Potential of smoke-water and one of its active compounds (karrikinolide, KAR1) on the phytochemical and antioxidant activity of Eucomis autumnalis

CITATION: Aremu, A. O., et al. 2019. Potential of smoke-water and one of its active compounds (karrikinolide, KAR1) on the phytochemical and antioxidant activity of Eucomis autumnalis. Antioxidants, 8(12):611-626, doi:10.3390/antiox8120611The original publication is available at https://www.mdpi.com/journal/antioxidantsEucomis autumnalis (Mill.) Chitt. subspecies autumnalis is a popular African plant that is susceptible to population decline because the bulbs are widely utilized for diverse medicinal purposes. As a result, approaches to ensure the sustainability of the plants are essential. In the current study, the influence of smoke-water (SW) and karrikinolide (KAR1 isolated from SW extract) on the phytochemicals and antioxidant activity of in vitro and greenhouse-acclimatized Eucomis autumnalis subspecies autumnalis were evaluated. Leaf explants were cultured on Murashige and Skoog (MS) media supplemented with SW (1:500, 1:1000 and 1:1500 v/v dilutions) or KAR1 (10−7, 10−8 and 10−9 M) and grown for ten weeks. In vitro regenerants were subsequently acclimatized in the greenhouse for four months. Bioactive phytochemicals in different treatments were analyzed using ultra-high performance liquid chromatography (UHPLC-MS/MS), while antioxidant potential was evaluated using two chemical tests namely: DPPH and the β-carotene model. Smoke-water and KAR1 generally influenced the quantity and types of phytochemicals in in vitro regenerants and acclimatized plants. In addition to eucomic acid, 15 phenolic acids and flavonoids were quantified; however, some were specific to either the in vitro regenerants or greenhouse-acclimatized plants. The majority of the phenolic acids and flavonoids were generally higher in in vitro regenerants than in acclimatized plants. Evidence from the chemical tests indicated an increase in antioxidant activity of SW and KAR1-treated regenerants and acclimatized plants. Overall, these findings unravel the value of SW and KAR1 as potential elicitors for bioactive phytochemicals with therapeutic activity in plants facilitated via in vitro culture systems. In addition, it affords an efficient means to ensure the sustainability of the investigated plant. Nevertheless, further studies focusing on the use of other types of antioxidant test systems (including in vivo model) and the carry-over effect of the application of SW and KAR1 for a longer duration will be pertinent. In addition, the safety of the resultant plant extracts and their pharmacological efficacy in clinical relevance systems is required.National Research Foundationhttps://www.mdpi.com/2076-3921/8/12/611/htmPublisher's versio

The Phenolics and Antioxidant Properties of Black and Purple versus White Eggplant Cultivars

The total phenolic content, anthocyanins, phenolic acids, antioxidant capacity and α-amylase inhibitory activity of black (Aydin Siyahi), purple (Kadife Kemer) and white (Trabzon Kadife) eggplants grown in Turkey were subjected to a comparative investigation. The black cultivar exhibited the highest total phenolic (17,193 and 6552 mg gallic acid equivalent/kg fw), flavonoid (3019 and 1160 quercetin equivalent/kg fw) and anthocyanin (1686 and 6167 g delphinidin-3-O-glucoside equivalent/kg fw) contents in crude extracts of the peel and pulp. The majority of the caffeic acid was identified in the ester (2830 mg/kg fw) and ester-bound (2594 mg/kg fw) forms in the peel of ‘Kadife Kemer’ and in the glycoside form (611.9 mg/kg fw) in ‘Aydin Siyahi’, as well as in the pulp of these two eggplants. ‘Kadife Kemer’ (purple eggplant) contained the majority of the chlorogenic acid in free form (27.55 mg/kg fw), compared to ‘Aydin Siyahi’ in the ester (7.82 mg/kg fw), glycoside (294.1 mg/kg dw) and ester-bound (2.41 mg/kg fw) forms. The eggplant cultivars (peel and pulp, mg/kg fw) exhibited a relatively high delphinidin-3-O-rutinoside concentration in the peel of ‘Aydin Siyahi’ (avg. 1162), followed by ‘Kadife Kemer’ (avg. 336.6), and ‘Trabzon Kadife’ (avg. 215.1). The crude phenolic extracts of the eggplants exhibited the highest antioxidant capacity values (peel and pulp, µmoL Trolox equivalent/kg fw) of 2,2-diphenyl-1-picrylhydrazyl (DPPH, 8156 and 2335) and oxygen radical absorbance capacity (ORAC, 37,887 and 17,648). The overall results indicate that black and purple eggplants are the cultivars with greater potential benefits in terms of their phenolics and antioxidant values than the white eggplant

Changes in the free phenolic acid composition of pepper (Capsicum annuum L.) leaves in response to green peach aphid (Myzus persicae Sulzer) infestation

Aphids are considered one of the most damaging pests in agriculture. Plants respond to aphid attack with the production of toxic, repellent and/or antinutritive metabolites, including phenolic compounds. In this study, we examined the free phenolic acid composition of pepper (Capsicum annuum L.) leaves in response to green peach aphid (Myzus persicae Sulzer) feeding in different time course experiments. When plants were infested with an initial low density of aphids (20 aphids/plant), few significant changes were shown in leave phenolic content suggesting a very slight response from plants. However, with a high density of aphids (200 aphids/plant), several phenolics, especially the cinnamic acids (C6-C3): caffeic acid, p-coumaric acid, and sinapic acid, and also the p-hydroxybenzoic acid, salicylic acid, accumulated at specific times. Conversely, another hydroxy-benzoic acid: protocatechuic acid strongly decreased in response to infestation. The possible role of the observed changes in plant defence responses or in aphid counter-defence is discussed.This work was supported by Ministerio de Economía y Competitividad (Project CGL2016-79054-R), by University of Alicante grant (UAFPU2013-5793) to VFO, by the Czech Science Foundation (No. 19-00973S) and by ERDF project “Development of pre-applied research in nanotechnogy and biotechnology” (No. CZ.02.1.01/0.0/0.0/17_048/0007323). The present work is part of VFO PhD Thesis

Exogenous N-Acetylcysteine alleviates heavy metal stress by promoting phenolic acids to support antioxidant defence systems in wheat roots

Gruz, Jiri/0000-0002-8546-9697WOS: 000475411500007PubMed: 31170649N-acetylcysteine (N-Acetyl L-cysteine, NAC) is a thiol compound derived from the addition of the acetyl group to cysteine amino acid. NAC has been used as an antioxidant, free radical scavenger, and chelating agent for reducing the deleterious effects on plants of biotic and abiotic environmental stresses. It can also relieve heavy metal (HM) toxicity, although its alleviating mechanism remains unknown. In this study, we compared HM-stressed (Cu, Hg, Cd and Pb, 100 mu M each) wheat seedlings without NAC treatment and in combination with NAC (1 mM). In comparison to HMs alone, NAC treatment in combination with HMs (Cu, Cd, Hg and Pb, respectively) stimulated root growth (1.1-, 1.5-, 10.5- and 1.9-fold), and significantly increased fresh (1.3-, 1.5-, 4.3- and 1.4-fold) and dry (1.2-, 1.5-, 2.5- and 1.2-fold) mass. Combination treatment also led to significant reductions in HM concentrations (1.3-, 1.4-, 4- and 1.1-fold, respectively). GSH (1.1 - 1.8-fold), TBARS (1.4 - 2.7-fold) and H2O2 (1.6 - 1.8-fold) contents in treatment with HMs alone were significantly mitigated by the NAC combination. Some of the antioxidant enzyme activities increased or reduced by some HM treatments alone were stimulated by a combination of NAC with HMs, or remained unchanged or changed only insignificantly, supported by the phenolic pool of the plant. Ferulic, p-comaric and syringic acids were the major phenolic acids (PAs) in the roots in free, ester, glycoside and ester-bound forms, and their concentrations were increased by HM treatments alone, in comparison to the control seedlings, while PAs concentrations were relatively reduced by NAC in combination with HMs. These results indicate that NAC can alleviate HM toxicity and improve the growth of HM-stressed wheat seedlings by coordinated induction of the phenolic pool and the antioxidant defence system.Research Fund of Karadeniz Technical University [FBA-2016-5424]; ERDF project "Plants as a tool for sustainable global development" [CZ.02.1.01/0.0/0.0/16_019/0000827]The Research Fund of Karadeniz Technical University (Project No: FBA-2016-5424) provided financial support for this research. The work was supported in part from ERDF project "Plants as a tool for sustainable global development" (No. CZ.02.1.01/0.0/0.0/16_019/0000827)

Comparison of Phenolics and Phenolic Acid Profiles in Conjunction with Oxygen Radical Absorbing Capacity (ORAC) in Berries of Vaccinium arctostaphylos L. and V. myrtillus L.

Caucasian blueberry (Vaccinium arctostaphylos L.) and bilberry (V. myrtillus L.), both native to Turkey, were evaluated for their total phenolics (TP) and anthocyanin (TAC) contents. Individual compositions of free phenolic acids and phenolic acids liberated from ester and glycoside forms were analyzed using UPLC-MS/MS. Berry extracts of each species were separated into three different fractions (sugar/acid, polyphenolic and anthocyanin) by solid phase extraction (SPE). The anthocyanin fractions of each species had the highest level of TP and TAC contents and ORAC values. Each species contained 10 phenolic acids representing each fraction, but in different quantities. The phenolic acids liberated from the esters and glycoside forms were caffeic acid and p-coumaric acid. The fractions containing phenolic acids liberated from ester and glycoside forms had a higher antioxidant capacity than that from free phenolic acids. The data suggest that both berries have potential as good dietary sources of phenolic antioxidants

Comparison of Phenolics and Phenolic Acid Profiles in Conjunction with Oxygen Radical Absorbing Capacity (ORAC) in Berries of Vaccinium arctostaphylos L. and V. myrtillus L.

Strnad, Miroslav/0000-0002-2806-794X; GRUZ, Jiri/0000-0002-8546-9697; Gruz, Jiri/0000-0002-8546-9697WOS: 000375613200003Caucasian blueberry (Vaccinium arctostaphylos L.) and bilberry (V. myrtillus L.), both native to Turkey, were evaluated for their total phenolics (TP) and anthocyanin (TAC) contents. Individual compositions of free phenolic acids and phenolic acids liberated from ester and glycoside forms were analyzed using UPLC-MS/MS. Berry extracts of each species were separated into three different fractions (sugar/acid, polyphenolic and anthocyanin) by solid phase extraction (SPE). The anthocyanin fractions of each species had the highest level of TP and TAC contents and ORAC values. Each species contained 10 phenolic acids representing each fraction, but in different quantities. The phenolic acids liberated from the esters and glycoside forms were caffeic acid and p-coumaric acid. The fractions containing phenolic acids liberated from ester and glycoside forms had a higher antioxidant capacity than that from free phenolic acids. The data suggest that both berries have potential as good dietary sources of phenolic antioxidants.Research Fund of Karadeniz Technical University [2005.111.004.02]; Council of Higher Education of Turkey (CoHE)Ministry of National Education - Turkey; Ministry of Education, Youth and Sports of the Czech Republic through the National Program of Sustainability [LO1204]Financial support for this study was provided by the Research Fund of Karadeniz Technical University (Project No: 2005.111.004.02). The authors Faik Ahmet Ayaz and Huseyin Inceer also greatly appreciate the support from the Council of Higher Education of Turkey (CoHE). This work was also financially supported by the Ministry of Education, Youth and Sports of the Czech Republic through the National Program of Sustainability (grant no. LO1204)

Genetic and phytochemical variability of six Teucrium arduini L. populations and their antioxidant/prooxidant behavior examined by biochemical, macromolecule- and cell-based approaches

Teucrium arduini L., an Ilyric-Balcanic endemic species, has been reported for decades as a valuable plant used in traditional medicine for treating digestive disorders. The present study evaluated genetic and phytochemical variability of six T. arduini populations in order to determine factors that influence an accumulation of polyphenolic compounds. Results strongly suggest that a phytochemical variation was caused by environmental rather than genetic factors. T. arduini leaf extract from the locality Učka which accumulated significantly more polyphenolic phytochemicals in comparison to others showed antioxidant activity in DNA and lipid bioassays. Furthermore, the same extract exhibited prooxidant behavior at protein level and induce formation of reactive oxygen species in human laryngeal carcinoma cells causing cytotoxic activity, in a dose dependent manner. All the results of the present study suggested that T. arduini extract could be responsible for antioxidative/prooxidative mechanisms and would help in determination of optimal conditions for their ethnopharmacological use

Bog bilberry phenolics, antioxidant capacity and nutrient profile

GRUZ, Jiri/0000-0002-8546-9697; Gruz, Jiri/0000-0002-8546-9697; Hermosin-Gutierrez, I./0000-0003-2343-5157; Strnad, Miroslav/0000-0002-2806-794XWOS: 000369494300047PubMed: 26868586Phenolics and nutrient profiles of bog bilberry (Vaccinium uliginosum L.) collected from high mountain pastures in northeast Anatolia (Turkey) were examined for the first time in this study. The major soluble sugar identified in the berry was fructose, following by glucose, and the main organic acid identified was citric acid, followed by malic acid. Eleven phenolic acids and 17 anthocyanin 3-glycosides were identified and quantified. Caffeic acid in the free and glycoside forms and syringic acid in the ester form were the major phenolic acids, and the major individual anthocyanin present in the berry was malvidin 3-glucoside (24%). The highest total phenolics and anthocyanin contents were obtained from the anthocyanin fraction in conjunction with the highest antioxidant capacity, followed by the polyphenolic and aqueous fractions, FRAP, ORAC and DPPH, in that order. Our findings can be used to compare bog bilberry with other Vaccinium berries and to help clarify the relative potential health benefits of different berries. (C) 2016 Elsevier Ltd. All rights reserved.Research Fund of Karadeniz Technical University (KTU-BAP Project)Karadeniz Teknik University [2005.111.004.02]; Council of Higher Education of Turkey (CoHE)Ministry of National Education - Turkey; Ministry of Education, Youth and Sports of the Czech RepublicMinistry of Education, Youth & Sports - Czech Republic [LO1204, LK21306]; Czech Science FoundationGrant Agency of the Czech Republic [GA14-34792S]Financial support for this study was provided by the Research Fund of Karadeniz Technical University (KTU-BAP Project No: 2005.111.004.02). The author Faik Ahmet AYAZ also greatly appreciates the support given by the Council of Higher Education of Turkey (CoHE). J.G. acknowledges the support of the Ministry of Education, Youth and Sports of the Czech Republic (LO1204 and LK21306) and the Czech Science Foundation (GA14-34792S)