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bioRxiv · 10.1101/2022.12.07.515639

Composition efficacy of Unsaturated Arachidonic acid, Diterpenoids, Malvin (C29H35ClO17), and Bergenin to neutralise venom from different venomous snake species.

Abstract

Snakebite envenomation is a serious problem in tropical and subtropical countries. Antivenom is the only treatment used to treat snake envenomation, however it is unable to neutralise local haemorrhage. Therefore, this studys aim is to evaluate the efficacy of P. dulce leaf extract to neutralise local haemorrhage induced by three clinically important snake species, B. jararaca, C. atrox and E. carinatus. Moreover, to determine the active components which are responsible for this activity. The plant leaves were extracted using different solvents, however, only E/e extract showed the best neutralizing capacity. The increasing doses, DF-1:2; 1:4, of E/e extract allowed better neutralizing ability s.c. In contrast, the oral/ i.p. acute toxicity test revealed that the optimal doses for the administration of E/e were 1 and 8 mg/kg. In addition to that, E/e was tested for its anti-lathality of LD50 using B. jararaca venom (1.1mg/kg) i.p., where the higher doses of 16 and 24 mg/kg killed 75% of BALB/C mice. Consequently, the different components of E/e extract were isolated with HPLC. The different components were grouped and tested to uncover the active ones. The results revealed that only three fractions were active, Frc11, Frc13, and Frc14. The active fractions showed a disparity in neutralizing the individual venoms, however, the best neutralising capacity was scored for Frc11. When the same fractions were pooled together, they showed a complete neutralizing ability against individual venoms as well as the pooled venoms. That was confirmed with the anti-gelatinase activity test, where pooled fraction inhibited the SVMP enzyme which is responsible for gelatinase activity. The phytochemical characterisation showed that the active fractions consist mainly of secondary metabolites such as tannins and polyphenols. MALDI-TOF MS confirmed the presence of secondary metabolites in the active fractions. The same fractions were tested for their anti-lethal activity using the pooled venoms (LD100), the results were statistically not significant, as all mice died including the positive controls. Nevertheless, the active fractions showed a noticeable increasing in survival time period especially Frc13 with an average survival time of 37 minutes. The positive control, IAV, scored the longest survival period with a gap of 11 minutes from Frc13.

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BibTeXRIS

Hasson, S. S., Altobi, L. N., Al-Jabri, A., Idris, M., Albusaidi, J. Z. K.. 2022-12-11. Composition efficacy of Unsaturated Arachidonic acid, Diterpenoids, Malvin (C29H35ClO17), and Bergenin to neutralise venom from different venomous snake species.. https://doi.org/10.1101/2022.12.07.515639

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