Chemical characterization and antioxidant properties of products and by‐products from Olea europaea L.

Abstract

The products and by‐products of Olea europaea L.: olive fruits (primary agricultural product), oils (primary agro‐industrial product), pomaces (agro‐industrial processing by‐product), and leaves (agricultural practices by‐product), are promising sources of bioactive compounds. In the present study, qualitative and quantitative analyses of selected bioactive components in olive fruits, oils, and pomaces were performed. Total polyphenol content and antioxidant activity were analyzed in all samples (humid pomaces 2015: TPP, 26.0 ± 1.5–43.7 ± 3.0 g(GAEq)/kg DW; TEAC/ABTS, 189.5 ± 3.7–388.1 ± 12.0 mmol(Trx)kg DW). Radical (DPPH) quenching potential was analyzed via photometric and EPR methods, obtaining Vis/EPR signal ratio by 1.05 ± 0.45 and 1.66 ± 0.39 for fruits and pomaces, respectively. Through HPLC‐UV and HPLC‐MS/MS techniques, oleuropein and hydroxytyrosol, as well as selected hydroxycinnamic acids and flavonoids, were identified and quantified in olive fruits and pomaces. The main components were rutin, luteolin, and chlorogenic acid. Cytotoxic assay on fibroblast cells revealed toxic effects for selected extracts at highest tested concentrations (5%).

Determination of Polyphenols Using Liquid Chromatography–Tandem Mass Spectrometry Technique (LC–MS/MS): A Review

“…Consequently, the addition of solvents with higher polarities are necessary to increase the overall polarity of the solvent mixture [ 47 ]. Phenolic acids or highly glycosylated flavonoids require mixtures of organic solvents with water, for example, 75% aqueous acetone [ 48 ], 80% aqueous ethanol [ 36 ], or 80% aqueous methanol [ 49 ].…”

“…To overcome this problem, in recent years, the use of liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) has been increasing in order to characterize the polyphenol-rich extracts. In addition, LC-MS/MS was able to achieve noise reduction and sensitivity improvements by exploiting multiple reaction monitoring (MRM) scan mode [1,28,29,[33][34][35][36][37][38]. Besides, in the last years, high-resolution LC-MS and LC-MS/MS approaches coupled with multivariate statistics have been widely used to realize the so-called "metabolomic profiling" of plant foods for human nutrition.…”

Assessment of Mineral and Phenolic Profiles and Their Association with the Antioxidant, Cytotoxic Effect, and Antimicrobial Potential of Lycium chinense Miller

“…Moreover, previous studies indicated that phenolic compounds have implications in strong cytotoxicity. For instance, higher rutin, quercetin, chlorogenic acid, and luteolin concentrations effectively inhibited the growth of NIH-3T3 cells [55][56][57], whereas quercetin derivatives, such as chloronaphthoquinone quercetin, prevented the proliferation of NIH 3T3 cells [58]. Moreover, we described, in this study, a strong positive correlation between cytotoxicity and protocatechuic acid (r = 0.957, p < 0.01), chlorogenic acid (r = 0.998, p < 0.05), p-coumaric acid (r = 0.984, p < 0.05), or salicylic acid (r = 0.998, p < 0.05), as presented in Table 7, indicating that the higher concentrations of these compounds might be associated with L. The results showed that higher leaf extract concentrations reduced the NIH-3T3 cell number.…”

Chemical Characterisation and Antihypertensive Effects of Locular Gel and Serum of Lycopersicum esculentum L. var. “Camone” Tomato in Spontaneously Hypertensive Rats

“…The advantages of a natural diet can be ascribed to a combination of bioactive compounds [5] or to specific "functional foods". A growing number of scientific papers is continuously being published on this topic [6][7][8][9], together with papers relevant to nutraceutical molecules and delivery systems able to circumvent their common low bioavailability [10,11].…”