Plants and their distribution into families
The result of the present study showed that 50 species of plants were used by the Kavirajes of Chalna area in Khulna district, Bangladesh. These medicinal plants belonged to 49 genera and 33 families (). The Fabaceae family provided the largest number of species (6), followed by Acanthaceae, Euphorbiaceae, Lamiaceae, and Poaceae families (3 species each), and Amaranthaceae, Araceae, Asteraceae and Malvaceae families (2 species each). Other families were represented by one plant each. Out of the 50 plant species obtained in the present survey, several species were cultivated and used either for direct consumption or sold commercially. These species included Spondias dulcis, Alocasia macrorrhizos, Carica papaya, Brassica oleracea, Hibiscus esculentus, Psidium guajava, Piper chaba, Olea europaea, and Zea mays. Several other species were not systematically cultivated but grown around the homesteads or along rural roads for their medicinal values, shade giving effect, ornamentals or for feeding leaves to cattle. These plants included Ervatamia divaricata, Clitoria ternatea, Saraca indica, Ficus hispida, and Cedrus deodara.
Listing of medicinal plants obtained from the traditional medicinal practitioners of Chalna area, Khulna district, Bangladesh.
Plant parts used and mode of preparation
The various plant parts used included whole plants, leaves, stems, roots, barks, flowers, fruits, and seeds. In total, 71 uses of whole plants or plant parts were reported for the 50 species collected in the present survey. displays the results on medicinal plant parts used to treat human ailments. The Kavirajes used several different types of preparation for a particular plant or plant part. Most often, the whole plant or plant part (leaf, stem, root) was crushed thoroughly to extract juice and the juice administered orally after straining through a piece of cloth. A decoction was sometimes prepared, which typically involved boiling the plant or plant part (leaf, bark) in four volumes of water till the volume has been reduced by half. The decoction was then strained through a piece of cloth and administered orally. On other occasions, a plant or plant part was dried and made into pills and the pills administered orally. Seeds were in general not administered orally; for most purposes oil was extracted from the seed and that oil used for topical applications.
Parts of medicinal plants used to treat various ailments.
In general a single plant was used by the Kavirajes to treat multiple ailments, which can be as high as six in number. Plants that were used to treat four or more ailments included Barleria lupulina, Hygrophila auriculata, Sansevieria trifasciata, Amaranthus spinosus, Spondias dulcis, Centella asiatica, Gnaphalium luteo-album, Tridax procumbens, Carica papaya, Brassica oleracea, Trichosanthes kirilowii, Excoecaria agallocha, Cassia fistula, Cassia occidentalis, Saraca indica, Sesbania grandiflora, Anisomeles malabarica, Clerodendrum inerme, Cuphea hyssopifolia, Psidium guajava, Cedrus deodara, Hygroryza aristata, Phragmites australis, Zea mays, Persicaria hydropiper, Richardia scabra, Murraya paniculata, Veronica officinalis, and Boehmeria macrophylla.
Twenty five (25) plants were used to treat skin diseases and 23 plants for treatment of Gastro intestinal tract disorders, which included constipation, indigestion, stomachache, diarrhea, and dysentery. This suggested that skin and intestinal tract disorders were the common afflictions of the population in the area. 14 plants were used to treat respiratory tract disorders (cough, cold, mucus, bronchitis, asthma). It was interesting to note that 14 plants were also used by the Kavirajes to treat cancer or tumor, suggesting that the area might be a rich source of plants with anti-cancer activities. 9 plants were used as insecticide, 8 for rheumatoid arthritis, and 7 plants for healing wounds. 5 plants were used to treat jaundice. 5 plants were also utilized to treat animal and snake bites, which included tiger bites. The surveyed area is within the vicinity of the Sunderbans forest region and a number of people are engaged in collecting honey, fish and timber products from the forest, which makes them a target for tiger attacks. Six (6) plants were used to treat diabetes, and 2 each for the treatment of leprosy, and sexually transmitted diseases like gonorrhea. 5 plants were used to treat impotency, while 1 plant was used as an abortifacient. 3 plants were used to treat helminthiasis, which we found to be quite common amongst the population, while 4 plants were used to treat heart disorders. The medicinal plant species that were used by the Kavirajes included true mangrove species like Excoecaria agallocha and Ceriops tagal.