Preliminary study on monoculture establishment and growth assessment of three Chlorophyta microalgae from Shalimar Garden, Lahore, Pakistan

Freshwater microalgal samples were collected from Shalimar Garden, Lahore, Pakistan, and successfully cultured to establish pure monocultures. Three Chlorophyta species Chlorella ellipsoidea, Pediastrum obtusum, and Scenedesmus incrassatulus var. capitatus were taxonomically identified under an inverted microscope and selected for monoculture studies. Monocultures were maintained on Bold’s Basal Medium (BBM) and CHU-10 medium using the streaking technique. Peak biomass in fresh weight on BBM was recorded on the 18th day, reaching 2.12 g, 1.15 g, and 1.41 g for C. ellipsoidea, P. obtusum, and S. incrassatulus var. capitatus, respectively, with corresponding maximum growth rates of 0.004-0.009 g/day. In CHU-10, peak biomass and growth rates were notably lower (0.42-0.35 g; 0.001-0.003 g/day). By day 21, biomass and growth declined in both media, indicating nutrient depletion and onset of the decline phase. Net weight gains were substantially higher in BBM (1.38 g, 0.73 g, 0.94 g) compared to CHU-10 (0.34 g, 0.29 g, 0.26 g), and these differences were statistically significant (p<0.0001) demonstrating BBM’s superior performance in supporting faster growth and higher biomass accumulation. This study represents the first successful monoculturing of these three Chlorophyta species from the selected Shalimar Garden, Lahore, Pakistan, representing preliminary investigation thus providing baseline data that can guide future applied research in algal biotechnology and environmental studies.