Strychnos nux-vomica L. (Loganiaceae)

Abstract

It is a tall deciduous tree, native to India, Sri Lanka, Myanmar, Thailand, and southern Vietnam. As medicine, seeds are considered by Unani physicians as nervine and cardiac tonic, stomachic, expectorant, aphrodisiac, blood purifier, anti-inflammatory, urinary bladder tonic and laxative. They are mainly used for phlegmatic nervous diseases, such as paralysis, facial palsy, arthritis, dyspnea, pleurisy and tuberculosis. The bark is also used as tonic and antipyretic. In small doses, it stimulates stomach and intestines, increases gastric, pancreatic, intestinal and biliary secretions. Therapeutic uses include paralytic and neuralgic afflictions, atonic diarrhea, chronic dysentery, prolapse of rectum, incontinence of urine, nocturnal emissions, debility or inactivity of spinal nerve system. Other uses include intermittent fevers, epilepsy, diabetes, anemia, and chlorosis. In Ayurveda, seeds are extensively advocated for nervous debility, paralysis, and weakness of limbs, sexual weakness, dyspepsia, and dysentery and in rheumatism. Dried seeds extract has been used as a circulatory and respiratory stimulant but effective doses are nearly equivalent to toxic doses. In Chinese traditional medicine, it is known as Maqianzi, which are seeds of three Strychnos species (Strychnos nux-vomica, S. pierrana, S. wallichiana), with bitter taste and cold property and is highly toxic. It is considered as channel-deobstruent, antirheumatic, detumescent, analgesic, and fortifies muscles, tendons and bones, and is indicated in rheumatism, paralysis or flaccidity of limbs or body, sequelae of poliomyelitis, rheumatoid arthritis, injuries due to falls, fractures, contusions, strains, and in schizophrenia. Seeds contain alkaloids (major poisonous alkaloids being strychnine and brucine); other constituents include minor alkaloids, glycoside, chlorogenic acid mannosan, and galactan, strynuxlines A and B, and iridoid glucosides. S. nux vomica seeds must be purified before their use in Unani and Ayurvedic medicines, and TCM. The purpose of purification process is to reduce its toxicity by reducing contents of strychnine and brucine. Low doses of seed ethanol extract effectively neutralized Daboia russelii venom-induced lethality, hemorrhage, defibrinogenating and PLA2 enzyme activities and Naja kaouthia venom-induced lethality, cardiotoxicity, neurotoxicity, and PLA2 enzyme activity in animals. Aqueous and 50% ethanol seed extracts also demonstrated significant antidiabetic activity in diabetic rats.