Cardanol from cashew nut shell liquid and its acetate ester : preparation and evaluation of toxicity against dog ticks (Rhipicephalus sanguineus)

Date

4-2007

Degree

Bachelor of Science in Chemistry

College

College of Arts and Sciences (CAS)

Adviser/Committee Chair

Hidelisa P. Hernandez

Abstract

The extraction of the cashew nut shell liquid was done by roasting the cashew nut shells wherein anacardic acid was decarboxylated and converted to cardanol. After the thermal treatment, a dark brown viscous liquid called technical CNSL was obtained with a yield of 18%. The absence of the anacardic acids in technical CNSL obtained was confirmed by TLC using CHCI3:EtOAc:HCOOH (95:5:2, v/v/v) solvent system and was further verified through IR analysis which showed absence of the C=0 bond stretch. The isolation of cardanol from the technical CNSL involved the use of 8:5 methanol: ammonium hydroxide (v/v) to separate the cardol and cardanol components of CNSL based on their relative acidity. The percentage yield of crude cardanol was 46%. The cardanol was characterized using TLC, IR and NMR analysis. The molecular weight of the compound was calculated to be 294.4 g/mol from the neutralization equivalent. The acetate ester was prepared by reacting the cardoxide with acetic anhydride. The percentage yield of the crude acetate derivative was 83%. TLC showed a new spot with a lower 14 value compared with that of cardanol and a light spot corresponding to cardanol was observed in the chromatogram. IR analysis showed the presence of the 0=C-O-C bond stretching of an ester. The presence of the unreacted cardanol was also confirmed by the broad OH stretching signal. The NMR spectrum indicated the presence of an acetate group which: confirmed the formation of cardanol acetate. The possible acaricidal activity of technical CNSL, crude cardanol and crude cardanol acetate against brown dog ticks, Rhipicephalus sanguineus was assessed by preparing 10000 ppm, 1000 ppm and 500 ppm methanolic solutions to determine the toxicity of each test materials. The percent mortality and the relationship between the different groups and the time interval were analyzed using ANOVA and DMRT. A 5000 ppm carbamate solution, distilled water and methanol were used as controls. The statistical results show that the 10000 ppm technical CNSL was the most toxic followed by the 10000 ppm cardanol after 15 minutes exposure. The 1000 ppm technical CNSL and cardanol also exceeded the activity of the positive control, 5000 ppm carbamate solution. The cardanol acetate showed a relatively lower toxicity towards the test specimen. The study indicates the technical CNSL and cardanol could be a potential ingredient and cheaper substitute in the formulation of tick control products.

Language

English

Location

UPLB Main Library Special Collections Section (USCS)

Call Number

LG 993.5 2007 C4 M37

Document Type

Thesis

This document is currently not available here.

Share

COinS