Optimization of Chondroitin Sulfate Extraction From Skate (Raja spp.) Cartilage Using Response Surface Methodology:...

Area of Science:

• Marine Biotechnology
• Biochemistry
• Biomaterials Science

Background:

• Skate cartilage is a sustainable by-product rich in chondroitin sulfate (CS).
• Enzymatic hydrolysis offers a method for extracting bioactive compounds from cartilage.
• Optimizing extraction conditions is crucial for maximizing yield and bioactivity.

Purpose of the Study:

• To optimize the enzymatic hydrolysis of skate cartilage using response surface methodology (RSM).
• To characterize the resulting extract, focusing on disaccharide composition.
• To evaluate the in vitro anti-inflammatory and chondroprotective potential of the optimized skate cartilage extract (SCE).

Main Methods:

• Enzymatic hydrolysis of skate cartilage using Alcalase and Protamex.
• Optimization of extraction parameters (enzyme concentration, hydrolysis time, hydrolysate-to-ethanol ratio) via RSM.
• Analysis of disaccharide composition using High-Performance Liquid Chromatography (HPLC).
• In vitro biological assays using RAW264.7 macrophages and SW1353 chondrocytes.

Main Results:

• RSM identified optimal conditions yielding a CS-rich extract, with ∆Di-6S as the principal disaccharide.
• SCE significantly reduced nitric oxide and pro-inflammatory cytokine (IL-1β, IL-6, TNF-α) levels in macrophages.
• SCE dose-dependently increased mRNA expression of aggrecan and type II collagen in chondrocytes.

Conclusions:

• RSM is effective for optimizing enzymatic extraction of bioactive compounds from skate cartilage.
• The optimized SCE exhibits significant anti-inflammatory properties by suppressing inflammatory signaling pathways.
• SCE demonstrates chondroprotective potential by promoting cartilage matrix gene expression, suggesting therapeutic applications.