A Comparative Study on Inhibition of Breast Cancer Cells and Tumors in Mice by Carotenoid Extract and Nanoemulsion Prepared from Sweet Potato (Ipomoea batatas L.) Peel

Abstract

The objectives of this study were to determine carotenoid composition in sweet potato (TNG66) peel and prepare carotenoid nanoemulsion to study its inhibition effect on breast cancer cells MCF-7 and tumors in mice. Results showed that a total of 10 carotenoids were separated within 30 min by employing a YMC C30 column and a gradient mobile phase of methanol/acetonitrile/water (74:14:12, v/v/v) and dichloromethane (B) with a flow rate of 1 mL/min, column temperature of 25 °C, and detection wavelength of 450 nm. Following quantitation, all-trans-β-carotene was present in the highest amount (663.8 μg/g). The method validation data demonstrated a high accuracy and precision of this method. The carotenoid nanoemulsion was prepared by mixing an appropriate proportion of carotenoid extract, Tween 80, PEG 400, soybean oil and deionized water with the mean particle size being 15.7 nm (transmission electron microscope (TEM)), polydispersity index 0.238, encapsulation efficiency 97% and zeta potential −69.8 mV. A high stability of carotenoid nanoemulsion was shown over a 90-day storage period at 25 °C and during heating at 100 °C for 2 h. The release percentage of total carotenoids from carotenoid nanoemulsion under gastric and intestinal condition was 18.3% and 49.1%, respectively. An antiproliferation study revealed that carotenoid nanoemulsion was more effective than carotenoid extract in inhibiting the growth of human breast cancer cells MCF-7. Following treatments of paclitaxel (10 μg/mL), carotenoid nanoemulsion (20 and 10 μg/mL) and carotenoid extract (20 and 10 μg/mL), the tumor weight of mice respectively decreased by 77.4, 56.2, 40.3, 36.1 and 18.7%, as well as tumor volume of mice by 75.4, 65.0, 49.7, 46.7 and 26.5%. Also, both carotenoid extract and nanoemulsion could reduce the levels of epidermal growth factor (EGF) and (vascular endothelial growth factor (VEGF) in serum, with the latter being more effective. This finding suggested that carotenoid nanoemulsion was more effective than carotenoid extract in inhibiting tumor growth in mice.

Quantification of Xanthone and Anthocyanin in Mangosteen Peel by UPLC-MS/MS and Preparation of Nanoemulsions for Studying Their Inhibition Effects on Liver Cancer Cells

“…For the preparation of nanoemulsions, highly unsaturated soybean oil was selected based on its abundance and low cost as well as its ability to protect bioactive compounds, as indicated by McClements and Jafari [ 32 ] and Hsu and Chen [ 33 ]. Moreover, various trial studies based on the calculation of HLB (hydrophilic–lipophilic balance) value were conducted to choose the appropriate surfactant/cosurfactant type and amount to stabilize the soybean oil containing xanthone or anthocyanin extract and obtain stable nanoemulsions.…”

“…For the proportion of G0/G1 phase, a significant decline ( p < 0.05) by 10.92, 11.41 and 13.58%, respectively, was found following treatment with the xanthone extract at 6, 8 and 10 μg/mL, as well as 17.17, 19.17 and 19.84% when treated with the xanthone nanoemulsion at the same doses. By comparison, xanthone nanoemulsion was more effective than xanthone extract in decreasing the proportion of the G0/G1 phase, probably caused by the enhanced permeation and retention (EPR) effect for easier penetration into cells [ 33 ]. Similar to the sub-G1 phase, a significant rise ( p < 0.05) in the S phase proportion by 1.48, 1.73 and 3.08%, respectively, was found for the xanthone extract at 6, 8 and 10 μg/mL, as well as 2.70, 3.11 and 3.21% for the xanthone nanoemulsion at the same doses, when compared to the control treatment.…”

Citrus Carotenoid Extracts Promote ROS Accumulation and Induce Oxidative Stress to Exert Anti-Proliferative and Pro-Apoptotic Effects in MDA-MB-231 Cells

“…Studies have shown that the combination of carotenoids at equimolar concentrations can inhibit the growth of cancer cells more effectively than individual carotenoids [ 32 ]. Another study also demonstrated that carotenoid extracts effectively inhibited the activity of MCF-7 human breast cancer cells and suppressed tumor growth in female BALB/c nude mice [ 46 ]. Russo M et al proposed that the carotenoid mixture exhibits a stronger inhibitory effect on MCF-7 cell proliferation, which may be attributed to its synergistic effect [ 47 ].…”

Lipid Nanoparticles: An Effective Tool to Improve the Bioavailability of Nutraceuticals

“…Whey protein and soy lecithin showed better results in the context of a smaller droplet size (<150 nm) and interfacial tension, which ultimately contributed to the improved stability of the carotenoid NE [110]. In a recent study, carotenoid NE produced a prominent antiproliferative effect in breast cancer cells (MCF-7) and tumor-bearing mice by virtue of considerable reduction in epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) levels compared to the carotenoid extract [111].…”