Hibiscus sabdariffa L. (family Malvaceae), commonly known as bissap, karkade or roselle is a tropical plant native to India and Malaysia. The thick, red and fleshy, cup-shaped calyces of the flower are consumed worldwide as a cold beverage and as a hot drink (sour tea). Previous studies showed that H. sabdariffa possesses anti-tumoral, anti-oxidant and anti-hyperlipemic activities. [1, 2, 3] This present work was focused on quantifying the polyphenolic fraction, anthocyanins and other polar compounds in the aqueous extract of H. sabdariffa using two detection systems, i.e. RP-HPLC coupled to DAD or RP-HPLC coupled to ESI-TOF-MS. Seventeen compounds were successfully quantified and six of them were directly quantified by their corresponding standards, whereas the rest were indirectly quantified as equivalents using standards of similar compounds. The antioxidant capacity have also been estimated by comparing different in vitro methods, i.e. trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and measurement of thiobarbituric acid reacting substances (TBARS). H. sabdariffa showed high reducing capacity in FRAP assay and significant capability to scavenge peroxyl radicals by hydrogen atom transfer in the ORAC assay. Nevertheless, the extract exhibited poor efficacy to inhibit peroxyl radicals in lipid systems (TBARS). To further assess H. sabdariffa aqueous extract bioactivity, it was administered as sole drinking fluid to mice fed with a high fat-high cholesterol diet in order to assay its anti-hyperlipemic effects. The plant extract exhibited the capacity to decrease of 50% serum triglyceride concentration on hyperlipemic mouse model.
Quantification of the polyphenolic fraction and in vitro antioxidant and in vivo anti-hyperlipemic activities of Hibiscus sabdariffa aqueous extract
PASINI, FEDERICA;CABONI, MARIA;
2011
Abstract
Hibiscus sabdariffa L. (family Malvaceae), commonly known as bissap, karkade or roselle is a tropical plant native to India and Malaysia. The thick, red and fleshy, cup-shaped calyces of the flower are consumed worldwide as a cold beverage and as a hot drink (sour tea). Previous studies showed that H. sabdariffa possesses anti-tumoral, anti-oxidant and anti-hyperlipemic activities. [1, 2, 3] This present work was focused on quantifying the polyphenolic fraction, anthocyanins and other polar compounds in the aqueous extract of H. sabdariffa using two detection systems, i.e. RP-HPLC coupled to DAD or RP-HPLC coupled to ESI-TOF-MS. Seventeen compounds were successfully quantified and six of them were directly quantified by their corresponding standards, whereas the rest were indirectly quantified as equivalents using standards of similar compounds. The antioxidant capacity have also been estimated by comparing different in vitro methods, i.e. trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and measurement of thiobarbituric acid reacting substances (TBARS). H. sabdariffa showed high reducing capacity in FRAP assay and significant capability to scavenge peroxyl radicals by hydrogen atom transfer in the ORAC assay. Nevertheless, the extract exhibited poor efficacy to inhibit peroxyl radicals in lipid systems (TBARS). To further assess H. sabdariffa aqueous extract bioactivity, it was administered as sole drinking fluid to mice fed with a high fat-high cholesterol diet in order to assay its anti-hyperlipemic effects. The plant extract exhibited the capacity to decrease of 50% serum triglyceride concentration on hyperlipemic mouse model.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
