Impact of Different Geographical Locations on Genetic Variation and Phytochemical Constituents of Two Medicinal Marine Algae.

Abstract

Genetic variations and phytochemical constituents of Dictyota dichotoma and Sargassum dentifolium, collected from Hurghada and Abu-Qir bay, were investigated. Results revealed an increase in the concentrations of carotenoids, sugars and DPPH% in the samples of both algal species collected from Hurghada as compared with those collected from Abu-Qir. Regarding the samples collected from Hurghada, an increase in the concentrations of chlorophyll a, b and phenols was recorded in S. dentifolium; while a decrease in chlorophyll a, b only was observed in D. dichotoma. No significant difference was observed in phenol concentrations between D. dichotoma samples collected from the two studied localities. DNA was isolated and thirteen SCoT molecular markers were used to detect the genetic variations between the samples of the two localities. In D. dichotoma, the total average of polymorphism is 56.68%. SCoT-1 exhibited the highest polymorphism (80%), while SCoT-28 recorded the lowest polymorphism (35.71%). In S. dentifolium, the total average of polymorphism is 61.63%. SCoT-3 showed the highest polymorphism (90%), while SCoT-13 exhibited the lowest polymorphism (0.09%). In addition, BSI factor showed a marked difference between the two studied algae that it was 0.87 % in D. dichotoma and 0.77 % in S. dentifolium. Variation in geographical location affects genetic variation and phytochemical composition of D. dichotoma and S. dentifolium. The difference in the responses of the two studied algae to the change of locality and environmental conditions may reflect differences in their gene expression. Moreover, the efficiency of SCoT markers to discriminate between algal species collected from different localities has been confirmed.

Semi-continuous system for benthic diatom cultivation and marennine production

“…ined., which thermal optimum is undoubtedly higher than that of other strains. Several studies have shown that the geographic locations or localities and also seasonal variations could affect the chemical composition and the production of bioactive compounds in algae [45,46]. However, in our study if the thermal optimum is respected, the EMn productivity seem not too much related to strain origin.…”