Lack of in vitro anticancer and antimicrobial activities from Karanda (Carissa carandas) fruit extracts

Abstract

Background: Carissa carandas L. (Apocynaceae), commonly known as Karanda, is a
widely used medicinal plant. In Thailand, Karanda fruits are favorite fruits especially
in central region due to attractive shape and color with health promoting activities.
Aims: To evaluate its antimicrobial and anticancer activities for claim promoting
activities. Cytotoxicity of extracts was also evaluated with normal cells to claim for health
safety. Materials and Methods: Anticancer activities of Karanda fruits extracted with
dichloromethane (KD) and methanol (KM) were performed by resazurin microplate
assay and tested with five cell lines, including KB-oral cavity cancer, MCF7-breast
cancer, NCI-H187-small lung cancer, HepG2-hepatocarcinoma, and Caco2-colon
adenocarcinoma cell lines. Cytotoxicity of KD and KM were performed as above and
used HDFn-neonatal dermal fibroblast as normal cells. Antimicrobial activities of KD
and KM against herpes simplex virus type I (HSV-1) and Mycobacterium tuberculosis
were tested according by green fluorescent protein-based assay; Candida albicans were
tested according to resazurin microplate assay, and Plasmodium falciparum K1 strain
was tested according to microculture radioisotope techniques. Results: Both extracts
were not possessed anticancer activity to any cancer cell lines at maximum concentration
= 100 µg/mL. In the same way to anticancer activity assays, both extracts were not
inhibited HSV-1, P. falciparum K1 strain, and M. tuberculosis (maximum concentration
= 50 µg/mL). Also, both extracts were nontoxic to normal cells. Conclusion: KD and
KM extracts of ripped Karanda fruits had no significant anticancer and antimicrobial
activities with noncytotoxicity.