Bitter gourd or Mara: A Free Radical Fighter
Bitter gourd (Momordica charantia L.) or Mara (in Thai) has long been used as a food and medicine (El Batran, El-Gengaihi, & El Shabrawya, 2006). Bitter gourd is called by different names since it grows in tropical regions such as India, Malaya, China, tropical Africa, MiddleEast, America (Kirtikar & Basu, 1993) and Thailand. As a medicinal plant, it has been reported to possess antilipolytic, analgesic, abortifacient, antiviral, cytotoxic, hypoglycemic and antimutagenic properties (Singh, Singh, & Bamezai, 1998). Extract powder of fresh and dried whole fruit of bitter gourd lowered blood sugar in diabetic rats, as reported by Virdi et al. (2003). El Batran et al. (2006) reported that bitter gourd extracts showed anti-diabetic, hepato-renal protective and hypolipidemic effects in alloxan-induced diabetic rats. Wu and Ng (2007) found that extracts of wild bitter melon grown in Taiwan, possessed potent antioxidant and free radical-scavenging activities. Some researchers have also found that Thai bitter gourd fruit contained anticarcinogens or chemopreventive agent ([Kusamran et al., 1998] and [Yasui et al., 2005]). However, there has been little information regarding antioxidant activities of different parts of bitter gourd (mostly reported on fruit), especially leaf and stem, which are commonly consumed as vegetable in Thailand. Therefore, the purpose of this present study was to investigate phenolic compounds of bitter gourd fractions and to evaluate antioxidation activity by using different in vitro methods. Different fractions of Thai bitter gourd (M. charantia L.), namely leaf, stem and fruit fractions, were determined in an attempt to make systematic comparisons among their antioxidant activities and to identify the fractions with high antioxidant activity for further studies. In addition, correlations between total phenol content and antioxidant activity, assessed by different methods, were also evaluated. This research was conducted by Asst. Prof. Dr. Sirithon Siriamornpun and her Master’s degree student, Miss Jittawan Kubola. The research finding was published in Food Chemistry, Vol. 110 (2008), Page 881-890.