biopigment, microalgae, productivity, nitrogen deficient, Nitzschia closterium

• 主要作者: Annisa, Bunga
• 格式: Final Project
• 語言: Indonesia
• 主題: Kimia
• 在線閱讀: https://digilib.itb.ac.id/gdl/view/32198
• 機構: Institut Teknologi Bandung

Biopigment is a natural dye, which is applied in a variety of fields ranging from health, beverage, and energy. The alternative source of biopigment is microalgae, photosynthetic microorganism with a fast growth rate and simple nutritional requirements. The purposes of this research were to identify the biopigment contents and to examine biopigment productivities on tropical marine microalgae Nitzschia closterium in two growth media conditions. In this research, N. closterium was cultivated in two different nitrogen media. Crude extract of biopigments were isolated from microalgae dried-biomass by using acetone. Purification of the biopigments were carried out by using silica column chromatography. Biopigment characterizations were conducted by using thin layer chromatography (TLC) and visible spectrophotometry. Biopigment productivity of N. closterium culture were determined by calculating the chlorophyll and carotenoid contents. N. closterium cells cultured under normal condition of nitrogen showed a better development in terms of cell size, cell density and cell growth compare to cultures under the nitrogen deficiency condition. The average cell density of N. closterium at the normal conditions was 1.3×106 cells/ mL, 2.51 g/ L which is obtained on the sixth day and for the nitrogen deficiency conditions was 0.978×106 cells/ mL, 2.01 g/ L for 4 day. Eight main visible biopigment from each growth media condition were identified by TLC. Several purified biopigments were identified as ?-carotene (426.5, 450 and 478.5 nm), chlorophyll a (411.5, 430, and 662 nm), chlorophyllide a (411, 431 and 462 nm), chlorophyll c (441, 577.5, and 627 nm) and fucoxanthin (444.5 and 468.5 nm). The total biopigment productivities for normal and nitrogen deficiency conditions were 7.99 and 3.92 mg/g in the dry weight. The results suggested that the nitrogen deficiency condition on N. closterium leads to reduce biopigment leves, but increase the ratio of [carotene]/[chlorophyll].