Ultrasound-assisted extraction of antioxidant polyphenolic compounds from Nephelium lappaceum L. (Mexican variety) husk


Aide Saenz Galindo


Objective: To reach the recovery and identification of antioxidant polyphenolic compounds
from Nephelium lappaceum L. (Mexican variety) husk using ultrasound-assisted extraction
and liquid chromatography/mass spectrometry as well as the in vitro antioxidant activity.
Methods: Rambutan husk extracts were obtained by ultrasound-assisted extraction, mass/
volume ratio, water/ethanol percentage and extraction time were evaluated. Once the best
extraction condition of polyphenolic compounds was defined, a polyphenolic fraction was
recovered using Ambetlite XAD-16. The total content of antioxidant polyphenolic compounds
was determined by summation of the total hydrolysable polyphenol and total condensed
polyphenol contents. Recovered compounds were identified by FTIR (ATR) spectroscopy and
HPLC/ESI/MS. The antioxidant activity was carried out by ABTS, DPPH and lipid oxidation
inhibition in vitro methods. Results: In Mexican variety rambutan husk, the total polyphenolic
content was 487.67 mg/g, after ultrasound-assisted extraction. According to the HPLC/ESI/MS
analysis 12 antioxidant polyphenolic compounds were identified, mostly ellagitannins such
as geraniin, corilagin and ellagic acid. The antioxidant activity determined by ABTS, DPPH
and lipid oxidation inhibition methods was demonstrated. The main functional groups of the
identified compounds were determined by FTIR analysis. Conclusions: It was demonstrated
that ultrasound-assisted extraction was effective and allowed the extraction and recovery of
antioxidant polyphenolic compounds. Furthermore Mexican variety rambutan husk is an
important source for recovering polyphenolic compounds with antioxidant activity, these
compounds have potential application for the treatment/prevention of various diseases related
to cancer and pathogenic microorganisms.

Artículo- ASG 2 2018