Effect of in vitro gastrointestinal digestion on the composition and bioactivity of anthocyanins in the fruits of cultivated Lycium ruthenicum Murray

Abstract

2019) Effect of invitro gastrointestinal digestion on the composition and bioactivity of anthocyanins in the fruits of cultivated Lycium ruthenicum Murray, ABSTRACT The composition of anthocyanins in cultivated Lycium ruthenicum Murray (CLM) before and after in vitro gastrointestinal digestion was determined using an HPLC system coupled with an electrospray ionization-time of flight mass spectrometry. The antioxidant activity and α-glucosidase inhibition of the anthocyanins before and after digestion were also studied. The results showed that most of the anthocyanins in CLM were found in glycosylated form, containing glycoside ligands. After digestion, the glycosylated anthocyanins were transformed to anthocyanidins (without glycolligands) which exhibited higher antioxidant activity comparatively. Interestingly, although the inhibitory activity of anthocyanins against α-glucosidase was increased by in vitro gastrointestinal digestion, as suggested by IC 50 value, the binding affinity of the anthocyanidins to α-glucosidase remained stable, as demonstrated by fluorescence quenching constant. This suggested that the anthocyanidins might have formed the anthocyanidin-α-glucosidase-substrate tertiary complex. Conclusively, in vitro gastrointestinal digestion may enhance the biological activities of CLM anthocyanins, regarding the antioxidant activity and α-glucosidase inhibition.Efecto de la digestión gastrointestinal in vitro sobre la composición y la bioactividad de las antocianinas en los frutos de Lycium ruthenicum Murray cultivados RESUMEN El presente estudio determinó la composición de las antocianinas en Lycium ruthenicum Murray (CLM) cultivada antes y después de la digestión gastrointestinal in vitro. Para ello se utilizó un sistema de HPLC acoplado con una ionización por electrospray-tiempo de propagación-espectrometría de masas. Asimismo, el estudio analizó la actividad antioxidante y la inhibición de la α-glucosidasa de las antocianinas antes y después de la digestión. Los resultados dan cuenta de que la mayoría de las antocianinas de CLM se encontraron en forma glicosilada y contenían ligandos de glucósidos. Después de la digestión, las antocianinas glicosiladas se transformaron en antocianidinas (sin ligandos de glicol) que, en comparación, mostraron mayor actividad antioxidante. Curiosamente, aunque la actividad inhibitoria de la αglucosidasa por las antocianinas aumentó después de la digestión gastrointestinal in vitro, como lo sugiere el valor de IC 50 , la afinidad de la unión de las antocianidinas a la α-glucosidasa se mantuvo estable, como lo demuestra la constante de desactivación de la fluorescencia. Esto permite suponer que las antocianidinas formaron un complejo terciario de sustrato de antocianidina-α-glucosidasa. Se concluye que la digestión gastrointestinal in vitro puede mejorar las propiedades biológicas de las antocianinas CLM, en relación con la actividad antioxidante y la inhibición de la α-glucosidasa. ARTICLE HISTORY

Antidiabetic Activity of Cactus Acid Fruit Extracts: Simulated Intestinal Conditions of the Inhibitory Effects on α-amylase and α-glucosidase

“…The results of the evaluation of the percentage of inhibition of the four prepared extracts on the activity of α-amylase were significantly different (p < 0.05) and are shown in Table 2. Wang et al [26] reported the same phenomenon in the inhibition of α-amylase in in vitro assay due to the content of anthocyanins of the fruits of cultivated Lycium ruthenicum Murray. WFE extracts had the highest percentage of inhibition of 70% at 25 mg/mL.…”

Fate of Phytometabolites of Antibiotics during In Vitro Digestion and Implications for Human Health

“…For instance, Birk et al reported a rapid degradation of octyl-β- d -glucopyranoside and glycosylated resveratrol to the parent aglycone in an in vitro Rumen Simulation System, within 30 min to 1 h . Conversion of the glycosylated forms of anthocyanins during in vitro gastrointestinal digestion into anthocyanidins has also been reported previously. , These previous results suggest that glycosylated compounds may be converted into parent aglycones during in vitro digestion, due to the acidic pH and/or enzymes present in the digestive fluids. Future work is needed to examine the specific mechanisms of the conversion reactions, as well as identification of any other molecules formed during this process, as all of this information will be critical to informing subsequent human health risk assessment of food crops contaminated with antibiotics.…”

Anthocyanins of Hierbamora (Solanum nigrescens): Revealing their Nutraceutical Potential for Controlling Hypertriglyceridemia and Helicobacter pylori Viability

“…Currently, there are no reports describing the anti‐PL activity of this anthocyanin in scientific literature. However, it has been demonstrated that this compound could be hydrolyzed to produce aglycones by several digestive enzymes, including lipases [19] . This fact may suggest that highly glycosylated substrates such as petunidin‐3‐( cis ‐p‐coumaroyl)‐rutinoside‐5‐glucoside can be hydrolyzed by digestive enzymes.…”

“…However, it has been demonstrated that this compound could be hydrolyzed to produce aglycones by several digestive enzymes, including lipases. [19] This fact may suggest that highly glycosylated substrates such as petunidin-3-(cis-p-coumaroyl)-rutinoside-5glucoside can be hydrolyzed by digestive enzymes. For all anthocyanin assayed, IC 50 values were higher than those obtained for current drugs used as inhibitors of these enzymes (Table 2).…”