Antioxidant Activity and Determination of Phenolic Compounds from <Emphasis Type="Italic">Eugenia involucrata</Emphasis> DC. Fruits by UHPLC-MS/MS

Fruits have been the focus of several studies aimed at finding new antioxidant sources for protection against the damage caused by reactive species. In this study, the antioxidant activity and the presence of phenolic compounds in all parts (peel, pulp, and seeds) of Eugenia involucrata DC. fruits were evaluated. DPPH^·, ABTS^·+, and ORAC methods were used to determine the antioxidant activity, and an UHPLC-MS/MS method was developed for determining the phenolic compounds (gallic, chlorogenic, ferulic, p-coumaric and ellagic acids, quercetin, and myricetin). In the determination of both antioxidant activity and phenolic composition, the efficiency of solvents with different polarities—methanol/H₂O (80:20, v/v), ethanol/H₂O (80:20, v/v), methanol/acidified water with phosphoric acid pH 3.00 (80:20, v/v), and ethyl acetate—for the extraction of the phenolic compounds, was also evaluated. All parts of E. involucrata fruits showed antioxidant activity, in the range of 36.68 ± 1.44 to 873.87 ± 18.24 μmol TE g^?1, being the highest values found in the seeds and peel when more polar extraction solvents were used. Six, five, and three phenolic compounds were identified and quantified in the pulp, peel, and seeds, respectively, with the highest abundance as p-coumaric acid (14 ± 2 mg kg^?1) in the pulp, quercetin (47 ± 5 mg kg^?1) in the peel, and gallic acid (74 ± 4 mg kg^?1) in the seeds, also when more polar solvents were used. Although antioxidant activity methods suggested that the peel and seeds have more antioxidant potential, a wider variety of compounds were determined in the pulp.     

Optimization of Extraction Parameters of Total Phenolics from <Emphasis Type="Italic">Annona crassiflora</Emphasis> Mart. (Araticum) Fruits Using Response Surface Methodology

In this study, response surface methodology was used to optimize the extraction temperature (25–75 °C) and ethanol concentration (0–70 %, ethanol/water, v/v) to maximize the extraction of total phenolic compounds (TPC) from araticum pulp. The efficiency of the extraction process was monitored over time, and equilibrium conditions were reached between 60–90 min. A second-order polynomial model was adequately fit to the experimental data with an adjusted R ² of 0.9793 (p < 0.0001) showing that the model could efficiently predict the TPC content. Optimum extraction conditions were ethanol concentration of 46 % (v/v), extraction temperature of 75 °C and extraction time of 90 min. Under the optimum conditions, the araticum pulp showed high TPC content (4.67 g GAE/100 g dw) and also high antioxidant activity in the different assays used (46.56 μg/mL, 683.65 μmol TE/g and 1593.72 μmol TE/g for DPPH IC₅₀, TEAC and T-ORAC_FL, respectively). From our extraction procedure, we successfully recovered a significantly higher amount of TPC compared to other studies in the literature to date (1.5–22-fold higher). Furthermore, TPC and antioxidant activity were present in the fruit in levels that are difficult to find in other common fruits. These results expose a potential approach for improving human health through consumption of araticum fruit.     

Optimization of ultrasonic-assisted extraction of phenolic compounds from <Emphasis Type="Italic">Justicia spicigera</Emphasis> leaves

A Box–Behnken design (Extraction-time, pulse-cycle, sonication-amplitude) was employed to extract phenolic compounds from Justicia spicigera leaves by ultrasonic-assisted extraction. The muicle leaves extracts were analyzed measuring total phenolic compounds and antioxidant capacity. According to response surface methodology the optimal conditions of ultrasonic-assisted extraction to obtain the highest soluble phenolic content were 2 min (extraction time) for 0.7 s (pulse cycle) at 55% of sonication amplitude. Under these optimal conditions, the total phenolic content was higher when was used ultrasonic-assisted extraction (54.02 mg/g) than stirring (46.46 mg/g) and thermal decoction (47.76 mg/g); however, the antioxidant capacity from J. spicigera extracts did not increase by ultrasonic-assisted extraction. The extracts or aqueous infusions from J. spicigera leaves are used for therapeutic proposes, therefore the ultrasonic-assisted extraction is a useful technology to improve the extraction of phytochemicals from J. spicigera leaves.     

Simultaneous Determination of Phenolic Compounds in Different Matrices using Phenyl-Hexyl Stationary Phase

A novel unique liquid chromatographic method has been developed consisting of diode array and fluorescence detection, using phenyl-hexyl stationary phase of the column, for the determination of over thirty phenolic compounds (anthocyanins, flavonols, flavan-3-ols, hydroxybenzoic acids, hydroxycinammic acids, and stilbenes). The method was validated including the following parameters: linearity, limits of detection and quantification, precision, and reproducibility. Excellent selectivity and sensitivity have been achieved. Detection levels ranging from 1.79?×?10^?5 mg/L to 0.26 mg/L were obtained. New fluorescence wavelengths for detection of flavan-3-ols (λ _ex?=?225 and λ _em?=?320 nm) were more sensitive than previously published. The new optimized method showed good repeatability and reproducibility, and values for relative standard deviations (RSD) were less than 3 %. Applicability of the method was demonstrated for five different matrices, white and red wine from Vitis vinifera cultivars, apple cider, blackberry wine, and grape skin extracts, showing that method is robust and can be applied for routine analysis.     

Partition Behaviors of Different Polar Anthocyanins in Aqueous Two-Phase Systems and Extraction of Anthocyanins from <Emphasis Type="Italic">Nitraria tangutorun</Emphasis> Bobr. and <Emphasis Type="Italic">Lycium ruthenicum</Emphasis> Murr.

This study aimed to investigate the partition behaviors of various polar anthocyanins in NaH₂PO₄/(NH₄)₂SO₄-ethanol aqueous two-phase systems (ATPS) and to extract anthocyanins from Nitraria tangutorun Bobr. and Lycium ruthenicum Murr. Anthocyanins in Hibiscus sabdariffa L., Morus atropurpurea Roxb., N. tangutorun, and L. ruthenicum were profiled using HPLC-ESI-MS/MS and HPLC-DAD, and the partition behaviors of total anthocyanins and main anthocyanins were studied. The partition coefficient of anthocyanins increased with increased hydrophobicity, and low-polarity anthocyanins exhibited a higher preference for the top phase in NaH₂PO₄/(NH₄)₂SO₄-ethanol ATPS. Additionally, the NaH₂PO₄-ethanol ATPS gave higher selectivity and total anthocyanin yield than the (NH₄)₂SO₄-ethanol system. Extraction at 65 °C for 45 min and at 45.5 °C for 45 min using 28% NaH₂PO₄ and 26% ethanol (w/w) led to the recovery of 98.91 ± 0.03% of N. tangutorun anthocyanins (3.62 ± 0.05 mg/g) and 99.84 ± 0.01% of L. ruthenicum anthocyanins (13.16 ± 0.29 mg/g) from raw material; more than 70% of total sugars were removed in a single step. NaH₂PO₄-ethanol aqueous two-phase extraction is a promising method for extracting anthocyanins from N. tangutorun and L. ruthenicum.     

Screening of the phenolic profile and their antioxidative activities of methanol extracts of <Emphasis Type="Italic">Myrica rubra</Emphasis> fruits,leaves and bark

The phenolic composition in dried Myrica rubra fruits, leaves and bark were investigated for evaluation of its contribution to the antioxidant activity. The fruits, leaves and bark have the abundant phenolic compounds with the total phenolic content of 0.673, 0.276 and 0.136 mg/g (GA equivalents/FW), respectively. Ten phenolic compounds were isolated and identified in methanol extracts of Myrica rubra fruits by GC–MS analysis. Less phenolic compounds were found in leaves and bark than in fruits. However, the leaves and bark contain much higher concentrations of the trans-resveratrol over 100 μg/g than in fruits. The total antioxidant activities against the ·DPPH radical of those three samples were 0.438, 0.184 and 0.092 mg/g (Trolox equivalents/FW), respectively. The quantitative results indicated that a good correlation between the total antioxidant activity, total phenolic contents, and abundance of individual phenolic compound in Myrica rubra plants.     

An approach for extraction,purification, characterization and quantitation of acylated-anthocyanins from <Emphasis Type="Italic">Nitraria tangutorun</Emphasis> Bobr. fruit

In the present study, a systematic approach for extraction, purification and analysis of acylated-anthocyanins from Nitraria tangutorun Bobr. fruit was explored. Six acylated-anthocyanins in N. tangutorun fruit were identified by HPLC-MS/MS, and a rapid and efficient HPLC-DAD method was developed to analyze the acylated-anthocyanins. Ultrasonic-assisted extraction conditions of acylated-anthocyanins were optimized using response surface methodology, extraction at 70 °C for 32 min using 70% methanol solution (0.1% HCl, v/v) rendered an extract with 80.37?±?2.66 mg/100 g of cyanidin-3-O-(trans-p-coumaroyl)-diglucoside and 97.88?±?4.06 mg/100 g of total acylated-anthocyanins. Nine macroporous resins were investigated for preliminary purification of acylated-anthocyanins. According to the static/dynamic adsorption and desorption tests, XDA-6 macroporous resin exhibited the maximum potential for preparing acylated-anthocyanins. The purity of cyanidin-3-O-(trans-p-coumaroyl)-diglucoside (43.30 mg/g) in purified acylated-anthocyanins was 201.89 times of that of the extract (0.21 mg/g), and the purity of total acylated-anthocyanins increased from 0.36 to 56.44 mg/g. Besides, the stability (t _1/2) of cyanidin-3-O-(trans-p-coumaroyl)-diglucoside and total acylated-anthocyanins increased by more than five-fold after purification using XDA-6. The established methods of analysis, extraction and purification of acylated-anthocyanins were hopefully utilized in food industry.     

Effect of Tannin Extracts on Biofilms and Attachment of <Emphasis Type="Italic">Escherichia coli</Emphasis> on Lettuce Leaves

Lettuce is often involved in foodborne outbreaks caused by pathogenic Escherichia coli. Current control strategies have often proved ineffective to ensure safe food production. For that reason, the present study compared the efficacy of tannin extracts and chlorine treatments on the reduction of E. coli ATCC 25922 adhered to lettuce leaves. E. coli was inoculated artificially on leaf surfaces of fresh crisp lettuce. Effectiveness of water, chlorine (200 mg/L), and three commercial available tannin extracts from Acacia mearnsii De Wild. (tannin AQ (2 %, w/v), tannin SG (1 %, v/v) and tannin SM (1 %, v/v)) treatments was evaluated using the viable plate count method and scanning electron microscopy (SEM). SEM results revealed that bacterial cells are attached as individual cells and in clusters to the leaf surface after 2 h of incubation. Biofilm formation was observed after 24 h of incubation. The tannin SM treatment was able to reduce counts in approximately 2 log CFU/cm² on leaf segments. However, treatment was less effective in the reduction of E. coli counts after 24 h of incubation when compared to 2 h incubation of the same extract. The results suggest that the tannin SM extract diminishes E. coli counts adhered to and under biofilm formation on lettuce leaves and its effect is similar to the use of chlorine solutions.     

LC-ESI-MS/MS Analysis and Extraction Method of Phenolic Acids from Gluten-Free Precooked Buckwheat Pasta

In many countries, common buckwheat (Fagopyrum esculentum Möench) has been cultivated for its nutritive value as food ingredient. This plant is a rich source of vitamins and exogenic amino acids. Many of the health-promoting effects of F. esculentum have been attributed to a large amount of phenolic compounds. Presented in this paper, precooked buckwheat pasta, produced by extrusion cooking, is a gluten-free product without any technological additives. Moreover, it contains natural polyphenolic antioxidants and therefore could be classified as convenience food. The phenolic acid compositions of precooked buckwheat pasta were as follows: gallic, protocatechuic, gentisic, 4-OH-benzoic, vanillic, trans-caffeic, cis-caffeic, trans-p-coumaric, cis-p-coumaric, trans-ferulic, cis-ferulic, and salicylic. A very important step of sample pretreatment before quantitative analysis is the choice of extraction conditions. Therefore, in this study, before quantitative analysis (liquid chromatography-mass spectrometry, LC-ESI-MS/MS), optimization of ultrasound-assisted extraction (UAE) of phenolic acids from precooked buckwheat pasta was performed. The most effective conditions for the isolation of phenolic acids from precooked buckwheat pasta with the use of UAE were as follows: 80 % aqueous ethanol, 60 °C, ultrasound frequency 20 kHz, power 100 W, and time 40 min.     

Reversed-phase HPLC determination of mangiferin,isomangiferin and hesperidin in <Emphasis Type="Italic"> Cyclopia </Emphasis>and the effect of harvesting date on the phenolic composition of <Emphasis Type="Italic"> C. genistoides</Emphasis>

A reversed-phase HPLC method for separation of polyphenols in honeybush tea (Cyclopia spp.) is presented. Separation of eriodictyol, luteolin, medicagol, formononetin, mangiferin, isomangiferin, hesperetin and hesperidin was investigated. A C12 stationary phase was required to separate mangiferin and isomangiferin. The method was used to quantify the three major polyphenols (mangiferin, isomangiferin and hesperidin) in C. genistoides, C. intermedia, C. maculata and C. sessiliflora and to study the effect of harvesting date on these compounds in two types of C. genistoides. The highest levels of the xanthones, mangiferin (3.61 g/100 g) and isomangiferin (0.54 g/100 g), and the flavanone, hesperidin (1.74 g/100 g), were found for C. genistoides (both xanthones) and C. intermedia, respectively. Cyclopia sessiliflora contained the lowest levels of mangiferin (1.04 g/100 g) and hesperidin (0.29 g/100 g). The mangiferin content of both the Overberg and West Coast types decreased with harvesting date (P <0.05). The Overberg type contained more mangiferin, but hesperidin was more prominent in the West Coast type.     

Effect of different solvents on volatile and non-volatile constituents of red bell pepper (<Emphasis Type="Italic">Capsicum annuum</Emphasis> L.) and their in vitro antioxidant activity

The fresh fruit of Capsicum annuum L. (red bell pepper) was successively extracted using n-hexane, chloroform, ethyl acetate, ethanol and their percentage yield was calculated. The effectiveness of each extract on chemical composition and antioxidant activity was studied. The qualitative phytochemical evaluation of each extract of bell pepper was done by HPTLC and Gas chromatography–mass spectroscopy (GC-MS) analysis. The total content of phenols, flavonoids and carotenoids were estimated by standard chemical methods. Further, the antioxidant potential of each extract was measured via DPPH and reducing power assays. Gas chromatography–mass spectroscopy analysis showed that the majority of compounds were related to phenols and flavonoids. Further analysis of the extract by HPTLC verified the presence of different types of phenolic compounds in addition to flavonoids and carotenoids. Among the different solvent extracts analyzed, total phenolic content was higher in ethanol extract (7.136?±?0.03%, w/w) whereas ethyl acetate extract showed the presence of higher flavonoid content (4.0521?±?0.03%, w/w). The ethanol and ethyl acetate extracts of the fruit of C. annuum exhibited the highest radical scavenging activity with inhibition percentage of 53.66 and 49.55% at a concentration of 254 µg/ml. Based on the biochemical analysis and phytochemical screening, we conclude that C. annuum possess potent antioxidant potential and this ability of the extract is attributed to the presence of rich polyphenolic compounds.     

Screening of Phenolic Antioxidants in Edible Oils by HPTLC-DPPH Assay and MS Confirmation

The cytotoxicity of phenolic antioxidants had attracted marked attention, posing serious challenges to food safety. This paper presented a screening method for two major phenolic antioxidants (butylated hydroxytoluene and tert-butylhydroquinone) added in edible oils. To specifically visualize the targeted compounds after developing with toluene/ethyl acetate/methanol 8:1:1 (v/v/v) to 70 mm solvent front, the plate was subjected to a standardized 1,1-diphenyl-2-picrylhydrazyl assay. In addition to synoptical eye inspection, accurate quantification was realized by modified densitometric measurements: fluorescence mode, excitation wavelength 530 nm (D₂ and W lamp) without optical filter, which offered satisfactory sensitivity (8.5–17.5 mg/kg) and acceptable linearity (R²?>?0.999 within 50–200 ng/zone). Moreover, the established method was validated with edible oil samples, against EU Directive 2006/52/EC. Apart from that, the unambiguous confirmation of positive results was conveniently achieved by TLC-MS interface-mediated mass spectrometry. Featuring the merits of screening conception, the proposed method not only reached the goal of accurate quantification and conclusive identification of multi-phenolic antioxidants, but also excellently balanced the simplicity, detectability, and throughput of the screening workup. Therefore, it might be an attractive alternative to conventional methods.     

Development and characterization of reconstituted hydrogel from <Emphasis Type="Italic">Aloe vera</Emphasis> (<Emphasis Type="Italic">Aloe barbadensis</Emphasis> Miller) powder

Structural and rheological characterization of reconstituted hydrogels developed from A. vera non-fibrous alcohol insoluble residue (NFAIR) powder using different methods [viz., shaking (S), heating-shaking (HS), and heating (H)] and concentrations (viz., 0.2–1.6 %, w/v) was carried out. Functional group distribution by FTIR spectroscopy and Congo red (CR) method revealed the presence of acetylated acemannan in A. vera powder. Dynamic oscillation studies of A. vera (NFAIR) fluids at all concentrations of 0.2–1.6 %, w/v, showed gel strength in the order of H > HS > S method. However, in H method, increase in concentration from 0.2 to 1.6 %, w/v showed the conformational transition from semi-diluted solution to weak gel nature. Rheological models described the effect of heating temperatures (HT); 30–90 °C, and times (Ht); 15–60 min on viscoelastic behavior in reconstituted A. vera fluids. The reconstituted A. vera hydrogel prepared with a concentration of 1.6 %, w/v using 50 °C (HT) and 30 min (Ht) condition showed a good agreement with the Power law (storage modulus, G′) and Weak gel model (complex modulus, G*) fitted data (R² > 0.94) resulting higher viscoelastic moduli intercepts; G′₀ (71.5 Pa s ^n′), G″₀ (33.5 Pa s ^n″), lower slopes; n′ (0.22), n″ (0.06), higher network strength (A _F , 121.3 Pa s^1/z ) and number of network (z, 5.3) values. The obtained results suggested that heating at 50 °C/30 min can develop aqueous weak gel networks of A. vera with enhanced gel strength which may be utilized as a novel gelling agent for wide variety of targeted applications in food and pharmaceutical sectors.     

Preparation and Release Behavior of Gelatin-Based Capsules of Antioxidants from Ethanolic Extracts of Thai Riceberry Bran

This study aimed to devise an environment-friendly and effective, yet simple and practicable, antioxidant extraction and encapsulation method from Riceberry bran, whose extract was used thereafter for developing highly efficient antioxidant capsules. Ethanolic Riceberry bran extracts with high total phenolic content, total flavonoid content, total anthocyanin content, and antioxidant activity (using DPPH radical scavenging activity and ferric reducing antioxidant power assay) were obtained using ultrasonic-assisted extraction. The optimum conditions for producing the capsules, such as types of gelatin, concentrations of gelatin, and the Riceberry bran extract concentrations, were studied. Capsules produced by incorporating 1% (w/v) of acid-treated gelatin (type A) and 1% (w/v) of Riceberry bran extract yielded higher chemical properties. When dispersed in water at 37 °C, the capsules exhibited a high release of antioxidants. Moreover, the capsule showed a lower degradation rate of antioxidants under simulated gastrointestinal conditions compared to the crude extract.     

Characterization of Biodegradable Films Based on <Emphasis Type="Italic">Salvia hispanica</Emphasis> L. Protein and Mucilage

Biodegradable films of chia by-products (mucilage and protein-rich fraction (PF)) incorporated with clove essential oil (CEO) were obtained and characterized. The effects of polymer concentration (PC; 1.0–3.0 %, w/v) and CEO concentration (0.1–1.0 %, v/v) were evaluated as well as the pH (7–10), using a 2³ factorial design with four central points. The films exhibited moisture values between 11.6 and 52.1 % (d.b.), which decreased (p?<?0.05) with increasing PC and CEO. The thickness of the films increased (p?<?0.05) with increasing PC. PC and pH influenced (p?<?0.05) the lightness (L) and variation in color between red and green (a). The orientation of the color to yellow-blue hues (b) decreased significantly (p?<?0.05) with increasing PC. Transparency was significantly lower and higher (p?<?0.05) than PC and CEO, respectively. The film surface morphology was evaluated using atomic force miscrocope images, and thermogravimetric analysis (TGA) was performed to study the thermal stability of the films. The displacement and tensile strength were significantly lower (p?<?0.05) at higher concentrations of CEO, this variable being the only one with a significant effect. The chemical composition of the films was confirmed utilizing Fourier transform infrared (FTIR) spectroscopy. The proportion of CEO added to the films had a significant influence on antimicrobial activity, inhibiting the growth of both Escherichia coli and Staphylococcus aureus.     

Optimization of Extraction of Bioactive Compounds from Black Carrot Using Response Surface Methodology (RSM)

In this study, optimum conditions for the extraction of black carrot anthocyanins were determined by response surface methodology. Central composite design of extraction factors (pH 2.5–6.5, temperature 4–72 °C, solvent/solid ratio 5:1–25:1 v/w, ethanol/water ratio 0:100–100:0?v/v) was generated as two replicates. Total phenolic content, total monomeric anthocyanin content, polymeric color, total antioxidant activity, and anthocyanin composition determined by high-performance liquid chromatography were used as responses. Except for color analysis, higher temperature, solid/solvent ratio, and ethanol concentration were observed to increase the extraction yield. However, polymeric color results were found to have minimum values at lower pH and solid/solvent ratio, lower or moderate temperature, and higher ethanol concentration. Optimum extraction conditions were found as follows: 50 °C, pH 3.5, solvent solid ratio 10:1 (v/w), and ethanol/water ratio 75:25 (v/v) when all responses were considered. The validation of the optimum conditions for black carrot extraction was performed at specified values.     

Ultrasound-assisted extraction of bioactive compounds from <Emphasis Type="Italic">Malva sylvestris</Emphasis> leaves and its comparison with agitated bed extraction technique

The effects of ultrasound-assisted extraction (UAE) variables—namely extraction temperature (40–60 °C), ultrasonic power (50–150 W), and sonication time (40–60 min)—on the extractive value (EV) of bioactive phenolics from Malva sylvestris leaves were investigated and optimized using Response surface methodology. The effects of extraction solvents (ethanol, ethyl acetate, and n-hexane) on EV, free radical scavenging activity (FRSA), total phenolic content (TPC), and major bioactive phenolics were studied using agitated bed extraction (ABE), and the results were compared with the UAE findings. Under the optimal UAE conditions (48 °C, 110.00 W, and 48.77 min) the experimental EV was 279.89 ± 0.21 mg/g with 71.12 ± 0.15% DPPH_sc, 73.35 ± 0.11% ABTS_sc, and a TPC of 152.25 ± 0.14 mg GAE/g. Ethanolic ABE results in higher EV (320.16 ± 0.25 mg g^?1) compared to UAE, while the FRSA and TPC values were reduced. HPLC analysis revealed that the concentration of bioactive phenolics increased significantly (p < 0.05) under the optimal UAE conditions.     

Contribution of minor compounds present in the peppermint (<Emphasis Type="Italic">Mentha piperita</Emphasis>) to the iron-catalyzed lipid oxidation of soybean oil-in-water emulsion

This study evaluated contribution of minor compounds naturally present in peppermint (Mentha piperita) to the iron-catalyzed lipid oxidation of oil-in-water emulsion. Emulsions consisted of tocopherol-stripped soybean oil and pH 4.0 citrate buffer (4:6, w/w) with iron. Minor compounds included α-tocopherol, rosmarinic acid, caffeic acid, β-carotene, and chlorophyll b at natural concentration in 400 ppm of the peppermint extract. The emulsions were oxidized in the dark, and headspace oxygen contents, hydroperoxide contents, and p-anisidine values were determined. Addition of phenolic compounds decreased headspace oxygen consumption and hydroperoxide and p-anisidine values of emulsions, however, β-carotene or chlorophyll b tended to increase them. The results suggest that tocopherols at low concentration were the most important to reduce lipid oxidation of emulsions via radical scavenging, followed by high contents of polyphenols via radical scavenging and iron-chelation. Carotenoids and chlorophylls should be precisely controlled even in the dark, possibly due to their oxidation products.     

Volatile Constituents of Jambolan (<Emphasis Type="Italic">Syzygium cumini</Emphasis> L.) Fruits at Three Maturation Stages and Optimization of HS-SPME GC-MS Method Using a Central Composite Design

The volatile compounds of jambolan (Syzygium cumini L.) fruit were determined at three different maturity stages (unripe, half-ripe, and ripe) by headspace solid-phase microextraction (HS-SPME)–gas chromatography-mass spectrometry (GC-MS) technique using five different fibers (Fused silica PDMS/DVB, DVB/CAR/PDMS, PEG, Stable flex PDMS/DVB, and PDMS). The optimal extraction conditions were evaluated using different variables such as adsorption temperature (minimum 25 °C, maximum 55 °C), salt quantity (minimum 0, maximum 30.0%), and extraction time (min 10, max 30 min). The major classes of compounds identified were ester, terpene, alcohol, aldehyde, and carboxylic acid. Ninety volatile compounds with characteristics aroma attributes were identified, and the primary compounds linked with development of characteristics aroma of ripe jambolan fruit pulp were trans-β-ocimene, β-ocimene, caryophyllene, humulene, D-α-pinene, L-β-pinene, β-pinene, D-limonene, α-terpineol, neo-allo-ocimene, 2-hexenal (E), δ-cadinene, 3-hexen-1-ol, (Z) β-linalool, terpinolene, eremophilene, valencene, 1-hexanol, longipinene, γ-terpinene, γ-muurolene, endo-borneol, o-cymene, nonanal, terpinen-4-ol, β-terpineol, α-muurolene, fenchol, α-fenchene, β-thujene, benzaldehyde, (E)-2-hexenal, β-cadinene, and decanal.     

Effect of Cold Atmospheric Plasma on Inactivation of <Emphasis Type="Italic">Escherichia coli</Emphasis> and Physicochemical Properties of Apple,Orange, Tomato Juices,and Sour Cherry Nectar

In this study, orange, tomato, apple juices, and sour cherry nectar were exposed to an atmospheric pressure plasma jet. Plasma treatments were carried out using air as a precursor under constant gas flow (3000 L/h) at 650 W for different treatment times (30, 60, 90, and 120 s). After plasma processing, reduction of Escherichia coli, Hunter’s color parameters (L*, a*, b*), total phenolic content, and pH values were evaluated. The inactivation effect of cold atmospheric plasma (CAP) was investigated on E. coli, and the highest significant reductions were achieved in apple juice (4.02 ± 0.03 log CFU/mL) followed by sour cherry (3.34 ± 0.09 log CFU/mL), while the values in orange (1.59 ± 0.17 log CFU/mL) and tomato juices (1.43 ± 0.22 log CFU/mL) were lower, which could be attributed to the food matrix. Color parameters, except for apple juice, did not show significant changes after processing. Compared to untreated juice, plasma treatment yielded higher phenolic content from 10 to 15%, while pH values did not change significantly and the temperature remained below 40 °C after all plasma treatments. This study showed that CAP treatment had positive influences on phenolic stability and color change in all samples regardless of food intrinsic factors, while it was more effective on bacterial inactivation in clear juices than turbid ones. Our results indicate that atmospheric plasma appears to be a promising technology for microbial inactivation without causing undesirable changes in food product.