Study On Structural Identification And Its Bioactivities Of Flavonoids From Pineapple Peels

Pineapple peel is a byproduct of pineapple processing, If not dealt with, will causeserious environmental pollution, and cause a great waste of resources. In this study, fullydevelop and utilizate waste resources of our province pineapple residue, and improve theirutilization, to accelerate the pace of building a modern high value of deep, comprehensiveutilization industrial pineapple processing in Guangdong Province. After extracting andpurifinGFlavonoids from pineapple peels residue, using a variety of ways in depth study ofits structure, then, to provide a theoretical basis for searching new antioxidant drugs, thepineapple peels flavonoids are conducted to do anti-oxidant capacity in vitro studies.Application of three different tumor cell line, provides the basis of the depth on health andmedicinal value of the development for the pineapple peels flavonoids1. By measuring, the fresh pineapple peels moisture content is86.4%, and ash, protein,crude fiber content is3.15%,3.75%,24.75%, respectively. The content of Ca, Mg isrelatively high in pineapple powder peels. The content of Ca is126.2mg/100g, and Mg is56.35mg/100g. Zn and Cu content are0.9819mg/100g and4921mg/100g. The standardequation of rutin standard curve is Y=0.0072X+0.0038, and the correlation coefficient R²is0.9995（R²>0.95）. Heat reflux extraction method, the cellulase extraction and ultrasonicassisted extraction method are used to extract pineapple peels flavonoids, respectively. Theextract content of heat reflux extraction method, cellulose-ethanol extract and ultrasonicassisted extraction method, respectively is1.93%,2.16%,2.13%in the optimumconditions of single-factor orthogonal experiment. Above the above method, the flavonoidscontent in pineapple peels is2.07%. And the purity of crude pineapple flavonoids is10.74%, in accordance with the purity calculation. After the crude pineapple peelsflavonoids purified by macroporous resin, the purity is35.65%. The pineapple flavonoidssamples can be roughly divided into three kinds of polarity of the components by makingsilica gel column chromatography, which are GF1, GF2, GF3. Their purity follow43.98%,65.70%and52.46%, respectively.2. Integration of the color reaction and fluorescent response identification results, wecan find pineapple peels flavonoids, which contain the types of flavonoids, flavonols,flavanone; The major findings are that flavonoids may contain sulfuric acid and aβ-glycosidic bond, when after comparing with the infraredspectrum of components; and itis inferred that the structure-based of the pineapple peels flavonoids may be the form ofglycosides; The structure of the pineapple peels flavonoids contains5-OH, no3-OH fromanalysis of the UV. So we can obtain that the structure of compounds may be5,7-dihydroxyflavone or its3-OH glycosides. The flavonoids of pineapple peels existing in theform of glycosides may be further inferred; according to mass spectrum analysis, the smallamount of substance which molecular weight is611.53, is likely to be the rutin hydrate ofthree water molecules; The peak in the mass spectrometric detection performance of611.52[M+H]⁺is likely to quercetin-3-0-New hesperetin of relative molecular mass610.52; For characterization mass spectrometry m/z627（M+1）465,303, they are two glycosidic flavonoids, so the pineapple contains flavonoids of two glycosidic flavonoids,as quercetin-3-O-beta-D-galactose-7-O-beta-D-glucoside; and303.43molecular ion peakis the peak of the highest peak in the spectra, and conclusions speculated IR spectra andUV map can be that the aglycone of relative molecularmass of302.43, while the pavilionskin pigment relative molecular mass is302.1, the preliminary view that the molecules ofthe brass aglycone quercetin for the pavilion; Pineapple flavonoids may contain the thesanshui rue leaf glucoside or quercetin-3-0-new Hesperetin. Loss of186molecular weightof molecular ion peak from the [M+H]⁺m/z498.17to m/z322.05, compared with aglucose-based relative molecular mass162is more14, which can be speculated that thepineapple peels flavonoids may be aglycone molecules connected to a glucosemonosaccharide molecules and m/z14groups; According to the size of the inference of therelative molecular mass, the groups may be-CH2-, so m/z322.05may be the base peakformed loss of glucose monosaccharide molecules base （m/z162）, and a methylene （m/z14）[M+H]⁺m/z498.17. m/z322.05by loss molecular weight for the17groups which may behydroxyl （-OH） formed the ion at m/z305.05peak, can be speculated that the pineapplepeels flavonoids molecule may contain a glucose ligands and a phenolic hydroxylstructure.3. DPPH standard curve for C_DPPH=4.7326×A₅₁₆+1.5144×10^-2was developed, andthe clearance of DPPH=1-C_DPPH/C₀×100%. Duration of different components ofscavenging DPPH free radicals from long to short size of the relationship as follows:silica gel column component GF2> silica gel column component of the GF1> silica gelcolumn component GF3> the pure flavoniods> rutin> the crude flavoniods and vitamin C.The effects of different components scavenging the DPPH radical showing significantdifferences, the order of the scavenging rate as follows: silica gel column GF2component>silica gel column GF1component> purified flavone> rutin> silica gel column GF3>crude flavone product> Vc. The size order of the clearance rate of superoxide anionradical (O^2-) as follows: GF2> GF1> purified flavonoids> rutin flavonoids crude> theGF3> Vc. The total antioxidant capacity order determination of several differentingredients when30ug/mL as follows: silica gel column GF2> silica gel column GF1>purified flavonoids> GF3by silica gel column> the crude product of flavonoids>rutin>Vc.4. The inhibition of Rue leaf glycosides and Vc on human lung cancer cell A549, as itsconcentration increases, the inhibition is the greater; and at a concentration of240ug/mL,the inhibition rates were58.6%and63.0%; While pineapple peels flavonoids withincreasing concentration, the inhibition on human lung cancer cell line A549did not showpositive linear correlation: concentration less120ug/mL, increasing concentration, thecrude and pure pineapple peels flavonoids, and silica gel column GF1, GF2, GF3component on the inhibition of human lung cancer cell line A549were tested to enhancethe effect, however, their concentration is240ug/mL, the inhibitory effect on human lungcancer cell line A549showed a declining trend. This shows the relationship that thepineapple peels flavonoids inhibitory rate is the stronger on human lung cancer cell lineA549, not with increasing concentrations; The inhibition rate of the order of human livercancer cell line SMMC-7721was as follows: leaf glycosides> rutin> GF2> GF1> pureflavonoids> GF3> crude flavonoids product> Vc, at a concentration of240ug/mL, theinhibition rate on hepatoma cells SMMC-7721was53.10%,49.90%,37.10%,36.70%, 30.80%,28.60%and5.20%, respectively; The order of inhibition rate on S-180sarcomacells in mice: leaf glycosides> GF3> pure flavonoids> crude flavonoids> GF1> GF2,the concentration of240ug/mL, the inhibition rate on the cells of murine sarcoma S-180followed:70.80%,60.50%,58.70%,46.50%,42.50%and32.10%, while the inhibition rateof240ug/mL Vc on the mouse fibrosarcoma cells S-180was45.80%.