The Preparation Technology And Anti-obesity Activity Of Fermented Barley Extracts With Lactic Acid Bacteria

With the gradual improvement of people’s living standards,people more and more like refined and high-calorie diet,which let dyslipidemia-based obesity become a global problem.In order to effectively treat obesity,finding a lipid-lowering material from the natural food has become the research hotspot in current functional food industry.Barley is a traditional crop,which has amount of antioxidant,anti-aging and lipid-lowering nutrients,so barley not only corresponds to "three high and two low" type of functional food requirements,but is known as the grain Full price food.Moreover,the nutrients,proportion and digestibility of barley are significantly improved,and appear a stronger beneficial life function after fermentation.In this paper,barley flour was used as fermentation substrate,and Lactic Acid Bacteria were used as the fermentation bacteria.Then,screened excellent species of barley and bacteria,and optimize the process of Lactic Acid Bacteria fermented barley;The obese rat model was established to study the effect of Lactobacillus fermented barley extract(LFBE)on obesity and research the metabolic pathway of LFBE in vivo;Used β-cyclodextrin to improve LFBE stability,and studied the effect and mechanism of β-cyclodextrin in embedding barley;Optimized the addition of auxiliary in LFBE tablets,and evaluated the direct-pressed feasibility of the freeze-dried powder of Lactobacillus fermented barley extract(LFBEP)through SeDeM system,and researched the quality of LFBE tablets in storage period.The main research contents and results were shown as follows:1.Study on process of Lactic Acid Bacteria fermenting barley powder.The contents of crude protein,crude polysaccharide,free polyphenol,β-glucan,ash and humidity in LFBEP were determined by the method of national standard.The varieties of barley and bacteria were screened by grey correlation method.The free polyphenols and soluble protein content were as a process optimization index,and designed single factor and response surface test to optimize fermentation process.The results showed that Yangsi 3 barley and Lactobacillus plantarum Dy-1 were the best choice to prepare LFBEP.The optimum fermentation process was as follows: solid-liquid ratio,the amount of direct adding bacteria,initial pH,the fermentation temperature and fermentation time were 1:7,8×107cfu/g,5.0,34 ℃ and 28 h,respectively.2.The lipid-lowering effect and metabolic pathway of Lactobacillus plantarum fermentation barley extract.The fat rats were fed with 800 mg/kg/ day LFBEP for 10 weeks to study the effect of LFBEP in improving lipid metabolism,reducing the weight of adipose tissue and increasing the expression of lipid metabolism.The results showed that LFBEP could significantly inhibit the weight gain,decrease the levels of triglyceride,cholesterol and low density cholesterol in scrum,decrease the weight of white fat,and significantly improve the dyslipidemia of obese rats.LFBEP enhances the energy consumption of brown adipose tissue in rats by increasing the expression of UCP1,PGC-1α,COX and other associated mitochondria in the brown adipose tissue and epididymal adipose tissue.Moreover,LFBEP induced the browning of the epididymal adipose tissue and accelerated the body fat consumption,thus achieve the effect of inhibiting obesity.3.The embedding effect of β-Cyclodextrin on improving stability of Lactobacillus plantarum fermentation barley flour extract.The embedding effects of β-cyclodextrin(β-cd)on the oxidation activity of LFBE were studied.Fourier transforms infrared spectroscopy,scanning electron microscopy,X-ray diffraction and GC-MS were used to study the effect and mechanism of β-cd on embedding LFBE.The results showed that 1.6% β-cd significantly protected the DPPH and ·OH radical scavenging ability of LFBE,and prevented the browning of LFBE.The small molecule of LFBE entered the β-cd cavity,and turned disperse flocculent structure of LFBEP to the partial crystal structure.The embedment of β-cd also reduced the loss of volatile components in LFBEP and increased the stability of LFBEP.4.The direct-pressed feasibility of LFBE-β-cd was evaluated with the SeDeM system,and then researched the storage quality of LFBE-β-cd tablets.The single factor test was used to optimize the amount of sodium carboxymethyl starch and magnesium stearate.Twelve indexes of LFBE-β-cd were evaluated by SeDeM system.Studied direct-pressed feasibility of LFBE-β-cd and researched the storage of LFBE-β-cd tablets.The results showed that: 2% sodium carboxymethyl starch and 1% magnesium stearate let LFBE-β-cd had better disintegration and silty fluidity.IP = 0.92> 0.5 and IGC =7.0>5,so LFBE-β-cd was suitable for direct compaction;The hardness of LFBE-β-cd tablets had no significant change within 3 months at room temperature or accelerated storage,but appeared browning in accelerated storage tests,so LFBE-β-cd tablets shall be stored at room temperature or cool environment,and the shelf life of LFBE-β-cd tablets was 3 months.