Bioakumulasi Rodamina B dalam Serat Sutra Samia cynthia ricini

Abstract

Samia cynthia ricini silk fiber is easily cultivated in Indonesia. The method of dyeing silk fiber must be environmentally friendly, such as the method of bioaccumulation of dyes. This method has never been used on S. ricini silkworms. This study aims to identify the effect of rhodamine B on the characteristics of silk fiber and the productivity of S. ricini silkworm cultivation. Rhodamine B is used because it has a positive partition coefficient, is amphiphilic, and has a high lipophilicity. In this method, fifth instar S. ricini silkworm larvae were fed modified feed with rhodamine B at a concentration of 0–0.5% w/w. The addition of rhodamine B to the feed produced pink (λmax= 546 nm) and orange luminescence (λmax= 568 nm) cocoons and rhodamine B was distributed in the silk glands of the S. ricini silkworm. Silk fiber modified with rhodamine B has a tensile strength of 557 ± 66 MPa and an elongation of 19.18 ± 3.96%, fiber morphology with a diameter of 20.51 ± 1.60 µm, and an unchanged FTIR spectrum. The mortality of S. ricini modified rhodamine B silkworm larvae was 0–5.82% and the cocoon weight ranged from 1.21–2.02 g. These results indicate bioaccumulation of S. ricini silk fiber bioaccumulation does not affect fiber characteristics and cultivation productivity.