Study On The Extraction And Purification Of Hesperidin From Pericarpium Citri Reticulatae And The Comprehensive Utilization Of The Residue

As an edible traditional Chinese medicine, Pericarpium Citri Reticulatae is rich in manyfunctional ingredients, such as essential oil, pigment and flavone. At present, the major way ofits development and utilization was to extract and separate the functional ingredients. Afterthe extraction, the residue was rejected, which caused the waste of resources andenvironmental pollution. In this paper, the extraction and purification of hesperidin fromPericarpium Citri Reticulatae strips and the processing technology of preserved tangerinepeel with the strip residues were studied. The main contents are described as follow:Firstly, the extracting techniques of hesperidin by ethanol refluxing and continuoussubcritical water were studied. The single factor experiments and the orthogonal tests weredone to optimize the ethanol refluxing extracting conditions as follows:75%(v/v) ethanolrefluxing at85℃for2.5h, and the ratio of material to extracting liquid was1:35(w/v).Under these conditions, the extracting yield of hesperidin was3.31±0.07%. And thecontinuous subcritical water extraction was also studied. Results revealed that for50.0gmaterial, a maximum hesperidin yield of3.65%was achieved, with subcritical water at150℃,6MPa,50mL/min for90min.Secondly, the purification technology of hesperidin was studied.1.0g crude extract waswashed by100mL95%ethanol at stirring rate of200r/min for20min, then cooled and keptat4℃for4h, The ethanol washing was repeated twice, followed by once distilled waterwashing with the same dosage, stirring rate and time. The purity and recovery rate of the finalproducts were94.1±1.1%and73.4±2.2%, respectively.It was indicated that the ultraviolet absorption of the ending product was consistent withthe standard through ultraviolet spectral scanning, they both had characteristic absorptionpeaks at210nm and284nm. Using Differential Scanning Calorimetric technology verifiedthe melting point of hesperidin was257.6℃, which was the same with the report of literatures.HPLC-MS showed the retention time of the ending product corresponded with the standard at5.29min (column: BEH C18；mobile phase: methanol-0.1%formic acid (40:60, v/v))；Andthe molecular weight of hesperidin was610.2dalton, which in agreement with the data of therelative references.At last, the preparation method of the preserved tangerine peel with the hesperidinextraction strip residues was studied. Filling increased the satiation of the product. The bestconcentration of filler agar was0.5%. And the optimum content for sugar osmosis were asfollows:40%(w/w) sugar,0.8%citric acid,1.0%NaCl, and0.3%orange essence, soaking for12h at40℃By sealed packing and adding0.04%potassium sorbate, the products could bepreserved for12month. The self-made preserved tangerine peel product was compared with the market sell product. The results showed that the L*(whiteness) and b*(yellowness) of theself-made product were higher, and the a*(redness)was lower, in addition, the hardness waslower and the springiness was higher than the sold product, and the sensory score of the madeand sold products were93.5and94.4, respectively.