Chemical analyses and in vitro and in vivo toxicity of fruit methanol extract of Sechium edule var. nigrum spinosum

Abstract

Context: Sechium edule (Jacq.) Sw. (Cucurbitaceae) is used in ethnomedicine, but the diversity of the varietal groups of this species has not often been considered. This is important because we previously reported that different variety of species exhibit different activities across different tumor cell lines.

Objective: This study investigates the chemical composition and biological activities of extracts obtained from S. edule var. nigrum spinosum.

Materials and methods: The leukemia P388 cell line and mononuclear bone marrow cells (MNCBMs) were treated with the extract at a concentration ranging from 40 to 2370 μg/mL for cytotoxicity and viability assays. CD-1 mice were treated with 8–5000 mg/kg extract and monitored every hour for the first 24 h and subsequently for seven days for signs of toxicity (LD₅₀). In addition, the chromatographic profile of the extract was determined by HPLC.

Results: The extract inhibits the proliferation of both P388 cells and MNCBMs, with IC₅₀ values of 927 and 1911 μg/mL, respectively, but reduced the viability and induced the apoptosis of only leukemia cells. The LD₅₀ was higher than 5000 mg/kg, and this concentration did not alter the blood chemistry or cell count but doubled the mitotic index in the bone marrow. The HPLC showed the presence of cucurbitacins, phloridzin, naringenin, phloretin, apigenin, and gallic, chlorogenic, vanillic, p-hydroxybenzoic, caffeic, and p-coumaric acids.

Discussion and conclusion: Sechium edule var. nigrum spinosum contains bioactive compounds that explain the antiproliferative and nutraceutical activities, and its lack of physiological side effects constitutes an added value to a widely consumed vegetable.

Keywords:

• GISeM
• chayote
• cytotoxicity
• differential
• HPLC

Acknowledgements

The authors sincerely thank Adriana Altamirano Bautista, head of the Animal Facility of FES-Zaragoza, UNAM; Román Hernández Meza for his technical assistance with the animal care; Rubén San Miguel Chávez, a researcher in the Phytochemistry Area of the Colegio de Posgraduados, for handling the HPLC; and Taide Laurita Arista Ugalde and Ana Rocío Rivera Martínez for the technical assistance provided. Finally, we want to specially thank GISeM for the kind donation of S. edule var. nigrum spinosum.

Disclosure statement

There are neither any conflicts of interests nor any financial interests in this study from the part of the contributing authors that could inappropriately influence the work.