Study On Enzymatic Refining Of Camellia Seed Oil And Its Effect On Hyperuricemia

Camellia seed oi is woody plant oil prepared from the mature seeds of Camellia oleifera Abel.It contains a variety of unsaturated fatty acids,squalene,phytosterols,polyphenols and other lipid concomitants,which have powerful antioxidant and anti-inflammatory activities.The quality of Camellia seed oil is closely related to the refining process and storage process of Camellia seed oil.As the first step of Camellia seed oil refining,degumming plays a decisive role in the subsequent refining steps,and also affects the quality of Camellia seed oil.This paper mainly studied the optimization of the PLA₁ enzymatic degumming process of Camellia seed oil,and compared the degumming effect and storage stability of Camellia seed oil treated under the optimum condition of the PLA₁ enzymatic degumming process with the traditional degumming method,in order to improve the refining efficiency and quality of Camellia seed oil.Finally,Camellia seed oil and its concomitants,squalene andβ-sitosterol,were used to intervene the diet of hyperuricemia mice,to explore the effects of Camellia seed oil intake on hyperuricemia,and to provide reference for its related application.The main research contents are as follows:（1）Using Camellia seed crude oil as raw material,single factor and response surface experiments were used to optimize the degumming process of Camellia seed oil PLA₁ enzymatic method,and the degumming effect was compared with that of hydration and acid method.The results showed that after the optimized PLA₁ deep degumming treatment,the residual phosphorus content was less than 10 mg/kg,which met the requirements of physical refining.The degumming effect of hydration degumming,acid degumming,PLA₁ simple degumming and PLA1 deep degumming had significant differences（P<0.05）,and the degumming rate of the PLA₁ deep degumming method was 96.61±0.81%,and the degumming effect was the best.The four degumming methods significantly decreased the polyphenol content（P<0.05）,but more than 87%of polyphenols remained in the oil,which did not significantly affect the acid value,peroxide value,squalene andβ-sitosterol contents（P>0.05）.The fatty acid composition of oil before and after the four degumming methods was the same,and the proportion changed slightly.（2）Schaal oven method was used to accelerate oxidation of Camellia seed crude oil,hydrated degumming oil,acid degumming oil,PLA₁ simple degumming oil and PLA₁ deep degumming oil for 30 days,and the storage stability of 5 Camellia seed oil was evaluated.The results show:The acid value,peroxide value,anisylamine value and total oxidation value of the five Camellia seed oil increased continuously with the extension of accelerated oxidation time.Among them,the index of PLA₁deeply degum Camellia seed oil had the slowest rising value and the lowest rising value.The acid value was 1.68±0.002 mg/g and the peroxide value was 52.11±4.01mmol/kg at the 30th day.The anisidine value was 16.11±0.19（no unit）,and the total oxidation value was 224.66±16.07（no unit）.The contents of polyphenols,squalene andβ-sitosterol of the five Camellia seed oil decreased gradually with the extension of accelerated oxidation time,among which the consumption rate of three active substances in PLA₁ deep degummable Camellia seed oil was the lowest,and the residual amount was the highest.The residual polyphenols at the 30d were11.35±0.10 mg/kg.The residues of squalene were 157.58±0.41 mg/kg andβ-sitosterol was 173.61±7.54 mg/kg.Correlation analysis showed that there was a negative correlation between the physicochemical index data of 5 kinds of oil and the content of bioactive substances,and the change of bioactive substances content in oil would lead to the change of physicochemical index,thus affecting the storage stability.With the accelerated oxidation,SFA and MUFA of the five Camellia seed oil increased gradually,while PUFA decreased gradually.The change rate of n-6 PUFA was lower than that of n-3 PUFA,and the change rate of PUFA degummed by PLA₁ enzyme was lower.During the accelerated oxidation period,all 5 kinds of camellia oil gradually oxidized rackness,among which 2 kinds of oil degummed by PAL₁ enzymatic method had lower rackness rate and better storage stability.（3）A mouse model of hyperuricemia was established,and intervention was carried out with hydration degummed Camellia seed oil,PLA₁ deep degummed Camellia seed oil,refined Camellia seed oil,squalene andβ-sitosterol.The results showed that the body weight of mice in other groups increased gradually with the extension of time except for allopurinol intervention group.Intake of Camellia seed oil,squalene andβ-sitosterol had positive effects on reducing serum uric acid,serum creatinine and serum urea nitrogen levels and liver XOD activity in hyperuricemic mice,but did not cause abnormal lipid metabolism level in mice.After ingestion of Camellia seed oil,squalene andβ-sitosterol,SOD and CAT enzyme activities in liver of hyperuricemia mice were restored,and MDA production was reduced,which significantly inhibited or alleviated liver oxidative damage.