The grape seed extract: a natural antimicrobial agent against different pathogens

Antibacterial effect of red laser-activated silver nanoparticles synthesized with grape seed extract against Staphylococcus aureus and Escherichia coli

Living organisms, particularly humans, frequently encounter microorganisms such as bacteria, fungi, and viruses in their surroundings. Silver nanoparticles are widely used in biomedical devices because of their antibacterial and antiviral properties. The study evaluates the efficacy of red laser and silver nanoparticles from grape seed extract (AgNPs-GSE) in reducing Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria, which cause infections. The sample comprised three groups: a control group without laser irradiation (T0), Escherichia coli samples (A1 and A2) irradiated with a 405-nm diode laser at different times and concentrations of silver nanoparticles, and Staphylococcus aureus samples (A3 and A4) illuminated with a 405-nm diode laser at different times and concentrations. Bacteria in groups A2 and A4 were treated with a photosensitizer (PS) made from grape seed extracts, incubated for 10 min, and then irradiated for 90, 120, 150, and 180 s. The samples were cultured on TSA media, set at 37 °C, counted using a Quebec colony counter, and analyzed using ANOVA and Tukey tests with a significance level of p < 0.05. The study illustrated that the combination of 10 µl of AgNPs-GSE, exposure to a red laser at 405 nm, and an energy density of 3.44 J/cm2 effectively photoinactivated both Escherichia coli and Staphylococcus aureus bacteria. For Escherichia coli bacteria irradiated for 180 s with concentrations of 1 mM, 1.5 mM, and 2 mM AgNPs-GSE, bacterial viability decreased by 64.50%, 70.74%, and 79.53%, respectively. Similarly, Staphylococcus aureus bacteria, subjected to irradiation for 180 s with concentrations of 1 mM, 1.5 mM, and 2 mM AgNPs-GSE, demonstrated reductions in bacterial viability by 70.23%, 73.47%, and 85.04%, respectively. The findings from the present study indicate that at an energy density of 3.44 J/cm2, it was possible to inactivate Escherichia coli by 79.53% and Staphylococcus aureus by 85.04%.

Direct microwave treatment enhances antioxidant and antibacterial properties of the seed extracts of Kékfrankos grapes

The Kékfrankos is the most frequently cultivated wine grape in Hungary, with a significant national and regional impact, resulting in considerable amounts of byproducts (e.g. pomace, seeds). To the best of our knowledge no research has been conducted on the antioxidant and antibacterial properties of its seed extracts (GSE). A novel apporach of applying direct microwave treatment on grape seeds was implemented for the first time to enhance antioxidant and antimicrobial properties of GSE. Antioxidant properties were assayed using the DPPH (2,2-diphenyl-1-picrylhydrazyl), FRAP (Ferric Reducing Antioxidant Power) and TPC (Folin-Ciocâlteu's Total Polyphenol Content) methods. Profile and content of polyphenols was studied using high-performance liquid chromatography/tandem mass spectrometry and matrix-assisted laser desorption/ionization mass spectrometry. Antibacterial properties were evaluated using Gram-positive Staphylococcus aureus (SA), methicillin-resistant Staphylococcus aureus (ST239) (MRSA) and Gram-negative Escherichia coli (EC) bacteria strains. Results proved that the mild direct microwave treatment of grape seeds significantly increased total polyphenol, (+)-catechin, (-)-epicatechin as well as antioxidant capacity levels by 20-30 % compared to untreated samples and resulted the best antibacterial properties based on bacterial growth curves (SA and MRSA: 0.015625 mg/mL, EC: 0.25 mg/mL). Results justify the importance of further pharmacological investigations on Kékfrankos grape seed extracts and that the direct microwave treatment of grape seeds is an innovative approach for the fast and cost efficient improvement of the antibacterial properties of grape seed extracts.

Combined Effect of Citric Acid and Polyphenol-Rich Grape Seed Extract towards Bioactive Smart Food Packaging Systems

Alginate films (2% w·v^-1) were prepared with varying concentrations (5-20% w/w) of citric acid and aqueous grape seed extract (GSE) filtrate (11.66 ± 1.32 g GAE/L) using the solvent-evaporation method. Crosslinking alginate via ester bonds (FTIR analysis) with citric acid up to 10% (w/w) led to a 33% increase in tensile strength, a 34% reduction in water vapor transmission rate (WVTR), and had no impact on elongation at break. Crosslinking alginate with citric acid in the presence of GSE increased the tensile strength by 17%, decreased WVTR by 21%, and significantly improved DPPH scavenging activity. Moreover, after incubation for 24 h at 37 °C, the film-forming solutions exhibited increased antimicrobial activity, resulting in 0.5- and 2.5-log reductions for Escherichia coli and Staphylococcus aureus, respectively, compared to the values obtained without the addition of GSE. The stronger inhibitory effect observed against Gram-positive bacteria can be attributed to the unique composition and structure of their cell walls, which creates a barrier that restricts the penetration of polyphenols into the cells. The pH adjustment of the GSE film-forming solution from 2.0 to 10.0 shifted the UV/VIS absorption spectra, resulting in a colour change from yellow to red. The findings of this study have showcased the potential of combining GSE and citric acid to enhance the functionality and bioactivity of alginate films for applications in smart food packaging.

Antibacterial and antioxidant double-layered nanofibrous mat promotes wound healing in diabetic rats

Diabetic wounds are problematic to heal owing to microbial infections as well as decreased proliferation and high concentrations of reactive oxygen species. In this study, a double-layered nanofibrous mat containing grape seed extract (GSE) and silver sulfadiazine (SSD) was fabricated. A synthetic biodegradable polymer, e.g., polycaprolactone (PCL), and a natural material (i.e., collagen) were employed as wound dressing substances. The results showed that GSE possesses antioxidant activity which can be helpful in reducing free radicals. The platform exhibited antibacterial activity against gram-positive and -negative bacteria. The double-layered nanofibrous mat containing GSE and SSD not only was not toxic but also amplified the cell proliferation compared to a pure mat, showing the effect of plant extract. After induction of a round wound, the animals were divided into three groups, namely (1) normal group (receiving + GSE/-GSE nanofiber), (2) diabetic group (receiving + GSE/-GSE nanofiber), and (3) control group (receiving gauze). In vivo evaluation demonstrated no significant differences in the healing process of normal rats. Surprisingly, fully repaired skin was observed on day 14 in the double-layered nanofibrous mat containing GSE in the normal and diabetic groups whereas the wound of diabetic rats treated with pure mat was not completely healed. The macroscopic and microscopic results after 14 days showed the following order in wound repair: Normal/ + GES > Diabetic/ + GSE > Normal/-GES > Diabetic/-GSE > control (with gauze) (p < 0.05). Accordingly, the double-layered nanofibrous mat containing GSE and SSD used in the present study could be considered as a suitable wound dressing in order to shorten healing time and prevent infection during the wound healing process.

Antimicrobial Potential, Antioxidant Activity, and Phenolic Content of Grape Seed Extracts from Four Grape Varieties

The aim of this study was to evaluate the total phenolic content, composition, and antioxidant and antibacterial activities of four grape seed extracts (Cabernet Sauvignon, Marselan, Pinot Noir, and Tamyanka). The total phenolic content (TPC) and flavonoid, anthocyanin, procyanidin, ascorbic acid, DPPH, and ABTS antioxidant capacities of the grape seed extracts (GSEs) were determined. The extracts showed high TPC values (79.06-111.22 mg GAE/g). The individual components in the GSEs were determined using HPLC. High contents of catechin, epicatechin, and procyanidin B1 were found in the extracts. The antimicrobial activity of the obtained GSEs against Staphylococcus aureus, Bacillus cereus, and Escherichia coli was evaluated using the agar diffusion test and a test to determine the minimum inhibitory concentration (MIC). According to the effect on the growth of pathogens, the extracts were ranked in the following order: Pinot Noir > Marselan > Cabernet Sauvignon > Tamyanka. The tested bacteria showed high sensitivity to the extracts (MIC = 0.12-0.50 mg/mL). According to the MIC values, the bacteria were in the following order: S. aureus > B. cereus > E. coli. A correlation was found between the phenolic content of the GSEs and their antibacterial potential. The obtained results show that the studied GSEs have good potential as antioxidant and antimicrobial agents.

Inactivation Mechanism and Efficacy of Grape Seed Extract for Human Norovirus Surrogate

Proper disinfection of harvested food and water is critical to minimize infectious disease. Grape seed extract (GSE), a commonly used health supplement, is a mixture of plant-derived polyphenols. Polyphenols possess antimicrobial and antifungal properties, but antiviral effects are not well-known. Here we show that GSE outperformed chemical disinfectants (e.g., free chlorine and peracetic acids) in inactivating Tulane virus, a human norovirus surrogate. GSE induced virus aggregation, a process that correlated with a decrease in virus titers. This aggregation and disinfection were not reversible. Molecular docking simulations indicate that polyphenols potentially formed hydrogen bonds and strong hydrophobic interactions with specific residues in viral capsid proteins. Together, these data suggest that polyphenols physically associate with viral capsid proteins to aggregate viruses as a means to inhibit virus entry into the host cell. Plant-based polyphenols like GSE are an attractive alternative to chemical disinfectants to remove infectious viruses from water or food. IMPORTANCE Human noroviruses are major food- and waterborne pathogens, causing approximately 20% of all cases of acute gastroenteritis cases in developing and developed countries. Proper sanitation or disinfection are critical strategies to minimize human norovirus-caused disease until a reliable vaccine is created. Grape seed extract (GSE) is a mixture of plant-derived polyphenols used as a health supplement. Polyphenols are known for antimicrobial, antifungal, and antibiofilm activities, but antiviral effects are not well-known. In studies presented here, plant-derived polyphenols outperformed chemical disinfectants (i.e., free chlorine and peracetic acids) in inactivating Tulane virus, a human norovirus surrogate. Based on data from molecular assays and molecular docking simulations, the current model is that the polyphenols in GSE bind to the Tulane virus capsid, an event that triggers virion aggregation. It is thought that this aggregation prevents Tulane virus from entering host cells.

Wound Dressing: Combination of Acacia Gum/PVP/Cyclic Dextrin in Bioadhesive Patches Loaded with Grape Seed Extract

The success of wound treatment is conditioned by the combination of both suitable active ingredients and formulation. Grape seed extract (GSE), a waste by-product obtained by grape processing, is a natural source rich in many phenolic compounds responsible for antioxidant, anti-inflammatory, and antimicrobial activities and for this reason useful to be used in a wound care product. Bioadhesive polymeric patches have been realized by combining acacia gum (AG) and polyvinylpyrrolidone (PVP). Prototypes were prepared by considering different AG/PVP ratios and the most suitable in terms of mechanical and bioadhesion properties resulted in the 9.5/1.0 ratio. This patch was loaded with GSE combined with cyclic dextrin (CD) to obtain the molecular dispersion of the active ingredient in the dried formulation. The loaded patch resulted mechanically resistant and able to release GSE by a sustained mechanism reaching concentrations able to stimulate keratinocytes’ growth, to exert both antibacterial and antioxidant activities.

The Antimicrobial Activities of Silver Nanoparticles from Aqueous Extract of Grape Seeds against Pathogenic Bacteria and Fungi

Grape seed extract (GSE) is a natural source of polyphenolic compounds and secondary metabolites, which have been tested for their possible antimicrobial activities. In the current study, we tested the antibacterial and antifungal activities of aqueous GSE and the biosynthesized silver nanoparticles loaded with GSE (GSE-AgNPs) against different pathogens. The biosynthesized GSE-AgNPs were assessed by UV spectroscopy, dynamic light scattering (DLS), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), and gas chromatography/mass spectrometry (GC/MS). The antimicrobial activities were assessed against different bacterial and fungal species. DLS analysis showed that GSE-AgNPs had a Z-Average of 91.89 nm while UV spectroscopy showed that GSE-AgNPs had the highest absorbance at a wavelength of ~415 nm. FTIR analysis revealed that both of GSE and GSE-AgNPs consisted of different functional groups, such as hydroxyl, alkenes, alkyne, and aromatic rings. Both FE-SEM and TEM showed that GSE-AgNPs had larger sizes and rough surfaces than GSE and AgNO₃. The results showed significant antimicrobial activities of GSE-AgNPs against all tested species, unlike GSE, which had weaker and limited effects. More studies are needed to investigate the other antimicrobial activities of GSE.

Incorporation of grape seed extract towards wound care product development

Naturally derived ingredients are becoming more prevalent in therapeutic drug formulations due to consumers' concerns about chemical side effects. In the context of wound care, despite the impressive progress in therapeutic product development, drugs dispensed to treat impaired healing challenged by biofilms; excessive inflammation and oxidation are not yet really effective. Thus, the hunts for improved drug formulations preferably using natural ingredients that are cost-effective in accelerating the wound-healing process are of constant demand. The grape seed extract is extensively studied and is reported to be rich in phenolic compounds, unsaturated fatty acids and vitamins which exhibit numerous therapeutic benefits owing to their anti-inflammatory, anti-microbial, and anti-oxidative properties that support its potential use in the development of wound-healing products. We conducted a literature study using Scopus, PubMed, and Google Scholar including the keywords "grape seed extract" and "wound healing". We also scanned all the references cited by the retrieved articles. Accordingly, this review is aimed to (i) explore the various phytochemical constituents found in grape seed extracts along with their mechanism of action that instigate wound healing, (ii) to highlight the latest pre-clinical and clinical assessments of grape seed extract in wound models, and (iii) to encourage innovation scientists in the field to address current limitations and to effectively develop grape seed extract-based wound care product formulations for commercialization.

A Comprehensive Study on the Antimicrobial Properties of Resveratrol as an Alternative Therapy

Resveratrol is a polyphenolic antioxidant whose possible health benefits include anticarcinogenic, antiaging, and antimicrobial properties that have gained significant attention. The compound is well accepted by individuals and has been commonly used as a nutraceutical in recent decades. Its widespread usage makes it essential to study as a single agent as well as in combination with traditional prescription antibiotics as regards to antimicrobial properties. Resveratrol demonstrates the action of antimicrobials against a remarkable bacterial diversity, viruses, and fungus. This report explains resveratrol as an all-natural antimicrobial representative. It may modify the bacterial virulence qualities resulting in decreased toxic substance production, biofilm inhibition, motility reduction, and quorum sensing disturbance. Moreover, in conjunction with standard antibiotics, resveratrol improves aminoglycoside efficacy versus Staphylococcus aureus, while it antagonizes the deadly function of fluoroquinolones against S. aureus and also Escherichia coli. The present study aimed to thoroughly review and study the antimicrobial potency of resveratrol, expected to help researchers pave the way for solving antimicrobial resistance.

Effect of vacuum impregnated fish gelatin and grape seed extract on moisture state, microbiota composition, and quality of chilled seabass fillets

The effect of fish gelatin (FG) and grape seed extract (GSE) on microbiota composition and moisture state of fish was unexplored. Herein, this study aimed to evaluate the single and combined (FGG) effects on seabass during storage (4 °C) with assistant of vacuum impregnation and to elucidate the underlying preservative mechanism. As suggested by low-field NMR and magnetic resonance imaging, FGG-treated seabass presented higher water holding capacity by controlling transformation from immobilised to free water. Moreover, the total viable count and spoilage bacteria were reduced by > 1 log CFU/g as compared to the control. Changes in microbial flora analysed using high throughput sequencing further indicated that GSE contributed to the notably suppressed growth of Pseudomonas. Also, the accumulation of biogenic amines especially putrescine was decreased (over 0.5-fold) under the combination treatment as compared to the control (P < 0.05). The results suggest that FGG is promising for seabass preservation.

Efficacy of grape seed hydro-alcoholic extract in the treatment of experimentally Pasteurella multocida infected rabbits

Pasteurellosis is one of the rabbit's most bacterial severe diseases and leads to considerable financial damages in large production systems worldwide. Antibiotic use in animals may lead to antibiotic residues in animal products, including meat. Therefore, this study was designed to evaluate the potential role of grape seed extract (GSE) in treating Pasteurella multocida infection in rabbits. For this purpose, 45 weaned male New Zealand rabbits were divided into three groups; control, infected and infected-GSE treated. Experimental P. multocida infection in rabbits induced a remarkable decrease in body weight, body weight gain, as well as microcytic hypochromic anaemia, leucocytosis, neutrophilia and lymphocytopenia. Also, a significant increase in the hepatic and renal injury biomarkers, in interleukin-6, total globulin, α, β and γ globulins, as well as a marked reduction in total protein and albumin, were recorded in the P. multocida-infected rabbits. Treatment of infected rabbits with GSE modulated most of these altered parameters. This study endorses the administration of GSE for the treatment of Pasteurellosis in rabbits. Further studies are required to identify the possible additional effects, appropriate doses and duration of the GSE therapy in rabbits Pasteurellosis.