Antioxidant And Antibacterial Activity Of Biological Active Components From Zanthoxylum Bungeanum Maxim Seed

Zanthoxylum bungeanum seed is the main by-product of Zanthoxylum bungeanum Maxim and it is abundant in nutrients and biological active ingredients, so as to it is more and more widely researched. Among these existing researches, the development and application of protein resource and other active substances are gradually enriched and improved. In this study, degreased Zanthoxylum bungeanum seed was the raw material. Firstly, melanin, ethanol extraction and different polar parts and crude protein hydrolysate were extracted in different ways. Secondly, in vitro antioxidant and antibacterial ability were explored. Finally, crude protein hydrolysate was applied in chilled pork to investigate application value of these test extractions. Further more, this study lay certain theoretical basis for further utilization and promote the economic additional value Zanthoxylum bungeanum seed.1.The study evaluated the in vitro antioxidant activity of the melamin extracted from the Zanthoxylum bungeanum seed by measuring total reducing force and antioxidant activity, the rate of scavenging super oxide anion free radicals, hydroxyl free radicals, DPPH free radicals as well as inhibition of lipid peroxidation. The results showed that there were positive correlation between antioxidant activity and concentration of the melanin extraction solution. At the concentration of 1.0 mg/mL, the absorbance value of the total reducing force and antioxidant activity were 0.782±0.065 and 0.18±0.003 respectively and the inhibition rate of lipid peroxidation reached 65.68±1.13%, closed to Vc. The rate of scavenging DPPH and hydroxyl free radicals achieved 50% when the concentration of melanin were 0.66 and 0.76 mg/mL respectively. The four indicators above were weaker than Vc. But the rate of scavenging super oxide anion free radicals was far higher than Vc and when came to 0.1 mg/mL, the rate reached 65.43±0.70%. The research showed that the melamnin of Zanthoxylum bungeanum seed is one kind of natural pigment resource of good antioxidant activity.2. This study selected 95% ethanol as extraction solvent and soaking with ultrasonic-assistant as extraction means by comparing yield, impurity content of melanin, content of biological active component and antioxidant and antibacterial activity in different concentrations of ethanol and extraction methods(soaking, ultrasonic treatment, reflux treatment and heating) to extract the Zanthoxylum bungeanum seed. On this condition, the yild was 5.04±0.90% and total content of flavonoids and polyphenol were 9.69±0.003 and 208.22+8.08 mg/g respectively. The extraction solution absorbance was the lowest that indicated the least containing of melanin impurities. It had good total reducing power and good ability to scavenge DPPH and ABTS radicals which IC50 were 0.066 and 0.43 mg/mL respectively. The sizes of inhibition zone were 14±1.00mm(E.coli)? 13.5±0.50mm(S.aureus)?12.43±0.12mm (B.subtilis) and it had no antibacterial effect to Salmonella.sp.3. This study compared different polor parts(N-butanol, petroleum ether, chloroform ethyl acetate and water extracts) of Zanthoxylum bungeanum seed ethanol extracts in content of biological active component and antioxidant and antibacterial activity. And the results showed that medium polor parts(N-butanol and ethyl acetate extracts) had better antioxidant and antibacterial ability. The yield of N-butanol extracts was 11.19±0.01% and total content of flavonoids and polyphenol were 9.6±0.30?347.7±1.05 mg/g respectively, and It's total reducing power, scavenging ability of DPPH and ABTS radicals showed the best. The following was ethyl acetate extracts. The chloroform extracts had the best inhibition ability of lipid peroxidation among all the polar parts. And water extrats showed the best ability to scavenge super oxide anion free radicals. Ethyl acetate extracts and chloroform extracts had the obvious inhibitory effect. The orders of antibacterial effect of the two parts were S. aureus> B.subtilis> E.coli>S.sp and B.subtilis>E.coli> S.aureus>Salmonella.sp.4.The research used colony forming unit, sensory evaluation, pH, volatile basic nitrogen value (TVB-N), thiobarbituric acid value (TBA), drip loss and other indicators to evaluate preservation effect of the crude protein hydrolysate from zanthoxylum bungeanum seed to chilled pork. The results showed that the crude protein hydrolysate can inhibit the growth of microorganisms effectively, delayed the rise of TVB-N value and drip loss, decreased the oxidation rate of TBA. In all experimental groups, the 2.5% hydrolysate group had the best preservation effect compared with negative control. The study indicatied that the crude protein hydrolysate from zanthoxylum bungeanum seed was a new type natural antistaling agent of obvious effect, low cost and high application value.