| Thlaspi arvense L.is a traditional medicinal plant in China and widely distributes throughout China.However,T.arvense L.is often regarded as a field weed and its application value is ignored,which leads to waste of resources and potential economic losses.This thesis systematically studied the key technologies of the separation and application process of target components in the main utilization parts of T.arvense,including seeds,leaves and rhizomes,which established a process route for comprehensive utilization of T.arvense resources based on the concept of green chemistry.This would conduce to realize the high efficiency of multi-level utilization of T.arvense resources and meet social needs.The main research results are as follows:Microwave-assisted biphasic method(MABE)was established for simultaneously extracting oil and sinigrin from T.arvense seeds.The innovative process replaced the previous method that needed different polar target components were extracted batch by batch,namely,the fat-soluble seed oil and the strongly water-soluble sinigrin could be extracted at the same time.The single factor and response surface of BBD optimization experiments were used to the optimum conditions,the yields of oil and sinigrin were 23.46%±0.78%and 18.42±0.35 mg/g,respectively.Compared with the conventional method,the MABE method had a higher extraction efficiency,and the obtained T.arvense seed oil had a better quality.GC-MS analysis results showed that erucic acid accounted for the highest proportion of fatty acid composition of T.arvense seed oil(38.12%),which indicated that T,arvense seed oil was not suitable for edible oil,but it had better applications in the preparation of new industrial energy in the future prospect.T.arvense seed oil was used to prepare biodiesel under the action of a new Fe3O4@GO@PBIL core-shell magnetic catalyst.In order to make the preparation process of biodiesel from seed oil more green and environmentally friendly,Fe3O4@GO@PBIL core-shell magnetic catalyst was firstly prepared,and the synthesis catalyst was comprehensively characterized.The characterization results showed that Fe3O4@GO@PBIL core-shell magnetic catalyst had been successfully synthesized.The process of Fe3O4@GO@PBIL core-shell magnetic catalyst used in the preparation of biodiesel was optimized,the yield of biodiesel was 92.38%.The catalyst still presented high catalytic performance after being recycled for many times,which showed that it had good application prospects in the field of new energy preparation.The physical and chemical index measurement results of biodiesel met the standards of ASTM D6751 and EN 14214.T.arvense seed oil was a suitable feedstock for the preparation of biodiesel.The use of this method not only improved the value of T.arvense,but also contributed to the green-friendly development of the environment.The method of Microwave-assisted in-situ extraction of vegetable oil was used to separate essential oil from T.arvense leaves and seeds.In the innovative process,various vegetable oils were used as extractants to replace the use of volatile petroleum-based solvents such as dichloromethane,petroleum ether,and ether in the extraction process of plant essential oils.Firstly,the types of vegetable oils were selected,and coconut oil was selected as the essential oil extractant.The preparation conditions for extracting T.arvense essential oil was optimized,the yield of essential oil form T.arvense leaves and seeds were 0.72±0.02 mg/g and 2.56 ±0.08 mg/g,respectively.The results of GC-MS measurement showed that the allyl isothiocyanate(AITC)in the essential oil of T.arvense leaves and seeds was respectively 9.66%and 44.69%.AITC had various biological activities such as insecticide and bacteriostasis.The high proportion of AITC components made T.arvense essential oil had a variety of applications.Microwave-assisted acidic amino acid ionic liquid was used to extract isoorientin and isovitexin from the residue of extract of T.arvense leaves essential oil.The use of imidazole-type ionic liquids as solvents for the extraction of plant components had been a research hotspot in recent years,but the chemical structure of imidazole-type ionic liquids had potential soil environmental hazards.In order to avoid hazards,a variety of amino acid ionic liquids were prepared,and phenylalanine ionic liquids([Phe][HSO4])were selected as the suitable solvent for extracting isoorientin and isovitexin from T.arvense leaves.Under the optimal extraction conditions,the yields of isoorientin and isovitexin were 0.86±0.04 mg/g and 3.39 ± 0.09 mg/g,respectively.Compared with conventional methods,this process method had a higher extraction efficiency and was more environmentally friendly.Two different types of flavonoids of isoorientin and isovitexin extracted from T.arvense leaves were separated by a new type of magnetic borate-based metal-organic framework composite material(Fe3O4@SiO2(@BA-Zn-MOFs).The macroporous resin X-5 was used to preliminarily enrich the target components isoorientin and isovitexin in the extract of T.arvense leaves,and the desorption process was proceeded with 40%ethanol solution.The prepared magnetic borate-based metal-organic framework composites(Fe3O4@SiO2@BA-Zn-MOFs)were used for the adsorption of isoorientin and isovitexin as follows:adsorption time of 120 min,pH of 8,and adsorbent dosage of 10 mg.After being recycled for 5 times,the adsorption efficiency of the new synthetic materials on isoorientin could be more than 60%.The adsorption mechanism was that Fe3O4@SiO2@BA-Zn-MOFs captured isoorientin under alkaline conditions and formed a five-membered cyclic ester,and under acidic conditions,the five-membered cyclic ester was dissociated into the original substance,which realized the specific adsorption and separation of isoorientin.Ultrasound-assisted anti-solvent precipitation method was used to prepare nano-lignin from T.arvense rhizomes.The change trend of the influence of each experimental variable on the average particle size(LPS)of the obtained nano-lignin was determined by single factor experiments,and Plackett-Burman(PBD)and Box-Behnken design(BBD)were used to optimize the optimal conditions for preparing nano-lignin and the verification test was carried out,and the LPS of the prepared nano-lignin was 118± 3 nm.The nano-lignin samples prepared by the ultrasonic-assisted anti-solvent method were characterized including SEM,XRD,FTIR and TG.The results showed that compared with the untreated lignin,the nano-lignin prepared by this method was spherical,uniform and distributed.The structure was not destroyed.The solubility test showed that the lignin samples prepared by the ultrasonic-assisted anti-solvent method had stronger solubility.The antioxidant capacity test showed that the nano-lignin samples had higher free radical scavenging activity,which provided a broader space for the multi-faceted utilization of a type of herbal lignin with the structural characteristics of T.arvense lignin(p-hydroxyphenyl lignin).The inhibitory activity of essential oil from T.arvense leaves,seeds and its main component AITC on Penicillium expansum was studied.The results of inhibition zone,MIC and MBC determination and time lethal curve results showed that essential oil from T.arvense leaves,seeds and its main component AITC all had obvious inhibitory activity on P.expansum,and AITC had the strongest inhibitory activity against on P.expansum.The SEM observations of mycelial morphology revealed that compared with the hypha structure of the blank control on P.expansum,the hypha structure of on P.expansum after sample treatment was damaged to different degrees which showed different states like dryness,curling,shrinking and different thicknesses.It showed that essential oil from T.arvense leaves,seeds and AITC had highly effective inhibitory ability on P.expansum.The prepared AITC and nano-lignin-doped composite starch-based biodegradable film had both high tensile strength and elongation at break,which showed that it had good mechanical properties.The prepared AITC biodegradable film was used in the study of apple spoilage caused by Penicillium expansum,which showed that the coating of the biodegradable AITC film significantly inhibited the infection and growth of P.expansum.It had potential application value for the prevention and treatment of fruit spoilage caused by P.expansum.The residues extracted from T.arvense leaves,seeds and rhizomes were used to prepare Cr(VI)adsorbent to adsorb chromium ions in wastewater.The results of research on the main factors affecting the adsorption process(initial concentration of Cr(VI),pH and temperature)showed that a higher initial concentration of Cr(VI)could form a greater driving force in the adsorption system,which was beneficial for Cr(VI)to overcome the molecular resistance in the solution and be adsorbed on the adsorbent.The acidic conditions were more conducive to the adsorption of hexavalent chromium ions.The adsorbent had better adsorption effect at higher temperatures.The adsorption isotherm results showed that the adsorption process conformed to the Langumir adsorption model,indicating that the adsorption process was a single-layer adsorption.The results of adsorption kinetics fitting showed that the adsorption process conformed to the quasi-second-order kinetic model,and the adsorption process was chemical adsorption.The results of thermodynamic analysis showed that the adsorption process was a spontaneous endothermic process. |
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