Profile of Phenolic Compounds and Antioxidant Activity of Celery (Apium graveolens) Juices Obtained from Pulp after α-Amylase Treatment from Aspergillus oryzae.

The purpose of this study was to determine the content of certain phenolic compounds, antioxidant activity, pressing efficiency, extract content, and sugars in celeriac juices obtained from the pulp after α-amylase treatment from Aspergillus oryzae. The test material consisted of peeled and unpeeled celery pulp kept at a temperature of 25 °C with and without the enzyme for a period of 30 and 60 min. The juices obtained from them were analyzed for the content of selected phenolic acids and flavonoids using the UPLC-PDA-ESI-MS/MS method, for antioxidant activity measured using the ABTS˙+ and DPPH˙ method, and for the total polyphenol content using the F-C method. Additionally, the juice pressing efficiency, the extract content using the refractometer method, and the sugar content using the HPLC method were checked. Significantly higher antioxidant activity, pressing yield, and average content of caffeic acid glucoside, quinic acid, kaempferol-3,7-di-O-glucoside, and chrysoeriol-7-O-apiosylglucoside were obtained in juices from peeled celery. Maceration of the pulp with amylase resulted in a significant reduction in antioxidant activity compared to control samples. An is-total increase of 17-41% in total flavonoid content was observed in all juices tested after treatment with the enzyme for 30 and 60 min, and the phenolic acid content increased by 4-41% after treatment of the pulp with amylase for 60 min. The 60 min holding of the pulp at 25 °C, including with the enzyme, was shown to decrease the antioxidant activity and the content of quinic acid, ferulic acid, and chrysoriol-7-O-apiose-glucoside in the juices tested compared to the samples held for 30 min, while the content of other phenolic acids and flavonoids increased. In addition, after 60 min of enzymatic maceration, the pressing yield of the juices increased.

Effect of Celeriac Pulp Maceration by Rhizopus sp. Pectinase on Juice Quality.

Peeled and unpeeled celeriac pulp was macerated with pectinase from Rhizopus sp. at 25 °C for 30 and 60 min. Peeling, enzyme addition, and maceration time significantly affected the quality characteristics of the juice. The juice obtained from peeled celeriac was characterized by higher pressing yield, sucrose content, and antioxidant activity (ABTS*+ and DPPH*). The juice from the unpeeled root had higher extract, fructose, glucose, total polyphenols, antioxidant activity (FRAP), total phenolic acids, and total luteolin content. Applying the enzyme to celeriac pulp had no significant effect on the extract's content, analyzed sugars, and antioxidant activity of the juices (ABTS*+). Adding pectinase to unpeeled celery pulp resulted in a 2-10% increase in pressing efficiency, compared to the control sample held at 25 °C for the same period. Maceration of the enzyme-peeled pulp increased the antioxidant potential of the juice by 22% in the FRAP method. In contrast, in all juices analyzed, unpeeled and peeled roots increased antioxidant activity measured by the DPPH* method by 24-57% and total phenolic acids by 20-57%. The time of holding the pulp at 25 °C was an important factor, and its extension resulted in a decrease in the values of most of the analyzed parameters, with the exception of pressing efficiency and fructose content in all analyzed juice samples. Short-term, 30-min maceration of peeled and unpeeled celery pulp with pectinase from Rhizopus sp. had a significant effect on increasing juice yield, antioxidant activity, and phenolic compound content.

Genetic mechanism, baseline sensitivity and risk of resistance to oxathiapiprolin in oomycetes.

BACKGROUND: Oxathiapiprolin is a piperidinyl thiazole isoxazoline fungicide discovered by DuPont and commercialized by Corteva Agriscience. It acts by inhibiting a novel fungal target, an oxysterol binding protein (OSBP), and is intrinsically highly active against oomycetes including grape downy mildew (Plasmopara viticola) and potato late blight (Phytophthora infestans). Because the fungicide acts at a single site there is a need to determine the risk of resistance development. RESULTS: Oxathiapiprolin controlled European Plasmopara viticola and Phytophthora infestans isolates at very low concentrations with half maximal effective concentration (EC50 ) values ranging from 0.001 to 0.0264 mg L-1 and 0.001 to 0.03 mg L-1 , respectively. Laboratory mutagenesis studies performed with Phytophthora capsici using ultraviolet (UV) irradiation generated mutants with reduced sensitivity to oxathiapiprolin. All resistant mutants had a base pair change in the OSBP gene that resulted in an amino acid change. Most common substitutions were S768Y, G770V, G839W and L863W. Isolates of Plasmopara viticola and Phytophthora infestans with reduced sensitivity were also detected in field trial sites where oxathiapiprolin had been applied repeatedly each season over several consecutive years. CONCLUSIONS: The risk of oxathiapiprolin resistance development in Plasmopara viticola and Phytophthora infestans is medium to high and strict resistance management measures are required. Over-exposure of target populations to single-site fungicides during product development should be avoided.

Onion juice and extracts for the inhibition of enzymatic browning mechanisms in frozen Agaricus bisporus mushrooms.

BACKGROUND: The potential of onion juice, as well as extracts of waste (tunic) (5%) and fleshy scale leaves (25%), to inhibit enzymatic browning of frozen Agaricus bisporus was investigated. The onion materials were used for blanching and their effectiveness in conserving integrity and appearance of mushroom fruiting bodies was compared with the currently accepted method of blanching in a sodium metabisulfite (SM) solution. RESULTS: It was observed that l-phenylalanine content may be a useful indicator of the changes in enzymatic activity during frozen storage, and l-tyrosine may be an indicator of a loss of lightness in color (parameter L*). The enzymes responsible for color changes were mainly monophenolase (MON) and, to a lesser degree, diphenolase (DIP). After being stored frozen for 8 months, these enzymes were detected at a 29:1 (DIP:MON) ratio in untreated mushrooms and a 2:1 (DIP:MON) ratio in mushrooms treated with onion juice. CONCLUSION: Onion products may be a good alternative to an SM solution. The most effective method to conserve the light color of fruiting bodies was blanching in juice or in an extract of the fleshy scale leaves. The least effective inhibitor of MON was tunic extract, which did, however, cause a favourable increase in the reducing capacity (total polyphenols) and flavonoids. Although the onion waste (tunic) extract changed the color of mushrooms from white to creamy orange, the color of these products was attractive and positively evaluated by panellists. © 2020 Society of Chemical Industry.

The Effect of the Addition of Dietary Fibers from Apple and Oat on the Rheological and Textural Properties of Waxy Potato Starch.

The aim of this paper was to investigate the influence of dietary fibers from oat (OF) and apple (AF) (concentration 0.2%) on the pasting properties, rheological (including thixotropic and anti-thixotropic) and textural properties of 3% and 4% (w/w) waxy potato starch pastes. The samples were characterized by their pasting characteristics, the hysteresis loop test, and textural properties measured during storage. It was found that the breakdown viscosity values of the blends, including oat fibers, were lower than those of the others (waxy potato starch (WPS), WPS-AF), which suggests that these samples would have higher resistance to retrogradation and therefore would form a more stable paste. The pattern of flow curves showed that the investigated waxy potato starch and starch-fiber pastes were non-Newtonian fluids, thinned by shear. Areas of the hysteresis loops indicated that pastes with fibers had anti-thixotropic or mixed thixotropic/anti-thixotropic character. The greatest areas of the anti-thixotropy hysteresis loops were characteristic for WPS, while its mixtures with AF and OF caused a decrease in the value of these areas. It can indicate that starch-fiber blends were more stable during shearing. Fiber-type and starch concentration strongly affected the textural parameters of the starch-fiber gels.

Changes in Antioxidant Activity, Profile, and Content of Polyphenols and Tocopherols in Common Hazel Seed (Corylus avellana L.) Depending on Variety and Harvest Date.

The aim of the study was to evaluate the influence of variety and the date of harvest of hazelnut seeds on their antioxidant potential and the profile and content of polyphenols and tocopherols. The research material included the hazelnut seeds of six varieties, harvested from July to September at equal 30-day intervals. Hazelnuts were analyzed for total fat content and antioxidant properties, whereby UPLC-PDA-ESI-MS analysis was used to determine the profile and content of polyphenols, and the HPLC method to determine the content of tocopherols. It was found that the content of fat and tocopherols in nuts increased with the ripening of the nuts. The highest fat content was found in walnut seeds of the Katalonski variety (September) and tocopherols in walnut seeds of the Olbrzym z Halle variety (177.67 mg/kg d.m.). In turn, antioxidant properties and total polyphenols content decreased with the later harvest date. The strongest antioxidant potential was found in the case of Cosford nuts harvested in July (66.93 mmol TE/100 g d.m.). These nuts were also characterized by the highest total polyphenol content (1704.9 mg/100 g d.m.). UPLC-MS analysis allowed the identification of 15 polyphenolic compounds such as phenolic acids, catechins and ellagic acid hexoside in nut seeds.

Impact of the Degree of Maturity of Walnuts (Juglans regia L.) and Their Variety on the Antioxidant Potential and the Content of Tocopherols and Polyphenols.

The aim of the study was to characterize the antioxidant properties; establish the profile of polyphenolic compounds and evaluate the content of tocopherols in walnuts of three varieties (Leopold; Apollo; Resovia) differing in the degree of maturity (harvest date). The profile of polyphenolic compounds was established by UPLC-PDA-ESI-MS. The content of tocopherols was determined by HPLC-FLD. It was found that the content of dry matter and fat increased and the antioxidant properties decreased with the maturation of nuts. Walnuts of the Leopold cultivar harvested in July exhibited the highest content of total polyphenol (2149.08 mg/100 g dry mass). In their polyphenolic profile; 26 compounds were identified; mainly belonging to the class of ellagitannins. The polyphenolic content decreased with the maturation of nuts. The total content of tocopherols in the tested nuts increased with ripening and ranged from 1.76 mg/100g (Apollo VII) to 18.30 mg/100g (Resovia IX).

Culinary-Medicinal Mushroom Products as a Potential Source of Vitamin D.

The incidence of vitamin D deficiency has increased in recent years, mainly in Europe. The consumption of processed mushrooms may play an important role in preventing diseases associated with vitamin D deficiency. We determined the effects of 2 kinds of freezing (blast, cryogenic), canning (mild and strong brine), and drying (air-drying, freeze-drying) on the retention of vitamin D2 and ergosterol in Agaricus bisporus. Fresh and processed A. bisporus mushrooms can be a good dietary source of vitamin D2. After 12 months of storage, canned mushrooms retained the largest amount of vitamin D2 and ergosterol, whereas the smallest amount was retained in dried mushrooms. Cryogenic freezing resulted in higher levels of vitamin D2, whereas ergosterol levels were higher using air-blast freezing. The drying method had a significant effect only on ergosterol levels, which were higher in the case of freeze-drying. Room temperature gave the best results for storing dried mushrooms. In canned mushrooms, the type of brine had an effect only on levels of vitamin D2; retention was higher using the strong brine. Retention of vitamin D2 was higher at cool temperatures, whereas room temperature resulted in higher retention of ergosterol in the canned products.

Maltodextrins from chemically modified starches. Selected physicochemical properties.

The aim of this work was to evaluate the effect of chemical modification of starch (cross-linking and/or stabilisation) on selected rheological and functional properties of maltodextrins of dextrose equivalent of 6, 11 and 16. It was found that values of glass transition temperatures were decreasing with dextrose equivalent of maltodextrin. The highest values of glass transition temperature (TG) were determined for maltodextrin of DE 6-obtained from distarch phosphate and acetylated distarch phosphate. Increase in DE value of maltodextrin was also accompanied by decrease and increase in values of intrinsic viscosity and the critical concentration, respectively; however, there was no significant effect of kind of chemical modification of starch on the values of these parameters. Maltodextrin solutions at concentrations of from 10 to 70 % exhibited Newtonian flow behaviour. In the case of 50% solutions of maltodextrins of DE 6 the highest viscosity was produced by maltodextrin from native potato starch, while the lowest one by maltodextrin from acetylated starch. On the other hand, among the maltodextrin of DE 11 this one produced from acetylated starch showed the highest viscosity. All the maltodextrins exhibited surfactant properties in a water-air system, with the strongest effect observed for maltodextrins produced from double chemically modified starches and from acetylated starch. The surface activity was increasing with increasing of the DE value of maltodextrin. Moreover, values of surface tension were decreasing with increasing in maltodextrin concentration in the system.

Composition and antioxidant properties of wild mushrooms Boletus edulis and Xerocomus badius prepared for consumption.

Wild edible mushrooms Boletus edulis and Xerocomus badius were prepared for consumption by braising with 10 % canola oil (half of the batch was blanched prior to braising). Fresh X.badius had comparable to B.edulis amounts of proximate components and higher levels of most B-group vitamins and antioxidants. Analyzed mushrooms prepared for consumption fulfilled 7-14 % RDA of vitamin B1 for healthy adults and 15-35, 18-37 and 1 % RDA of B2, B3 and B3 respectively. Prepared for consumption mushrooms were rich in antioxidants containing in 100 g dry weight 164,601 mg total polyphenols, 19-87 mg total flavonoids, 22.1-27.4 mg L-ascorbic acid, 0.531-1.031 mg ß-carotene, 0.325-0.456 mg lycopene and 38.64-44.49 mg total tocopherols and presented high antioxidant activity against ABTS (4.9-36.5 mmol TE), against DPPH (7.8-21.3 mmol TE) and in FRAP assay (15.0-28.1 mmol Fe(2+)). Mushrooms prepared for consumption with blanching prior to culinary treatment showed lower antioxidant properties and vitamin content in comparison to mushrooms braised raw.

Characteristics of physico-chemical properties of bilberry (Vaccinium myrtillus L.) jams with added herbs.

Low-sugar bilberry jams without added herbs and those with added mentha (1 %) and lemon balm (1 %) were examined for levels of selected physico-chemical indicators, antioxidant activity, colour and texture. Jams were obtained by two methods: cooked in an open pan and cooked in a vacuum evaporator. 100 g fresh mass contained 0.076-0.481 mg HMF, 5.8-7.1 mg vitamin C, 176-232 mg total polyphenols, 122-156 mg total flavonoids, 73-96 mg total anthocyanins, with antioxidant activity per 1 g of 405-575 µM Trolox (ABTS), 71-89 µM Trolox (DPPH) and 120-176 µM Fe(2+) (FRAP). Jams cooked in a vacuum evaporator had higher levels of the indicators examined, better colour and worse texture. Jams with added herbs generally showed higher levels of all indicators, but their colour and texture were slightly worse. Storing jams for 8 months caused a reduction in antioxidant constituents of 7-20 % along with a deterioration of colour and texture.

Effect of microwave blanching on the quality of frozen Agaricus bisporus.

The aim of this work was to determine the effect of microwave blanching on the levels of selected quality parameters in frozen Agaricus bisporus. Before freezing, mushrooms underwent one of the following treatments: blanching in water; blanching in a solution of sodium metabisulphite and citric acid; microwaving for 5 min; and combined blanching (first in water, then in a microwave oven). Products were freeze stored for 8 months at -25 ℃. Frozen storage resulted in decreased levels of vitamin B1, total polyphenols and antioxidant activity of 10-49%, as well as an increase in polyphenol oxidase activity compared with products immediately after freezing. The values for most colour parameters and whiteness intensity decreased, while cream, yellow, brown and grey saturation increased. There was a considerable deterioration in sensory quality, particularly colour. Microwave-blanched products had significantly higher dry matter, ash, vitamin B1 and B2 content than the remaining products as well as half the polyphenol oxidase activity. Total polyphenols and antioxidant activity were highest in the product blanched in the sodium metabisulphite solution, followed by the microwave-blanched product. Compared with the product blanched using sodium metabisulphite, microwave-blanched mushrooms showed slightly greater darkening but were superior in flavour and aroma.

Influence of the Culinary Treatment on the Quality of Lactarius deliciosus.

The influence of culinary treatment on the nutritional value and quality of Lactarius deliciosus was established. Mushrooms: unblanched (I), blanched (II), and unblanched with onion and spices (III), were fried in oil for 10 min. Fried mushrooms were assessed before storage as well as after 48 h in storage at 20 °C, and after 48 and 96 h in storage at 4 °C. Frying increased the dry weight, protein, fat, ash, total carbohydrate, total polyphenol, and total flavonoid content, as well as the caloric value of the mushrooms. In addition, frying decreased the antioxidant activity, color parameters (a*, h*), and texture. The most significant changes due to culinary treatment and storage were observed in type II product. Microbiological analysis of the samples after a 48 h storage period at 20 °C revealed the total viable count over 106 and contamination with lactic acid bacteria. Fried mushrooms stored at 4 °C for 96 h were free from microorganisms.

Baseline sensitivity to proquinazid in Blumeria graminis f. sp. tritici and Erysiphe necator and cross-resistance with other fungicides.

BACKGROUND: Proquinazid is a new quinazolinone fungicide from DuPont registered in most European countries for powdery mildew control in cereals and vines. The aim of this paper is to present baseline sensitivity data in populations of Blumeria graminis f. sp. tritici EM Marchal and Erysiphe necator (Schw) Burr as well as results from cross-resistance studies with other fungicides. RESULTS: Proquinazid exhibited a high intrinsic activity on B. graminis f. sp. tritici isolates at rates ranging from 0.000078 to 0.02 mg L(-1). Erysiphe necator isolates were comparatively less sensitive to proquinazid, with EC(50) values ranging from 0.001 to 0.3 mg L(-1). Proquinazid controlled equally well B. graminis f. sp. tritici isolates sensitive and resistant or less sensitive to tebuconazole, fenpropimorph, fenpropidin, cyprodinil and kresoxim-methyl. A positive correlation (r = 0.617) between quinoxyfen and proquinazid sensitivities was found among 51 B. graminis f. sp. tritici isolates. Quinoxyfen-resistant B. graminis f. sp. tritici isolates were slightly less sensitive to proquinazid than the quinoxyfen-sensitive isolates; however, proquinazid remained much more active than quinoxyfen on these isolates. A stronger sensitivity relationship (r = 0.874) between proquinazid and quinoxyfen was found among 65 E. necator isolates tested in a leaf disc assay. The sensitivity values for proquinazid were significantly lower than those for quinoxyfen, confirming the higher intrinsic activity of proquinazid on both pathogens. CONCLUSION: Given the history of resistance development in powdery mildew and the observed sensitivity relationship with quinoxyfen, specifically in E. necator, we conclude that the risk of resistance developing to proquinazid might be influenced by the use of quinoxyfen. Based on these results, the authors recommend that proquinazid and quinoxyfen be managed together for resistance management.

Effect of dose rate and mixtures of fungicides on selection for QoI resistance in populations of Plasmopara viticola.

Resistance to QoI fungicides (strobilurins, famoxadone and fenamidone) in populations of Plasmopara viticola (Berk & Curt) Berlese & de Toni developed soon after their introduction in France and Italy. Current resistance management strategies include limitation of the number of applications, use of mixtures and alternation of fungicides with different modes of action. The selection pressure resulting from QoI fungicides applied alone or in mixtures with non-QoI fungicides was investigated in whole plant experiments under controlled conditions. QoI-resistant populations of P. viticola gradually reverted to full sensitivity following consecutive transfers to untreated plants, suggesting that resistant phenotypes were less competitive than sensitive ones. When cycled on QoI-treated plants, reduction in sensitivity was greater for the QoI fungicide which had greater intrinsic activity on P. viticola. Sensitivity decreased at each subsequent cycle, resulting in almost full resistance after four generations. Mixture experiments indicated that selection pressure was affected most by the dose of the QoI fungicide and the nature of the partner fungicide. Folpet delayed selection pressure most effectively when it was associated with famoxadone or azoxystrobin. Mancozeb was least effective at reducing the rate of selection compared with the QoI alone, and fosetyl-aluminium was intermediate. Higher rates of selection were recorded when the dose of the QoI fungicide, solo or in a mixture, was increased from 1 to 4 microg ml(-1). Increasing the dose of the non-QoI partner fungicide in the mixture from 10 to 30 microg ml(-1) resulted in reduced selection pressure. These results suggest that the choice of the fungicide partner and its dosage in the mixture can significantly affect the success of QoI resistance management strategies under practical conditions.