Bamboo-leaf-flavonoids And Its Activities From Phyllostachys Pubescens And Pleioblastus Argenteastriatus

Bamboo-leaf-flavonoids are main functional components in bamboo leave extract. It isreported that bamboo-leaf-flavonoids have many kinds of activities and wide applications inthe future. Taking the leaves of Phyllostachys pubescens and Pleioblastus argenteastriatus asthe experiment materials, Some flavones were separated with Silica gel column and SephadexLH-20 column, and were identified with MS, UV, FTIR and NMR. The purification technicsand content determination of bamboo-leaf-flavonoids also were researched. The antioxidationeffects and the antifungal effects of bamboo leave extract were tested. The results were asfollows:(1) Extracting compounds from Phyllostachys pubescens leaves (1000g) with 95%ethanol reflux method.Then the extraction were partitioned with Pet.Et, EtOAc, and n-BuOHrespectively. The extraction with EtOAc and n-BuOH was isolated by silica gel columnchromatography, Sephadex LH-20 and RP-18. Five compounds were isolated: compound 1:tricin-7-O-glucoside, 18.5mg; compound 2: luteolin-6-C-glucoside(isoorientin), l18.4mg;compound 3: apigenin-6-C-glucoside (isovitexin), 86.7mg; compound 4: flavonoid, structureis not identified, 32.8mg; compound 5: tricin, 44.3mg.(2) Extracting compounds from Pleioblastus argenteastriatus leaves (961g) with 95%ethanol soakagemethod. Extraction was purified by AB-8 macroporous absorption resin. Then20% ethanol, 40% ethanol, 60% ethanol, 80% ethanol, acetone eluted.The elution were isolatedby Sephadex LH-20 and RP-18. Ten compounds were isolated: compound 6: tricin,107.4mg; compound 7: luteolin-7-O-glucoside, 5mg; compound 8: structure is not identified,1mg; compound 9 : luteolin-6-C-digitoxoside-7-O-glucoside, 29.6mg;compound 10 :flavonoid, structure is not identified, 30.8mg; compound 11: tricin-7-O-glucoside, 10mg;compound 12 : flavonoid, structure is not identified, 332.5mg; compound 13:luteolin-6-C-rutinoside, 449.3mg; compound 14: structure is not identified, 66.7mg; compound15: structure is not identified, 5mg.(3) Extracting compounds from Phyllostachys pubescens leaves (30g) with 95% ethanol ultrasonic method, six crafts of extraction and purification technics for bamboo-leaf-flavonoidswere compared, and the best craft was polyamide adsorption method: Bamboo leave extract→the concentrated solution→Mixing polyamide into polyamide column→Water elutes→Eluted by 70% ethanol until can not examine the flavones→Elution liquid→Reducingpressure concentration to 100mL→Determining bamboo-leaf-flavonoids content. Thespectrophotometric and HPLC method were compared. The result indicated: Both of themwere reliable method to determine bamboo-leaf-flavonoids, the determining results ofspectrophotometric method was a little higher than HPLC.(4) Extracting compounds from Phyllostachys pubescens leaves (6000g) with 95%ethanol reflux method. Extraction was partitioned with AB-8 macroporous absorption resin, theorder of elution solvent was water, 20% ethanol, 40% ethanol, 60% ethanol, 80% ethanol andacetone, we gotM20, M40, M60, M80, MA after being evaporated , and P40, P60, P80,PA came from (2), TBHQ and BHT were synthetical antioxidant, their antioxidation activitieswere evaluated by means of scavenging DPPH.Studied on solution absorption spectrum of DPPH, absorbency value change after addingTBHQ, BHT, M40 into DPPH reaction system, relation between DPPH concentration andabsorbency value, conclusions were as follows: the spectrophotometric parameter todetermine the effect of scavenging DPPH were as follows:λmax=518.4nm, reaction time was40 min. We evaluated antioxidation activities by IC₅₀(antioxidant concentration whenscavenging rate hit 50%), samples' IC₅₀ were as follows: TBHQ (21.14mg/L) , BHT(42.09mg/L) , M20 (141.11 mg/L), M40 (108.40 mg/L), M60 (177.38 mg/L), M80(268.21 mg/L), MA (837.67 mg/L), P40 (173.26 mg/L), P60 (319.82 mg/L), P80 (519.67mg/L), PA (364.50mg/L), According to scavenging rate of these samples, the order fromstrong to weak was as follows: TBHQ＞BHT＞M40＞M20＞M60＞P60＞P40＞PA＞P80＞MA, the three samples among them , M20 M40 M60, had the strongest antioxidationactivities, compared with BHT, scavenging ability of M20, M40, M60 hit 29.86%, 38.85%,23.73% of BHT.(5) By the method of scavenging O₂^·- to evaluate antioxidation activities of M20, M40,M60, M80, MA, TBHQ.We studied on absorption spectrum of oxidation product, and the effect of V₀, pyrogallol concentration and pH of Tris-HCl on scavenging rate. Thespectrophotometric parameter to determine the effect of scavenging O₂^·- were as follows:λmax=319.5nm, determination should be done at the end of the first minute, one time everyminute and for nine times, V₀=0.035, adding 0.3mL pyrogallol into reaction system,pH=8.2. We evaluated antioxidation activities by IC₅₀(sample concentration atY=50%),samples' IC₅₀ were as follows: M20(402.56 mg/L), M40(298.69mg/L), M60(352.68mg/L),M80 (320.58mg/L) , MA (459.68rag/L) , TBHQ (95.01mg/L) . According to scavengingrate of these samples, the order from strong to weak was: TBHQ＞M40＞M80＞M60＞M20＞MA. When scavenging rate hit 50%, compared with TBHQ, scavenging ability of M20,M40, M60, M80 and MA hit 23.60%, 31.81%, 26.94%, 29.64%, 20.67% of TBHQ.(6) By the method of scavenging hydroxyl radical to evaluate antioxidation activities ofM20, M40, M60, M80, MA, TBHQ.According to the absorption spectrum of the redcompound, which was produced by Fe²⁺ and phenanthroline, as well as the effect of scavenginghydroxyl radicals, the conclusions were as follows: The spectrophotometric parameter todetermine the effect of scavenging hydroxyl radical was as follows:λmax=509.1nm; Whenscavenging rate hit 50%, the concentration of all samples were far higher than TBHQ. Whenscavenging rate hit 70%, compared with TBHQ, scavenging ability of M20, M40, M60,M80 and MA hit 33.54%, 40.55%, 39.36%, 22.36%, 3.35% of TBHQ.According to scavengingrate of these samples, the order from from strong to weak was: TBHQ＞M40＞M60＞M20＞M80＞MA.(7) Studied on adding M40, M60, P40, P60, TBHQ, BHT into lard, and then keepinglard temperature at 70℃, the results indicated: M40, TBHQ, BHT have obvious antioxidationeffect. M40 almost have the same effect as TBHQ and BHT. M60,P40,P60 also had someantioxidation effects.(8) Taking M20,M40,M60,M80,MA as sample, studied their antifungal activities toFusarium spp, Colletotrichum gloeosporioides Penz and Fusarium oxysporum Schlechtendahl.Takeing P40,P60,P80,PA as sample, studied their antifungal activities to Fusarium spp. Theresults indicated: M20,M40,M60,M80,MA have obvious antifungal activities.After 48h,EC₅₀ values of those samples to show best antifungal activities on Fusarium spp, Colletotrichum gloeosporioides Penz and Fusarium oxysporum Schlechtendahl were asfollows: M20 (1.10g/L) , MA (0.49g/L) , M80 (0.704g/L) , After 72h, MA (0.75g/L),MA (1.28g/L) , M80 (2.3g/L). P40,P60,P80,PA (10 g/L) , those samples have obviousantifungal activities on Fusarium spp. P80 was the best one, antifungal rate could achieve98.8% after 120h.