Wild strawberry (Arbutus unedo): Phytochemical screening and antioxidant properties of fruits collected in northern Morocco

The aim of this study was to determine the polyphenolic compounds and the antioxidant ability of Arbutus unedo fruits, collected from three regions of northern Morocco, using high-performance liquid chromatography coupled to diode array and electrospray ionization mass spectrometry detection. The proper extraction method has been selected to achieve this objective. After delipidation, the three harvests were extracted by sonication using two solvents with increased polarity ethyl acetate and MeOH:water, 80:20 (v/v). Total polyphenols, flavonoids, tannins and anthocyanins were respectively: 108.41 ± 9.29 mg GAE/g (w/w) dry weight (DW), 101.07 ± 5.6 mg QE/g (w/w) (DW), 0.45 ± 0.48 mg EC/g (w/w) (DW) and 0.35 ± 0.48 mg Pg-3-glu/g (w/w) (DW). EC50 values for reducing power and DPPH radical scavenging activities were between 1.37 ± 0.2 and 17.82 ± 0.12 µg/mL (w/v). A total of 75 compounds were tentatively identified and some of these had never been found until nowadays in Arbutus unedo. The average amount of antioxidant compounds obtained by semi-quantitative analyses was 120.35 ± 32.05 mg/100 g (w/w) (DW). The attained results clearly highlight the potential of A. unedo as a source of healthy compounds, which could be advantageously added to the daily diet, making it a potential candidate for the cure for many emerging diseases

Effect of seasonal variation on the chemical composition and antioxidant and antifungal activities of Convolvulus althaeoides L. leaf extracts

The composition of polyphenols, chlorophylls and carotenoids of eight extracts of Convolvulus althaeoides L. leaves, harvested in two different seasons, winter and spring, and extracted by hot extraction method using four solvents (dichloromethane, chloroform, ethyl acetate and ethanol) with increasing polarity, were evaluated along with their antioxidant and antifungal activities. Qualitative and quantitative variations were observed in the composition based on two different high performance liquid chromatography systems, liquid chromatography-photodiode array detection coupled to either atmospheric pressure chemical ionization mass spectrometry or to electrospray ionization mass spectrometry, permitting the identification of 22 polyphenols, 11 chlorophyll derivatives and 10 carotenoid compounds. Polyphenolic compounds were predominant in extracts from leaves collected in winter, whereas pigments were predominant in the spring collections. Antioxidant activities of the extracts were determined by DPPH radical scavenging method, revealing a half inhibition concentration (IC50) ranging from 0.1369 ± 0.0272 mg g−1 to 0.432 ± 0.0018 mg g−1, with no correlation to seasonal fluctuation. Concerning antifungal assays, ethyl acetate and ethanol extracts have been shown to be the most active against dermatophytes (T. rubrum, T. menthagrophytes, M. canis), with inhibiting percentages reaching 100% with 50 mg mL−1. Moreover, ethyl acetate and ethanol extracts showed a maximum inhibition potential with minimum inhibitory/fungicidal concentrations ranging from 0.78 to 6.25 mg mL−1 on Candida spp. cultures. The winter collect of these extracts showed an inhibitory effect of 90% on Candida albicans germ tubes formation, at a concentration of 3.1 mg mL−1. In conclusion, seasonality seems to influence the quality and the quantity of natural substances from leaves of C. althaeoides L., which have major importance on the antioxidant and the antifungal effectiveness

Profiling the Volatile and Non-Volatile Compounds along with the Antioxidant Properties of Malted Barley

In this work, the stability of antioxidant compounds in malting barley seeds before and after the production of the final products is reported. In this reflection, the findings revealed that the process of fermentation had a significant impact on antioxidant activity. In vitro, antioxidant capacities were evaluated using DPPH free radical scavenging assay. The results obtained from the spectrophotometric analysis showed that the lowest inhibition value was observed in the samples that were obtained by the classical fermentation process (ABC) and the samples of non-alcoholic beer obtained by the thermal process (NABT), with free radical inhibition capacity values of 8.50% and 5.50%, respectively. The samples of hopped wort (HW) and malted barley seeds extract (BSE) showed very high antioxidant activity with free radical inhibition capacity of 14% and 12.60%, respectively. The obtained extracts were analyzed by gas chromatography and high-performance liquid chromatography, both combined with mass spectrometry detection (GC-MS, HPLC-MS). GC-MS analysis of the SPME extraction showed the presence of 29 compounds with isopentyl alcohol in major concentration (18.19%) in the alcoholic beer; on the other hand, the HPLC-DAD-ESI/MS analysis of the ethyl acetate extract showed the presence of 13 phenolic compounds. Interestingly, the degradation of 3-Hydroxyphloretin 2'-O-glucoside in the final products of the non-alcoholic beers was found. Finally, the FTIR analysis was also employed in order to detect the type of efficient groups present in the extracts

Elucidation of Antioxidant Compounds in Moroccan Chamaerops humilis L. Fruits by GC-MS and HPLC-MS Techniques

The aim of this study was to characterize the phytochemical content as well as the antioxidant ability of the Moroccan species Chamaerops humilis L. Besides crude ethanolic extract, two extracts obtained by sonication using two solvents with increased polarity, namely ethyl acetate (EtOAc) and methanol-water (MeOH-H2O) 80:20 (v/v), were investigated by both spectroscopy and chromatography methods. Between the two extracts, the MeOH-H2O one showed the highest total polyphenolic content equal to 32.7 +/- 0.1 mg GAE/g DM with respect to the EtOAc extract (3.6 +/- 0.5 mg GAE/g DM). Concerning the antioxidant activity of the two extracts, the EtOAc one yielded the highest value (1.9 +/- 0.1 mg/mL) with respect to MeOH-H2O (0.4 +/- 0.1 mg/mL). The C. humilis n-hexane fraction, analyzed by GC-MS, exhibited 69 compounds belonging to different chemical classes, with n-Hexadecanoic acid as a major compound (21.75%), whereas the polyphenolic profile, elucidated by HPLC-PDA/MS, led to the identification of a total of sixteen and thirteen different compounds in both EtOAc (major component: ferulic acid: 104.7 +/- 2.52 mu g/g) and MeOH-H2O extracts (major component: chlorogenic acid: 45.4 +/- 1.59 mu g/g), respectively. The attained results clearly highlight the potential of C. humilis as an important source of bioactive components, making it a valuable candidate to be advantageously added to the daily diet. Furthermore, this study provides the scientific basis for the exploitation of the Doum in the food, pharmaceutical and nutraceutical industries

Phytochemical Profile and Antioxidant Activity of the Aerial Part Extracts from Matthiola incana subsp. rupestris and subsp. pulchella (Brassicaceae) Endemic to Sicily

As part of a project aimed at investigating the Matthiola taxa endemic to Sicily (Italy), this study focused on Matthiola incana, an edible species used in the traditional medicine of various countries. Herein, the characterization of phenolic and volatile compounds, the antioxidant capacity in vitro (1,1-diphenyl-2-picrylhydrazil (DPPH), reducing power and Fe2+ chelating activity assays) and the toxicity test (Artemia salina lethality bioassay) of the hydroalcoholic extracts from the aerial parts of M. incana subsp. rupestris from Mt. Pellegrino (Palermo) and Mt. Erice (Trapani), and of M. incana subsp. pulchella are reported. The results are compared with those previously shown for M. incana subsp. incana, to achieve a comprehensive overview of the three subspecies. The HPLC-PDA/ESI-MS and SPME-GC/MS analyses led to the identification of 13 phenolics and 54 volatile compounds. Differences in the qualitative-quantitative profile of these phytochemicals have been highlighted between the M. incana subspecies. The antioxidant tests showed different activity for the extracts, which were found to possess better chelating properties. At last, none of the tested extracts displayed toxicity against brine shrimp larvae. These findings enrich the knowledge on the Matthiola taxa growing wild in Sicily, both from the strictly systematic point of view and for the possible applications as sources bioactive compounds that can be used in the nutraceutical field

The Digestibility of Hibiscus sabdariffa L. Polyphenols Using an In Vitro Human Digestion Model and Evaluation of Their Antimicrobial Activity

Hibiscus sabdariffa L. (H.s.) is a polyphenolic-rich plant commonly consumed either as a beverage or spice. The aim of the present study was to evaluate the in vitro digestibility of H.s. polyphenols using an in vitro model of digestion which simulates the human stomach and small intestine. The bioaccessible polyphenols released in the digested samples were analyzed by liquid chromatography coupled to photodiode array and mass spectrometry detection. H.s. anthocyanins (cyanidin-3-O-sambubioside and delphinidin-3-O-sambubioside) content drastically dropped during the digestion process from 2.91 ± 0.03 µg g−1 and 8.53 ± 0.08 µg g−1 (w/w) CG (Cyanidin-glucoside) in the raw extract, respectively, to 0.12 ± 0.01 µg g−1 0.12 ± 0.01 µg g−1 (w/w) CG at the end of duodenal digestion. Total polyphenols also have shown a decrease from 1192.65 ± 30.37 µg g−1 (w/w) in the raw extract to 282.24 ± 7.21 µg g−1 (w/w) by the end of gastric digestion, in contrast to their increase by the end of duodenal digestion 372.91 ± 3.97 µg g−1 (w/w). On the other hand, the decrease in certain compounds (e.g., caffeoylquinicandcoumaroylquinic acids) was observed during gastric digestion resulting in an increase of quinic acid in the duodenal aliquots, thus suggesting that this compound was derived from the degradation of the more complex hydroxycinnamic acids. H.s. extract also exhibited a bacteriostatic effect against Staphylococcus aureus ATCC 6538 (MIC of 2.5 mg mL−1) and a bactericidal effect against a food isolate of Listeria monocytogenes (MBC of 2.5 mg mL−1). The undigested polyphenols of H.s. in the upper gastrointestinal tract enters the colon, where they are metabolized by the gut microbiota. The present study results showed that resistance of H.s. polyphenols during gastrointestinal digestion might affect their uptake, resulting in a decrease in their digestibility

HPLC-PDA/ESI-MS Analysis of Phenolic Compounds and Bioactivities of the Ethanolic Extract from Flowers of Moroccan <i>Anacyclus clavatus</i>

In this work, polyphenols were extracted from Anacylus clavatus flowers using a hydroethanolic solvent, and the obtained extract was studied for its total phenol and flavonoid contents and evaluated for its antioxidant and antibacterial capacities. The contents of total phenols and flavonoids were measured by employing gallic acid and quercetin as references, respectively, and the phenolic composition analysis was conducted using high-performance liquid chromatography combined with a photodiode array and electrospray ionization mass spectrometry (HPLC-PDA/ESI-MS). The antioxidant capacity of the extracts was tested using a potassium ferric reducing antioxidant power (PFRAP) assay, and the antibacterial activity assay was carried out against Gram-negative bacteria (Escherichia coli and Salmonella typhimirium) and Gram-positive bacteria (Staphyloccocus aureus and Listeria monocytogenes) using the broth microdilution assay. The phenolic and flavonoid contents of the extracts equaled 9.53 ± 0.48 mg GAE/g dm and 1.31 ± 0.06 mg QE/g dm, respectively. The chromatographic analysis of the phenolic profile detected 26 phenolic compounds belonging to phenolic acids, flavones and flavonols, and with the caffeoylquinic acid derivatives being the major phenolic compounds present in 12 isomers. Only one organic compound, viz. citric acid, was found. The extracts exhibited interesting antioxidant activity. Bacteriostatic activity towards Escherichia coli and bactericidal activity against Salmonella typhimirium, Staphyloccocus aureus and Listeria monocytogenes were determined. This study revealed that Anacyclus clavatus flower extracts contain phenolic compounds with interesting bioactivities

Determination of the Phenolic Profile, and Evaluation of Biological Activities of Hydroethanolic Extract from Aerial Parts of Origanum compactum from Morocco

Origanum compactum belonging to the family Lamiaceae is widely used in food and pharmaceutical fields due to its biologically active substances. We aimed to investigate the total phenol and flavonoid contents and the phenolic composition, and to evaluate the antioxidant and antibacterial properties of hydroethanolic extract from of Origanum compactum. Total phenol and flavonoid contents were evaluated using gallic acid and quercetin as standards, respectively, and the phenolic profile was characterized using high-performance liquid chromatography coupled to a photodiode array and electrospray ionization mass spectrometry (HPLC-PDA-ESI/MS). The antioxidant activity was determined by two methods: ferric reducing power (FRAP) assay and the phosphomolybdate method. The antibacterial effect was evaluated against four bacteria (Escherichia coli, Salmonella typhimurium, Staphylococcus aureus and Listeria monocytogenes) using the broth microdilution method. The findings show that the total phenolic and flavonoid contents were 107.789 &plusmn; 5.39 mg GAE/g dm and 14,977 &plusmn; 0.79 mg QE/g dm, respectively. A total of sixteen phenolic compounds belonging to phenolic acids and flavonoids were detected. Furthermore, the extract showed strong antioxidant activity, and displayed a bacteriostatic effect against Escherichia coli and Salmonella typhimuriumn, and a bactericidal effect against Staphylococcus aureus and Listeria monocytogenes. Therefore, this study reveals that Origanum compactum extracts display potential as antibacterial and natural antioxidant agents for fighting against pathogenic bacteria and preventing oxidative stress

Phenolic Composition, Antioxidant and Antibacterial Activities of Extract from Flowers of <i>Rosa damascena</i> from Morocco

Rosa damascena is referred to as the queen of roses due to its ornamental, flavoring, and perfuming uses, along with its recognized use in therapy. This study aimed to investigate the total phenols and flavonoids contents, the phenolic compounds, and study the antioxidant and antibacterial properties of the hydroethanolic extract from Rosa damascena flowers, collected from the Middle Atlas of Morocco (Khenifra). The total phenols and flavonoids were assessed using gallic acid and quercetin as standards, and the phenolic compounds were characterized using HPLC-PDA-ESI/MS. The antioxidant activity was evaluated by two methods, namely ferric reducing assay power and total antioxidant capacity. The broth microdilution method was employed to evaluate the antibacterial activity of extract against four bacteria (Escherichia coli, Salmonella typhimurium, Staphylococcus aureus, and Listeria monocytogenes). Up to 16 phenolic compounds belonging to tannins and flavonoids were positively identified in the Rosa damascena extract. The latter displayed high antioxidant activity and exhibited a bacteriostatic effect against Escherichia coli and a bactericidal effect against Salmonella typhimuriumn, Staphylococcus aureus, and Listeria monocytogenes. As a result, the flowers of Rosa damascena might be employed as natural agents in the pharmaceutical field

Comprehensive Evaluation on the Use of Thymus vulgaris Essential Oil as Natural Additive against Different Serotypes of Salmonella enterica

Essential oils were proposed as natural additives to ensure food safety and quality in a more sustainable approach. The chemical composition of Thymus vulgaris essential oil (TV-EO) collected from Morocco, its antioxidant and antimicrobial activity against different serotypes of Salmonella enterica subsp. enterica was investigated. A mathematical model was implemented to predict the Salmonella behavior when exposed to TV-EO. In situ antimicrobial activity and sensory influence were tested in minced poultry meat experimentally contaminated with Salmonella and treated with TV-EO. Hydrodistillation was used to extract TV-EO, and gas chromatography-mass spectrometry (GC-MS) analysis found thymol as the most representative compound. Results of the antioxidant activity showed an IC50 of 0.29 ± 0.04 mg/mL, EC50 of 0.74 ± 0.08 mg/mL, and RC50 of 0.59 ± 0.06 mg/mL. All the Salmonella strains were susceptible to TV-EO with performing results for the disc diffusion method (inhibition diameters ranged between 24 ± 0.4 mm and 32 ± 0.6 mm), determination of minimum inhibitory concentration (MIC; 0.5%) and minimum bactericidal concentration (MBC; 1%), sublethal-injured cells (7.99 ± 0.08%), in situ activity (growth inhibition after 3 days), and meat sensory preservation (up to 1 week). The implemented mathematical model well fitted the Salmonella growth curve. TV-EO with significant antioxidant and antibacterial activities was suitable to ensure food safety and quality consistent with the new sustainable trends in the food field