The Preparation And Functional Properties Of Nano Cellulose Perilla Straw

Perilla(Perilla frutescens)straw contain up to 62.7% cellulose and hemicellulose,which are rich in nutrients and contain a variety of active ingredients but are frequently discarded or burned,resulting in a significant waste of resources.In this study,cellulose was extracted from perilla straw by choline chloride/urea deep eutectic solvent(DES)method,and nanocellulose was prepared by ultrasound-assisted choline chloride/oxalate DES,and its morphology,structure and physicochemical properties were analyzed by SEM,FT-IR,XRD,and TG.The hypoglycemic and hypolipidemic functional properties were investigated through in vitro simulated digestion.The findings of the study may provide a technical basis and theoretical reference to enrich the source of nanocellulose materials and improve the utilization of perilla straw resources.The most important findings of the research are as follows:(1)The raw material for the extraction of cellulose from Perilla straw was choline chloride/urea DES.Response surface optimization was used to determine the optimal extraction process conditions based on the single-factor experiments: material-liquid ratio of 1:21,reaction temperature of 121°C,and reaction time of 4 h.The cellulose extract yield was 65.3%,with a cellulose content of 73.82% under these conditions.The structural analysis and property characterization showed that the extract’s microstructure was more sparse and porous than that of perilla straw,with considerably improved crystallinity and thermal stability.(2)Using ultrasound-assisted choline chloride/oxalate DES,the nanocellulose was made from perilla straw cellulose.By combining single-factor and response surface analysis,the optimum process conditions for the preparation of perilla straw nanocellulose were determined: reaction temperature 83°C,reaction time 1.6 h,material-liquid ratio 1:20,sonication time 28 min,and sonication power 400 W.The yield of perilla straw NCC reached90.2% under optimal extraction conditions.(3)The results of the structural,physicochemical,and functional properties of perilla straw nanocellulose revealed that,when compared to perilla straw cellulose,the perilla straw nanocellulose was loose and porous with a median particle size of 213 nm and retained the type I crystal morphology,but the thermal stability,water holding capacity,oil holding capacity,emulsification activity,and nitrite ion and cation exchange capacity were significantly higher.Perilla straw nanocellulose had higher water and oil holding capacity and nitrite ion adsorption capacity than wheat straw nanocellulose,but lower emulsification activity and cation adsorption capacity.(4)In comparison to perilla straw cellulose,wheat straw cellulose,and wheat straw NCC,perilla straw nanocellulose had the greatest glucose adsorption capacity,according to the study’s findings on the impact of perilla straw nanocellulose on postprandial glucose concentration.Perilla straw NCC had a significantly greater capacity to obstruct glucose diffusion than wheat straw NCC.The inhibitory capacity of perilla straw NCC on α-amylase activity and α-glucosidase activity was 66.17% and 58.11%,respectively,when the sample concentration was 1.6 mg/m L,and the starch digestibility was decreased to 40.2%.Both perilla and wheat straw NCC demonstrated a significant concentration dependence in reducing glucose release,according to in vitro starch digestion studies,but perilla straw NCC had a greater starch digestibility than wheat NCC.(5)The cholesterol binding capacity of perilla straw NCC under neutral conditions was greater than that under acidic conditions,as demonstrated by vitro binding capacity and cholesterol-lowering activity.In comparison to wheat straw NCC,perilla straw NCC had a considerably higher capacity to absorb cholesterol at p H 2.0.Perilla straw cellulose,perilla straw NCC,wheat straw cellulose,and wheat straw NCC had different bile acid and sodium cholate adsorption capacities,and the adsorption capacity size varied: Perilla straw NCC>wheat straw NCC>perilla straw cellulose>wheat straw cellulose,in that order.With increasing concentration,the inhibitory activity of perilla straw NCC on pancreatic lipase steadily grew and was noticeably stronger than that of wheat straw NCC.The total amount of free fatty acids released from NCC of perilla straw increased and then decreased with concentration,which was higher than the release rate of NCC of wheat straw.