Quantification of Amygdalin in Nonbitter, Semibitter, and Bitter Almonds (Prunus dulcis) by UHPLC-(ESI)QqQ MS/MS

Abstract

Amygdalin is a cynaogenic diglucoside responsible for the bitterness of almonds. Almonds display three flavor phenotypes, nonbitter, semibitter, and bitter. Herein, the amygdalin content of 20 varieties of nonbitter, semibitter, and bitter almonds from four primary growing regions of California was determined using solid-phase extraction and ultrahigh-pressure liquid chromatography electrospray triple-quadrupole mass spectrometry (UHPLC-(ESI)QqQ MS/MS). The detection limit for this method is ≤ 0.1 ng/mL (3 times the signal-to-noise ratio) and the LOQ is 0.33 ng/mL (10 times the signal-to-noise ratio), allowing for the reliable quantitation of trace levels of amygdalin in nonbitter almonds (0.13 mg/kg almond). Results indicate that amygdalin concentrations for the three flavor phenotypes were significantly different (p < 0.001). The mean concentrations of amygdalin in nonbitter, semibitter, and bitter almonds are 63.13 ± 57.54, 992.24 ± 513.04, and 40060.34 ± 7855.26 mg/kg, respectively. Levels of amygdalin ranged from 2.16 to 157.44 mg/kg in nonbitter, from 523.50 to 1772.75 mg/kg in semibitter, and from 33006.60 to 53998.30 mg/kg in bitter almonds. These results suggest that phenotype classification may be achieved on the basis of amygdalin levels. Growing region had a statistically significant effect on the amygdalin concentration in commercial varieties (p < 0.05).

Investigation of the profile of phenolic compounds in the leaves and stems of Pandiaka heudelotii using gas chromatography coupled with flame ionization detector

“…The amygdalin content of the leaves was higher than that of sweet (nonbitter) almonds, but lower than those of slightly bitter (semi-bitter) almond and apricots (Lee, Zhang, Wood, Castillo, & Mitchell, 2013;Yildirim & Askin, 2010). Amygdalin (D-mandelonitrile-b-D-gentiobioside) has antitussive, lubricant, and antitumor activities (Lv, Ding, & Zheng, 2005;Syrigos, Rowlinson, & Epenetos, 1998 stems also had higher apigenin, catechin, hesperidin, luteolin, kaempferol, and quercetin contents than lettuce, onions, and carrots (Harnly et al, 2006).…”

Ami̇gdali̇n Ve Özelli̇kleri̇

“…Acı badem türlerinin, tatlı badem türlerine göre daha fazla amigdalin içeriğine sahip oldukları tespit edilmiştir [28]. Acı, yarı acı ve tatlı kayısı çeşitleri üzerinde yapılan incelemelerde ortalama amigdalin içeriği sırasıyla 40,06 mg/g, 0,99 mg/g ve 0,06 mg/g olarak saptanmıştır [29]. Conn [30] kayısı çekirdeğinin 9-37 mg/g (20-80 µmol/g), acıbadem çekirdeğinin ise 46 mg/g (100 µmol/g) düzeyinde amigdalin içerdiğini belirtmiştir.…”

“…Prunasin ise prunasin hidrolaz enzimi (EC 3.2.1.21) ile mandelonitril (-hidroksinitril) ve glikoza hidrolize edilir. Son aşamada mandelonitril, β-mandelonitril liyaz [(R)-mandelonitril liyaz veya D--hidroksinitril liyaz] enzimi (EC 4.1.2.10) ile benzaldehit ve hidrojen siyanüre dönüştürülür [4,29].…”

Problems and Pitfalls in the Analysis of Amygdalin and Its Epimer

“…21 However, in most studies, liquid chromatography (LC) seems to have been the method of choice with a C 18 phase, which produces overlapping/shoulder peaks for R-and S-amygdalin. 6 In Figure 2, we show the utility of the preferred stationary phases for amygdalin using simple MS friendly mobile phases in the isocratic mode (MeOH/H 2 O without any additives). A number of achiral and chiral phases such as porous graphitic carbon, vancomycin, teicoplanin, cyclodextrin-bonded silica, and hydroxypropyl-β-cyclodextrin columns were studied.…”

“…Hence, it is important to be able to quantify the amount of its precursor, amygdalin, present in food and supplements. 6 Amygdalin is still sold under various names such as "vitamin B17" and laetrile, although the name laetrile actually is a different compound, Dmandelonitrile-β-D-glucuronic acid ( Figure 1). 7 This work focuses on amygdalin's mandelonitrile stereogenic center.…”