Gelatin Extracted from Rahu (Labeo rohita) and Silver Carp (Hypophthalmichthys molitrix) Scales and their Beads Efficacy as a Carrier of Inoculum and Secondary Metabolites

Abstract

The amount of biological waste is increasing day by day due to over population. At the same time, the researchers are striving to use biological waste in an effective way and to convert this waste into useful products. In this study, the scales of rohu (Labeorohita) and silver carp (Hypophthalmichthysmolitrix) were used for the extraction of gelatin. Chemical extraction method was applied in the presence and absence of microbes respectively to obtain gelatin from varying amount of scales. Microbial isolates namely SCC5 from silver carp and SEY from Labeorohita were used for microbial extraction. Beads were prepared from the extracted gelatin using three different types of oils and later used as carriers of inoculum. The results showed that both isolates were positive for gelatin liquefaction and did not result in solidification, evenwhen kept in the refrigerator at low temperature. The amount of the extracted gelatin from fish scales was less than 50%. A pronounced increase was recorded when more than 30 grams of fish scales were used for extraction. It was noticed that beads prepared with natural gelatin remained stable after washing and were not degraded as compared to commercial gelatin. FTIR analysis of the extracted gelatin showed the presence of peaks at 700, 1600, and 3400 nm. The recorded peaks were in line with the peak trend of commercial gelatin. Beads were coated with an antibiotic by soaking in the antibiotic dilution. Keeping in view the zones of the formation of beads supplemented with antibiotics, it was observed that zone diameter increased as the amount of antibiotic increased. It indicates that the beads have the capacity to carry the antibiotics. Moreover, t For this purpose, the beads of extracted gelatin were injected with a different inoculum of bacterial isolatesgelatin beads allow them to be used as carriers of fertilizers in agriculture, which is a recent advancement in the field of agriculture.