Peteroselinum crispsum (Parsley) is a bright green, biennial herb, which belongs to the family Apiaceae. Native to the central Mediterranean region (Southern Italy, Algeria and Tunisia) and naturalised elsewhere in Europe, Africa and Asia. It is commonly used as a ganish in soups, salads, meats, vegetables and sauces . Traditionally, the leaf, seed and root are being used in herbal medicine as enema, orally as tea to control high blood pressure and tonic to strengthen the bladder [2, 3]. Other ayurvedic uses of the plant includes treatment of nose bleeding, hematoma, skin blemishes due to it’s bleaching properties, halitosis, ear ache, otitis, and as an emenagogue favouring menstruation and alleviating it’s pains. The myristicin and apiole contained in the plant have the properties to increase the production of oestrogen which make their use relevant in menopause. However, large amount can have uterotonic effect and therefore it’s use is contraindicated in pregnancy and ingestion of more than 10 drops a day of the oil may cause abortion. Parsley is also widely used as a galactofuge by lactating mothers to stop excessive milk production [4, 5].
Although, the use of the plant is discouraged in heart and kidney disorders due to its water retention capabilities, however, its anti inflammatory and probable immune boosting properties make it relevant in the traditional treatment of urinary tract infection, nephritis, cystitis and prevention of renal stones formation. In addition, it is also a common home remedy for obesity and reduction of itching in insect bites . Peteroselinum crispsum increases diuresis by inhibiting the Na+/K+ - ATPase pump in the kidney, thereby enhancing sodium and water excretion while increasing potassium resorption [6, 7].
With reference to herb-drug interactions, Parsley has been known to interfere with warfarin (Coumadin) treatment due to it’s high content of vitamin K . It’s use is also contraindicated in diuretic treatment with potential of causing excessive loss of water. In addition, patients on aspirin therapy should avoid ingesting Parsley due to possible increased sensitivity and allergic reactions [4, 8]. The presence of myristicine, a narcotic which affects the central nervous system can interfere with opoid therapy and when ingested in excess may cause convulsions and serotonin syndrome [9, 10].
It is pertinent to note that the ingestion of the plant is toxic to many domestic animals including horses, cats and dogs due to the action of furocoumarins causing symptoms such as photosentisization, ulcerative and exudative dermatitis and ocular toxicity that may require veterinary consultation .
Consideration should also be giving to sources of plant cultivation due to the fact that resorption of heavy metals by the plants has been observed in soil irrigated with untreated waste water making the plant a potential source of heavy metal toxicity .
Phytochemically, the leaves and seeds of P. crispum has been shown to contain high levels of essential oil known as apiole, while the tender buds contain psoralen and related compounds that can induce photosensitivity and these include xanthotoxin, ficusin, bergapten, majudin, heraclin and antimicrobial furocoumarins namely 8-methoxypsoralen, 5-methoxypsoralen, oxypuecedanin, isopimpinellin, 6’-acetylopin and a new monoterpene glycoside [13–15]. The seed also contains cafiolene, beta-phelandrene, myrcene, fat and myristicin. Furthermore, the plant is a good source of iron, calcium, phosphorous and antioxidants like luteolin, vitamin C, vitamin A and zinc and these may likely account for it’s hepato protective effect [16, 17]. However, in one study, combined treatment of rat with CCl4 and P. crispum extract demonstrated both synergistic and antagonistic effects on the liver .
While phytochemical and pharmacological experiments with P. crispum extract have been undertaken with disparity on its hepatotoxic effect, toxicity testing using biochemical and haematological data are not available. This present study evaluated the toxic effects of the extract of P.crispum on two target organs; liver and kidney, some plasma biochemical and haematological parameters.