TOTAL PROTEIN PROFILE OF THALASSIOSIRA SP. IN DIFFERENT GROWTH PHASES

• Main Author: NUR KAMIL NIM:10511061, AHMAD
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/25195
• Institution: Institut Teknologi Bandung

Protein is one of the polypeptide compounds that have an important role in cell metabolism of living things. Research on carbohydrates, lipids and antioxidant compounds of Thalassiosira sp. has been reported. However, research on the Thalassiosira sp. isn’t done. The purpose of this research is to find the optimum condition of Thalassiosira sp. cells to producing proteins. The research started with Thalassiosira sp. cultivation, biomass measurement, thermal stability test, functional group characterization and biochemical morphology, then extraction and determination of protein content in Thalassiosira sp. by Bradford and Kjedahl method. Thalassiosira sp. which had been cultivated for 4 days and 9 consecutive days was 3.84 × 106 and 6.98 × 106 cells/mL with dry biomass yield from wet biomass of 10.69 and 10.47% (w/w) respectively . The analysis of thermal gravimetry showed decomposed dry biomass at a temperature of 150–520 0C of 34.59% (w/w) derived from organic compound components. The yield obtained in biosilica extraction was 2.34% from wet biomass. The FTIR test proves that the biomassa has been washed and has a Si–O–Si bond at a wavelength of 1073 cm-1. The SEM characterization describes the biosilica morphology is capsule with SiO2 composition is 94.2% (w/w) through the EDS test. The concentration of cell protein by the freeze-dried concentration method was 19.4% (w/w) in the exponential phase and 15.7% (w/w) in the stationary phase, and by the method of concentration with trichloroacetic acid was 18.5 (%w/w) in the exponential phase and 14.1% (w/w) in the stationary phase. While the result of total cell protein content in exponential and stationary phase were 22.1% (w/w) and 17.9% (w/w) respectively. So it can be concluded that the highest protein content obtained at the exponential growth stage.