Antiproliferative Effects of Carotenoids Extracted from Chlorella ellipsoidea and Chlorella vulgaris on Human Colon Cancer Cells

Abstract

The antiproliferative activity of carotenoids separated from marine Chlorella ellipsoidea and freshwater Chlorella vulgaris has been evaluated. HPLC analysis revealed that the main carotenoid from C. ellipsoidea was composed of violaxanthin with two minor xanthophylls, antheraxanthin and zeaxanthin, whereas the carotenoid from C. vulgaris was almost completely composed of lutein. In an MTT assay, both semipurified extracts of C. ellipsoidea and C. vulgaris inhibited HCT116 cell growth in a dose-dependent manner, yielding IC(50) values of 40.73 +/- 3.71 and 40.31 +/- 4.43 microg/mL, respectively. In addition, treatment with both chlorella extracts enhanced the fluorescence intensity of the early apoptotic cell population in HCT116 cells. C. ellipsoidea extract produced an apoptosis-inducing effect almost 2.5 times stronger than that of the C. vulgaris extract. These results indicate that bioactive xanthophylls of C. ellipsoidea might be useful functional ingredients in the prevention of human cancers.

Role of Zucchini and Its Distinctive Components in the Modulation of Degenerative Processes: Genotoxicity, Antigenotoxicity, Cytotoxicity and Apoptotic Effects

“…Lutein has an antiproliferative activity on HeLa, HCT116 and Hep2 cancer cell lines [66] [67] [68]. On the other hand, similar negative effects to ours were obtained by Fernández-Bedmar and Alonso-Moraga [15]when HL60 cells were treated with this carotenoid.…”

Carotenoid production from Chlorococcum littorale in photoautotrophic cultures with downstream supercritical fluid processing

“…Laboratory-scale experiments conducted by Kurano et al focused on the effect of CO 2 concentration on C. littorale growth and found that growth rate was highest at CO 2 concentrations of 2% in air and decreased at higher concentrations [9]. Considering our previous results [10], the growth inhibition in high CO 2 concentrations observed by Kurano et al [9] could be result of decreasing the HCO 3 -/CO 2 ratio, that is, increasing CO 2 concentrations in the media leading to both a decrease in concentration of HCO 3 -promoter and an increase in CO 2 inhibitor. Hu et al investigated the time evolution of the production of intracellular components such as carbohydrates, proteins, lipids and chlorophylls, but they did not focus on carotenoids [8].…”

“…Optical density at 750 nm (OD 750 ) was measured by a spectrophotometer (JASCO, V-570). Cell concentration X (g-dry weight/dm 3 ) at a given cultivation time was determined from the calibration curve between the available OD 750 and the cell concentration (g-dry weight/dm 3 ). Cell concentrations were determined by thermal dry weight method [20].…”

“…Some carotenoids have been shown to act as antioxidants in the human body that have been considered to lower cancer risks [1]. The human body cannot produce carotenoids and thus needs to obtain them from foods such as pink grapefruit, guava, watermelon and tomatoes [2] or plants such as microalgae [3]. Growing demands for carotenoids in the supplement market have lead to studies on producing microalgal cultures [4].…”

Biological activity of microalgae can be enhanced by manipulating the cultivation temperature and irradiance

“…The astaxanthin rich extract from H. pluvialis inhibit the growth of five cancer cell lines-HCT-116, HT-29, LS-174, WiDr and SW-480 [31]. Carotenoids from Chlorella ellipsoidea and Chlorella vulgaris also inhibit the proliferation of HCT-116 tumor cells with low values of the concentration, required for 50% inhibition (IC 50 of 40.73±3.71 and 40.31±4.43 μg mL -1 , respectively) [32]. Violaxanthin, a pigment isolated from Dunaliella tetriolecta, has a dose-dependent Table 1.…”