Shanab Sanaa M M, Mostafa Soha S M, Shalaby Emad A, Mahmoud Ghada I
Botany Department, Faculty of Science, Cairo University, 12613 Giza, Egypt.
Asian Pac J Trop Biomed. 2012 Aug;2(8):608-15. doi: 10.1016/S2221-1691(12)60106-3.
To investigate the antioxidant and anticancer activities of aqueous extracts of nine microalgal species.
Variable percentages of major secondary metabolites (total phenolic content, terpenoids and alkaloids) as well as phycobiliprotein pigments (phycocyanin, allophycocyanin and phycoerythrin) in the aqueous algal extracts were recorded. Antioxidant activity of the algal extracts was performed using 2, 2 diphenyl-1-picrylhydrazyl (DPPH) test and 2,2'- azino-bis (ethylbenzthiazoline-6-sulfonic acid (ABTS.(+)) radical cation assay. Anticancer efficiency of the algal water extracts was investigated against Ehrlich Ascites Carcinoma cell (EACC) and Human hepatocellular cancer cell line (HepG2).
Antioxidant activity of the algal extracts was performed using DPPH test and ABTS.(+) radical cation assays which revealed 30.1-72.4% and 32.0-75.9% respectively. Anticancer efficiency of the algal water extracts was investigated against Ehrlich Ascites Carcinoma Cell (EACC) and Human Hepatocellular cancer cell line (HepG2) with an activity ranged 87.25% and 89.4% respectively. Culturing the promising cyanobacteria species; Nostoc muscorum and Oscillatoria sp. under nitrogen stress conditions (increasing and decreasing nitrate content of the normal BG11 medium, 1.5 g/L), increased nitrate concentration (3, 6 and 9 g/L) led to a remarkable increase in phycobilin pigments followed by an increase in both antioxidant and anticancer activities in both cyanobacterial species. While the decreased nitrate concentration (0.75, 0.37 and 0.0 g/L) induced an obvious decrease in phycobilin pigments with complete absence of allophycocyanin in case of Oscillatoria sp.
Nitrogen starvation (0.00 g/L nitrate) induced an increase and comparable antioxidant and anticancer activities to those cultured in the highest nitrate content.
研究9种微藻水提取物的抗氧化和抗癌活性。
记录藻类水提取物中主要次生代谢物（总酚含量、萜类化合物和生物碱）以及藻胆蛋白色素（藻蓝蛋白、别藻蓝蛋白和藻红蛋白）的不同百分比。使用2,2-二苯基-1-苦基肼（DPPH）试验和2,2'-联氮-双-（3-乙基苯并噻唑啉-6-磺酸）（ABTS⁺）自由基阳离子测定法测定藻类提取物的抗氧化活性。研究藻类水提取物对艾氏腹水癌细胞（EACC）和人肝癌细胞系（HepG2）的抗癌效果。
使用DPPH试验和ABTS⁺自由基阳离子测定法测定藻类提取物的抗氧化活性，结果分别显示为30.1%-72.4%和32.0%-75.9%。研究藻类水提取物对艾氏腹水癌细胞（EACC）和人肝癌细胞系（HepG2）的抗癌效果，活性分别为87.25%和89.4%。培养有前景的蓝藻物种，即念珠藻和颤藻。在氮胁迫条件下（正常BG11培养基中硝酸盐含量增加和减少，1.5 g/L），增加硝酸盐浓度（3、6和9 g/L）导致藻胆色素显著增加，随后两种蓝藻物种的抗氧化和抗癌活性均增加。而硝酸盐浓度降低（0.75、0.37和0.0 g/L）导致藻胆色素明显减少，颤藻中完全没有别藻蓝蛋白。
氮饥饿（0.00 g/L硝酸盐）诱导的抗氧化和抗癌活性增加，与在最高硝酸盐含量下培养时相当。
