Resumo (PT):
The present study reports for the first time the metabolite profile and antioxidant activity of aqueous extract obtained from Dracaena draco L. leaf. Volatiles profile was determined by HS-SPME/GC-IT-MS, with 34 compounds being identified, distributed by distinct chemical classes: 2 alcohols, 5 aldehydes, 16 carotenoid derivatives and 8 terpenic compounds. Carotenoid derivative compounds constituted the most abundant class in leaf (representing 45% of total identified compounds). Phenolics profile was determined by HPLC/DAD and 9 constituents were identified: 2 hydroxycinnamic acid derivatives – 5-O-caffeoylquinic and 3,5-O-dicaffeoylquinic acids; 4 hydroxycinnamic acids – caffeic, p-coumaric, ferulic and sinapic acids and 3 flavonol glycosides – quercetin-3-O-rutinoside, kaempferol-3-O-glucoside and kaempferol-3-O-rutinoside. The most abundant phenolic compound is quercetin-3-O-rutinoside (representing 50.2% of total polyphenols). Organic acids composition was also characterised, by HPLC–UV and oxalic, citric, malic and fumaric acids were determined. Oxalic and citric acids were present in higher amounts (representing 47%, each). The antioxidant potential of this material was assessed by the ability to protect against free radical-induced biomembrane damage, using human erythrocyte as in vitro model. Leaf extract strongly protected the erythrocyte membrane from haemolysis (IC50 of 39 ± 11 μg/ml), in a time- and concentration-dependent manner. This is the first report showing that D. draco leaf is a promising antioxidant agent.
<br>
<br>
Keywords: Dracaena draco leaf; Volatiles; Polyphenols; Organic acids; Haemolysis inhibition; Antioxidant activity
<br>
<a target="_blank" href="http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T6R-50H1WV8-4&_user=2460038&_coverDate=02%2F01%2F2011&_rdoc=33&_fmt=high&_orig=browse&_origin=browse&_zone=rslt_list_item&_srch=doc-info(%23toc%235037%232011%23998759996%232414757%23FLA%23display%23Volume)&_cdi=5037&_sort=d&_docanchor=&_ct=89&_acct=C000057398&_version=1&_urlVersion=0&_userid=2460038&md5=3e7fd5f638688da2f882ce9fac743216&searchtype=a"> texto integral</a>
<br>
<br>
Abstract (EN):
The present study reports for the first time the metabolite profile and antioxidant activity of aqueous extract obtained from Dracaena draco L leaf. Volatiles profile was determined by HS-SPME/GC-IT-MS, with 34 compounds being identified, distributed by distinct chemical classes: 2 alcohols, 5 aldehydes, 16 carotenoid derivatives and 8 terpenic compounds. Carotenoid derivative compounds constituted the most abundant class in leaf (representing 45% of total identified compounds). Phenolics profile was determined by HPLC/DAD and 9 constituents were identified: 2 hydroxycinnamic acid derivatives - 5-O-caffeoylquinic and 3,5-O-dicaffeoylquinic acids; 4 hydroxycinnamic acids - caffeic, p-coumaric, ferulic and sinapic acids and 3 flavonol glycosides - quercetin-3-O-rutinoside, kaempferol-3-O-glucoside and kaempferol-3-O-rutinoside. The most abundant phenolic compound is quercetin-3-O-rutinoside (representing 50.2% of total polyphenols). Organic acids composition was also characterised, by HPLC-UV and oxalic, citric, malic and fumaric acids were determined. Oxalic and citric acids were present in higher amounts (representing 47%, each). The antioxidant potential of this material was assessed by the ability to protect against free radical-induced biomembrane damage, using human erythrocyte as in vitro model. Leaf extract strongly protected the erythrocyte membrane from haemolysis (IC(50) of 39 +/- 11 mu g/ml), in a time- and concentration-dependent manner. This is the first report showing that D. draco leaf is a promising antioxidant agent.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
8