Preparation Of Three Inclusion Complexes And Study On Some Antibacterial Effects

After the previous study about volatile oil in antimicrobial activity, Cinnamaldehyde, citral and terpinene-4-ol were as the main research objects. The three volatile components are included by ?-cyclodextrin. Through qualitative and quantitative research on three kinds of inclusion complexes, we established the target substance content determination methods of three inclusion complexes, and the optimum preparation process was selected. At the same time, the antimicrobial properties of three kinds of volatile components were studied. Through preparing three substances of ?-cyclodextrin complexes, the main purpose of the study was to slow down the rate of volatilization, so as to provide references for the research and development of the three substances. The main results are as follows:1 ? By Fourier Transform infrared spectroscopy( FTIR) and Thin Layer Chromatography(TLC) methods, we studied the characterization of ?-cyclodextrin inclusion complexes of Cinnamaldehyde, citral, terpinene-4-ol. By FTIR method, we found that the group vibration of the three substances were masked or disappeared. This proves that ?-cyclodextrin embeded vibration peaks. Through TLC method, it can be known that the inclusion complexes contained three substances, and the inclusion complex can not detect the corresponding component in the thin layer plate. This indicated that Cinnamaldehyde, Citral, Terpinene-4-ol surely can be included by ?-cyclodextrin.2?To study the extraction methods of three substances ?-cyclodextrin inclusion complexes, we determined the optimal sample treatment methods. The sample treatment method of Cinnamaldehyde inclusion complex was ultrasonic extraction 30 min using 50% ethanol. The sample treatment method of Citral inclusion complex was ultrasonic extraction 15 min using methanol. The sample treatment method of terpinene-4-ol inclusion complex was ultrasonic extraction 60 min using methanol. Accordingly, we established methods for determination of the content of Cinnamaldehyde, citral, terpinene-4-ol in its inclusion complexes. The detection wavelength of Cinnamaldehyde inclusion complex was 291 nm, mobile phase of acetonitrile-water(60:40), the column temperature was 30?, the flow rate of 1 mL/min, injection volume of 10 ?L; The detection wavelength of citral inclusion complex was 243 nm, mobile phase was methanol-water(70:30), the column temperature was 30 ?, the flow rate of 1 m L/min, injection volume of 10 ?L; The detection wavelength of terpinene-4-ol inclusion complex was 210 nm, mobile phase of acetonitrile-water(83:17), the column temperature was 30 ?, the flow rate of 1 mL/min, injection volume of 10 ?L. By specific experiment, liner relation examination, precision test, repeatability test, stability test and sample recovery test, the methods proved to be feasible and effective.3?By saturated water solution method, water grinding method and method for dry grinding method,we prepared cinnamaldehyde, citral and terpinene-4-ol inclusion complexes, to screenning the optimal preparation method. The preparation factors, feed ratio, inclusion time and inclusion temperature, were to be optimized through single factor and orthogonal experiment. Cinnamaldehyde inclusion process is water grinding method; the molar ratio of Cinnamaldehyde and ?-cyclodextrin was 1.25: 1, and inclusion temperature was 30 °C, inclusion time was 45 min. As the result, the average content was 95.68 mg/g, and yield was 88.04%. Citral inclusion process is a saturated aqueous solution method, the molar ratio of citral and ?-cyclodextrin was 1: 1, inclusion temperature was 50 °C, inclusion time was 1.5 h. As the result, the average content was 112.70 mg/g, and yield was 93.01%. Terpinene-4-ol as the inclusion process of aqueous solution saturated with molar ratio of 1: 1. Inclusion temperature was 50 °C, and inclusion time was 1.5 h. As the result, the average content was 110.34 mg/g, and yield was 95.76%. Through the study of the stability of the three kinds of inclusion complexes, it increased the stability of volatile oils after inclusion. The remaining Cinnamaldehyde content of volatile oil was 52.89% after 15 days, while the content of inclusion complex was 82.29%. The remaining citral content of volatile oil was 31.47%, while the content of inclusion complex was 80.73%. The remaining terpinene-4-ol content of volatile oil was of 61.22%, while the content of inclusion complex after 15 days is still 91.21%. That indicated that inclusion complexes can improve stability, reduce volatilization.4?The preliminary research of three inclusion complexes against some plant pathogenic fungi were studied. The antimicrobial effect of cinnamaldehyde inclusion complex for Fusarium decemcellulare, Botrytis cinerea and Colletotrichum glycines while the cinnamaldehyde content was 0.4 mg/m L were obvious, and for Alternaria alternata, Alternaria solani which are resistance bacterial strain of carbendazim were also inhibited well. The effect of Citral inclusion for Botrytis cinerea, Alternaria alternate while the Citral content was 0.4 mg/mL were also obvious; however, the effect of citral inclusion for Colletotrichum glycines and Alternaria solani were not obvious. According to the stability of inclusion complex, it can be known that after inclusion the stability of cinnamaldehyde and Citral were increased and the rate of volatilization were reduced. So the inclusion complexes have long-lasting antimicrobial effect.Conclusion: By Fourier Transform infrared spectroscopy(FTIR)and Thin Layer Chromatography(TLC) methods, the three inclusion complexes were successfully detected; The antimicrobial study results of inclusion comlexes showed that, the antimicrobal effects of cinnamaldehyde inclusion complex for Fusarium decemcellulare, Botrytis cinerea, Colletotrichum glycines, Altternaria altternata and Alternaria solani was obvious. Citral inclusion complexes can inhibite part of the plant pathogens.