PHYSICOCHEMICAL CHARACTERISTICS, PHYTO-CHEMICAL COMPOSITION AND ANTI-MICROBIAL PROPERTY OF MILK-BUSH SEED. (Thevetia peruviana)

Abstract

The raw and boiled seeds of thevetia peruviana were analysed for proximate composition, mineral content, amino acid contents, fatty acids, while the oil extracted from the seeds were evaluated for physicochemical properties such as: specific gravity, iodine value, refractive index, peroxide value, saponification value, unsaponification value and acid value using standard methods. Results for proximate (%) analysis for raw showed moisture content 2.0±0.00, ash content 3.33±0.58, crude protein 30.10±0.00, crude fibre 4.79±0.01, fat content 58.30±0.00 and carbohydrate 1.80±0.00 while that of boiled sample showed moisture content 2.89±0.19, ash content 2.96±0.01, crude protein 29.60±0.00, crude fibre 5.21±0.46, fat content 59.20±0.00 and carbohydrate 0.30±0.00. Mineral analysis (mg/l) for raw sample showed Fe(0.63), Cu(0.06), Mn(0.17), Na(3.50), K(22.80),Ca(0.32), Mg(2.00) and P(11,088.09) that of boiled sample showed Fe(0.60), Mn(0.15), Na(3.10), K(17.6),Ca(0.29), Mg(2.70) and P(12,657.06) while Cd, Pd, Cr for both samples and Cu for boiled were not detected. Results for physicochemical properties on the oil for raw sample are refractive index(1.463), relative density(0.89), viscosity(28.21), acid value(1.71), free fatty acid(0.86), saponification value(244.26), iodine value(84.60), peroxide value(3.85), unsaponification value(2.04), specific gravity(0.91) while that of boiled sample refractive index(1.465), relative density(0.88), viscosity(30.59), acid value(1.40), free fatty acid(0.71), saponification value(193.76), iodine value(77.83), peroxide value(11.51), unsaponification value(1.59), specific gravity (0.93). Fatty acid composition (%) for raw is given below myristic acid(0.14), palmitic acid(15.22), palmitoleic acid(0.50), stearic acid(5.38), oleic acid(54.75), linoleic acid(21.48), linolenic acid(0.61), arachidic acid(0.27), behenic acid(0.24), erucic acid(0.66) while that of boiled is myristic acid(0.19), palmitic acid(19.06), palmitoleic acid(0.25), stearic acid(7.08), oleic acid(52.45), linoleic acid(18.95), linolenic acid(0.38), atachidic acid(0.51), behenic acid(0.32), erucic acid(0.23). Results for amino acid composition (%) for raw sample are glycine(6.13), alanine(5.86), serine(5.46), proline(4.05), valine(4.56), threonine(5.11), isoleucine(4.42), leucine(6.64), aspartate(8.59), lysine(3.19), methionine(8.46), glutamate(18.42), phenylalanine(6.19), histidine(2.63), arginine(7.24), tyrosine(3.24), cystine(1.18) while that of boiled sample glycine(6.39), alanine(6.04), serine(5.61), proline(3.73), valine(4.48), threonine(4.60), isoleucine(4.07), leucine(7.39), aspartate(8.42), lysine(3.87), methoinine(5.27), glutamate(19.99), phenylalanine(6.05), histidine(1.25), arginine(6.38), tyrosine(3.00), cystine(5.89). The oil from the samples were tested against some organisms such as: Escherichia coil, Psuedomonas syringine, Pseudomonas aeruginosa, Bacillus subtilis, Bacillus cereus, Xanthomonas oximopoides and Condida albican. The n-hexane extract exhibited activity against all the organisms tested with zones of inhibition 9-14mm and 0.2-3mm respectively except Escherichia coil, and Pseudomonas syringine. The n-hexane extract showed high activity against Bacillus subtilis and Pseudomonas aeruginosa. The Phytochemical screening on the oil revealed the presence of flavonoids, saponins, steroids, cardiac glycosides, terpenoids, and alkaloids. The study shows that the oil from the seed of thevetia Peruviana contains compounds that have anti-microbial activity. In conclusion, the results show that boiling has little reduction on the characteristics of boiled thevetia peruviana seed and the oil is also suitable and useful for industrial applications.