Identification and Quantification of Polyphenols in Carob Fruits (Ceratonia siliquaL.) and Derived Products by HPLC-UV-ESI/MSⁿ

Abstract

The polyphenolic patterns of carob pods (Ceratonia siliqua L.) and derived products were identified and quantified using high-performance liquid chromatography-UV absorption-electrospray ion trap mass spectrometry after pressurized liquid extraction and solid-phase extraction. In carob fiber, 41 individual phenolic compounds could be identified. In addition, spectrophotometric quantification using the Folin-Ciocalteu and vanillin assays was performed, and the antioxidative activity was determined as the 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity. Carob pods contain 448 mg/kg extractable polyphenols comprising gallic acid, hydrolyzable and condensed tannins, flavonol-glycosides, and traces of isoflavonoids. Among the products investigated, carob fiber, a carob pod preparation rich in insoluble dietary fiber (total polyphenol content = 4142 mg/kg), shows the highest concentrations in flavonol-glycosides and hydrolyzable tannins, whereas roasted carob products contain the highest levels of gallic acid. The production process seems to have an important influence on the polyphenolic patterns and quantities in carob products.

Medicinal Plants from Jordan in the Treatment of Diabetes: Traditional Uses vs.In VitroandIn VivoEvaluations – Part 2

“…Clinical beneficial effect on improving the glycemic profile without severe adverse effects in type 2 diabetic patients [106] continued next page Flavonoids: mainly myricetin [108]. Phenolics: mainly gallotannins and proanthocyanidins, tannins, flavonol-glycosides, and traces of isoflavonoids [109][110][111][112]. Tannins [113] Significantly decreased the glucose response to and glycemic index of fibers-enriched food in type 2 diabetic subjects.…”

Profiling methods for the determination of phenolic compounds in foods and dietary supplements

“…Compromises in extraction and separation will affect both identification and quantification. Tables 1, 2, 3, 4 present 14 profiling methods for phenolic compounds that have been selected from the literature of the last 15 years [18][19][20][21][22][23][24][25][26][27][28][29][30][31]. This is not meant to be a comprehensive list.…”

“…The selected methods provide a historical perspective and serve as examples of methods that can meet, or can potentially meet, the criteria set forth in the "Introduction." In some cases, the methods were directed at a limited number of food materials, but could be readily modified for application to a greater breadth of materials than originally described [19,20,22,25,27]. In recent years, however, methods have appeared that were designed to cover a wide range of compounds in any type of food material [21,23,24,26,28,29] or as metabolite profiling methods [30,31].…”

“…There are some exceptions, however. Methods are included that use multiple extractions [22], multiple chromatographic runs [28], and tandem MS (MS/MS) [30] or ion trap MS (IT/MS) [27,31] detection. Both of the latter methods are used in conjunction with collision-induced dissociation (CID).…”

“…LC-DAD-MS has been commonly used for profiling methods since the turn of the century [22,23,26,27,30,31]. Cuyckens and Claeys [23] used time-of-flight (TOF) MS (LC-DAD-ESI/TOF/MS) for the fast characterization of flavonoid glycosides and identified 12 flavonoids (three subclasses) in a hawthorn extract.…”