Raquel Solana - Academia.edu (original) (raw)

Papers by Raquel Solana

Food Research International

Plants

In this study, in vitro cultures and micropropagated plants of two Mediterranean aromatic plants,... more In this study, in vitro cultures and micropropagated plants of two Mediterranean aromatic plants, Lavandula viridis L’Hér and Thymus lotocephalus López and Morales, were exposed to different temperatures (15, 20, 25, and 30 °C). The effect of temperature on the levels of hydrogen peroxide (H2O2), lipid peroxidation, and osmoprotectants (proline, soluble sugars, and soluble proteins), as well as on the phenolic profile by HPLC-HRMS and intermediates of the secondary metabolism (phenylalanine ammonia lyase (PAL) activity and shikimic acid content), was investigated. Moreover, the antioxidant activity of the plant extracts was also analyzed. Overall, considering the lipid peroxidation and H2O2 content, the extreme temperatures (15 and 30 °C) caused the greatest damage to both species, but the osmoprotectant response was different depending on the species and plant material. In both species, phenolic compounds and related antioxidant activity increased with the rise in temperature in th...

Processes

Phenolic compounds are secondary plant metabolites known to be one of the most important sources ... more Phenolic compounds are secondary plant metabolites known to be one of the most important sources of natural antioxidants in the human diet [...]

Journal of Food Composition and Analysis

Antioxidants

The impact of drought stress induced by polyethylene glycol (PEG) on morphological, physiological... more The impact of drought stress induced by polyethylene glycol (PEG) on morphological, physiological, (bio)chemical, and biological characteristics of Thymus lotocephalus López and Morales shoot cultures have been investigated, as well as the potential of iron oxide nanoparticles, salicylic acid, and methyl jasmonate (MeJA) as alleviating drought stress agents. Results showed that PEG caused oxidative stress in a dose-dependent manner, raising H2O2 levels and reducing shoots’ growth, photosynthetic pigment contents, and phenolic compounds production, especially phenolic acids, including the major compound rosmarinic acid. Moreover, Fourier Transform Infrared Spectra analysis revealed that PEG treatment caused changes in shoots’ composition, enhancing terpenoids biosynthesis. PEG also decreased the biological activities (antioxidant, anti-tyrosinase, and photoprotective) of the eco-friendly extracts obtained with a Natural Deep Eutectic Solvent. MeJA was the most efficient agent in prot...

INCREaSE, 2018

Carob liqueur is a traditional alcoholic beverage manufactured by maceration of plurivarietal car... more Carob liqueur is a traditional alcoholic beverage manufactured by maceration of plurivarietal carobs with plant-based ethyl alcohols. The main purpose of this research was to investigate the influence of the carob variety and different pod processing processes, on the antioxidant capacity (AC) and total phenolic content (TPC) of the final liquor (fruit macerated in 45% v/v of alcohol). For this, pods from three carob varieties characteristic from the Algarve region were tested: Galhosa, Mulata and AIDA. Fig distillate was the fruit-based ethanol used. The maceration time (one or three weeks), the particle size (flour or pieces) and three roasted degrees (unroasted, 120 °C and 150 °C), were the studied processing variables. Ferric Reducing Ability of Plasma (FRAP) and DPPH free radical scavenging methods were used to measure the AC of the liquors and the TPC was determined by the Folin-Ciocalteu method.

Bajo la premisa de disponer de mayor conocimiento sobre los productos amparados bajo las Indicaci... more Bajo la premisa de disponer de mayor conocimiento sobre los productos amparados bajo las Indicaciones Geograficas de los Aguardientes y Licores Tradicionales de Galicia se llevo a cabo esta tesis doctoral, que giro en torno al estudio del aguardiente envejecido y de los aguardientes y licores de hierbas tradicionales. La importancia de los resultados obtenidos expuestos en la parte experimental de la esta tesis radica tambien en el hecho de que el conocimiento de estos productos puede ser extrapolable a cualquier bebida alcoholica similar, elaborada en otras zonas, donde se empleen las mismas materias primas y bajo un mismo proceso de elaboracion. La caracterizacion de licores y aguardientes de hierbas se inicio con un estudio previo de las plantas aromaticas y medicinales (PAM) utilizadas como materias primas en su elaboracion. La caracterizacion de los aceites esenciales/extractos de cada una de las PAM, y que se consideran los responsables de sus propiedades medicinales y aromati...

Molecules, 2021

Nanoparticles (NPs) recently emerged as new chemical elicitors acting as signaling agents affecti... more Nanoparticles (NPs) recently emerged as new chemical elicitors acting as signaling agents affecting several processes in plant metabolism. The aim of this work was to investigate the impact of the addition of copper oxide (CuO), zinc oxide (ZnO) and iron oxide (Fe3O4) NPs (<100 nm) at different concentrations (1, 5 and 10 mg/L) to the culture media on several morphological, physiological and -biochemical parameters of in vitro shoot cultures of Lavandula viridis L’Hér and Thymus lotocephalus G. López and R. Morales (Lamiaceae), as well as on phenolic profile and bioactivity (antioxidant and enzyme inhibition capacities). Although some decreases in shoot number and length were observed in response to NPs, biomass production was not affected or was improved in both species. Most NPs treatments decreased total chlorophyll and carotenoid contents and increased malondialdehyde levels, an indicator of lipid peroxidation, in both species. HPLC-HR-MS analysis led to the identification of...

Plants, 2021

Camellia genus (Theaceae) is comprised of world famous ornamental flowering plants. C. japonica L... more Camellia genus (Theaceae) is comprised of world famous ornamental flowering plants. C. japonica L. and C. sasanqua Thunb are the most cultivated species due to their good adaptation. The commercial interest in this plant linked to its seed oil increased in the last few years due to its health attributes, which significantly depend on different aspects such as species and environmental conditions. Therefore, it is essential to develop fast and reliable methods to distinguish between different varieties and ensure the quality of Camellia seed oils. The present work explores the study of Camellia seed oils by species and location. Two standardized gas chromatography methods were applied and compared with that of data obtained from proton nuclear magnetic resonance spectroscopy (1H-NMR) for fatty acids profiling. The principal component analysis indicated that the proposed 1H-NMR methodology can be quickly and reliably applied to separate specific Camellia species, which could be extend...

Antioxidants, 2021

The present study aimed at evaluating the effectiveness of different natural deep eutectic solven... more The present study aimed at evaluating the effectiveness of different natural deep eutectic solvents (NADES) on the extraction of phenolic compounds from Lavandula pedunculata subsp. lusitanica (Chaytor) Franco, on the antioxidant activity, and acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and tyrosinase (Tyr) inhibitory capacities. Ten different NADES were used in this research and compared with conventional solvents. Ultrasound-assisted extraction (UAE) for 60 min proved to be the best extraction condition, and proline:lactic acid (1:1) and choline chloride:urea (1:2) extracts showed the highest total phenolic contents (56.00 ± 0.77 mgGAE/gdw) and antioxidant activity [64.35 ± 1.74 mgTE/gdw and 72.13 ± 0.97 mgTE/gdw in 2.2-diphenyl-1-picrylhydrazyl (DPPH) and 2.2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) methods, respectively]. These extracts also exhibited enzymes inhibitory capacity particularly against Tyr and AChE. Even so, organic acid-based NADES s...

European Food Research and Technology, 2018

Fig fruits (Ficus carica L.) are used in several Mediterranean countries to produce alcoholic spi... more Fig fruits (Ficus carica L.) are used in several Mediterranean countries to produce alcoholic spirits, with either plurivarietal dried figs or, monovarietal fresh figs as the raw material. To determine the influence of different varietal attributes and production methods on the quality of fig spirits, we analyzed the volatile compounds that contribute to the aroma and organoleptic characteristics of spirits derived from eight Portuguese varieties of fresh figs, as well as mixtures of dried figs processed in the laboratory and plurivarietal fig spirits already in the market. The quantification of major and minor volatiles by GC-FID revealed that the plurivarietal dried fig spirits contained greater quantities of short-chain fatty acid esters and higher alcohols (associated with poor-quality spirits) and compounds with a negative influence on aroma and flavor (such as ethyl lactate, ethyl acetate and diethyl succinate) than the fresh fig spirits. HS-SPME/GC-MS analysis detected 130 volatile compounds, among which the esters ethyl decanoate, ethyl octanoate and ethyl dodecanoate, the aldehydes benzaldehyde and furfural, the monoterpene limonene and the norisoprenoide β-damascenone were common constituents in most of the spirits. The volatile profile of all dried fig distillates was similar and diverse, reflecting the plurivarietal origin, whereas the monovarietal fresh fig spirits produced distinct profiles (sufficient for varietal chemical differentiation), with Burjassote branco distillates containing the greatest number of volatile compounds. This volatile analysis provides a way to determine the quality of fig spirits objectively and to develop spirits with novel characteristics for the market.

Industrial Crops and Products, 2019

Thymus lotocephalus G. Lopez & R. Morales is an aromatic species endemic to the south of Portugal... more Thymus lotocephalus G. Lopez & R. Morales is an aromatic species endemic to the south of Portugal with medicinal properties. The aim of this work was to evaluate the effect of elicitors, cytokinin, and different sucrose concentrations on chemical composition and antioxidant activity of extracts from in vitro regenerated shoots. Elicitors (YE: yeast extract, salicylic acid, and AgNO 3) were added directly to the medium. Phytochemical analysis include evaluation of total phenolic (TPC), flavonoid (TFC), and rosmarinic acid (RAC) contents. The TPCs and TFCs were determined by Folin-Ciocalteu and aluminum chloride colorimetric assays, respectively. Rosmarinic acid (RA), the main compound found in the studied extracts, was quantified by liquid chromatography-photodiode array detector. Results showed that the cytokinin benzyladenine has an inhibitory effect on TPC, TFC and RAC, as well as on antioxidant activity. TPC was only significantly improved by the presence of YE (from 95.49 ± 3.34 to 118.34 ± 6.24 mg GAE /g extract) and TFCs were not affected by elicitation. The increase in sucrose concentration, from 2 to 4%, and the three elicitors tested, particularly YE, enhanced RACs (from 48.61 ± 0.09 in the control medium to 78.57 ± 0.99 mg/g extract in YE-elicited medium). In accordance with these results, the antioxidant activity measured by 2,2-diphenyl-1-picrylhydrazyl, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and ferric reducing antioxidant power assays was significantly greater in extracts from elicited shoots. Overall, the results obtained suggest that shoots of T. lotocephalus are a good source of antioxidant compounds and showed that the production of RA can be promoted by altering in vitro culture conditions.

Journal of the Science of Food and Agriculture, 2019

BACKGROUNDThe production of the traditional carob liquor from Algarve (Portugal) depends on numer... more BACKGROUNDThe production of the traditional carob liquor from Algarve (Portugal) depends on numerous factors such as carob processing, variety and maceration conditions. An experimental design with 36 runs was created to evaluate the effect of the roasting temperature, particle size, variety of carob and time of maceration on several parameters of carob liquors as gallic acid and total phenolic content, the furanic composition (furfural and 5‐(hydroxymethyl)furfural), browning index and in vitro antioxidant capacity.RESULTSThe results revealed that carob variety was the independent variable with the greatest effect on antioxidant capacity, total phenolic and gallic acid content. In particular, AIDA liquors presented the highest results, mainly those prepared with unroasted carob. Meanwhile, Galhosa and Mulata liquors showed the greatest concentrations when the carob pulp was roasted at 150 °C. The furanic composition and browning index were greatly influenced by the carob roasting d...

South African Journal of Botany, 2018

The present work reports investigation on phenolic compounds, antioxidant activity and enzyme inh... more The present work reports investigation on phenolic compounds, antioxidant activity and enzyme inhibitory activities (acetylcholinesterase, butyrylcholinesterase, tyrosinase, α-amylase and α-glucosidase) of different extracts from two Moroccan Asteraceae species; Bubonium imbricatum Cav. and Cladanthus arabicus (L.) Cass. B. imbricatum extracts contained the highest amounts of phenolics and flavonoids, and also exhibited higher antioxidant activity. In this species, the highest total phenolic (1611.13 ± 14.23 μmol GAE /g extract) and flavonoid (376.11 ± 8.22 μmol QE /g extract) contents were observed in aqueous-methanol extract obtained by maceration. Further, UHPLC-MS analysis of C. arabicus and B. imbricatum extracts revealed the presence of several flavonoids (diosmetin, luteolin, apigenin 7-glucoside, and apigenin) and phenolic acids (benzoic, protocatechuic, p-coumaric, gallic, vanillic, caffeic, ferulic and isochlorogenic acids). The antioxidant activity of the extracts was dependent of the extraction process and solvent used. Aqueous-methanol extract of B. imbricatum prepared by maceration showed the highest activity with DPPH, ABTS and FRAP tests (respectively: IC 50 = 8.53 ± 0.38 μg/ml, 3461.8 ± 9.38 μmol TE /g extract and 3281.6 ± 47.43 μmol AAE /g extract). The results indicated that most of the tested extracts or essential oils exhibited activity towards the tested enzymes. Overall, the results obtained in this work indicated the two Moroccan species studied, particularly B. imbricatum, as valuable sources of natural agents beneficial for human health.

Three different techniques: the classical gas chromatography-mass spectrometry (GC-MS) and two "g... more Three different techniques: the classical gas chromatography-mass spectrometry (GC-MS) and two "green" alternative techniques to the classical chromatography, the spectroscopic techniques Fourier transform infrared (FT-IR), and dispersive-Raman were employed to characterize the main chemotypes of different essential oils from plants of the Lamiaceae family and to compare between techniques. Gas chromatography-flame ionization detector (GC-FID) was also employed to quantify the main compounds present in essential oils isolated by hydrodistillation (HD) and semi-quantify essential oil composition isolated by HD and simultaneous steam distillation-solvent extraction (SDE). While GC cannot differentiate between pure and mixed chemotypes of a compound, FT-IR, and Raman methods allow the creation of libraries, through which chemotype determination is feasible even for mixed chemotypes, thus combining robustness with being rapid and non-destructive techniques.

Industrial Crops and Products, 2014

ABSTRACT Fennel (Foeniculum vulgare Miller) is an aromatic plant used, among other applications, ... more ABSTRACT Fennel (Foeniculum vulgare Miller) is an aromatic plant used, among other applications, in the production of traditional herbal liqueurs. In this study, essential oils from fennel were extracted applying two techniques, Soxhlet and accelerated solvent extraction (ASE). The extracts obtained were characterized by GC-MS. Taking into account that estragole is the major constituent of fennel and due to recent studies pointed out its possible carcinogenic properties; this compound was also quantified by GC-FID. The quantification method showed good linearity (r(2) = 0.998) and precision (RSD<5%) with low values of detection (LOD) and quantification (LOQ) limits. A Box-Behnken design was used to correlate three independent variables (temperature, contact time sample-solvent and number of cycles) with the amount of estragole extracted. Meanwhile, the response surface methodology was applied to optimize the extraction of estragole by ASE. The optimal conditions were 125 degrees C, 7 min and 3 cycles. On the other hand, the Soxhlet technique was studied step-by-step. Two variables were optimized: time (4 and 8 h) and solvents, according to their polarity. Methanol and 4 h of extraction showed the best results both qualitatively and quantitatively. The Soxhlet technique provided higher performance of extraction and greater amounts of compounds extracted compared to ASE, but similar concentration of estragole. The shorter time of extraction and the lower amount of solvent used justify the ASE technique choice to characterize fennel essential oils.

Food Control, 2014

Orujo is the name of the Galician (NW of Spain) grape marc distillate. The usual way of Orujo con... more Orujo is the name of the Galician (NW of Spain) grape marc distillate. The usual way of Orujo consumption is as young brandy due to the lack of knowledge about the most appropriate type of barrel for aging and the high cost of the final product. However in the past years, demand for this aged distillate has increased. This manuscript has a double aim: contribute to the analytical characterization of this traditional beverage in terms of mineral constituents and evaluate the influence of the species of wooden barrel in the mineral content. Analyses were performed by flame atomic absorption spectrophotometry (Cu, Mn, Zn, Fe, Ca and Mg), flame atomic emission spectrophotometry (Na and K) and inductively coupled plasma mass spectrometry (Al, Cd and Pb). Orujos aged in Quercus alba showed significant higher value for the majority of metals whereas those aged in Quercus petraea showed the lowest contents. K, Na and Ca were the more abundant minerals in the analyzed distillates. The PCA analysis clearly showed a good separation of samples in terms of mineral constituents. The very low concentrations of all minerals evaluated indicated the good manufactured process and the consumer safety of aged Orujos.

Bioresource Technology, 2012

The enzyme PAD from Lactobacillus plantarum CECT 748 T decarboxylates some cinnamic acids namely ... more The enzyme PAD from Lactobacillus plantarum CECT 748 T decarboxylates some cinnamic acids namely p-coumaric acid (p-CA), caffeic acid (CA), and ferulic acid (FA) into their corresponding 4-vinyl derivatives (4-VD): 4-vinyl phenol (4-VP), 4-vinyl catechol (4-VC), and 4-vinyl guaiacol (4-VG), respectively, which are valuable food additives mainly employed as flavoring agents. The gene encoding this enzyme was cloned and overexpressed in Escherichia coli. Two consecutive experimental designs using these recombinant E. coli cells provided valuable information about the experimental conditions to be used in experiments carried out in 250 ml Erlenmeyer flasks containing synthetic media. In this media, recombinant E. coli cells overproducing L. plantarum PAD showed a preference to degrade mainly p-CA and CA, meanwhile FA was hardly decarboxylated. These cells were also tested on corn cob hydrolysates as they are renewable feedstock for the generation of p-CA and FA. Sterilized liquors obtained after alkaline hydrolysis of corn cob or alkaline hydrolysis of the solid residue coming from acid hydrolysis of corn cob were employed as growth media in fermentations performed in shaker or bioreactor. The fermentative process allowed converting 2222.8 mg/L p-CA into 993.9 mg/L 4-VP (Q 4-VP = 33.128 mg/L•h, Y 4-VP = 0.81 mg/mg). The process described here allowed the production with a high-yield of a valuable food additive from a by-product of the food industry.