BIOPHARMACOLOGICAL EFFECTS OF EXTRACTS OF SOME COMMONLY AVAILABLE INDIAN PLANTS ON CHANNA STRIATA

Six commonly available Indian plants extracts on Channa striata indicate that acetylcholine synthesis and acetylcholinesterase inhibition were observed in the heart, brain, muscle and liver tissues. The possibility of using the toxic substances as fish bait is discussed.


INTRODUCTION
Many Indian plants have been increasingly tested for a wide variety of biological activities including antifertility, anticancer, chemotherapeutic and pharmacological activities (Agarwal andRangari. 2003: Bol Kent et al., 2004).However, most of these studies were done only on mammals.
Though various plant extract are used as arrow poisons and fish baits,no study to date has evaluated the biopharmocological properties of these plant extracts on fresh water food fishes. In order to identify a substance which can be easily obtained and readily used for fish hatching purposes.We have evaluated to pharmacological effects of six commonly available poisonous plants in our area.

Collection of Plants
The following plants are collected and tested. Parts ethanolic extracts for 30 days.The level of plant extract was kept constant by changing the water everyday and adding the requistic amount of plant extract stock solution.They were fed daily prior to change of water to prevent ingestion of plant extract through food. A control group exposed to ethanol alone was also maintained. At the end of 30 day period, the fish were killed by decapitation and the tissues rapidly excised. The tissues were raised,blotted and homogenized in a motor driven all glass homogenizer with two volumes of chilled saline (0.7% Nacl). Homogenates were centrifuged at 10,000 g for 15 min.The supernatant fraction were diluted with ten volumes of chilled saline and used as the enzyme source.

Determination of Biopharmacological activity
The activities of acetylcholinesterase were determined according to the methods of Bock endahl and Ammon (1955) using 4.5 x 10-2 M acetylcholine as substrate.The acetylcholine content was determined after Metcalf (1951) (Hodges and Lehman, 1970).

Inhibition of Biopharmacological activity Parthenium hysterophorus
Compositae Leaves The results are presented in the Table 1 and  Table 2. From the results it is clear that acetylcholine

Procurement of fingerlings
These plants were screened for pharmacological effects in the commonly available and economically important freshwater food fish Channa Striata. The fishes (10-25g) were procured from local freshwater sources and held in laboratory in large plastic tanks (02: 6-7 mg/I; pH 6.7-6.9; fish density 8-15 g/I water) for 15 days before using in the experiments.Fishes were subjected to 50% in accumulated significantly and acetylcholinesterase is inhibited in the heart, brain, muscle and liver tissues of C.striata. Maximum inhibition is recorded for Parthenium and Datura. The accumulation of acetylcholine indicate the blockage of nerve impulse transmission. The rapid depletion of acetylcholinesterase again show the disruption of neuromuscular transmission.

Types of toxins in plants
All the six plants extracts contain potent toxic substances and inhibit the functioning of the nervous system.According to Viswanathan and Joshi (1983), some of the toxic substances present in the tested plants are Datura -tropane alkaloidsatropine,hyoscyamine and scopolamine Gloriosa -Colchicine(alkaloid) Vinca -75 alkaloids (Taylor and Fransworth, 1975) Calotropis -Steroidal glycoside-Calotropin Antiaris -glycoside α -antiarin Parthenium -sequiterpene lactone parthenin Plant derived substances are mainly evaluated for anti-inflammatory and antifertility activities in mammals (Agarwal and Rangari, 2003;Gupta and Sharma,2003). However,recently a potent cardiotoxic factor was isolated from the skin of C.Striata (Karmakar et al., 2002). These bioactive compounds inhibit respiratory enzymes (Al-Hassan et al., 1985). The nanotoxic effect and isolation of these compounds to use as fish bait is hither to unnoticed in many plants.Pond, river and lake fishing require cheap and safe fish baits.Synthetic pesticides and insecticides not only poison the fishes baited but also pollute the aquatic environment. Bioactive compounds are safe and environmental pollution is almost nil (Bol Kent et al., 2004). All the six plants tested are available throughout India and in many areas they are considered to be dangerous weeds for agriculture and livestock grazing.

CONCLUSION
The toxic substances present in the six plants inhibit the neuromuscular transmission.These toxic substances accumulate in the fish metabolism and cause neural problems to the people those who consume it. Therefore, proper arrangements have to be taken by the government and volunteers to eradicate the unwanted weeds from the crops and agriculture field. Value expressed as mean ± SD of 6 observations are significant p<0.001