The Characteristic Of Biocomposite Film Of Spirulina Residue As Natural Dyes

Abstract

Spirulina plantesis microalgae contain active ingredients in the form of antioxidants and pigments. Currently, the microalgae Spirulina plantesis is used as an antioxidant in the food, pharmaceutical and cosmetic industries. This manuscript discusses the utilization of Spirulina plantesis microalgae pigment as a natural dye plastic. The need for color plastics for various uses continues to increase. The use of natural dyes for plastics is expected to produce biocomposite films that are safe for the environment or biodegradable and safe to be used. The aim of the study was to determine the effect of adding Spirulina residue as a natural dye on the characteristics of biocomposite films. The variable concentration of Spirulina residue added to the biocomposite film formula was 0.5%,1%, and 1.5%. The film production method used was the solution casting method. In this study, 200ml of distilled water was added with Spirulina residue (SR), then stirred for 30 minutes, and after that successively added 1% Glycerol and stirred for 15 minutes; Carrageenan 1% and stirred for 15 minutes. The solution was heated at 70oC then Polyvinyl Alcohol (PVA) with concentrations of 3%, 4%, and 5%, and Tapioca (3%) were added until complete gelatinization occurred. The solution was poured into a 30 cm x 20 cm mold and dried at 30oC for 48 hours to form a film. Biocomposite films were analyzed for tensile strength and elongation at break based on ASTM D 638, color, and morphology. The results showed that the highest tensile strength and elongation at break of biocomposites were found in biocomposite films with the addition of 0.5% Spirulina residue, namely 96.40±6.04 kgf/m2 and 47.64±7.48%, respectively. Analysis of the color of the biocomposite films showed the highest greenish and yellowish colors in the biocomposite films with the addition of 1.5% Spirulina residue and 5% PVA. Spirulina residue can be utilized as the plastic dyes.