ANTIOXIDANTS ACTIVITY OF EXTRACTS FROM SAMBUCUS NIGRA, EFFICIENCY OF DIFFERENT EXTRACTION METHODS

Abstract

Sambucus nigra is a medicinal plant used in traditional medicine for the treatment of various diseases. Researches in the recent past have accumulated enormous evidences revealing S. nigra plant to be an excellent source of antioxidants. The effects of three extraction methods (percolation, Soxhlet and ultrasonically assisted extraction) on the total phenolic (TPC), total flavonoid (TFC) contents and antioxidant activities (AAs) of S. nigra fruit, leaf and bark were investigated. TPC and TFC were determined using the Folin-Ciocalteu and aluminum chloride methods, respectively. While AAs were evaluated using iron chelating ability, 2, 2-diphenyl1-picrylhydrazyl (DPPH), nitric oxide and hydrogen peroxide radical scavenging activities. TPC ranged from 72.0 to 185.6 mg gallic acid equivalent (GAE)/g of the extract. The ultrasonic extract of leaf had a higher TPC than the other extracts. TFC ranged from 19.6 to 109.5 mg QE/g of the extract. Percolation extract of leaves had a higher TFC than the other extracts. In the DPPH test, the ultrasonic extracts had a higher activity than the other methods. The ultrasonic extract of leaf showed the best activity (IC50 = 21.6 ± 1.1 µg ml-1). The ultrasonic extracts had a higher NO radical scavenging activity, too. The ultrasonic extract of leaf showed the best activity (IC50=13.2 ± 0.9 µg ml-1). It was significantly more potent than quercetin, which has been used as a standard (IC50=155.0 ± 6.4 μg ml-1) (p< 0.001). Only the ultrasonic extracts showed the chelating activity. The ultrasonic extract of bark had the best activity (IC50 = 115.5 ± 9.7 µg ml-1). The extracts were capable of scavenging H2O2 in a concentration dependent manner. The ultrasonic extract of fruit showed the best activity (IC50 = 61.7 ± 2.8 µg ml-1). No correlations were found between H2O2, NO, DPPH radical scavenging activities and TPC. The results obtained indicated that the ultrasonic method could effectively extract antioxidants from this plant.