The Yemeni Brown AlgaeDictyota dichotomaExhibit HighIn VitroAnticancer Activity Independent of Its Antioxidant Capability

Abstract

e aim of this study was to investigate the anticancer and antioxidant activities as well as the safety of the brown algae Dictyota dichotoma of the Western seacoast of Yemen. Cytotoxicity of methanol extract of D. dichotoma and several of its fractions, petroleum ether, chloroform, ethyl acetate, n-butanol, and aqueous extracts against seven different cancer cell lines was determined by crystal violet staining. e antioxidant activity was also assessed using the DPPH radical scavenging assay. Acute toxicity study was performed on rats at increasing doses of the methanol extract. Extracts of D. dichotoma exerted a significant dose-dependent cytotoxicity on the seven tumor cell lines but were generally more selective on MCF-7 and PC-3. Among all fractions, the chloroform fraction of the D. dichotoma displayed the highest cytotoxic activity and was most effective in MCF-7, PC3, and CACO cells (IC 50 � 1.93 ± 0.25, 2.2 ± 0.18, and 2.71 ± 0.53 μg/mL, respectively). e petroleum ether fraction was also effective, particularly against MCF-7 and PC-3 (IC 50 � 4.77 ± 0.51 and 3.93 ± 0.51 μg/mL, respectively) whereas the activity of the ethyl acetate fraction was more pronounced against HepG2 and CACO (IC 50 � 5.06 ± 0.21 and 5.06 ± 0.23 μg/mL, respectively). Of all the extracts tested, the crude methanolic extract of the algae exhibited only a modest antioxidant potential (IC 50 � 204.6 ± 8.3 μg/mL). Doses as high as 5000 mg/kg body weight of D. dichotoma methanolic extracts were safe and well tolerated by rats. e overall results showed that D. dichotoma exhibited a significant cytotoxic activity probably due to the occurrence of nonpolar cytotoxic compounds, which is independent of its antioxidant capability.

The Biodiversity of the Genus Dictyota: Phytochemical and Pharmacological Natural Products Prospectives

“…Of all the extracts tested, the crude methanolic extract of the algae exhibited the best antioxidant potential (IC 50 = 204.6 ± 8.3 µg/mL). Doses as high as 5000 mg/kg body weight of D. dichotoma methanolic extracts were safe and well tolerated by rats [42].…”

Characteristic Volatile Composition of Seven Seaweeds from the Yellow Sea of China

“…Considering other pathways such as small cell lung cancer, non-small cell lung cancer, retrograde endocannabinoid signaling and PI3K–Akt signaling, we supposed that D. dichotoma may have certain preventive and therapeutic value in cancer, especially in lung cancer. The non-polar fractions of D.dichotoma exhibit anticancer activity in vitro, including the lung adenocarcinoma cell line (A-549) [ 33 ].…”

“…Considering other pathways such as small cell lung cancer, non-small cell lung cancer, retrograde endocannabinoid signaling and PI3K-Akt signaling, we supposed that D. dichotoma may have certain preventive and therapeutic value in cancer, especially in lung cancer. The non-polar fractions of D. dichotoma exhibit anticancer activity in vitro, including the lung adenocarcinoma cell line (A-549) [33]. In addition, it should be noted that the neuroactive ligand-receptor interaction pathway is the most relevant pathway for VOCs in D. dichotoma, with nine target genes involved-CHRM1, CHRM2, CHRM3, CHRNA2, GABRA1, GABRA2, GABRA3, GABRA5 and ADRA1B.…”

Identifying seaweeds species of Chlorophyta, Phaeophyta and Rhodophyta using DNA barcodes

“…Whereas Dictyota dichotoma are known for hosting rich mycobiota diversity (Pasqualetti et al, 2020) and its anti-cancer potential (El-Shaibany et al, 2020). In recent years, genetic characterization of D. dichotoma under acidified ocean conditions receives special attention (Porzio et al, 2020).…”