## 4 Discussion  
Bioactive components isolated from microalgae have been studied against asthma, diabetes, viral infections, inflammation, and cancer [17,18]. Cancer represents a globally distributed disease, whose early diagnosis is critical to finding a treatment for its control or elimination [19]. The cancer treatment of choice is based on chemical drugs, radiotherapy, or tumor removal by surgery. However, several reports reveal the presence of other types of cancer that develop resistance, metastasis, or in some cases, cancer might reemerge [20]. The search for new natural compounds with antitumor activity is an important alternative for cancer control therapy, to avoid the presence of side effects or sequelae generated by the treatments of choice. The anticancer effect of _Ch. sorokiniana_ has been reported only for crude extracts and against murine L5178Y-R lymphoma cells. In the present study, we used the human cell line MCF-7, evaluated the cytotoxic, antioxidant, and hemolytic activities of collective fractions, and identified major compounds in CFs that showed the highest antioxidant and cytotoxic effects. Furthermore, the strain tested (UTEX 1239) was obtained from an industrialized process and its anticancer properties had not been previously evaluated. We showed that the _Ch. sorokiniana_ UTEX 1230 crude methanol extracts possessed a significantly higher antitumor effect (IC\({}_{50}\) = 209.9 \(\pm\) 1.14 \(\mu\)g/mL) against L5178Y-R cells than that (IC\({}_{50}\) = 460 \(\mu\)g/mL) of _Ch. sorokiniana_ isolated in Nuevo Leon, Mexico [2]. Other studies have shown that this species of microalgae inhibited the growth of cancer cell lines, different from those used in our work [8,21]. In this regard, mixotrophically cultured on glucose _Ch. sorokiniana_ TH01 strain lutein was reported to possess antitumor properties against human KB, HepG2, MCF-7, and SK-LU-1, showing IC\({}_{50}\) values of 58.07, 61.37, 71.52, and 81.69 \(\mu\)g/mL, respectively [7]. After the evaluation of _Ch. sorokiniana_ ethanol extract against human melanoma A375 and cervical cancer HeLa, another study demonstrated a decrease in their viability, using concentrations above 100 \(\mu\)g/mL, and in the case of A375, an IC\({}_{50}\) of 41.49 \(\mu\)g/mL was observed [22]. These studies evidenced the potential of using _Ch. sorokiniana_ extracts against cancer. In the present study, after fractionating and characterizing the _Ch. sorokiniana_ methanol extract, we detected metabolites that were previously reported to have anticancer or antioxidant activities, such as loligolide [23]. This compound, extracted from freshwater algae, reduced the expression of caspases 3, 8, and 9 in human keratinocytes, which are related to apoptosis induced by reactive oxygen species (ROS). Similarly, a loliglide isolated from _Sargassum horneri_ stimulated the HaCat keratinocytes and improved keratinocyte cell viability by reducing ROS production [24]. \begin{table}
\begin{tabular}{c c c c c} \hline  & & **Collective Fraction** & & \\ \hline
**CF3 and CF4** & **Detected Compound** & **Theoretical Mass** & **Chemical Class** & **Biological Activity a** \\ \hline CF3 & Loliglide & 197.117 & Benzofurans & Anticancer, antibacterial, antioxidant \\ CF3 and CF4 & Cinnamic acid & 149.059 & Humic acids and derivatives & Anticancer, antioxidant \\ CF4 & Methyl dihydrojasmonate & 227.164 & Fatty acids & Anticancer \\  & Sansalvamide A & 600.411 & Carboxylic acids and derivatives & Anticancer \\ CF4 & 1-monolinolenine & 353.268 & Fatty acyls & Anticancer \\  & Cryptophycin 29 & 625.267 & Peptidomimetics & Antitumor \\  & Costunolide & 233.153 & Prenl lipids & Anticancer \\  & Riboflavin luncirome & 243.087 & Pteridines and derivatives & Anticancer \\ \hline \end{tabular}  
* [[https://pubchem.ncbi.nlm.nih.gov](https://pubchem.ncbi.nlm.nih.gov)]([https://pubchem.ncbi.nlm.nih.gov](https://pubchem.ncbi.nlm.nih.gov)), accessed on 22 June 2024.  
\end{table} 
Table 4: Characterized metabolites from collective fractions CF3 and CF4, with anticancer activity.