDP markers for WRKY genes. Polymorphic amplicon profiles were generated by all primer combinations used in the study. Gruner Veltliner and Welschriesling were the most similar, with a similarity value at 0.778. Microbiological quality of grape and antimicrobial activity against Gram-positive and Gram-negative bacteria and yeasts were analysed further. The plate diluting method for microbial quality and the disc diffusion method for antimicrobial activity were evaluated. The number of total count of bacteria ranged between 3.12 in Cabernet Sauvignon to 3.62 log cfu/g in Grűner Veltliner. The best antimicrobial activity showed Gewurztramines against Salmonella enterica, Yersinia enterocolitica, Pseudomonas aeroginosa, Staphylococcus aureus, Listeria monocytogenes, Candida albicans, Candida krusei, and Candida tropicalis. The best antimicrobial activity was found against Enterococcus faecalis in variety Weisser Riesling.

Protocorm-like-body extract of Phalaenopsis aphrodite combats watermelon fruit blotch disease

Bacterial fruit blotch, caused by the seedborne gram-negative bacterium Acidovorax citrulli, is one of the most destructive bacterial diseases of cucurbits (gourds) worldwide. Despite its prevalence, effective and reliable means to control bacterial fruit blotch remain limited. Transcriptomic analyses of tissue culture-based regeneration processes have revealed that organogenesis-associated cellular reprogramming is often associated with upregulation of stress- and defense-responsive genes. Yet, there is limited evidence supporting the notion that the reprogrammed cellular metabolism of the regenerated tissued confers bona fide antimicrobial activity. Here, we explored the anti-bacterial activity of protocorm-like-bodies (PLBs) of Phalaenopsis aphrodite. Encouragingly, we found that the PLB extract was potent in slowing growth of A. citrulli, reducing the number of bacteria attached to watermelon seeds, and alleviating disease symptoms of watermelon seedlings caused by A. citrulli. Because the anti-bacterial activity can be fractionated chemically, we predict that reprogrammed cellular activity during the PLB regeneration process produces metabolites with antibacterial activity. In conclusion, our data demonstrated the antibacterial activity in developing PLBs and revealed the potential of using orchid PLBs to discover chemicals to control bacterial fruit blotch disease.

Pomegranate Pomace Extract with Antioxidant, Anticancer, Antimicrobial, and Antiviral Activity Enhances the Quality of Strawberry-Yogurt Smoothie

Valorizing the wastes of the food industry sector as additives in foods and beverages enhances human health and preserves the environment. In this study, pomegranate pomace (PP) was obtained from the company Schweppes and exposed to the production of polyphenols and fiber-enriched fractions, which were subsequently included in a strawberry-yogurt smoothie (SYS). The PP is rich in carbohydrates and fibers and has high water-absorption capacity (WAC) and oil-absorption capacity (OAC) values. The LC/MS phenolic profile of the PP extract indicated that punicalagin (199 g/L) was the main compound, followed by granatin B (60 g/L) and pedunculagin A (52 g/L). Because of the high phenolic content of PP extract, it (p ≤ 0.05) has high antioxidant activity with SC50 of 200 µg/mL, besides scavenging 95% of DPPH radicals compared to ascorbic acid (92%); consequently, it reduced lung cancer cell lines' viability to 86%, and increased caspase-3 activity. Additionally, it inhibited the growth of pathogenic bacteria and fungi i.e., L. monocytogenes, P. aeruginosa, K. pneumonia, A. niger, and C. glabrata, in the 45-160 µg/mL concentration range while killing the tested isolates with 80-290 µg/mL concentrations. These isolates were selected based on the microbial count of spoiled smoothie samples and were identified at the gene level by 16S rRNA gene sequence analysis. The interaction between Spike and ACE2 was inhibited by 75.6%. The PP extract at four levels (0.4, 0.8, 1.2, and 1.4 mg/mL) was added to strawberry-yogurt smoothie formulations. During 2 months storage at 4 °C, the pH values, vitamin C, and total sugars of all SYS decreased. However, the decreases were gradually mitigated in PP-SYS because of the high phenolic content in the PP extract compared to the control. The PP-SYS3 and PP-SYS4 scored higher in flavor, color, and texture than in other samples. In contrast, acidity, fat, and total soluble solids (TSS) increased at the end of the storage period. High fat and TSS content are observed in PP-SYS because of the high fiber content in PP. The PP extract (1.2 and 1.6 mg/mL) decreases the color differences and reduces harmful microbes in PP-SYS compared to the control. Using pomegranate pomace as a source of polyphenols and fiber in functional foods enhances SYS's physiochemical and sensory qualities.

Improved Sustainability in Wine Industry Byproducts: A Scale-up and Economical Feasibility Study for High-Value Compounds Extraction Using Modified SC-CO2

The objective of the present work was to optimize the operating conditions (P, T cosolvent %) and to study the scale-up and the feasibility of the supercritical fluid extraction (SFE) process for polyphenols from grape pomace, the main solid byproduct of the wine industry. Pilot-scale equipment (1 L extraction vessel) was used to study the scale-up prediction for extraction vessels of 50, 100, 500, and 1000 L capacity. The adopted scale-up criteria consisted of maintaining and keeping constant the solvent mass-to-feed mass ratio and the bed geometry dimension. The results indicated an excellent predictive level obtained by Sovová's model and success of the adopted scale-up criteria. At industrial scale, yields were close to 2.3 g_GAE/100 g_DM, a value obtained using the pilot-scale equipment. High concentrations of high-added-value phenols such as cis-resveratrol glucoside, cis-coutaric acid, trans-p-coumaric acid, quercetin, and proanthocyanidins were found in the extract. An economic evaluation of the process indicated the feasibility of an industrial SFE plant with a capacity of 500 L for producing in 60 min an extract with an expected phenolics' concentration of approximately 133 g_GAE/kg _extract at an estimated 67€ /kg_extract cost of manufacturing. Notably, all values are better than those currently reported in the literature.

Increasing Value of Winery Residues through Integrated Biorefinery Processes: A Review

The wine industry is one of the most relevant socio-economic activities in Europe. However, this industry represents a growing problem with negative effects on the environment since it produces large quantities of residues that need appropriate valorization or management. From the perspective of biorefinery and circular economy, the winery residues show high potential to be used for the formulation of new products. Due to the substantial quantities of phenolic compounds, flavonoids, and anthocyanins with high antioxidant potential in their matrix, these residues can be exploited by extracting bioactive compounds before using the remaining biomass for energy purposes or for producing fertilizers. Currently, there is an emphasis on the use of new and greener technologies in order to recover bioactive molecules from solid and liquid winery residues. Once the bio compounds are recovered, the remaining residues can be used for the production of energy through bioprocesses (biogas, bioethanol, bio-oil), thermal processes (pyrolysis, gasification combustion), or biofertilizers (compost), according to the biorefinery concept. This review mainly focuses on the discussion of the feasibility of the application of the biorefinery concept for winery residues. The transition from the lab-scale to the industrial-scale of the different technologies is still lacking and urgent in this sector.

Development of highly stable color indicator films based on κ-carrageenan, silver nanoparticle and red grape skin anthocyanin for marine fish freshness assessment

Color indicator films for fish freshness were fabricated by incorporating κ-carrageenan (CAR) polymer with red grape skin extract (GSE) as a pH-sensing agent and silver nanoparticles (AgNPs) as an antimicrobial agent. Anthocyanins in GSE exhibited distinguished pH responsive color changes. GSE and AgNPs were well compatible with CAR with intramolecular interactions, approved by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis, thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC). GSE-containing films displayed distinguished color changes in response to pH variations and volatile ammonia. Enhanced UV blocking ability and strong antioxidant activity were revealed for GSE included films without sacrificing the physico-chemical properties of the CAR film. Films containing AgNPs showed improved mechanical strength and strong antimicrobial ability against both Escherichia coli and Staphylococcus aureus. The CAR/AgNPs/GSE film displayed a distinctive color change corresponding to changes in the total volatile basic nitrogen (TVB-N) of fish during storage. In addition, the CAR/AgNPs/GSE film showed excellent color stability to consecutive UV exposure and its storage time at 25 °C is expected to be at least 240 days, which indicates that it has high potential as an intelligent food freshness indicator film.

Chitosan Film Functionalized with Grape Seed Oil—Preliminary Evaluation of Antimicrobial Activity

Although the fishing and wine industries undoubtedly contribute significantly to the economy, they also generate large waste streams with considerable repercussions on both economic and environmental levels. Scientific literature has shown products can be extracted from these streams which have properties of interest to the cosmetics, pharmaceutical and food industries. Antimicrobial activity is undoubtedly among the most interesting of these properties, and particularly useful in the production of food packaging to increase the shelf life of food products. In this study, film for food packaging was produced for the first time using chitosan extracted from the exoskeletons of red shrimp (Aristomorpha foliacea) and oil obtained from red grape seeds (Vitis vinifera). The antimicrobial activity of two films was analyzed: chitosan-only film and chitosan film with the addition of red grape seed oil at two different concentrations (0.5 mL and 1 mL). Our results showed noteworthy antimicrobial activity resulting from functionalized chitosan films; no activity was observed against pathogen and spoilage Gram-positive and Gram-negative bacteria, although the antimicrobial effects observed were species-dependent. The preliminary results of this study could contribute to developing the circular economy, helping to promote the reuse of waste to produce innovative films for food packaging.

Effects of Time and Temperature on Stability of Bioactive Molecules, Color and Volatile Compounds during Storage of Grape Pomace Flour

Background: Grape pomace is highly attractive for the food industry as it contains numerous bioactive molecules relevant for human health. However, in order to exploit pomace flour as a functional food ingredient for food industry, it is important understand how long-term storage affects the stability of both bioactive molecules and volatile compounds, in addition to color. To this end, we analyzed whole pomace flour from red grape during a six-month storage period in the dark, either at 4 °C or 25 °C. Methods: The specific parameters monitored of grape pomace flour included: antioxidant activity (TEAC assay), total phenol content (Folin-Ciocalteu assay), phenol composition (high performance liquid chromatography), fatty acid composition (gas chromatography-mass spectrometry), volatile compound profiles (headspace-solid phase micro-extraction) and color. Results: Prolonged storage did not significantly affect total phenol content, antioxidant activity and characterized bioactive molecules (polyphenols, fatty acids). The only detected effect of storage was a slight whitening of the pomace flour and a small increase of volatile long chain esters and ketons after 6 months at 25 °C. Conclusions: The activity of several health-relevant bioactive compounds remained stable following storage of pomace flour for 6 months at 4 °C, supporting its possible use as a functional food ingredient.

Application of Citrus By-Products in the Production of Active Food Packaging

Some citrus by-products such as orange peel contains valuable compounds that could be recovered and restored into the food chain. In this study, an efficient valorization of orange peel has been investigated using green extraction, fractionation, and impregnation techniques. The first step included its extraction using CO2 and ethanol under different pressure (200–400 bar) and temperature (35–55 °C) conditions. The extracts obtained at 300 bar and 45 °C showed strong antioxidant with moderate antimicrobial activity. Then, the extract was subjected to a sequential fractionation process. The fraction obtained at 300 bar, 45 °C, and using 32% ethanol showed the strongest antioxidant and antimicrobial activity with a high extraction yield. Finally, the potential of the two best extracts (obtained at 400 bar and 45 °C before any fractionation and the fractions obtained at 300 bar, 45 °C using 32% ethanol) was determined by conducting an impregnation process to obtain an antioxidant food-grade rigid plastic that would preserve fresh food. The percentage of cosolvent (1 and 2% ethanol), the impregnation time (1 and 3 h), the pressure (200 and 400 bar), and the temperature (35 and 55 °C) were evaluated as variables of this process. The impregnated plastic showed good antioxidant and antimicrobial activities.

Towards the Optimization of Microwave-Assisted Extraction and the Assessment of Chemical Profile, Antioxidant and Antimicrobial Activity of Wine Lees Extracts

Wine lees, a sub-exploited byproduct of vinification, is considered a rich source of bioactive compounds, such as (poly)phenols, anthocyanins and tannins. Thus, the effective and rapid recovery of these biomolecules and the assessment of the bioactive properties of wine lees extracts is of utmost importance. Towards this direction, microwave-assisted extraction (MAE) factors (i.e., extraction time, microwave power and solvent/material ratio) were optimized using experimental design models in order to maximize the (poly)phenolic yield of the extracts. After optimizing the MAE process, the total phenolic content (TPC) as well as the antiradical, antioxidant and antimicrobial activity of the extracts were evaluated. Furthermore, Fourier transform infrared spectroscopy (FTIR) was employed to investigate the chemical profile of wine lees extracts. Red varieties exhibited higher biological activity than white varieties. The geographical origin and fermentation stage were also considered as critical factors. The white variety Moschofilero presented the highest antioxidant, antiradical and antimicrobial activity, while Merlot and Agiorgitiko samples showed noteworthy activities among red varieties. Moreover, IR spectra confirmed the presence of sugars, amino acids, organic acids and aromatic compounds. Thus, an efficient, rapid and eco-friendly process was proposed for further valorization of wine lees extracts.

Novel Clotrimazole and Vitis vinifera loaded chitosan nanoparticles: Antifungal and wound healing efficiencies

Chitosan integrated nanoparticles of clotrimazole and Egyptian Vitis vinifera juice extract was evaluated in order to maximize the antifungal activity and reduce the gross side effects. In the present study Egyptian Thompson Seedless Vitis vinifera and Clotrimazole (Cz) loaded chitosan nanoparticles (NCs/VJ/Cz) showed a promising antifungal effect with average inhibition zone diameters of 74 and 72 mm against Candida albicans and Aspergillus niger respectively. NCs/VJ /Cz was stable with significant drug entrapment efficiency reached 94.7%; PDI 0.24; zeta potential value + 31 and average size 35.4 nm diameter. Ex vivo and in vivo evaluation of skin retention, permeation and wound repair potentialities of NCs/VJ /Cz ointment was examined by experimental rats with wounded skin fungal infection. Data proved the ability of NCs/VJ /Cz to gradually release the drugs in a sustained manner with complete wound healing effect and tissue repair after 7 days administration. As a conclusion NCs/VJ /Cz ointment can be used as a novel anti-dermatophytic agent with high wound healing capacity.

Ensiling Grape Pomace With and Without Addition of a Lactiplantibacillus plantarum Strain: Effect on Polyphenols and Microbiological Characteristics, in vitro Nutrient Apparent Digestibility, and Gas Emission

The present study investigated the effects of different grape pomace storage techniques on the effectiveness as feed on in vitro ruminant digestion efficiency. Grape pomace from an autochthonous red grape variety (cv Nero di Troia) was used as fresh (GP) or ensiled, both without additives (SIL) and with the addition of a bacterial strain, Lactiplantibacillus plantarum 5BG (SIL+). All the different storage treatments were subject to chemical and microbiological evaluation, as well as in vitro digestibility, and gas production. Microbiological data revealed the good quality of grape pomace and silages due to the lactic acid bacteria populations and low presence, or absence, of undesirable microorganisms. The addition of L. plantarum 5BG influenced the chemical characteristics of the silage (SIL+). Ensiling technique deeply changed the polyphenolic composition, reducing anthocyanins, flavonols, and flavanols (condensed tannins precursors), particularly when L. plantarum 5BG was added. Antioxidant capacity was reduced by ensiling, in correlation with the polyphenolic content decrease. The oxygen radical absorbance capacity (ORAC) value of SIL+ was the lowest (P < 0.01) and its total phenol content was lower than SIL (P < 0.01). No statistical differences were observed between GP, SIL, and SIL+ on the antioxidant capacity by TEAC assay (P > 0.05). Ensiling did not affect the grape pomace nutrient profile, except for the reduction in NFC content. Apparent in vitro digestibility showed how ensiling increased dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), crude protein (CP), ether extract (EE), and non-fiber carbohydrates (NFC) disappearance (P < 0.01), particularly with the L. plantarum 5BG inoculation. Moreover, SIL+ showed the lowest propionic acid (P < 0.05) and the highest methane (P < 0.01), butyric acid (P < 0.01), and nitrogen (P < 0.05) in vitro production. Ensiling GP resulted in a better in vitro digestibility, particularly if L. plantarum 5BG strain is added, probably due to the reduction of flavanols and their lower microbial activity inhibition.

A Potential Valorization Strategy of Wine Industry by-Products and Their Application in Cosmetics-Case Study: Grape Pomace and Grapeseed

Grape pomace and grapeseed are agro-industrial by-products, whose inadequate treatment generates socioeconomic and environmental concerns. Nevertheless, it is possible to valorize them by extracting their bioactive compounds, such as antioxidants (phenolic compounds), vitamin E and fatty acids. The bioactive compounds were extracted using solid-liquid extraction. The yields for phenolic compounds were 18.4 ± 0.4% for grape pomace, and 17.4 ± 0.4%, for grapeseed. For the oil, the yields were 13.3 ± 0.2% and 14.5 ± 0.3% for grape pomace and grapeseed. Antioxidant capacity was assessed by the assay with 2,2-diphenyl-1-picrylhydrazyl (DPPH), and showed that phenolic extract has higher antioxidant capacity than the oils. Grape pomace and grapeseed extracts exhibit, correspondingly, values of 90.8 ± 0.8 and 87.5 ± 0.5 of DPPH inhibition and IC₅₀ of 48.9 ± 0.5 and 55.9 ± 0.7 μg_extract·mL_DPPH⁻¹. The antimicrobial capacity was assessed by the disk diffusion test, and revealed that, phenolic extracts inhibit the growth of Staphylococcus aureus and Staphylococcus epidermidis. The obtained extracts were incorporated in 10 face cream formulations, with slight modifications in quantities of formulation stabilizers. Their stability was studied for 35 days, and this revealed the possibility of incorporating extracts and oils obtained from by-products as antioxidants in cosmetics, and replacing synthetic ones. As a future recommendation, microencapsulation of the extracts should be performed, in order to increase their stability.

Syrah Grape Skin Residues Has Potential as Source of Antioxidant and Anti-Microbial Bioactive Compounds

Simple Summary

The aim of this study was to verify the influence of different extraction parameters (temperature and ultrasound time) of bioactive compounds from the skin of the Syrah variety of grape. Among the extracts obtained, those exposed to 20 min of sonication had the best results in terms of flavonoid content, antioxidant potential and phenolic profile. The temperature of 60 °C provided the most relevant results for the content of total phenolics, stilbenes, flavonols and phenolic acids, however, the association of this temperature with the use of ultrasound showed lower results as a source of antioxidant and antimicrobial bioactive compounds.

Abstract

In this study, we evaluated the effects of ultrasound-assisted extraction (UAE) under different time-temperature conditions on the content of bioactive compounds, antioxidant and antimicrobial activities of Syrah grape skin residue. The application of UAE showed a positive effect on the extraction of total flavonoids, and a negative effect on total polyphenols. The temperature of 40 °C and 60 °C without the UAE caused an increase of 260% and 287% of the total polyphenols, respectively. Nineteen individually bioactive compounds were quantified. The anthocyanin concentration (malvidin-3,5-di-O-glucoside 118.8–324.5 mg/100 g) showed high variation, to a lesser extent for phenolic acids, flavonoids, flavonols, procyanidins and stilbenes due to the UAE process. The Syrah grape skin residue has a high concentration of total phenolic compounds of 196–733.7 mg·GAE/100 g and a total flavonoid content of 9.8–40.0 mg·QE/100 g. The results of free radical scavenging activity (16.0–48.7 mg/100 mL, as EC₅₀) and its inhibition of microbial growth (0.16 mg/mL, as EC₅₀ for S. aureus, and 0.04 mg/mL, as EC₅₀ for E. coli) by grape skin extract (UAE 40:20) indicate high antioxidant and antibacterial activity. It was concluded that the use of ultrasound needs further analysis for its application in this context, as it has shown deleterious effects on some compounds of interest. Syrah grape skin residue has potential as a source of bioactive antioxidants, antimicrobial activity and for use as a functional food ingredient.

Composition and Biological Activity of Vitis vinifera Winter Cane Extract on Candida Biofilm

Vitis vinifera canes are waste material of grapevine pruning and thus represent cheap source of high-value polyphenols. In view of the fact that resistance of many pathogenic microorganisms to antibiotics is a growing problem, the antimicrobial activity of plant polyphenols is studied as one of the possible approaches. We have investigated the total phenolic content, composition, antioxidant activity, and antifungal activity against Candida biofilm of an extract from winter canes and a commercially available extract from blue grapes. Light microscopy and confocal microscopy imaging as well as crystal violet staining were used to quantify and visualize the biofilm. We found a decrease in cell adhesion to the surface depending on the concentration of resveratrol in the cane extract. The biofilm formation was observed as metabolic activity of Candida albicans, Candida parapsilosis and Candida krusei biofilm cells and the minimum biofilm inhibitory concentrations were determined. The highest inhibition of metabolic activity was observed in Candida albicans biofilm after treatment with the cane extract (30 mg/L) and blue grape extract (50 mg/L). The composition of cane extract was analyzed and found to be comparatively different from blue grape extract. In addition, the content of total phenolic groups in cane extract was three-times higher (12.75 g_GA/L). The results showed that cane extract was more effective in preventing biofilm formation than blue grape extract and winter canes have proven to be a potential source of polyphenols for antimicrobial and antibiofilm treatment.

Anthocyanin Recovery from Grape by-Products by Combining Ohmic Heating with Food-Grade Solvents: Phenolic Composition, Antioxidant, and Antimicrobial Properties

Usually, wine-making by-products are discarded, presenting a significant environmental impact. However, they can be used as a source of bioactive compounds. Moreover, consumers’ increasing demand for naturally nutritious and healthy products requires new formulations and food product improvement, together with sustainable, environmentally friendly extraction methods. Thus, this work aimed to compare ohmic heating (OH) with conventional methodology (CONV), using food-grade solvents, mainly water, compared to standard methanol extraction of anthocyanins. No significant differences were found between the CONV and OH for total phenolic compounds, which were 2.84 ± 0.037 and 3.28 ± 0.46 mg/g DW gallic acid equivalent, respectively. The same tendency was found for antioxidant capacity, where CONV and OH presented values of 2.02 ± 0.007 g/100 g and 2.34 ± 0.066 g/100 g ascorbic acid equivalent, respectively. The major anthocyanins identified were malvidin-3-O-acetylglucoside, delphinidin-3-O-glucoside, petunidine-3-O-glucoside, cyanidin-3-O-glucoside, and peonidine-3-O-glucoside. These extracts displayed antimicrobial potential against microorganisms such as Yersinia enterocolitica, Pseudomonas aeruginosa, Salmonella enteritidis, methicillin-sensitive Staphylococcus aureus, a methicillin-resistant Staph. aureus (MRSA), and Bacillus cereus. In conclusion, OH provides similar recovery yields with reduced treatment times, less energy consumption, and no need for organic solvents (green extraction routes). Thus, OH combined with water and citric acid allows a safe anthocyanin extraction from grape by-products, thus avoiding the use of toxic solvents such as methanol, and with high biological potential, including antimicrobial and antioxidant activity.

Grape Canes from Typical Cultivars of Campania (Southern Italy) as a Source of High-Value Bioactive Compounds: Phenolic Profile, Antioxidant and Antimicrobial Activities

The purpose of the current study was to determine the phenolic composition, antioxidant, and antimicrobial activities in grape cane extracts from typical cultivars of Southern Italy. Aqueous extracts at different pHs (1-13) were prepared from "Aglianico", "Fiano", and "Greco" grape canes. The results demonstrated that an alkaline pH (13.00) produced the best polyphenol-rich extracts, as the total phenolic content was more than double when compared to the respective extracts prepared at pH 1.00. "Greco" grape canes gave the highest quantity of phenolic compounds at each pH, ranging from 42.7 ± 0.4 to 104.3 ± 3.0 mg Gallic Acid Equivalents (GAE)/g Dry Extract (DE) from pH 1.00 to 13.00. The Radical Scavenging Activity (RSA) and the Ferric Reducing Antioxidant Power (FRAP) were measured. The highest antioxidant activity was showed by "Greco" extract at pH 7.00. Seventy-five compounds were identified in the extracts by HPLC-MS with six of them described for the first time in grape canes. Procyanidins were highly abundant in extracts at pH 7.00, whereas stilbenoids were the most represented compounds at pH 13.00. Very strong antiviral activity against herpes simplex viruses was recorded for the extracts at pH 7.00 and 13.00 that were active in the early stages of infection by acting directly against the viral particles. The overall results suggest that grape canes, currently underutilized, can be usefully valorised by providing active extracts to use as antioxidant and antiviral agents.

Use of Grape Peels By-Product for Wheat Pasta Manufacturing

Grape peels (GP) use in pasta formulation represents an economic and eco-friendly way to create value-added products with multiple nutritional benefits. This study aimed to evaluate the effect of the GP by-product on common wheat flour (Triticum aestivum), dough and pasta properties in order to achieve the optimal level that can be incorporated. Response surface methodology (RSM) was performed taking into account the influence of GP level on flour viscosity, dough cohesiveness and complex modulus, pasta color, fracturability, chewiness, cooking loss, total polyphenols, dietary fibers and resistant starch amounts. The result show that 4.62% GP can be added to wheat flour to obtain higher total polyphenols, resistant starch and dietary fiber contents with minimum negative effects on pasta quality. Flour viscosity, dough cohesiveness, complex modulus and pasta fracturability of the optimal sample were higher compared to the control, while chewiness was lower. Proteins' secondary structures were influenced by GP addition, while starch was not affected. Smooth starch grains embedded in a compact protein structure containing GP fiber was observed. These results show that GP can be successfully incorporated in wheat pasta, offering nutritional benefits by their antioxidants and fiber contents, without many negative effects on the final product's properties.

Valorization of Winemaking By-Products as a Novel Source of Antibacterial Properties: New Strategies to Fight Antibiotic Resistance

The emergence of antibiotic-resistance in bacteria has limited the ability to treat bacterial infections, besides increasing their morbidity and mortality at the global scale. The need for alternative solutions to deal with this problem is urgent and has brought about a renewed interest in natural products as sources of potential antimicrobials. The wine industry is responsible for the production of vast amounts of waste and by-products, with associated environmental problems. These residues are rich in bioactive secondary metabolites, especially phenolic compounds. Some phenolics are bacteriostatic/bactericidal against several pathogenic bacteria and may have a synergistic action towards antibiotics, mitigating or reverting bacterial resistance to these drugs. Complex phenolic mixtures, such as those present in winemaking residues (pomace, skins, stalks, leaves, and especially seeds), are even more effective as antimicrobials and could be used in combined therapy, thereby contributing to management of the antibiotic resistance crisis. This review focuses on the potentialities of winemaking by-products, their extracts, and constituents as chemotherapeutic antibacterial agents.

Effect-Directed Profiling of 17 Different Fortified Plant Extracts by High-Performance Thin-Layer Chromatography Combined with Six Planar Assays and High-Resolution Mass Spectrometry

An effect-directed profiling method was developed to investigate 17 different fortified plant extracts for potential benefits. Six planar effect-directed assays were piezoelectrically sprayed on the samples separated side-by-side by high-performance thin-layer chromatography. Multipotent compounds with antibacterial, α-glucosidase, β-glucosidase, AChE, tyrosinase and/or β-glucuronidase-inhibiting effects were detected in most fortified plant extracts. A comparatively high level of antimicrobial activity was observed for Eleutherococcus, hops, grape pomace, passiflora, rosemary and Eschscholzia. Except in red vine, black radish and horse tail, strong enzyme inhibiting compounds were also detected. Most plants with anti-α-glucosidase activity also inhibited β-glucosidase. Green tea, lemon balm and rosemary were identified as multipotent plants. Their multipotent compound zones were characterized by high-resolution mass spectrometry to be catechins, rosmarinic acid, chlorogenic acid and gallic acid. The results pointed to antibacterial and enzymatic effects that were not yet known for plants such as Eleutherococcus and for compounds such as cynaratriol and caffeine. The nontarget effect-directed profiling with multi-imaging is of high benefit for routine inspections, as it provides comprehensive information on the quality and safety of the plant extracts with respect to the global production chain. In this study, it not only confirmed what was expected, but also identified multipotent plants and compounds, and revealed new bioactivity effects.

The Application of Supercritical Fluids Technology to Recover Healthy Valuable Compounds from Marine and Agricultural Food Processing By-Products: A Review

Food by-products contain a remarkable source of bioactive molecules with many benefits for humans; therefore, their exploitation can be an excellent opportunity for the food sector. Moreover, the revalorization of these by-products to produce value-added compounds is considered pivotal for sustainable growth based on a circular economy. Traditional extraction technologies have several drawbacks mainly related to the consumption of hazardous organic solvents, and the high temperatures maintained for long extraction periods which cause the degradation of thermolabile compounds as well as a low extraction efficiency of desired compounds. In this context, supercritical fluid extraction (SFE) has been explored as a suitable green technology for the recovery of a broad range of bioactive compounds from different types of agri-food wastes. This review describes the working principle and development of SFE technology to valorize by-products from different origin (marine, fruit, vegetable, nuts, and other plants). In addition, the potential effects of the extracted active substances on human health were also approached.

Development of collagen/nanohydroxyapatite scaffolds containing plant extract intended for bone regeneration

In this study scaffolds of nanohydroxyapatite (nHA) and anionic collagen (C) combined with plant extracts intended for bone tissue repair were developed. Grape seed (P), pomegranate peel (R) and jabuticaba peel (J) extracts were used as collagen crosslinker agents in order to improve the materials properties. All crude extracts were effective against Staphylococcus aureus, but only for CR scaffold inhibition zone was noticed. The extracts acted as crosslinking agents, increasing enzymatic resistance and thermal stability of collagen. The extracts showed cytotoxicity at the concentrations tested, while nHA increased cell viability. The scaffolds presented porosity and pore size appropriate for bone growth. CR, CnHAP, CnHAR and CnHAJ increased the cell viability after 24 h. The combination of collagen, nHA and plant extracts offers a promising strategy to design novel biomaterials for bone tissue regeneration.

Antibacterial mechanisms of Aronia melanocarpa (Michx.), Chaenomeles superba Lindl. and Cornus mas L. leaf extracts

The aim of this study was to investigate the in vitro antibacterial mechanisms of Aronia melanocarpa, Chaenomeles superba, and Cornus mas leaf extracts towards meat spoilage and pathogenic bacteria. The extracts decreased bacterial viability after 24 h and 48 h of incubation. Acting as prooxidants, the extracts induced intracellular ROS (reactive oxygen species) generation in bacteria cells, with C. mas having the strongest influence. The leaf extracts increased the release of UV intracellular absorbing components, suggesting a reduction in membrane integrity. They also increased the outer-membrane permeability of the Gram-negative bacteria, with C. superba extract being the most active. Following exposure to the leaf extracts, morphological changes in the bacteria were observed, including the formation of aggregates, EPS synthesis, irregular forms, wrinkled cell surfaces, pores in the cell wall, and shriveling of cells. The leaf extracts inhibited DNA synthesis in E. coli cells by suppressing DNA gyrase activity.

Bioactive Compounds from Vine Shoots, Grape Stalks, and Wine Lees: Their Potential Use in Agro-Food Chains

The winemaking sector is one of the most productive worldwide, and thus it also generates large amounts of by-products with high environmental impacts. Furthermore, global market trends and government regulations promote industrial alternatives based on sustainable production processes. As a result, several studies have focused their attention on the reuse of grape by-products in the agro-food chain. Vine shoots, grape stalks, and wine lees, although produced to a lesser extent than grape pomace, have increasingly been receiving attention for their applications in the food sector, since they are a good source of functional and bioactive compounds. In this framework, our review highlights the promising results obtained by exploiting the antioxidant and/or antimicrobial activity of vine shoots, grape stalks, and wine lees or their extracts to replace the most common oenological additives and to assay the activity against food pathogens. Further, innovative functional foods and sustainable food packaging have been formulated by taking advantage of polyphenols and fiber, as well as plant bio-stimulants, in order to obtain grapes and wines with high quality characteristics. Overall, these by-products showed the potential to be recycled into the food chain as functional additives for different products and applications, supporting the sustainability of the winemaking sector.

Encapsulated Pine Bark Polyphenolic Extract during Gastrointestinal Digestion: Bioaccessibility, Bioactivity and Oxidative Stress Prevention

Polyphenolic extracts from pine bark have reported different biological actions and promising beneficial effects on human health. However, its susceptibility to environmental stresses (temperature, storage, etc.) and physiological human conditions prequires the development of efficient protection mechanisms to allow effective delivering of functionality. The aim of this work was to encapsulate pine bark extract rich phenolic compounds by spray-drying using maltodextrin, and understand the influence of encapsulation on the antioxidant and antimicrobial activity and bioaccessibility of phenolic compounds during gastrointestinal digestion. The optimized process conditions allowed good encapsulation efficiency of antioxidant phenolic compounds. The microencapsulation was effective in protecting those compounds during gastrointestinal conditions, controlling their delivery and enhancing its health benefits, decreasing the production of reactive oxygen species implicated in the process of oxidative stress associated with some pathologies. Finally, this encapsulation system was able to protect these extracts against acidic matrices, making the system suitable for the nutritional enrichment of fermented foods or fruit-based beverages, providing them antimicrobial protection, because the encapsulated extract was effective against Listeria innocua. Overall, the designed system allowed protecting and appropriately delivering the active compounds, and may find potential application as a natural preservative and/or antioxidant in food formulations or as bioactive ingredient with controlled delivery in pharmaceuticals or nutraceuticals.

Application of a Natural Antioxidant from Grape Pomace Extract in the Development of Bioactive Jute Fibers for Food Packaging

There is an increasing demand for the use of new food packaging materials. In this study, natural jute fibers impregnated with a Petit Verdot Red Grape Pomace Extract (RGPE) was proposed as a new active food packaging material. Pressurized Liquid Extraction (PLE) and Enhanced Solvent Extraction (ESE) techniques were employed to obtain the bioactive RGPE. Afterward the supercritical solvent impregnation conditions to obtain RGPE-natural jute fibers were studied, by varying pressure, modifier percentage and dried RGPE mass. PLE technique offered the highest bioactive extract at 20 MPa, 55 °C, 1 h residence time using C₂H₅OH:H₂O (1:1 v/v), providing an EC50 of 3.35 ± 0.25 and antibacterial capacity against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa (MIC of 12.0, 1.5 and 4.0 mg/mL RGPE respectively). The natural jute fibers impregnated with 3 mL of that RGPE (90 mg/mL) at 50 MPa and 55 °C generated the most efficient packing material with regards to its food preservation potential.