Chemometric Optimization of Biologically Active Compounds Extraction from Grape Marc: Composition and Antimicrobial...

Area of Science:

• Food Chemistry
• Natural Product Chemistry
• Microbiology

Background:

• Grape marc, a wine industry byproduct, is rich in bioactive compounds.
• Efficient extraction of these compounds is crucial for valorization.
• Understanding extraction parameters is key to maximizing yield and bioactivity.

Purpose of the Study:

• To optimize the extraction of bioactive compounds (BAC) from grape marc.
• To investigate the impact of temperature and ethanol concentration on extraction yield.
• To characterize the extracts' chemical composition, antioxidant, and antimicrobial activities.

Main Methods:

• Extraction of bioactive compounds using varying temperatures (30-65 °C) and ethanol concentrations (0-96%).
• Analysis of polyphenols, flavonoids, anthocyanins, organic acids, and antioxidant activity (DPPH, ABTS).
• In vitro testing of grape marc extracts (GME) against pathogenic microorganisms (e.g., *Staphylococcus aureus*, *Escherichia coli*).

Main Results:

• Extraction parameters significantly influenced total polyphenol content (TPC), total flavonoid content (TFC), tannin content (TC), and total anthocyanin content (TAC).
• Grape marc extracts contained diverse flavonoids, hydroxybenzoic acids, and malvidol-3-glucoside as the main anthocyanin.
• Extracts exhibited significant antimicrobial activity against Gram-positive bacteria and moderate activity against Gram-negative bacteria.

Conclusions:

• Optimized extraction conditions can maximize the recovery of valuable bioactive compounds from grape marc.
• Grape marc extracts possess potent antioxidant and antimicrobial properties, suggesting potential applications.
• This study provides a mathematical model for predicting extraction yields based on process parameters.