Studies on the mode of action of some molluscicides on the snail, Biomphalaria alexandrina. I. Effect of Bayluscide, sodium pentachlorophenate, and copper sulphate on succinate, glutamate, and reduced TMPD oxidation

The effects of extracts from Tetrapleura tetraptera (Taub.) and Bayluscide on cells and tissue structures of Biomphalaria glabrata (Say)

Subchronic experiments were conducted with low concentrations of saponins from Tetrapleura tetraptera and Bayluscide to study the ultrastructural effects of these molluscicides on Biomphalaria glabrata. The ratio of the digestive cells to the crypt cells was inverted in molluscicide treated snails which showed an increase in the number of secretory cells and a decrease in the number of digestive cells. In the snail foot connective tissues, dose-dependent autolytic areas were observed. The major ultrastructural effects were seen in the digestive gland with dose-dependent autolysis of the membranous structures such as the golgi apparatus, mitochondria and endoplasmic reticulum. The results show that the molluscicides produced non-specific effects on the membranous structures.

Synthetic and pharmacological studies on some transition metal chelates involving N-pyrimidino benzamide-2-carboxylic acid as ligand

N-pyrimidino benzamide-2-carboxylic acid (NPBCA) and its Cu(II), Ni(II), Co(II), Zn(II), and Mn(II) chelates have been synthesized and characterized by using elemental analyses, molar conductance, molecular weight determination, magnetic moment, infrared, and electronic spectra. Antifungal activity of the synthesized compounds has been screened on common fungi, viz., Aspergillus niger, Aspergillus nidulense, and Candida albicans at 28 degrees C and antibacterial activity has been observed on gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria at 37 degrees C. Anti-inflammatory and ulcerogenic potential of the synthesized compounds have been discussed.

Histochemical studies of some enzymes in the tissues of the schistosome vector snail Bulinus truncatus (Audouin) with special reference to the effects of a molluscicide. I. Dehydrogenases

The histochemistry of five dehydrogenases, namely isocitrate, succinate and lactate dehydrogenases and NADH and NADPH diaphorases were studied in the tissues of the schistosome vector snail, Bulinus truncatus, before and after treatment with the molluscicide Frescon. Isocitrate and succinate dehydrogenases showed their strongest activity in the respiratory epithelia, while lactate dehydrogenase showed a high level of activity in the tissues that are known to be capable of glycolysis. Following the administration of Frescon, a marked loss in the activity of isocitrate dehydrogenase and NADPH diaphorase occurred. It is postulated that the molluscicide toxin may interfere with cellular respiration, especially in the exposed areas of the body.