Secondary Metabolites of Medicinal Plants. Bharat Singh

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2.23 Catharanthus Species

      2.23.1 Ethnopharmacological Properties and Phytochemistry

      Catharanthus roseus (L.) G. Don. (Fam. – Apocynaceae), an important medicinal plant, contains alkaloids, used in the treatment of diabetes, blood pressure, asthma, constipation, cancer, and menstrual problems (Sain and Sharma 2013). This plant species is used in traditional medicine in several countries (Don 1999) such as South Africa, China, India, Mexico (Patel et al. 2012), and Malaysia (Ong et al. 2011), as a remedy for diabetic patients (Li et al. 2004). Alkaloids of C. roseus possessed hypotensive, sedative, tranquilizing, and anticancer properties. According to available literature on traditional system of medicine, the whole plant is used for relief from muscle pain and treatment of depression and wasp stings. It is also recommended for the treatment of nose bleeding, bleeding of gums, ulcers of the mouth, and sore throats (Kirtikar and Basu 1975), as well as hypertension, cystitis, gastritis, enteritis, and diarrhea and recovery of memory (Siddiqui et al. 2010; Mallik et al. 2013). Several vinca alkaloids including vinblastine, vincristine, vinorelbine, and vinflunine were isolated from Vinca rosea, and these isolated alkaloids have demonstrated antitumor activity (Schutz et al. 2011; Almagro et al. 2015).

      By using an aqueous acidic medium, 3′,4′-anhydrovinblastine and catharoseumine were isolated from freshly picked leaves of C. roseus (Goodbody et al. 1988). The isolated catharoseumine has cytotoxicity against HL-60 cell line (Wang et al. 2012). Similarly from the aerial parts of C. roseus, vindoline, vindolidine, vindolicine, roseadine, leurosine-N′b-oxide, leurocolombine, catharanthamine, pleuroside, dimethylvinblastin, 5′-oxoleurosine, leurosidine N′b-oxide, vinorelbine, vinzolidine, vineamine, raubasin, 16-epi-19-S-vindolinine, and vindolinine were isolated, and their identities confirmed by the analysis of spectral data (Sinha and Jain 1994; Atta-ur et al. 1983; Tiong et al. 2013; Aruna et al. 2015).

      The secondary metabolites are primarily used by medical sciences to control various diseases and ailments. The vincristine, vinblastine, and vindiscline have been identified from C. roseus. The isolated compounds possess antimetastatic activity by inhibiting microtubule formation (Negi 2011).

Vindogentianine, vindoline, vindolidine, vindolicine, vindolinine, perivine, coronaridine, voacangine, epi-ibogamine, ibogamine, 6-methyoxy-N-methyldihydroindole, desacetyl-N-methyl aspidospermine, ind-N-methylnorhanmine, velbanamine, cleavamine, vingramine, methylvingramine, leurosine, lochnerine, tricin, and serpentine were isolated from leaf extract of C. roseus (Jossang et al. 1998). Their structures were determined by analysis of physical and spectral data. Vindogentianine exhibited potential hypoglycemic activity in β-TC₆ and C₂C₁₂ cells by stimulating higher glucose uptake and significant in vitro PTP-1B inhibition (Johnson et al. 1963; Jossang et al. 1998; Tiong et al. 2015; Renjini et al. 2017). Vindoline, vindolidine, vindolicine, and vindolinine were isolated and identified from the dichloromethane leaves extract (DE) of leaves of this plant species. Vindolicine showed the highest antioxidant potential in several models such as oxygen radical absorbance capacity (ORAC) and DPPH as well as H₂O₂-induced oxidative damage in β-TC6 cells (Tiong et al. 2013; Vuong 2017). The high performance liquid chromatography (HPLC) determination of flowers and leaves of C. roseus showed the presence of rutin, quercetin, and gallic acid (Nisar et al. 2017). Phenolic acids such as p-hydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, vanillic acid, and gallic acid were also isolated from C. roseus (Mustafa and Verpoorte 2007), as well as α-amyrin, β-amyrin, and lupeol to ursolic acid, oleanolic acid, and betulinic acid (Huang et al. 2012).

2.23.2