Agar from Red Algae (Gracilaria tenuistipitata) as a Valuable Biopolymer: Extraction and Characterization
DOI:
https://doi.org/10.47981/j.mijst.13(02)2025.536(27-38)Keywords:
Agar; Red Algae; Gracilaria tenuistipitata; Cox’z Bazar; Biomedical ApplicationAbstract
Agar, a natural biopolymer extracted from red algae, holds immense potential for revolutionizing healthcare, including biomedical engineering. This study explores the feasibility of extracting agar from red algae (Gracilaria tenuistipitata) abundantly available in the coastal area of Cox’z Bazar, Bangladesh. Five extraction methods were investigated, including control and treatments with water and NaOH solutions at 2%, 4%, and 6% concentrations. Each method was applied to three extraction cycles, producing 15 samples for comprehensive analyses. The extracted agar samples were characterized through Fourier-transform infrared spectroscopy (FTIR), gel strength testing, melting and gelling temperature assessments, pH value measurement, and sulfate content analysis to determine their suitability for potential biomedical applications. Statistical tools such as ANOVA and Tukey's HSD test were employed to evaluate the influence of the pretreatment process on the yield and characteristics of agar. The results revealed significant variations across methods, emphasizing the critical role of extraction conditions in determining agar yield and characteristics. Among different alkali treatment methods, the sample processed with 2% NaOH and two hours treatment provided the highest agar yield of 11.67 %. Thus, two hours treatment with 2% NaOH was determined to be the optimal condition for agar extraction. This preliminary study suggests that the red algae is a promising source of agar for wider applications, including biomedical engineering. The agar extracted from abundant local sources in Bangladesh could unlock its potential for advancing healthcare solutions and sustainable national economic growth.
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