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Abstract Azotobacter Chroococcum, Azotobacter vinelandii and Escherichia coli. were subjected to genetic transformation in order to aquiresaponin for producing ability. The transforming materials in case of Azotobacter sp. were Saponaria high molecular weight DNA, Saponaria officinalis fresh roots DNA, Poinciana regia chromatin DNA and Asparagus officinalis fresh roots DNA, each of concentration 22 ug/ml, In case of E.coli, the transforming material was Saponaria fresh roots DNA of concentrations 66, 50 and 30 J.1g/ml. Some biolgocial activites of saponin in each ofliquid culture of transfonnant and untransfonnant Azotobcter, culture supernatant, cell suspensions and extracted (TLC) saponin bands of culture supernatants of isolate (1) of transfonnant, untransfonnant and isolate ”2” of transfonnat’ltE. coli were tested with comparison to aqueous extracts of 3 plants (Saponaria, Poinciana: and Asparagus) of different concentrations as follow: . I. Haemolytic activity: About 0.5 ml from each saponin solution mentioned above was added to 5 ml of blood corpuscles suspension, Kept at room temp. for 5 minutes, centrifuged at 3000 rpm for 15 minutes. The content ofH.b in supernatant was measured in coloremeter at 540 G.D. The saponin content of unknown samples were caleculated from the linear portion--_.of the standrd curve which was constructed for white saponin of Merck. n Moluscicidal activity: Ten snails (Biomphalaria alexandrina) were transferred to about 10 ml from each tested saponin solutionand dechlorinated H2O as control for 24 hrs in duplicate then transferred to dechlorinated water for 24 hr. After recovery, mortality was calculated. m. Nematicidal activity: About 1000 2-nd stage juveniles were transferred to 10 ml of each tested saponin soultion and distilled water as control in triplicates for 24 hrs then were transferred to aerated water for 24 hrs. Mortality percentages of nematodes were calculated after recovery. - Type of saponin in plants was determined by the colour produced by application of the liebennann- Burchard reaction. - Various transformation frequencies in case of Azotobacter were observed. The highest frequency was obtained from the two types of Saponaria DNA. - Transfonnant E.Coli were obtained with the concentration 66 ~glml and the transformation frequency was 0.00096. - Untransfonnant bacterial strain don’t produce saponin and don’t exhibit any of its examined biological activities. - Transfonnant strains exhibited various degrees of biological activites of saponin as follows:- - The Azotobacter chroococcum transformed by Saponaria high molecular wieght DNA gave the highest (60%) molluscicidal activity. This mortality value was equal to that obtained from standard saponin (Merck) cone, of 0.015mglml). While the highestmolluscicidal activity of cell suspensions of E.coli was that of the isolate (2) of transformed strain (30%, equivalent to 0.014 mglml of Merck saponin) which cause decrease in DNA content of snails to the lowest value (5.2 mglg of snail tissue) with comparison to control which have (23.1 mglg of snail tissue). - The purified saponin extracted from culture supernatant of transfonnant E.coli mortalized snails at the maximum percentage (100%), which was equivalent to the mortality caused by 0.0175 mglml of Merck saponin, the DNA content of dead snail tissue was reduced to about 4.1 mglg of snail tissue. Cell suspension and the spots dervied from the wild E.Coli showed no molluscicidal activity. - The best potent saponin examined in 3 plants was that of Saponaria and Asparagus (LCso were 35, 40 mglml) respectively for snails, which equivalent ot the mortality caused by 0.015 mglml of Merck saponm. Nematicidal activity: - A. chroococcum transformed by Saponaria high molecular weight DNA gave the highest nematodes mortality (50%) which corresponds to 80 mglml concentation of Merck saponin. -Cells suspension of isolate (1) oftransfonnant E.Coli gave the highest nematodes mortality percentage (60%) in comparison to the cell suspension of wild type and isolate (2) oftransfonnant E.Coli -Purified saponin extracted from culture supernatant of isolate (1) of transformant and isolate (2) of transformant E.coli. caused 100% nematodes mortality, equivalent to 160 mglml of Merck saponin. - The best potent saponin examined in 3 plants was that of Saponaria and Asparagus LCso for nematodes were 100 mg plant! ml from each plant. Haemolytic activity: Culture of A. chroococcum transformed by fresh Saponaria .DNA could hemolyze red blood cells to an extend equal to the obtained by 40.8 mgl ml of standard saponin. - Haemolytic activity of isolate(l) of transformant and isolate (2) of transformant E.coli cell suspensions was greater than that of the supernatants. Isolate (1) of transformed strain gave stronger hemolytic action than isolate (2) of transformed strain in both cases. - The hemolytic activity of purified saponin extracted from culture supernatant of isolate (1) oftransfonnant E.coli was lower than that of isolate (2) oftransfonnant one (0.5 and 0.736) respectively. - Aqueous extracts of Saponaria roots and Poinciana seeds at cone. of 100 mg plant! ml gave stronger hemolytic action than aqueous extract of the same cone, from Asparagus, this may be due to the differene in.raponin type (triterpenoid in Saponaria and Poinciana, but it its steroid in Asparagus). - Aqueous extract of Saponaria could hemolyze red blood cells to an extend equal to that obtained by 0.DI5 mglml of standard saponin, so Saponaria is considered to be the most producer for saponin than Asparagus and Poinciana. |