PURIFICATION AND ANTIOXIDANT ACTIVITY OF ALOE VERA LEAF LECTIN

SUMMARY A new and rapid affinity chromatography method based on cyanogen bromide (CNBr)-activated Sepharose 4B bound-ovalbumin is presented for the purification of the main lectin present in Aloe vera (L.) Burm. fil. The lectin was purified 60 fold to apparent homogeneity in native polyacrylamide disc gel electrophoresis (PAGE) showing an apparent molecular weight of 45000 kDa. The fact that sodium dodecyl sulfate (SDS)-PAGE gave a subunit molecular weight of 14 400 kDa tends to propose that the lectin is composed of three subunits and thus is in agreement with Aloctin I previously partially purified and characterized by us. The lectin did not exhibit antioxidant effect as assessed by the DPPH· radical-scavenging assay. OZET Aloe vera (L.) Burm. fil. lektinin saflastirilmasi icin, yeni ve hizli bir kromatografi yontemi olan, ovalbumin bagli-siyanojen bromur (CNBr) ile aktive edilmis Sefaroz 4B, afinite kromatografisi tanitilmaktadir. Lektin, kromatografi sonucunda 60 kez saflastirildi. Poliakrilamid disk jel elektroforezi (PAGE) ile homojen oldugu gozlemlenen lektinin molekul agirligi bu yontemle, 45 000 kD olarak saptandi. Sodyum dodesil sulfat (SDS)-PAGE ile altbirim molekul agirligi 14 400 kDa olarak belirlenen lektinin, uc alt birimden olustugu ve bunun da daha once tarafimizdan kismen saflastirilmis ve karakterize edilmis olan Aloctin I ile uyum icinde oldugu sonucuna varildi. Saflastirilan lektin, DPPH· radikal supurme tayini ile degerlendirildiginde antioksidan etki gostermedi. Key words: Aloe vera, lectin, purification, affinity chromatography, antioxidant activity.