Bacopa monniera and Centella asiatica
In India, Bacopa monniera, known as "Brahmi", is revered in the indigenous system of medicine as a nerve tonic. In early literature, the name Brahmi was also used to refer to another plant species. Centella asiatica Linn., known as Indian penniwort. However, these plants are distinctly different. The name Jala-brahmi or water-brahmi assigned to Bacopa monniera in ancient Sanskrit writings provides the differentiation. The vernacular name "mandukaparni", often confused with Brahmi, in fact refers to Centella asiatica.
A critical study of the comparative phytochemistry, pharmacology and therapeutic properties of these two botanicals also support the view that they are distinct:
The Charaka Samhita considers them both to be promoters of cognitive functions, but it suggests that Brahmi is superior to mandukaparni. Brahmi is used to treat specific mental disorders such as insanity and epilepsy, while mandukaparni is a general rejuvenative tonic which improves mental health.
Brahmi promotes fertility and sustains implantation of the embryo in the uterus, while mandukaparni tends to reject the embryo. This suggests that the plant materials have opposite effects on uterine functions.
The Sushruta Samhita defines the properties of the herbs. Brahmi belongs to tikta rasa (bitter), while mandukaparni belongs to kasaya rasa (astringent).
Centella asiatica is a small herbaceous annual plant of the family Apiaceae, native to Asia. Also known as Gotu kola it has been used as a medicinal herb for thousands of years in India, China and Indonesia. Its ability to heal wounds, improve mental clarity, and treat skin conditions such as leprosy and psoriasis were important reasons for its extensive use.
As per Ayurveda Gotu kola herb is one of the chief herbs for revitalizing the nerves and brain cells; hence primarily known as a brain food in India. Its has been used for the purposes like boosting memory, wound healing, a mild diuretic, increasing concentration, alertness, as well as anti-anxiety and anti-stress. It has also been used for centuries in the treatment of liver and kidney problems.
Mandukaparni is one of the herbs mentioned in all ancient scriptures of ayurveda. It is often confused with brahmi (Bacopa monnieri), as Mandukaparni has synonyms like brahmi, brahma manduki, manduki, ekaparni etc. Infact mandukaparni and brahmi are entirely different plants, though have similar properties. Maharishi Charaka has categorized Mandukaparni as medhya (intellect promoting) or nervine tonic and as vayahstha pana (promotes longevity) and preserves youth. Bhavaprakasa has mentioned it as divya mahousadhi-the divine great drug. Sushruta has cited it as an alleviator of pitta dosha. Charaka has praised it to be an effective remedy for tuberculosis with deviation.
The plant grows in moist places throughout India; it is commonly seen in marshy banks of rivers, streams and ponds and irrigated lawns, fields etc. It is also found in Sri Lanka and Madagascar. The leaves are long-petioled, 1.5-6.5 cm in diameter, more rounded, with toothed margins. The Sanskrit name Mandukaparni refers to the leaves of the plant which resemble the claw of a frog. The flowers, minute, pinkish red, 3-6 in cluster. The fruit 8 mm long, like a grain of barley. The fruit 8 mm long, like a grain of barley. 7-9 ridged.
The botanical name of Mandukaparni is Centella asiatica and it belongs to family Umbelliferae, apiaceae. The glucosides, brahmoside and brahminoside have been isolated with their gennin brahmic acid. The Madagascar variety contains different glycoside known as asiaticoside, which is not found in Sri Lankan variety. But, arelated compound, centelloside and triterpenic acids, centoic and along with centellic acids have been reported (Indian J. Chem. Soc. 1956, 33, 893). The sapogenins and flavonoid components were same in both varieties. A new triterpene acid madasiatic acid – isolated and characterized. Also polyacetylenes (I, II, III, IV and V) and nine other acetylenes isolated. Also, madecassoside and asiaticoside isolated.
In pharmacological and clinical trials Centella asiatica has been found to improve the power of concentration and general ability and behavior of mentally retarded children. The clinical trials demonstrated that the extract increases the intelligence quotient in mentally retarded children. In a clinical trial an Ayurvedic drug having Centella asiatica as one of the main ingredients reported marked improvement is seen in children with behavioral problems. It is found to improve short-term memory and learning performance due to its possible nootropic action involving cholinergic and GABAergic modulation.