Effects of Culture Conditions on Growth and Biochemical Profile of Chlorella Vulgaris

Abstract

The effects of culture conditions at different temperature and light regimes on growth and the contents of chlorophyll-a, chlorophyll-b, total carotenoids, total protein and total free amino acids of Chlorella vulgaris were determined. The growth of C. vulgaris in terms of optical density (0.42 at 670 nm), cell count (440 x 104 cells/ml) and dry weight (30.2 mg/50 ml), and the amount of chlorophyll-a (2.16%), chlorophyll-b (0.59%) and total protein, was found higher at the temperature 25-30°C and natural day light receiving through the north facing window of the growth room. Although, the amount of total carotenoids (0.440%) and free amino acids (834 µg/gm fresh weight) were found maximum in continuous light at 30-35°C, not much differences in the amount of carotenoids (0.385%) and free amino acids (822 µg/gm fresh weight) were found at 25-30°C and natural day light. The natural day light at 25-30°C was also proved proficient, as distinct banding pattern with unique polypeptides such as 15KDa, 47KDa and 50KDa, on the other hand, 23KDa, 26KDa and 36KDa appeared in all samples, these bands were not affected by light and temperature. Our results indicate that among all five culture conditions tested, the cultures kept at north facing window receiving natural day light at temperature 25-30°C, show best growth and higher contents of biochemicals that will be beneficial to use Chlorella for high nutritive purpose. In order to find out the optimum culture condition, the cultures were subjected to five different conditions of temperature and light regimes. In the growth room, light was provided by fluorescent tube lights (40 W) having 2500 Lux intensity, and were fixed at a distance of 64 cm from the cultures in constant and alternate light conditions. One set of five different culture conditions were placed in the laboratory in window, which was facing north, for providing natural day and dark periods. The intensity of natural day light was as an average 2700 Lux. The following culture conditions set in the growth room were used in the present study: Effects of Culture Conditions on Growth and Biochemical Profile of Chlorella Vulgaris Rekha Growth measurement Estimation of pigmentsChlorophyll content of the samples were extracted in 90% (v/v) acetone, and chlorophyll-a, b estimated by Parson and Strickland method [14]. Carotenoid content of the samples were extracted in 80% (v/v) acetone, and estimated by Jensen method [15]. Estimation of proteinsProtein content of the samples was estimated quantitatively by Lowry [16] by dry biomass, using bovine serum albumin (BSA) as standard. Qualitatively, the proteins were estimated by the SDS-PAGE analysis, which was carried out according to Laemmli [17]. For extraction of proteins, the samples were homogenized with lysis buffer containing 0.5M Tris-HCl, 8M Urea, 5% (w/v) SDS, 20% (v/v) Glycerol and 10% (v/v) β-Mercaptoethanol; final pH 6.8 and centrifuged at 4°C for 20 min at 10,000 rpm. Protein extract was used for SDS-PAGE analysis, using a 12% polyacrylamide gel co...

Increasing the Protein Amount of Chlorella vulgaris [Chlorphyta] Strains Isolated from Different Fresh Water Ponds

“…Sostarie, M., et al [39] carried out a study on production of C. vulgaris with different carbon resources by using Jaworski medium and reported that the cell number rose to maximum (7.8 × 10 6 cell/mL) at the end of seventh day. Both the results obtained by Sharma, R., et al [38] and by Sostarie, M., et al [39] showed parallelism with the results obtained in the present study with regards to cell number and chlorophyll a. Although the dry weight results obtained by Sharma, R., et al [38] are found higher, it is supposed that this result stemmed from the characteristics of nutrient media and strains used.…”

“…Sharma, R., et al [38] reported cell density of C. vulgaris as 4.4 × 10 6 cells/mL, dry weight as 30.2 mg/50 mL and chlorophyll a amount as 2.16% under different temperatures and light regimes. Sostarie, M., et al [39] carried out a study on production of C. vulgaris with different carbon resources by using Jaworski medium and reported that the cell number rose to maximum (7.8 × 10 6 cell/mL) at the end of seventh day.…”

Utilization of Anaerobic Digestion Supernatant as a Nutrient Source in Microalgal Biomass Production with a Membrane Photobioreactor

“…This value was comparable with other research (1.57%) using Modified Chu-10 medium as culture medium [14].…”

Improvement of Nutrition Production by Protoplast Fusion Techniques in Chlorella vulgaris

“…The reduced growth seems affected the nutrition on microalgal cell exhibited by a low protein and higher carbohydrate content. These factor were determined in the study of Sharma et al [30] which showed that lower degree of illumination will favors higher protein in Chlorella. C. vulgaris and fusant exhibited 5% to 6% total lipid content.…”