Study On The Preparation Of Soluble Dietary Fiber From Sunflower Receptacles And Its Effect On Anti-constipation

Constipation is a common functional gastrointestinal disease.There are many and complex causes of constipation.Lack of exercise,changes in diet structure,oxidative stress and other factors can cause constipation.Constipation often brings great pain to patients,even induces colon cancer,threatening life.Studies have found that dietary fiber(DF)is often used as the water carrier of feces,which can increase the volume of feces and play a certain therapeutic effect on constipation.Dietary fiber can be divided into soluble(SDF)and insoluble(IDF)according to solubility.SDF has good water binding capacity,can increase fecal weight and water content,more conducive to fecal discharge;in the intestine can be degraded into short chain fatty acids,reduce intestinal p H;in addition,it can also ferment to produce gas products such as methane and CO₂,stimulate intestinal mucosa,enhance intestinal peristalsis,and alleviate constipation.According to the Great Dictionary of Traditional Chinese Medicine,sunflower disc has the efficacy of treating vertigo,migraine,asthma,and functional uterine bleeding.There are many active substances in sunflower disc,such as flavonoids,volatile oil and chlorogenic acid,which have been widely studied.However,the development and utilization of SDF in sunflower disc has not been reported.Therefore,sunflower discs(Helianthus annuus L.)were used as experimental materials in this study to extract SDF from sunflower discs by different methods.The structural characterization,physical and chemical properties,anti-oxidation,and intestinal laxative function of SDF from sunflower discs were scientifically studied,providing a scientific basis for the development and utilization of SDF from sunflower discs in the future.Firstly,the extraction processes of hot water extraction,citric acid extraction and cellulase extraction were optimized by response surface methodology.The optimum conditions for the extraction of soluble dietary fiber(WSDF)from sunflower disc by hot water extraction were as follows:1:34 g/m L solid-liquid ratio,extraction temperature 81°C,and extraction time 119 min.Under these conditions,the yield of WSDF was the highest,which was 13.17±0.21%.The optimal conditions for obtaining soluble dietary fiber(ASDF)from sunflower disc by citric acid extraction were as follows:solid-liquid ratio of 1:21 g/m L,temperature of 68°C,acid addition of 1%,and extraction time of 96 min.Under these conditions,the yield of ESDF was the highest 13.64±0.27%.The optimum extraction conditions of soluble dietary fiber(ESDF)were as follows:solid-liquid ratio of 1:27 g/m L,temperature of 56°C,enzyme dosage of 1.7%,extraction time of 84 min.The extraction rate of ESDF was15.29±0.22%.The above process laid a solid foundation for the extraction of SDF from sunflower disc in the future.Secondly,the structures of SDF from three sunflower discs were characterized by Fourier transform infrared spectrometer,scanning electron microscope and XRD diffractometer.The results showed that the functional groups of SDF from three sunflower discs were roughly similar,but the peak intensities were slightly different.Different extraction methods had great influence on the surface structure of SDF from sunflower disc,and the WSDF surface showed irregular fibrous and lamellar coexistence.The surface of ASDF is serrated with many small pores.The ESDF surface presents irregular fiber columnar.In addition,studies have shown that they are amorphous structures.Subsequently,the physicochemical properties and antioxidant properties of SDF from three sunflower discs were evaluated.The physicochemical properties were as follows:the water holding capacities of WSDF,ASDF and ESDF were 2.67±0.11 g/g,4.40±0.11 g/g and 3.31±0.35 g/g,respectively.The expansion forces were 3.33±0.17m L/g,5.57±0.26 m L/g and 4.23±0.25 m L/g,respectively.The oil holding capacity was 2.05±0.20 g/g,2.50±0.16 g/g,2.38±0.21 g/g,respectively.DPPH,ABTS radical scavenging and iron reduction experiments were used to study their antioxidant capacity.The results showed that SDF from three sunflower discs had certain antioxidant capacity,and ESDF had the strongest antioxidant capacity.Since ASDF has better water holding capacity,expansion capacity and certain antioxidant capacity,ASDF was selected for the study of intestinal laxative function in this paper.Finally,the constipation model was established by loperamide hydrochloride,and the low,medium and high ASDF dose groups were set to study the improvement of related indicators in constipation mice.It was found that the fecal weight of the three dose groups of ASDF was significantly increased compared with the model group.The middle and high doses of ASDF had significant effects on the first black stool discharge time,which greatly shortened the discharge time.In addition,it also significantly increased the moisture content of feces.The high dose of ASDF significantly improved the intestinal propulsion ability of constipation mice.From the HE staining of colon tissue,ASDF three dose groups can improve the damage of colon tissue in constipation mice to a certain extent.This study found that sunflower dish SDF has good laxative effect,which provides a reliable scientific basis for the future research and development of functional health food.