Preparation of High-quality Oil from Vegetable Oil with High-free Fatty Acid (FFA) Content Using an Ammonia/Methanol Solution.

There are significant concerns regarding the quality of vegetable oils in the food and biofuel industries. In this study, we explored the preparation of high- quality oil from high-free fatty acid (FFA) vegetable oil using an ammonia/MeOH solvent as an alkali base. Among the six tested solvents, MeOH was the most suitable for the separation of the oil and FFAs. Among the three alkali bases, ammonia enhanced the miscibility of FFAs in MeOH by forming ammonium salts. The amounts of FFAs in the upper layer and oil in the lower layer were positively correlated (r = 0.9348 and 0.9617, respectively) with MeOH. With increasing MeOH concentration, the amount of oil in the lower layer increased along with the FFAs in the upper layer. Using the molar ratio of ammonia to FFA 1:1 and the ratio (v/w) of MeOH to oil 4:3, 91.6% FFAs and 97.8% oil in the upper and lower layers, respectively, were produced from 50% FFA oil. Using a relational expression of FFAs and oil in the upper layer, 97.1% FFAs and 99.6% oil in each layer was obtained from 10% FFA oil. The oil in the lower layer was further purified by extraction with MeOH. This method is easy and efficient for the separation and purification of oil, accompanied by the reuse of reagents with almost no loss of raw materials.

Radiation degradation of (1→3)-ß-d-glucan from yeast with a potential application as a plant growth promoter.

The (1→3)-ß-d-glucan extracted from the yeast cell wall was irradiated by γ-rays from a Co-60 source at dose range of 100-300kGy in a swelling condition of 10, 15 and 20% for degradation. The water-soluble contents of irradiated samples obtained by 10% (1→3)-ß-d-glucan mixture increased from 25.89 to 66.71% by the increasing of irradiation doses from 100 to 300kGy. While the molecular weight of the water-soluble (1→3)-ß-d-glucan was found to be decreased from 48.13 to 10.77kDa. In the UV-spectra of irradiated water-soluble (1→3)-ß-d-glucan, a new peak appeared at 265nm with the intensity increased by the increase of the dose. The IR spectra of irradiated (1→3)-ß-d-glucan were recognized by a decrease of the peak intensity at 1156cm(-1) indicated to COC glycosidic linkages with the increasing of irradiation dose. In addition, radiation degraded (1→3)-ß-d-glucan with Mw about 18kDa prepared at the dose of 250kGy displayed a strongly promotion effect on the growth of mustard green and the optimum concentration of the degraded (1→3)-ß-d-glucan was found to be about 75mgl(-1). Thus, the degraded (1→3)-ß-d-glucan prepared by radiation technique displayed as a promising, safety and high effective plant growth promoter for agriculture application.

Preparation of oligoalginate plant growth promoter by γ irradiation of alginate solution containing hydrogen peroxide.

Degraded alginate compounds with molecular weights of 7-26, 40-77, or 11-26 kDa were obtained by γ irradiation, hydrogen peroxide (5% H(2)O(2)) treatment, or a combination treatment involving ionizing radiation and H(2)O(2), respectively. The 14 kDa oligoalginate, prepared by the combined method, promoted the growth of mustard greens and lettuce at an optimal concentration of 75 mg/L. The growth promotion effects of the oligoalginate prepared by γ irradiation in the presence of H(2)O(2) were statistically equivalent to those of the oligoalginate prepared by γ irradiation only. The combination of γ irradiation and H(2)O(2) reduced the required irradiation dosage by a factor of 9 relative to the oligoalginate produced by γ irradiation only. The combination treatment (γ irradiation/H(2)O(2)) may be carried out on a large scale at low cost to produce oligoalginate for use as a plant growth promoter in agricultural industries.