Consumer Acceptability and Sensory Profile of Cooked Broccoli with Mustard Seeds Added to Improve Chemoprotective Properties

Broccoli, a rich source of glucosinolates, is a commonly consumed vegetable of the Brassica family. Hydrolysis products of glucosinolates, isothiocyanates, have been associated with health benefits and contribute to the flavor of Brassica. However, boiling broccoli causes the myrosinase enzyme needed for hydrolysis to denature. In order to ensure hydrolysis, broccoli must either be mildly cooked or active sources of myrosinase, such as mustard seed powder, can be added postcooking. In this study, samples of broccoli were prepared in 6 different ways; standard boiling, standard boiling followed by the addition of mustard seeds, sous vide cooking at low temperature (70 °C) and sous vide cooking at higher temperature (100 °C) and sous vide cooking at higher temperature followed by the addition of mustard seeds at 2 different concentrations. The majority of consumers disliked the mildly cooked broccoli samples (70 °C, 12 min, sous vide) which had a hard and stringy texture. The highest mean consumer liking was for standard boiled samples (100 °C, 7 min). Addition of 1% mustard seed powder developed sensory attributes, such as pungency, burning sensation, mustard odor, and flavor. One cluster of consumers (32%) found mustard seeds to be a good complement to cooked broccoli; however, the majority disliked the mustard‐derived sensory attributes. Where the mustard seeds were partially processed, doubling the addition to 2% led to only the same level of mustard and pungent flavors as 1% unprocessed seeds, and mean consumer liking remained unaltered. This suggests that optimization of the addition level of partially processed mustard seeds may be a route to enhance bioactivity of cooked broccoli without compromising consumer acceptability.     

Antioxidative, antiradikale und antimikrobielle Aktivitäten des Fruchthüllen-Extrakts von frischen Antep-Pistazien

Pistacia vera L. is the only genus of more than ten in Pistacia species consumed as a nut and has commercial value. Turkey is one of the homelands of the pistachio species, and they are named Antep pistachio. When Antep pistachios are processed into nuts, their reddish purple hulls are removed as a waste after the processing. In this research, Antep pistachio hull samples extracted by methanol, ethanol and water were tested for antioxidant and antiradical (IC₅₀ value) potentials, and antimicrobial activities as well. The values of total phenolic content of methanol extracts of Antep pistachio hull was 167.49 ± 0.48 mg gallic acid equivalent (GAE)/g dry extract. The ethanol and aqueous extract of the pistachio hulls were determined as 89.87 ± 0.44 and 31.73 ± 0.21 mg GAE/g dry extract, respectively. The antioxidant activities of extracts were evaluated by the phosphomolybdenum method. The highest antioxidant activity of the hull extracts was determined in the methanol extracted samples (152.10 ± 0.19 mg ascorbic acid equivalent (AAE)/g dry extract), while the lowest value was in the ethanol extracts (15.19 ± 0.00 mg AAE/g dry extract). The values of IC₅₀ in methanol, ethanol and aqueous extracts of the pistachio hulls were 16.01, 21.62 and 24.45 μg/ml, respectively. The highest antiradical activity was in the methanol extract of Antep pistachio hulls. In this research, the pistachio hull extracts were tested for antimicrobial activities against total 15 microorganisms, 13 bacteria and 2 yeasts. The aqueous extract of the hull was the most ineffective extract against the microorganisms tested. The methanol and ethanol extracts of the pistachio hulls, which had limited antimicrobial effect against the bacteria, Mycobacterium smegmatis, Salmonella typhimurium, Proteus mirabilis and Yersinia enterocolitica, and the yeasts, Saccharomyces cerevisiae and Candida albicans, and were effective on the other microorganisms constituted inhibition zones diameter as between 10 and 39 mm. All extracts of the pistachio hulls exhibited antimicrobial activity against Listeria monocytogenes (6–38 mm) and Escherichia coli O157: H7 (8–28 mm). In conclusion, the hulls of Antep pistachio can be evaluated as a potential antimicrobial and antioxidant resource in the food systems.     

Purification of major glucosinolates from Brassicaceae seeds and preparation of isothiocyanate and amine metabolites

Consumption of Brassica vegetables containing glucosinolates is associated with decreased risk of cancer at several tissue sites. Studies of the relative potency and metabolism of the major dietary isothiocyanates have been hindered by limited availability of high‐purity isothiocyanates and their glucosinolate precursors. We describe a simple procedure for the preparation of glucosinolates sinigrin, gluconapin, progoitrin, glucoiberin, glucoraphanin, glucoalyssin and gluconasturtiin from vegetable seeds. Glucosinolates were extracted from the seeds of mustard, oilseed, broccoli, cauliflower and winter cress. Purification by preparative anion exchange and reversed‐phase column chromatography gave the pure glucosinolates. Good separation was achieved without using ion‐pair reagents. Related isothiocyanates and amine degradation products were prepared by myrosinase‐catalysed hydrolysis of the corresponding glucosinolate and by organic synthesis, respectively. The compounds were characterized by analytical HPLC, ¹H NMR, ¹³C NMR, elemental analysis and mass spectrometry. Optimized conditions for detection and quantitation of these glucosinolates and metabolites by LC‐MS/MS are also given. Large‐scale glucosinolate preparation could be performed, giving amounts suitable for pharmacological evaluation in vivo. These methods will facilitate studies of the pharmacological activity and metabolism of dietary glucosinolates. Copyright © 2006 Society of Chemical Industry     

Development of a Novel Functional Soup Rich in Bioactive Sulforaphane Using Broccoli (Brassica oleracea L. ssp. italica) Florets and Byproducts

Broccoli florets are rich in health-promoting compounds such as glucoraphanin, the precursor of the bioactive compound sulforaphane. In addition, broccoli byproducts such as stalk also contain health-promoting compounds and represent attractive ingredients in the development of functional foods. The bioconversion of glucosinolates into bioactive isothiocyanates is affected by many factors including heat and therefore cooking of Brassica such as broccoli may result in significant loss of sulforaphane production. The aim of this study was to develop a suitable food system as a vehicle for the delivery of sulforaphane in the human diet in adequate quantities. To this end, the feasibility of dry-mix ready soup as a food matrix for the delivery of broccoli floret and byproducts was evaluated. In particular, this study investigated the bioconversion of glucosinolates into bioactive isothiocyanates during the cooking process of this novel food product by microwave heating. In addition to total isothiocyanate and sulforaphane content, other key physical and biochemical quality attributes of the broccoli floret- and byproduct-enriched soups were investigated. Total isothiocyanate and sulforaphane content in floret- and stalk-enriched soups was high in both cases and increased in the order stalk<floret. The overall acceptability of stalk containing soups was not significantly different compared with the control soups, whereas floret containing soups received significantly lower acceptability scores. These results suggest that ready soups prepared by microwave heating represent a feasible food product for the delivery of broccoli florets and byproducts which is compatible with the bioconversion of glucosinolates into bioactive isothiocyanates.     

Phenolic composition and comparison of antioxidant activity of alcoholic extracts of Peppermint (Mentha piperita)

Peppermint (Mentha piperita) has long been regarded as a food and medicinal plant. At the present work, the antioxidant activity of the methanol, ethanol and methanol/ethanol (1:1) extracts of leaf fraction through various in vitro models was investigated in Iranian peppermints for the first time. Total phenol, flavonoid and anthocyanin contents were also determined. Our results showed the alcoholic extracts had different responses with different antioxidant methods. The methanol extract had maximum phenol content (3.57 ± 0.26 g Gallic acid/100 g Peppermint powder) and showed best superoxide radical (47.05 ± 0.85 %) and hydrogen peroxide (91.05 ± 1.50 %) scavenging activities. The methanol/ethanol (1:1) extract had maximum flavonoid (3.33 ± 0.12 g quercetin/100 g Peppermint powder) and anthocyanin contents (1.74 ± 0.21 g/100 g Peppermint powder) and showed best DPPH radical scavenging activity (82.82 ± 2.57 %, IC₅₀ = 10.02 ± 0.63 mg/mL) as well as ferric reducing power (184.22 ± 14.10 μmol/100 g Peppermint powder). The ethanol extract only showed the highest nitric oxide radical scavenging activity (80.13 ± 7.12 %). Chlorogenic acid, rutin, and caffeic acid were found by HPLC analysis of the main phenolic components. These results show, Peppermint alcoholic extracts can be used as a natural antioxidants to reduce oxidative stress in human beings and as a possible food supplement or in pharmaceutical applications.     

Antioxidant and antigenotoxic activities of ethanol extracts from Rhus chinensis Mill leaves

Ethanol extracts were obtained from Rhus chinensis Mill (RCM) leaves and used for antioxidant and antigenotoxic activity assays. IC₅₀ values in DPPH assays were 15.96, 18.83, 20.43, 27.93, 37.43, 46.21, and 141.84 μg/mL for TPP, IPE, LLE, Vc, CE, BHT, and Trolox. Similar results were obtained using ABTS and FRAP assays. In vivo testing showed strong antioxidant activities that were positively correlated with polyphenol contents. Leaf tissue contained abundant polyphenols, and more than 10 phenolic compounds were detected in extracts. Quantitative results showed that quercetin-3-rhamnoside (26.4±0.76 mg/g of extract) was the most abundant ingredient, followed by hyperoside (15.2±0.42 mg/g of extract), quercetin (1.5±0.07mg/g of extract), and kaempferol (0.48±0.05 mg/g of extract). This study increases the knowledge for possible uses of forest by-products as a substitute for gallnuts.     

Nutritional constituents,phytochemical profiles, <Emphasis Type="Italic">in vitro</Emphasis> antioxidant and antimicrobial properties,and gas chromatography–mass spectrometry analysis of various solvent extracts from grape seeds (<Emphasis Type="Italic">Vitis vinifera</Emphasis> L.)

The present study revealed that the nutritive value of grape seeds (Vitis vinifera L.) was 383.55±0.13 Kcal/100 g, with magnesium as the most abundant mineral element (70.44±0.88 mg/L). The maximum phenolic (392.58±1.70mg of GAE/g), flavonoid (256.16±1.60 mg of QE/g), and tannin (30.95±0.17mg of CE/g) contents were also found in the ethanol, dichloromethane, and hexane extracts, respectively. The major phytochemical compounds in the ethyl acetate extract were identified via gas chromatography–mass spectrometry (GC–MS) analysis. The ethanol extract has the highest antioxidant activity (IC₅₀=140±1.20 μg/mL for DPPH, 145.28±0.45mg α-tocopherol/g for total antioxidant capacity, and EC₅₀=80±1.41 μg/mL for ferric-reducing power assays). For β-carotene test, the highest antioxidant activity was obtained in the hexane extract. A satisfactory antimicrobial activity was found against a panel of microorganisms with the ethyl acetate extract as the best antimicrobial agent. Additionally, it was found that the bactericidal concentration required for the grape seed extract to kill Listeria monocytogenes should be less than 12.50 mg/mL (minimum inhibitory concentration=4).     

Absorbability of Calcium from Brassica Vegetables: Broccoli, Bok Choy, and Kale

Absorption of calcium from three intrinsically labeled Brussica sp. vegetables was measured in 15 normal women in a three-way randomized design. The test load of calcium was about 83 mg for each source. Fractional calcium absorption from broccoli averaged 0.478 ± 0.089, from bok choy stems, 0.519 ± 0.089, from bok choy leaves, 0.520 ± 0.074, and from kale 0.527 ± 0.091. These differences were both absolutely small and statistically insignificant. Mean absorbability of milk calcium ingested at the same load has been previously shown to be 0.463 ± .095. This value is slightly but significantly lower than the average value for the Brassica sources combined (0.514 ± 0.090). Thus, Brussicu vegetable sources exhibit excellent calcium bioavailability.     

Chemometric-Assisted Optimization of RP-HPLC Method for Determination of Some Bioflavonoids in Brassica oleracea Species and Their Antioxidative Activity

In the present work, the rapid RP-HPLC method with UV (DAD) detection for simultaneous quantification of bioflavonoids: quercetin, apigenin, catechin, epicatechin, kaempferol, and luteolin in Brassica oleracea species samples (cauliflower, broccoli, and Brussels sprouts) was developed with the aid of LC-Simulator (ACD Labs® suite) software. A series of extracts obtained with different extraction method were evaluated for antioxidant activity. The optimal conditions for separation and quantification were established after nine scouting runs entered to LC-Simulator software. The optimized separation was achieved on Hypersil GOLD aQ column with isocratic elution and mobile phase composition A:2 % acetic acid in water and B:acetonitrile in 91:9 (v/v %) ratio. The R _s values were in the range from 2.6 to 8.00, indicating good selectivity of the method. The obtained results generally show good agreement with published data. Low detection limits (0.02–0.055 μg/mL) were obtained with acceptable recoveries (90–109 %). Total time of analysis was less than 11 min; therefore, the proposed method represents significant improvement over existing methods. Extracts from Brassica vegetables, obtained using different extraction procedures, were studied for their radical scavenging effects. Scavenging of DPPH showed different kinetics at the beginning of the assay period and after 15 min from the initialization of reaction. Different kinetics suggested the presence of polymerized and/or less active antioxidants with different scavenging mechanisms for particular polyphenolic compounds.     

Investigation of antibrowning activity of pine needle (Cedrus deodara) extract with fresh-cut apple slice model and identification of the primary active components

Cedrus deodara is a large evergreen tree of the family Pinaceae and widely distributed to the west of Himalayas. Its pine needles are consumed as a traditional food and perceived as a valuable source for bioactive compounds. A recent study has demonstrated Cedrus deodara pine needle extract (CDE) can inactivate tyrosinase. However, possible action mechanism and application of the extract have not been elucidated. In the present study, the application of CDE in food industry was explored using a fresh-cut apple slice model. Through evaluating the variation in a*, b* and L* values, the browning extent of apple slices was found to be inhibited by CDE. Moreover, in order to explore the antibrowning mechanism, we investigated the antioxidant and antibrowning capacities, total phenolic and flavonoid contents and the major bioactive constituents of the extract. It was found CDE showed strong antioxidant activity to scavenge ABTS (SC₅₀, 24.33 μg/mL) and DPPH (SC₅₀, 35.94 μg/mL) radicals, inhibited monophenolase (IC₅₀, 0.76 ± 0.08 mg/mL) and diphenolase (IC₅₀, 1.01 ± 0.09 mg/mL) activities and contained high content of phenolics (76.39 ± 2.27 mg gallic acid equivalent/g extract) and flavonoids (33.23 ± 3.25 mg rutin equivalent/g extract). Furthermore, according to the bioassay-guided isolation and the analysis of high-performance liquid chromatography–mass spectrometry and nuclear magnetic resonance, methylconiferin and ferulic acid-β-d-glucoside were determined to be the main active compounds. The current results provided the possible antibrowning mechanism of CDE and confirmed C. deodara pine needles might be a natural resource for preparing antibrowning agents of vegetables and fruits in food industry.     

Antioxidant activities and bioactive components in some berries

The objective of this study was to evaluate the antioxidant and binding effects of gooseberry, a less-studied berry, and to compare with blueberry and cranberry in the model of interaction with human serum albumin (HSA). The relationship between the scavenging properties of dietary polyphenols of the selected berries and their affinities for HSA were investigated by fluorescence analysis. In order to perform the extraction and identification of the antioxidants present in the samples, different types of extraction solvents were used, such as water, ethyl acetate, and diethyl ether. The polyphenols, tannins, anthocyanins and ascorbic acid contents, and the total antioxidant capacities (TACs) of the berry extracts were assessed by using ESI–MS, FTIR, and radical scavenging assays. The contents of bioactive compounds and the levels of TACs in water extracts differed significantly and were the highest in water extracts in comparison with other extracts in all the investigated berries (P < 0.05). Gooseberry water extracts contained: polyphenols (mg GAE/g DW)—5.37 ± 0.6, tannins (mg CE/g DW)—0.71 ± 0.2, anthocyanins (mg CGE/g DW)—12.0 ± 1.2, ascorbic acid (mg AA/g DW)—5.15 ± 0.5, and TACs (μMTE/g DW) by ABTS and FRAP assays were 15.53 ± 1.6 and 6.51 ± 0.7, respectively. In conclusion, the bioactivity of gooseberry was lower than blueberries and cranberries. The antioxidant and binding properties of gooseberries in comparison with widely consumed blueberries and cranberries can be used as a new source for food supplementation.     

Antioxidant activity and acetylcholinesterase inhibition of field and in vitro grown <Emphasis Type="Italic">Musa</Emphasis> L. species

Bananas and plantains (Musa L. species) have medicinal applications against diseases such as hypoglycemia, hypertension, and neurological disorders, especially Alzheimer’s disease. The demand for these plants is growing very fast, resulting in a relatively heavy load on Musaceae genetic resources. The study evaluated and compared the acetylcholinesterase (AChE) inhibition and antioxidant activity of field and in vitro plant materials of nine accessions of Musa spp. consisting of Tropical Musa banana (TMb: TMb 106, TMb 145, TMb 8, TMb 82, TMb 55) and Tropical Musa plantain (TMp: TMp 116, TMp 24, TMp 36) from the International Institute of Tropical Agriculture and Musa sapientum (MS) from the University of Ibadan Botanical garden, Nigeria. Musa accessions were estimated onto Murashige and Skoog (MS) medium supplemented with 0.18 mg/L indole acetic acid (IAA) and 4.5 mg/L benzyl amino purine (BAP). The in vitro grown accessions behaved differently with TMb 8 having the highest average shoot length of 5.03?±?0.66 cm, and average number of leaves of 5.65?±?0.38 cm at the end of 6 weeks. Leaf extracts provide more quantity of phenolics, flavonoids and higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity than the fruit extracts. The AChEI activity of the field plants ranged from 60.54?±?0.54 to 98.46?±?0.09?% and in vitro plants from 61.88?±?0.11 to 76.60?±?0.34?% at 200 µg/mL. Crude methanol extract (CME) of the in vitro plants showed higher DPPH antioxidant activity than the field plants with IC₅₀ (extract concentration providing 50?% inhibition) values ranging from 9.57?±?0.24 to 48.37?±?0.62 µg/mL compared with CME of the field samples, which had IC₅₀ ranging from 75.86?±?1.76 to 162.20?±?3.77 µg/mL. Plant tissue culture can be a reliable alternative cultivation method for mass propagation and conservation of Musa species for the production of antioxidant and acetylcholinesterase metabolites.     

Time dependence of bioactive compounds and antioxidant capacity during germination of different cultivars of broccoli and radish seeds

Optimisation of the germination process of different cultivars of broccoli (Brassica oleracea var. italica cv. Lucky, cv. Tiburon and cv. Belstar) and radish (Raphanus sativus cv. Rebel and cv. Bolide) seeds in relation to the content of glucosinolates (GLS), vitamin C and total antioxidant capacity was carried out in order to maximise the health-promoting properties of Brassica sprouts. The content of total and individual GLS varied between species, among cultivars, and germination time. Glucoraphanin in broccoli and glucoraphenin in radish were the predominant GLS in raw seeds (61–77 and 63–129 μmol/g DM, respectively) and, although their content decreased during germination, they were maintained in rather large proportions in sprouts. Vitamin C was not detected in raw seeds and its content increased sharply in broccoli and radish sprouts (162–350 and 84–113 mg/100 g DM, respectively). Raw brassica seeds are an excellent source of antioxidant capacity (64–90 and 103–162 μmol Trolox/g DM in broccoli and radish, respectively) and germination led to a sharp increase. Germination of broccoli cv. Belstar and radish cv. Rebel for 4 days provided the largest glucoraphanin and glucoraphenin content, respectively, and also brought about large amounts of vitamin C and antioxidant capacity.     

Antioxidant and antifungal activities of extracts from 15 selected hardwood species of Malaysian timber

The antioxidant activities, total phenols and antifungal activities of 35 extracts samples from 15 species of Malaysian timber were investigated. The methanol extracts from Mangifera indica heartwood were found to have superior antioxidant activity with an EC₅₀ value of 4.71±0.89 μg/ml. Antioxidant activities correlated with total phenols contents. The methanol extracts from Neobalanocarpus heimii bark and Cinnamomum porrectum heartwood showed moderate antifungal activity against a brown-rot fungus, Gloeophyllum trabeum. The methanol extracts from Neobalanocarpus heimii bark and Endospermum malaccense inner wood showed the highest antifungal activity against a white-rot fungus, Pycnoporus sanguineus, at a minimum effective amount of 100 μg. The activities of these extracts were equal to the activity of the positive control, glycyrrhizic acid dipotassium salt, suggesting that they have great potential as a source of fungistats.     

Distribution of glucosinolate and pungent odors in rapeseed oils from raw and microwaved seeds

The current study was aimed to investigate the effect of glucosinolate degradation on the flavor precursors and pungent odors in raw and microwaved rapeseeds. Five isothiocyanates and six sulfur compounds were identified using comprehensive two-dimensional gas chromatography and time-of-flight mass spectrometry (GC× GC-TOF/MS). Comprehensive analysis with headspace solid-phase microextraction (HS-SPME) and aroma extract dilution analysis (AEDA) with altering split ratio showed that 1-isothiocyanato butane, allyl isothiocyanate and 4-isothiocyanato-1-butene were responsible for the sulfur, pungent and green odors in rapeseed oils, due to their high flavor dilution factor. Dimethyl sulfide, dimethyl trisulfide and dimethyl sulfoxide, might be derived from methionine or isothiocyanate rearrangement reactions imparted onion-like, cabbage-like, garlic-like, and sulfurous-pungent odors. Rapeseed samples were heated in a microwave for seven minutes, and the total glucosinolate content decreased from 28.2 ± 0.8 μmol/g to 14.5 ± 0.6 μmol/g in Brassica napus, from 101.2±3.0 μmol/g to 42.2 ± 5.4 μmol/g in Brassica campestris, and from 132.02 ± 9.31 μmol/g to 52.50 ± 6.50 μmol/g in Brassica juncea, compared to untreated ones. Differences in the concentrations of six main odorants and the glucosinolate precursors from genetic types were responsible for the intensity of the pungent odors in raw and microwaved rapeseeds. The result can assist to determine the flavor of the commercial rapeseed oils.     

Bioactivity and mineral contents of wild-grown edible Morchella conica in the Mediterranean Region

In this study, antiradical and antimicrobial activity, total phenolic, mineral and heavy metal content of Morchella conica Pers. were determined in the methanolic extracts of dried M. conica collected from wild-grown edible mushroom in the Mediterranean region from Turkey. Free radical scavenging activity was determined to be 43.72 ± 0.13% DPPH decoloration, however, total phenolic activity to be 20.64 ± 0.33 mg GAE/g dry ext. sample. The antimicrobial activity of the extracts was tested against fourteen microorganism including 12 bacteria and 2 yeasts. It was determined that the mushroom extracts had no effect against the bacteria and yeasts. Antimicrobial effect was determined only against Staphylococcus aureus ATCC 29213. M. conica was determined to contain some heavy metals such as arsenic (As), mercury (Hg), cadmium (Cd), lead (Pb), chromium (Cr) and nickel (Ni) in the concentrations of 0.25, 0.06, 0.20, 1.20, 0.70 and 1.10 (mg/kg dw), respectively. Potassium (K), phosphorus (P) and magnesium (Mg) contents were determined to be 20,400, 13,250, and 1,600 (mg/kg dw), respectively, being higher than those of the other minerals in the M. conica extracts.     

预冷处理结合低温贮藏对西兰花贮藏品质的影响

为探讨预冷处理结合低温贮藏（0 ± 1）℃对西兰花贮藏品质的影响,以“苏青”6号西兰花试验材料,定期感官评定及测定呼吸强度、色差、叶绿素含量、叶绿素酶活性、V_C含量、总硫代葡萄糖苷含量、异硫氰酸酯含量、过氧化物酶活性、过氧化氢酶活性、抗坏血酸过氧化物活性以及丙二醛含量。结果显示,预冷处理结合低温贮藏西兰花,可有效延缓其黄化,保持较低的呼吸强度和较高的维生素C、叶绿素、游离酚、硫代葡萄糖苷和异硫氰酸酯含量,其中异硫氰酸酯含量在第31 d达241.41 mg/100 g·FW;有效保持较高的APX、CAT活性以及DPPH自由基清除能力,有效抑制POD和叶绿素酶活性,降低丙二醛含量。相关性分析显示:西兰花的叶绿素含量与叶绿素酶活性呈极负显著（P<0.01）相关,与POD活性显著（P<0.05）负相关;硫代葡萄糖苷、异硫氰酸酯含量与MDA含量呈显著（P<0.05）负相关。主成分分析结果显示:叶绿素含量、CAT活性、总硫代葡萄糖苷含量、叶绿素酶活性、呼吸强度和丙二醛含量可作为评价西兰花品质特性的关键指标。本研究可为西兰花的保鲜研究提供理论依据。     

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.     

Characterization of Valuable Compounds from Winter Melon (<Emphasis Type="Italic">Benincasa hispida</Emphasis> (Thunb.) Cogn.) Seeds Using Supercritical Carbon Dioxide Extraction Combined with Pressure Swing Technique

In this study, we describe the extraction of different valuable compounds from winter melon seeds using supercritical carbon dioxide extraction combined with pressure swing technique (SCE-PST). The effects of the extraction variables, namely pressure, holding time (HT), and continuous extraction time (CT), were optimized by response surface methodology (RSM) to maximize the crude extraction yield (CEY). The optimal conditions were at pressure of 181.35 bar, HT of 9.93 min, and CT of 50.14 min. Under these conditions, the experimental CEY was 235.70?±?0.11 mg g^?1 with a relatively strong antioxidant activity (64.42?±?0.21 % inhibition of DPPH^· radicals, 67.36?±?0.34 % inhibition of ABTS^·+ radicals) and considerable amount of phenolic compounds (42.77?±?0.40 mg gallic acid equivalent/g extract). The high-performance liquid chromatography (HPLC) analysis revealed that the bioactive phenolic compounds increased significantly using PST (p?<?0.05), where gallic acid had the highest concentration (0.688?±?0.34 mg g^?1). The extract obtained using optimal SCE-PST conditions contained more than 83.65 % total unsaturated fatty acids (UFAs) and linoleic acid accounted for 67.33?±?0.22 % in the total extract. From the results, the SCE efficiency in terms of extract quantity and quality has been enhanced significantly applying PST. Finally, the results were compared with previous published findings using supercritical carbon dioxide, ultrasound-assisted, and Soxhlet extraction. It was found that higher CEY could be achieved using Soxhlet extraction even through the quality of SCE-PST extracts in terms of antioxidant activity and phenolic compounds was better.