Quercetin and quercetin glycoside d

Quercetin and quercetin glycoside derivatives present in different
varieties of onions were extracted using the mixture of
MeOH: formic acid: water (MFW; 50:5:45; v/v/v) containing
the antioxidant TBHQ (tert-butylhydroquinone, 2 g/L)
(Pe´rez-Gregorio et al., 2010). To improve the extraction efficiency
of quercetin glycosides in onions, the samples were treated
with a higher concentration of hydrochloric acid (6 M).
The total extraction process was repeated four times which
increases the efficiency of releasing the quercetin from the lyophilized
powder. HPLC analyses of quercetin glycosides were
conducted by slightly modified method in buckwheat flavonoids
(chlorogenic acid, orientin, isoorientin, vitexin, isovitexin,
rutin, and quercetin) (Kim et al., 2006). Each
quercetin glycosides were characterized based on the chromatographic
retention time and UV–Vis wavelength data by
comparing the previously identified quercetin glycosides
(Sellappan and Akoh, 2002). The quercetin glycoside derivatives
found in onions were similar which coincided with previously
published data (Sellappan and Akoh, 2002). HPLC
analysis guided to exhibit four peaks with different retention
time. The HPLC chromatogram of red onion, yellow onion
and chartreuse onion extracts recorded in 360 nm is shown
in Figs. 1–3.

Hasil (Bahasa Indonesia) 1:

Quercetin dan quercetin glikosida derivatif hadir dalam berbagaivarietas bawang yang diekstrak menggunakan campuranMeOH: formic asam: berisi air (MFW; 50:5:45; v/v/v)antioksidan TBHQ (tert-butylhydroquinone, 2 g/L)(Pe´rez-Gregorio et al., 2010). Untuk meningkatkan efisiensi ekstraksidari quercetin glikosida di bawang, sampel diperlakukandengan konsentrasi yang lebih tinggi dari asam klorida (6 M).Proses ekstraksi total diulang empat kali yangmeningkatkan efisiensi penggunaan melepaskan quercetin dari diliposiskanbubuk. Analisis HPLC quercetin glikosida yangdilakukan oleh sedikit diubah metode dalam soba flavonoid(asam klorogenat, orientin, isoorientin, vitexin, isovitexin,rutin, dan quercetin) (Kim et al., 2006). Masing-masingQuercetin glikosida ditandai berdasarkan kromatografiwaktu retensi dan UV-Vis panjang gelombang data olehmembandingkan glikosida quercetin sebelumnya diidentifikasi(Sellappan dan Akoh, 2002). Quercetin glikosida derivatifditemukan di bawang adalah serupa yang bertepatan dengan sebelumnyadata diterbitkan (Sellappan dan Akoh, 2002). HPLCAnalisis dipandu menunjukkan empat puncak dengan penyimpanan yang berbedawaktu. Chromatogram HPLC bawang merah bawang merah, kuningdan bawang chartreuse ekstrak tercatat dalam 360 nm ditampilkanrajah -rajah 1-3.