Hydrophilic Antioxidant Activity Research Articles

Carvacrol maintains antioxidant capacity in goji fruit by increasing the content of bioactive compounds

Fresh goji berries are prone to decay and spoilage, resulting in economic losses. We investigated the effects of carvacrol (CVR) on the natural disease incidence and quality of goji berries by fumigating with varying CVR concentrations (0.06, 0.12, and 0.24 μL/mL). The results showed that CVR treatment inhibited the natural decay of goji berries by enhancing their quality, color, and total soluble solids/titratable acidity ratio. Moreover, 0.12 μL/mL CVR was determined to be the optimal concentration, as it maintained the sensory quality (except for aroma) and inhibited the disease incidence and preliminary disease expansion of goji fruit inoculated with Alternaria alternata. The treated berries exhibited elevated total phenolic content, total flavonoid content, ascorbic acid, glutathione, melatonin, total chlorophyll, and carotenoid levels. Higher hydrophilic and lipophilic total antioxidant activities and free radical scavenging capacities were also observed in the treated berries. Targeted metabolomics showed that treatment with 0.12 μL/mL CVR increased the levels of four phenolic acids (caffeic acid, chlorogenic acid, ferulic acid, and protocatechuic acid) and two flavonoids (naringenin and quercetin) in goji berries, thereby activating the gene expression of the phenylpropanoid metabolic pathway. In summary, CVR treatment delayed fruit senescence and the decline in fruit quality, promoted the accumulation of bioactive compounds, and improved antioxidant capacity and disease resistance by activating the phenylpropanoid metabolic pathway.

Assessment of Yield and Quality of Eggplant (Solanum melongena L.) Fruits Improved by Biodegradable Mulching Film in Two Different Regions of Southern Italy

Low-density polyethylene (LDPE) mulching films have an important function in crop cultivation; at the end of their life, however, their removal and disposal become both an economic and environmental problem. One possible alternative to low-density polyethylene (LDPE) mulch is provided by certified soil-biodegradable mulch films, such as those produced by Novamont and commercially available under the trade name MaterBi®. MaterBi is a biodegradable thermoplastic material made with starch and a biodegradable copolyester based on proprietary technology. In this study, we compared two biodegradable MaterBi®-based films (commercial and experimental films) with bare soil and a low-density polyethylene to evaluate their effect on yield and on a number of qualitative characteristics (organoleptic and nutraceutical composition) of eggplant fruits (cv Mirabelle F1) grown in two different regions in Southern Italy (Sicily and Campania). In our study, the use of biodegradable MaterBi® films improved not only yield and production parameters, such as the number and average weight of fruits, but also lipophilic and hydrophilic antioxidant activity and phenolic and ascorbic acid content. For many parameters, responses differed according to the cultivation environment and, in particular, the site’s pedoclimatic conditions. Our results suggest that biodegradable MaterBi®-based mulching films are a potentially valid alternative to traditional LDPEs, providing the production and quality benefits reported above and promoting environmental sustainability, thanks to their positive biodegradable properties.

Assessment of bioactive compounds, antioxidant potential, and enzymatic activity in different guava (Psidium guajava) cultivars

AbstractFresh fruits of five guava (Psidium guajava L.) cultivars were assessed for ascorbic acid (AA) content and enzymatic antioxidants (superoxide dismutase [SOD] and ascorbate peroxidase [APX]) activities, while extracted peel and pulp samples were analyzed for total phenol (TP) and total flavonoids (TFs). The hydrophilic and lipophilic antioxidant activity was evaluated using six different analytical assays. We noticed significant differences in the antioxidant compounds (AA, TP, and TF). SOD and APX activities varied from ∼54 to 71 and ∼41 to 59 U/g FW, respectively. Cv. KG Guava had the highest TP (in both hydrophilic and lipophilic peel and pulp fractions) and TF (in hydrophilic pulp and lipophilic peel and pulp fractions). Therefore, the strongest antioxidant potential was exhibited by KG Guava using most of the assays, which was followed by the cultivars Kimchu and Salithong. The results provide valuable information about antioxidant potential of guava peel and pulp fractions, which is essential for their future application in the food and health industry.

Phytochemical Profile and Antioxidant Activity of Some Open-Field Ancient-Tomato (Solanum lycopersicum L.) Genotypes and Promising Breeding Lines

Tomato landraces have progressively faded into obscurity, making way for new hybrids and elite tomato cultivars. This study presents a comprehensive evaluation of the agronomic attributes, physicochemical properties, and functional traits across seven cultivars, comprising two high-pigment varieties, ‘HLT−F81’ and ‘HLT−F82’, as well as five underutilized ancient-tomato genotypes considered as landraces. Most of the studied genotypes exhibited satisfactory horticultural and processing traits. The average fruit weight ranged from 73.3 g in ‘Rimone’ to 91.83 g in ‘HLT−F81’, while the soluble solids content ranged from 4.66 °Brix in ‘Justar’ to 6.08 °Brix in ‘HLT−F81’. The functional quality and the content of most antioxidants, as well as the antioxidant activity in both hydrophilic and lipophilic fractions, proved to be the most discriminating parameters among the tomato genotypes. The content of β−carotene and lycopene spanned from 2.94 mg kg−1 fw in ‘Rio Grande’ to 13.94 mg kg−1 fw in ‘HLT−F82’ and 227.8 mg kg−1 fw in ‘HLT−F81’, yielding large variations compared to ‘Rio Grande’. The total phenolic content ranged from 139.83 mg GAE kg−1 fw in ‘Rimone’ to 352.41 mg GAE kg−1 fw in ‘HLT-F81’, while the flavonoid content varied from 136.16 mg RE kg−1 fw in ‘Justar’ to 311.23 mg RE kg−1 fw in ‘HLT-F82’. The presence of tocopherol isomers was genotype-dependent, with a higher content in lines carrying the high-pigment mutations. Among the tested tomato genotypes, the high-pigment tomato line ‘HLT−F81’ achieved the highest hydrophilic and lipophilic antioxidant activity values. This study primarily focused on the recovery and valorization of tomato genetic resources and landraces. It also aimed to identify desirable horticultural (yield, low-input, and low-water demand), processing (°Brix and titratable acidity), and quality (rich antioxidant berries) traits for introgression into new tomato cultivars better suited to the evolving climate conditions of the near future.

Photosynthesis, Yield and Quality in Wild Rocket (Diplotaxis tenuifolia L.) under Photoluminescent Greenhouse Covers

Manipulation of light spectral composition is a useful tool to drive morphological, physiological and metabolic responses in several crops, ultimately improving yield and quality. Novel materials for greenhouse covering are being developed in order to make a better use of the available sunlight: among these are the cover films or panels incorporating fluorescent additives which are able to convert UV solar radiation into visible light. In this research, we compared the physiological traits and the agronomical performance of wild rocket grown in pots in the winter–spring season, under four different greenhouse prototypes covered with poly-methyl-methacrylate (PMMA)-based panels. PMMA panels doped at 3% (Dop3) or 7% (Dop7) w/w with a blend of rare-earth elements (partially converting the solar UV radiation to red and blue wavelengths) were compared with an undoped (UD) and a whitewashed (WW) PMMA greenhouse. The rocket yield was higher in Dop3 (+30%), while it was unaffected in Dop7 and lower in WW (−39%), compared to the control (6.06 kg m−2). The leaf greenness decreased while both the ABTS and the hydrophilic antioxidant activities increased under the doped and the whitewashed greenhouses. The Dop3 treatment provided the best results in terms of yield and quality of greenhouse wild rocket in winter–spring cycle. However, the analysis of OJIP kinetics of chlorophyll fluorescence revealed that the main factor affecting the photosynthetic performance was the light intensity inside each greenhouse rather than the modulation of light spectrum, because of the different shading properties of the doping and whitewashing treatments. Although these results did not allow us to distinguish between the combined effects of shading and light spectrum modulation, the use of photoluminescent covers can be foreseen as a promising innovation in greenhouse horticulture.

Determination of healthy natural antioxidants in selected muskmelon (Cucumis melo) cultivars

Muskmelon (Cucumis melo L.) is a popular summer fruit consumed all over the world due to the combination ofrefreshingly sweet taste, pleasant flavour and nutritional value. Melon fruit is characterized by germplasm variabilitywith superior quality. This study aimed to evaluate 5 promising local muskmelon cultivars (Maazoun, Galaoui,Stambouli, Trabelsi, Asli) for some physicochemical characteristics, the content of different bioactive compoundsand the antioxidant activity. The experiments were conducted for two consecutive years 2018 and 2019 at the support station of the inter-professional vegetable group positioned in the North East of Tunisia. Significant differences were observed across the melon cultivars (P<0.05) for soluble solids (9–12°Brix), pH (5.5–6.6), carotenoid (7.5–59.5 mg/ kg FW), phenolic (400–1390 mg GAE/kg FW), flavonoid (251.3–390 mg RE/kg FW), vitamin C (138.2–193 mg/kg FW) contents, as well as hydrophilic (102.28–285.43 μM Trolox/100 g FW) and lipophilic (30–180.22 μM Trolox/100 g FW) antioxidant activities. Galaoui showed the highest levels of carotenoids, phenolics, flavonoids, vitamin C and antioxidant activities followed by Stambouli. Trabelsi cultivar also had a high level of flavonoids. The enhanced hydrophilic antioxidant activity in Galaoui was significantly correlated to phenolic content (r = 0.91). These findings proved that besides being refreshing summer fruit, muskmelon can be considered a promising healthy produce with a superior potential source of natural antioxidants.

Yield and Quality of Processing Tomato as Improved by Biostimulants Based on Trichoderma sp. and Ascophyllum nodosum and Biodegradable Mulching Films

Tomato is a great source of bioactive compounds, is important for human health, and is cultivated worldwide. However, the high inputs required for its cultivation must be sustainably managed in order to limit yield losses, thus obtaining high-quality and environmentally friendly production. In this perspective, we compared four biostimulant treatments, i.e., Ascophyllum nodosum extract—Bio; microbial biostimulant containing the micro-organism Trichoderma afroharzianum—Mic; a combination of both—M-B; not treated—Control) and three mulch treatments (biodegradable film Ecovio—ECO; biodegradable film MaterBi®—NOV; bare soil—BS) and evaluated their effects on yield and quality traits in processing tomato. Both biodegradable films elicited a 27.0% yield increase compared to plants grown on bare soil, and biostimulants determined a 23.7% increase over the Control, with the best performance recorded for M-B (+24.8%). Biodegradable MaterBi® film (NOV) was associated with higher total soluble solids (TSS) and firmness values (average of 4.9 °Brix and 1.30 kg cm−2, respectively), even if a significant effect of biostimulants was observed only for the second element. Carotenoid content was higher in non-treated plants grown on bare soil as well as hydrophilic antioxidant activity (AA), but in this case, no differences between biostimulant treatments were recorded. The lipophilic AA in NOV-treated plants was about six and four times higher than observed in BS and ECO treatments, respectively; NOV also caused a 38.7% increase in ascorbic acid content over the Control but was not different from ECO. All biostimulant treatments elicited a 30% increase in phenol content compared to Control plants. Our findings highlight that microbial biostimulants based on A. nodosum extract and T. afroharzianum (both applied singularly and combined) can be considered a sustainable tool for increasing yield and improve some quality traits of processing tomato; in addition, we also confirmed the capability of biodegradable mulches, in particular, MaterBi®, to enhance the agronomic performance of tomato.

Nutrient and Nutraceutical Quality of Rocket as a Function of Greenhouse Cover Film, Nitrogen Dose and Biostimulant Application

The nutrient and nutraceutical quality of greenhouse wild rocket is strongly influenced by the light environment and nitrogen fertilization. We investigated the effects of two cover materials, a diffuse light film (Film1) and a traditional clear film (Film2), and three nitrogen regimes, no N supply (N0) and sub-optimal (N1) and optimal (N2) doses, also in combination with a biostimulant (Stimolo Mo), on the mineral composition, antioxidant properties and chlorophyll and carotenoid content of rocket plants grown in the autumn–spring cycle. The leaf concentration of most of the minerals was higher under Film1 compared to Film2. In general, K, Ca, Mg and Na were higher, and S was lower in the presence of N supply, and the addition of the biostimulant promoted the mineral uptake. Under Film1, the hydrophilic antioxidant activity (HAA) was higher in some harvests, and the ABTS antioxidant activity (ABTS AA) in the first one, while always lower afterward, than under Film2. Nitrogen fertilization did not affect the antioxidant activity, while it reduced the content of total phenols and ascorbic acid. The biostimulant application increased ABTS AA at the optimal N dose and reduced total phenols in unfertilized plants. Both the diffuse light and the N supply inhibited the synthesis of ascorbic acid, while N fertilization and the biostimulant promoted the synthesis of chlorophylls. The experimental treatments exerted variable effects over time and significant interactions with the harvest period were found for many of the investigated parameters.

ABTS/TAC Methodology: Main Milestones and Recent Applications

ABTS (2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic) acid) is a widely used compound for determining the total antioxidant capacity (TAC) of plant extracts, food, clinical fluids, etc. This photometric assay is based on the reduction by the presence of antioxidant compounds of a well-known metastable radical (ABTS•+) which can be formed via several different approaches and be used in many different determination methodologies such as automated photometric measures in microplates, clinical robots, valuable titrations, and previous liquid chromatographic separation. Another interesting aspect is that, in some cases, the ABTS/TAC method permits sequential hydrophilic and lipophilic antioxidant activity determinations, obtaining total antioxidant activity values through the summatory data of both types of antioxidants. In this work, we present a review of several aspects of the ABTS/TAC, highlighting the major achievements that have made this method so widely used, e.g., ABTS radical formation in hydrophilic or lipophilic reaction media, measurement strategies, automatization, and adaptation to high-throughput systems, as well as the pros and cons. Moreover, some recent examples of ABTS/TAC method applications in plant, human, and animal samples are discussed.

The Changes of Antioxidant Contents and Antioxidant Activities of the Tomato Cultivar Fentailang during the Maturity Stages.

The aim of this study was to analyze the contents of ascorbic acid, phenolics, flavonoids, carotenoids, lycopene, β-carotene and their antioxidant activities in the different maturity stages of tomatoes. The results showed that tomatoes in pink and red stages exhibited higher contents of ascorbic acid concomitant with the correspondent higher hydrophilic antioxidant activities. The contents of phenolics, carotenoids and lycopene were increasing till the red maturity stage. Significant correlation between the DPPH radical scavenging activity and carotenoids, however lycopene was effective in its lowest concentration. The β-carotene was intensively synthesized between the green and breaker maturity stages, and higher correlated with the FRAP capacity. These findings indicated that tomatoes can be considered as natural sources of bioactive compounds regardless of the maturity stages, while tomatoes in pink and red maturity stages has higher nutritional value and antioxidant activity.

Effect of Biostimulant Application on Plant Growth, Chlorophylls and Hydrophilic Antioxidant Activity of Spinach (Spinacia oleracea L.) Grown under Saline Stress

Irrigated agricultural lands are prone to salinity problems which may imperil horticultural crops by reducing growth, yield and even qualitative traits. Eco-friendly approaches such as biostimulant application and in particular protein hydrolysates from vegetal origin are implemented to mitigate salinity stress effects on crops. For this reason, a greenhouse experiment on spinach irrigated with increasing concentrations of saline water (EC = 3 dS m−1 (EC3), 6 dS m−1 (EC6) and 9 dS m−1 (EC9), in addition to non-saline treatment (EC0)) was organized, while plants were subjected to foliar applications of a protein hydrolysate from vegetal origin on a weekly basis. The application of this biostimulant helped mitigate the adverse effects of saline stress, by increasing the SPAD index and total chlorophylls of spinach plants. Yield was significantly boosted under biostimulant treatment in saline conditions and reached the value obtained in control treatment (no biostimulants added) × EC0 in the case of EC 3 and 6 dS m−1. In addition, the number of leaves and plants m−1 was increased under biostimulant treatment, and most importantly the hydrophilic antioxidant activity of spinach, thus a qualitative aspect of great importance was also increased. Such results increase the knowledge on the effects of protein hydrolysates application on an important leafy vegetable and may help growers mitigate saline conditions and maintain high crop yield and high quality of the final product when no other source of irrigation water is available.

Effect of Prolonged Cold Storage on the Dynamics of the Enzymatic and Non-Enzymatic Antioxidant System in the Mesocarp of Avocado (Persea americana) cv. Hass: Relationship with Oxidative Processes

This work evaluated the enzymatic and non-enzymatic antioxidant defense systems of avocados cv. Hass stored at 7 ± 0.5 °C for 10, 20, and 30 d, and at the stage of edible ripeness. The enzymatic antioxidant enzyme system included superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), and the non-enzymatic antioxidant system was composed of total phenolic compounds (TPC), total carotenoids (TC), α-, β-, and γ-tocopherols, as well as hydrophilic (H-AOX) and lipophilic (L-AOX) antioxidant activities. In addition, polyphenol oxidase (PPO) and lipoxygenase (LOX) activities, TBARS values and pulp browning area were determined. At edible ripeness, low SOD and POD but higher CAT activities were evidenced in response to their joint participation in the oxidative stress developed. In addition, low content of γ-tocopherol and higher contents of TPC and TC were evidenced and suggest their individual or joint participation in defense against oxidation. The other compounds and activities evaluated tended to remain constant. Oxidative damage was evidenced by the increase in PPO activity and TBARS values, while LOX did not play a significant role. Pulp browning area did not surpass 6% in affected fruit. The results indicate that under these conditions oxidative stress was largely restrained by the endogenous fruit antioxidant defense system.

Influence of Bunch Compactness and Berry Thinning Methods on Wine Grape Quality and Sensory Attributes of Wine in Vitis vinifera L. cv. ‘Monastrell’

Presently, there is no information available about the effect of bunch compactness and berry thinning methods on wine grape quality and sensory attributes of wine in the ‘Monastrell’ cultivar. Thus, the main aim of the present study was to determine the influence of bunch compactness and two berry thinning methods, which consisted of the reduction of 25% and 50% of the number of berries in each bunch, on wine grape quality and organoleptic quality of wine in this cultivar. Non-compact bunches and both berry thinning methods showed a significant reduction in total yield, bunch compactness, and bunch fresh mass compared with compact and control ones, respectively. However, these methods, especially the 50% one, significantly increased the content of total soluble solids and total phenolics. Furthermore, both berry thinning methods promoted the increase in total anthocyanins concentration in berries, as well as the hydrophilic total antioxidant activity. Berry thinning methods led to wines with greater sensory descriptors, such as fruity (odor and flavor), sour, sweet, aftertaste, and color, and were preferred by consumers. Finally, 50% berry thinning is the most useful tool to decrease bunch compactness and improve the overall quality of berries and sensory attributes of wines.

Antioxidant Properties of Algae in the U.S. Virgin Islands

Compounds high in antioxidant activity counteract the formation of free radicals, which are linked to many human diseases and cancers. The objectives of this study were to quantify the hydrophilic antioxidant activity (HAA), lipophilic antioxidant activity (LAA), and the total antioxidant activity (TAA) of algae collected in the US Virgin Islands. The three algae divisions collected are Rhodophyta, Chlorophyta, and Phaeophyta. We hypothesize that the HAA will be greater than the LAA for all algae species. We also hypothesized that Phaeophyceae would have the highest TAA compared to the other classes. In this study, 28 species of algae were collected on St. Croix, USVI. The ABTS, H2O2, horseradish peroxidase decoloration method was used to determine the antioxidant activity then scanned using a UV-VIS Spectrophotometer at 730 nm. The antioxidant activities were reported as µmol Trolox Equivalent (TE)/g Dry Weight (DW). For all of the samples tested, Caulerpa prolifera had the highest TAA (97.281 ± 18.475 µmol TE/g DW) while Dictyota jamaicensis had the lowest TAA (1.999 ± 0.889 µmol TE/g DW). Chlorophyta had the highest mean (23.754 ± 29.710 µmol TE/g DW ) of antioxidant activity and Phaeophyta (12.595 ± 11.861 µmol/g DW) had the lowest mean. A one-way ANOVA test showed significant difference between the HAA and LAA (p = 0.0509). A one-way ANOVA test comparing all three groups revealed that there was no statistical difference between their TAA (p = 0.621). Based on this, we didn’t find any significant difference among the antioxidant levels between the groups tested.

Bioactive Compounds and Antioxidant Activities in Different Fractions of Mango Fruits (Mangifera indica L., Cultivar Tommy Atkins and Keitt).

This study aims to describe and compare the distribution of bioactive compounds, the fatty acids profiles, and the TEAC hydrophilic and lipophilic antioxidant activities in different fruit fractions (pulp, peel, and kernel) of two mango cultivars (Tommy Atkins and Keitt). All fractions are sources of health-promoting bioactive compounds. Regardless of cultivars, pulp had the highest content of phytosterols (~150 mg/100 g dw), peels ranked first for pentaciclic triterpenes (from 14.2 to 17.7 mg/100 g dw), tocopherols, carotenoids, and chlorophylls, and kernels for phenolic compounds (from 421.6 to 1464.8 mg/100 g dw), flavonoids, condensed tannins, as well as hydrophilic and lipophilic antioxidant activities. Differences between the two cultivars were evidenced for ascorbic acid, which showed the highest levels in the peels and kernels of Keitt and Tommy Atkins fruits, respectively. Similarly, the concentration of dehydroascorbic acid was higher in the pulp of Tommy Atkins than Keitt. The highest percentage of saturated fatty acids was observed in pulp (~42%) and kernels (~50%), monounsaturated fatty acids in kernels (up to 41%), and polyunsaturated fatty acids in peels (up to 52%). Our results add information to the current knowledge on nutraceuticals’ distribution in different fractions of mango fruit, supporting its consumption as a healthy fruit and suggesting the great potential value of peels and kernels as sources of novel ingredients. Indeed, mango by-products generated during agronomic-to-industrial processing not only causes a significant environmental impact, but economic losses too. In this scenario, boosting research on conventional recovery methods offers eco-friendly solutions. However, green, novel biorefinery technologies may offer eco-friendly and profitable solutions, allowing the recovery of several more profitable by-products, sustaining their continuous growth since many bioactive compounds can be recovered from mango by-products that are potentially useful in the design of innovative nutraceutical, cosmeceutical, and pharmaceutical formulations.

Phytochemical Screening by High-Performance Thin-Layer Chromatography, Antioxidant Activities and Acute Toxicity of Trunk Barks Extracts of <i>Lannea velutina</i> A. Rich

Lannea velutina is a traditional herbal remedy used to treat various diseases, including hypertension (HBP). Herbal medicines are affordable, and some have minimal side effects; they are rich in bioactive components that encourage prevention and treatment. This work uses appropriate experimental paradigms to investigate the phytochemical composition, antioxidant activity, and acute oral toxicity of L. velutina trunk bark extracted in water, methanol, ethyl acetate, dichloromethane, and hexane. According to a high-performance thin-layer chromatography profile, this shrub’s bark contains sterols, saponosides, flavonoids, and tannins. Compared to ethyl acetate and aqueous extracts, the methanol extract had the highest total phenolic (607.06 ± 0.6 mg GAE/g DW), flavonoid (20.97 ± 0.23 mg QE/g DW), and condensed tannins (194.50 ± 0.75 CE/g DW) content. The methanol extract displayed the highest antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capability assay (IC50 = 8.59 g/mL; AAI = 4.66) compared to the other extracts. It exhibited antiradical action comparable to that of Trolox (IC50 = 15.16 g/mL), ascorbic acid (IC50 = 11.94 g/mL), and catechin (IC50 = 11.64 g/mL). The connection between flavonoid concentration and hydrophilic antioxidant activity was robust (r = 0.997). Mice were used to evaluate the acute oral toxicity of ethyl acetate, methanol, and aqueous extracts using guidelines 425 of the Organization for Economic Cooperation and Development. All tested extracts have an estimated LD50 greater than 2000 mg/kg body weight. The truncal bark of L. velutina could be an alternative source for HTA management.

Evaluation of Hydrophilic and Lipophilic Antioxidant Capacity in Spanish Tomato Paste: Usefulness of Front-Face Total Fluorescence Signal Combined with Parafac

The hydrophilic and lipophilic antioxidant activities due to the main bioactive components present in Spanish tomato paste samples were studied, using standardized and fluorescent methods. After extraction, phenolic antioxidants (Folin-Ciocalteu method) and total antioxidant activity (TEAC assay) were evaluated, examining differences between hydrophilic and lipophilic extracts corresponding to different samples. Total fluorescence spectra of extracts (excitation-emission matrices, EEMs) were recorded in the front-face mode at two different ranges: 210–300 nm/310–390 nm, and 295–350 nm/380–480 nm, for excitation and emission, respectively, in the hydrophilic extracts. In the lipophilic extracts, the first range was 230–283 nm/290–340 nm, while the second range was 315–383 nm/390–500 nm for excitation and emission, respectively. EEMs from a set of 22 samples were analyzed by the second-order multivariate technique Parallel Factor Analysis (PARAFAC). Tentative assignation of the different components to the various fluorophores of tomato was tried, based on literature. Correlation between the antioxidant activity and score values retrieved for different components in PARAFAC model was obtained. The possibility of using EEMs-PARAFAC to evaluate antioxidant activity of hydrophilic and lipophilic compounds in these samples was examined, obtaining good results in accordance with the Folin-Ciocalteu and TEAC assays.

The Effect of Hydrothermal Treatment on Metabolite Composition of Hass Avocados Stored in a Controlled Atmosphere.

Avocado cv. Hass consumption has expanded worldwide given its nutritional, sensory, and functional attributes. In this work, avocado fruit from two harvests was subjected to hydrothermal treatment (38 °C for 1 h) or left untreated (control) and then stored for 30 and 50 days in a controlled atmosphere (4 kPa O2 and 6 kPa CO2 at 7 °C) (HTCA and CA, respectively) with subsequent ripening at ~20 °C. The fruit was evaluated for primary and secondary metabolites at harvest, after storage, and after reaching edible ripeness. A decrease from harvest to edible ripeness in mannoheptulose and perseitol was observed while β-sitosterol, hydrophilic and lipophilic antioxidant activity (H-AOX, L-AOX), abscisic acid, and total phenolics (composed of p-coumaric and caffeic acids such as aglycones or their derivatives) increased. HTCA fruit at edible ripeness displayed higher contents of mannoheptulose, perseitol, β-sitosterol, L-AOX, caffeic acid, and p-coumaric acid derivatives, while CA fruit presented higher contents of α-tocopherol, H-AOX, and syringic acid glycoside for both harvests and storage times. The results indicate that a hydrothermal treatment prior to CA enables fruit of high nutritional value characterized by enhanced content of phenolic compounds at edible ripeness to reach distant markets.

Comparative study of wild chamomile plants from the north-west of Morocco: Bioactive components and total antioxidant activity

Morocco presents numerous plants due its localization between the Mediterranean Sea and Atlantic Ocean and the variability of its mountainous terrain, with a rich range of medicinal plants. Cladanthus mixtus (L.) Oberpr. & Vogt and Matricaria chamomilla L., two Asteraceae (Compositae) from Beni Hassane region in north-western Morocco are both used in traditional medicine for the treatment of different ailments. The phenolic and flavonoid contents of roots, stems, leaves, and flowers of both species were determined by using the Folin Ciocalteu and the aluminum chloride methods, respectively. Antioxidant activity of their aqueous and organic compounds was performed applying the robust and widely used method ABTS radical scavenging assay. C. mixtus had a higher phenolic content (115.25 mg GAE g -1 DW) than M. chamomilla (82.99 mg GAE g-1 DW). However, flavonoid content of both plants was very close (33.53 and 32.45 mg QE g-1 DW in M. chamomilla and C. mixtus, respectively). The total phenolic and flavonoid content was high in flowers of both plants. Generally, for all the studied organs of the chosen plants, hydrophilic antioxidant activity was significantly higher than the lipophilic antioxidant activity. The correlation results show that these bioactive components in both plants are the main factor influencing the antioxidant activity. Key words: Cladanthus mixtus, Matricaria chamomilla, Asteraceae, phenolic content, flavonoid content, antioxidant activity.

Effect of high intensity ultrasound on main bioactive compounds, antioxidant capacity and color in orange juice.

Ultrasound is a useful alternative to thermal processing that can be applied to many food products and juices to aid with enzymes and microorganism inactivation and to improve the efficiency of unit operations generally applied in the food industry. The aim of this study was to evaluate the effect of a high-intensity sonication treatment (frequency 20 kHz; intensity 39.4 W/cm2) applied for treatment times from 0 to 105 min on the content of polyphenols, vitamin C, organic acids, and carotenoids, and on the hydrophilic and lipophilic antioxidant capacity and color of orange juice. Treatments were performed in triplicate and data was statistically analyzed. Sonication time did not have a significant effect (P > 0.05) on total polyphenols, total vitamin C, organic acid, and carotenoid contents, lipophilic antioxidant capacity, or juice color. The hydrophilic antioxidant activity and the lutein content increased significantly (P < 0.05) with increased sonication time. These results may be useful as a baseline for the development of sonication treatments that could be used in combination with other traditional and emerging processing approaches to protect the most important bioactive compounds and quality properties of orange juice.