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1

Polyphenol oxidase from Gliocladium virens

100%

Halasinska A. G., Trzcinska M., Sieliwanowicz B.

Polish Journal of Food and Nutrition Sciences

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2001

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tom 10

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nr 1

Polyphenol oxidase (PPO) was obtained after 48-h cultivation of G. virens in modified Czapek-Dox liquid medium with 2% starch as carbon source. The optimum pH and temperature of PPO was 6.0 and 35°C, respectively. At 30°C, the enzyme activity remained unchanged for 6 h, whereas at 35°C and 40°C it lost half of the activity after 3.5 h and 20 min, respectively. The molecular weight of PPO, determined on a basis of native electrophoresis, was 50 kDa. The enzyme showed the greatest affinity towards syringaldazine, also oxidising chlorogenic acid, gallic acid, (-)epicatechin, ( + )catechin, catechol, and phloridzin. PPO from G. virens oxidised the phenolic compounds present in apple juice and ascorbic acid was strong inhibitor of this reaction. The anti-oxidant properties of apple juice were shown to decrease to a small degree and only temporarily due to the oxidation by PPO from G. virens.

2

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Phytoremediation of quizalofop-ethyl contaminated soil using Sesbania sesabn L.

86%

Mahakavi T., Baskaran L., Bakiyaraj R., Mycin R.

International Letters of Natural Sciences

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2015

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tom 44

In this field experiments, sandy loam soil was treated with different concentration of herbicide (Quizalofop-ethyl) 0.5, 1.0, 1.5 and 2 per cent. Sesbania sesban L. seeds were sown in all treated soil. The germination percentage, morphological and enzymes activities were measured after 20, 40 and 120 days. The results indicate that the germination per cent, morphological parameters were increased in control then it was gradually decreased with increasing the herbicide concentration. The enzymes like catalase and peroxidase activity were increased in control then it was decreased with increasing the concentration. Whereas the polyphenoloxidase acticity was lower in control and it was increased with increasing the herbicides concentration. Hence, after 120 days plants were harvested and the plant powder was analyzed for absorption of herbicide by plant with the help of Gas chromatography mass spectrum (GCMS). The obtained data showed that herbicide absorption was concerned in quiazalofop-ethyl treated plant when compared to control. This study expose that herbicide reduced by Sesbania sesban L.

3

Polyphenolic compounds of plums [Prunus domestica]

86%

Los J., Wilska-Jeszka J., Pawlak M.

Polish Journal of Food and Nutrition Sciences

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2000

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tom 09/50

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nr 1

The total polyphenols content in investigated plums, as well as anthocyanins and flavanols, was rather low (160-300 mg/100 g, 1833 mg/100 g and 914 mg/100 g of fruits, respectively). (+) Catechin occurring in quantities from 1.3 to 3.9 mg/100 g was found to be a dominant compound representing biologically active monomers and dimers of flavanols. The highest quantities of hydroxycinnamic acids, especially neochlorogenic one, (46-85 mg/100 g) are found in all plum varieties. The main anthocyanin pigments of plums are cyanidin-3-glucoside and cyanidine-3- rutinoside; they make up 42 to 62% of the total anthocyanins. All investigated plum varieties show high polyphenoloxidase activity but there are substantial differences between particular varieties ranging from 3200 to 17200 U/g.

4

Some characteristics of active and latent monophenolase of mushroom polyphenol oxidase

72%

Czapski J.

Acta Agrobotanica

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1998

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tom 51

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nr 1-2

33-41

Latent form of monophenolase of mushroom polyphenol oxidase (PPO) was activated by 0,1 % sodium dodecyl sulfate (SDS). The addition of increasing concentrations of 4-methylcatechol diminished lag period of active and total monophenolase activity, measured using p-cresol with L-proline as a substrate. Changes of lag period were described by equation of one phase exponential decay when concentration of substrate varied from 1 to 10 mM. Affinity (1/Km) toward substrate of latent monophenolase was over two times higher than that of the active form, while the maximum velocity (Vmax) was two times lower. The catalytic power (Vmax/Km) of both forms of monophenolase were almost equal. Electrophoretic analysis followed by scanning technique of the gels was used. Absorbancy of spots, determined from computer image of isoenzyme bands pattern allowed for qualitative and quantitative estimation of electrophoregrams. Presence of one additional clearly defined slow migrating isoenzyme for SDS activated monophenolase differed in this respect active (2 bands) and total (3 bands) forms of monophenolase. Key words: Agaricus bisporus; mushroom; latent and active monophenolase; lag period; enzyme kinetic; electrophoretic isoenzyme pattern.

5

The mechanism of azide activation of polyphenol oxidase II from tobacco

72%

Shi C., Liu Q., Dai Y., Xie Y., Xu X.

Acta Biochimica Polonica

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2002

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tom 49

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nr 4

So far, azide has been consistently reported to act as an inhibitor of metal enzymes, especially copper proteins. The present work shows that azide can also act as an activator of polyphenol oxidase II (PPO II) from tobacco leaves. From the square-wave voltammetry of native PPO II, peroxide-PPO II complex and azide-PPO II complex, the reduction of nitro blue tetrazolium by the enzymes and activation of PPO II by peroxide it follows that the binding of azide to PPO II induces the formation of CuO2 2-Cu in the active site of PPO II from CuO2 -Cu in native PPO II. The reason for azide acting as an activator can be attributed to azide complexing with PPO II, thus inducing the formation of CuO2 2-Cu, which is the active site of the peroxide-PPO II complex in which peroxide plays the role of activator.

6

Probing behaviour and enzymatic defence of the grain aphid against cereal phenolics

72%

Urbanska A., Leszczynski B., Tjallingii W. F., Matok H.

Electronic Journal of Polish Agricultural Universities. Series Biology

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2002

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tom 05

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nr 2

Probing behaviour of the grain aphid, Sitobion avenae (F.) on sucrose-agarose gels containing o-dihydroxyphenolics was examined using the EPG (electrical penetration graphs) technique. The aphids on diets containing certain o-dihydroxyphenols differed in the mean number of probes and duration of first probe and stylet pathways.

7

Polifenolooksydaza i beta-glukozydaza w wybranych owocach jagodowych

58%

Wlazly A., Targonski Z.

Żywność Nauka Technologia Jakość. Suplement

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2000

|

tom 07

|

nr 3

122-132

Oznaczano aktywność polifenolooksydazy (PPO) i ß-glukozydazay w owocach takich, jak: truskawka, malina, porzeczka czerwona i porzeczka czarna. Z każdego rodzaju owocu wybrano 3 odmiany. Do oznaczenia stosowano metody spektrofotometryczne. Substrátem w reakcji enzymatycznej były katechol dla PPO i p-nitrofenolo-ß-D-glukozyd dla ß-glukozydazy. Zbadano również wpływ pH i temperatury na aktywność tych enzymów oraz ich termiczną inaktywację. Aktywność PPO stwierdzono jedynie w truskawkach odmiany Senga-Sengana i Ducat, a aktywność ß-glukozydazay w truskawkach Senga-Sengana, Ducat, Marmolada i malinach Canby, Beskid, Seedling. Optymalne warunki dla działania PPO były następujące: pH 4,5 i temp.45°C, a dla ß-glukozydazay pH w zakresie 5,0-5,5 i temp. od 40°C do 50°C w zależności od pochodzenia enzymu.

8

Genetic mapping of polyphenol oxidase in tetraploid wheat

58%

Simeone R., Pasqualone A., Clodoveo M. L., Blanco A.

Cellular and Molecular Biology Letters

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2002

|

tom 07

|

nr 2B

Pasta colour is one of the main factors inﬂuencing pasta quality. It is the product of a desirable yellow component, an undesirable brown component and, under some drying conditions, a red component. The brown colour depends on enzymatic and chemical factors. Polyphenol oxidase (PPO; E.C. 1.14.18.1) is one of the enzymatic factors. It is mainly localised in the peripheral part of the wheat kernel, and is involved in the oxidation of endogenous wheat phenolic compounds resulting in the production of highly coloured products. Therefore, a knowledge of the genetic control of PPO activity could enable the developing of better strategies in breeding programs to reduce pasta darkening. The aim of this study was to map the gene(s) affecting PPO activity using a set of recombinant inbred (RI) lines, derived from a cross between Triticum turgidum L. var. durum cultivar Messapia and the accession MG4343 of Triticum turgidum L. var. dicoccoides. After performing linkage analysis, the gene for high PPO activity was mapped on the long arm of the chromosome 2A and its characteristic was found highly associated to the RFLP marker Xutv1427-2A, with a value of LOD equal to 29.84. The identification of molecular markers linked to loci controlling the PPO activity may potentially accelerate wheat breeding since the selection of plants can be carried out by genotype rather than phenotype.

9

Quality changes in lettuce heads stored in a controlled atmosphere. II. Phenolic metabolism and ethylene evolution

58%

Leja M., Mareczek A., Rozek S.

Folia Horticulturae

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1996

|

tom 08

|

nr 2

10

The effect of fertilization with different forms of nitrogen on greenhouse lettuce quality and its changes during storage. III. Phenolic metabolism

58%

Leja M., Rozek S., Myczkowski J.

Folia Horticulturae

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1994

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tom 06

|

nr 1

11

The effect of fertilization with nitrate and urea forms of nitrogen on quality and storage ability of lettuce grown in a foil tunnel. III. Phenolic metabolism

58%

Leja M., Rozek S., Myczkowski J.

Folia Horticulturae

|

1995

|

tom 07

|

nr 1

12

Enzymatic oxidation of polyphenols in fruit products and model solutions

58%

Los J., Wilska-Jeszka J., Pawlak M.

Polish Journal of Food and Nutrition Sciences

|

1996

|

tom 05

|

nr 1

Polyphenoloxidase (PPO) activity, total polyphenols and flavanols contents in various fruit species were investigated in relation to their susceptibility to browning processes. Marked differences in substrate affinities of PPO preparations from apples and pears were found. The rate of browning of (+)catechin solutions was higher for the apple PPO than for the pear enzyme. In contrast, the pear PPO catalysed an oxidation of (-)epicatechin to higher extent. Phenolic acids, i.e. chlorogenic and caffeic, were oxidised more slowly than catechins. It was observed that in pulps from fruits rich in polyphenoloxidase, e.g. from apples and pears, stored at room temperature, the browning process was accompanied by considerable losses of flavanols (40% after 1 h). In strawberry pulps exhibiting a low PPO activity no decrease of flavanols was observed under the same conditions.

13

Metabolic changes in certain biochemical compounds in short-term stored carrot root slices

58%

Leja M., Mareczek A., Rozek S.

Folia Horticulturae

|

1995

|

tom 07

|

nr 2

14

Effect of mechanical damage of greenhouse lettuce on some biochemical processes ossurring in it during storage

58%

Leja M., Mareczek A.

Folia Horticulturae

|

1995

|

tom 07

|

nr 1

15

Endogenous phenolic contents, peroxidase and polyphenoloxidase activities in date palm [Phoenix dactylifera L.] offshoots related to rooting ability

58%

Qaddoury A., Amssa M.

Acta Physiologiae Plantarum

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2003

|

tom 25

|

nr 4

16

Activity of polyphenoloxidase in the ears of spring wheat and triticale infested by grain aphid [Sitobion avenae F.]

58%

Chrzanowski G., Ciepiela A. P., Sprawka I., Sempruch C., Sytykiewicz H., Czerniewicz P.

Electronic Journal of Polish Agricultural Universities. Series Biology

|

2003

|

tom 06

|

nr 2

Polyphenoloxidase (PPO) plays an important role in plant resistance to insects, and in the detoxication of phenolic compounds taken in the nutrient components. Activity of PPO was examined in the ears of spring wheat and triticale. Extraction of enzymatic protein was carried out from acetone powder with the use of 0.05M phosphoric buffer of pH 7.4. The cultivars of spring wheat have possessed higher activity of PPO than cultivars of triticale. Feeding of the grain aphid has reduced this enzyme activity in the all analysed species and cultivars.

17

Effect of chitosan coating on shelf-life and quality of fresh-cut mushroom

51%

Eissa H. A. A.

Polish Journal of Food and Nutrition Sciences

|

2008

|

tom 58

|

nr 1

The effect of chitosan coating in fresh-cut mushroom preservation, including microbiological, enzyme activities, colour characteristics and chemical quality attributes, was examined. However, application of chitosan coating to enzyme activity control and quality maintenance of fresh-cut mushroom was investigated. Fresh-cut mushroom were treated with aqueous solution containing 5, 10 and 20 g of chitosan/1 L, placed in polyethylene bags, and then stored at 4°C. Changes in total phenolic content, and cellulase (CEL), total amylase, α and β amylase, laccase (LAC), phenylalanine ammonia lyase (PAL), peroxidase (POD), catalase (CAT) and polyphenoloxidase (PPO) enzymes activities were measured. Applications of chitosan coating delayed discoloration associated with reduced enzyme activities of LAC, PAL, POD, CAT and PPO as well as lowered total phenolic content. Also, it slowed down texture changes associated with reduced enzyme activities of CEL, total amylase and α-amylase. Results showed that increasing the concentration of chitosan coating resulted in higher contents of total soluble solids (TSS), total acidity and TSS/T acid ratio of fresh-cut mushroom. In mushroom, during storage at 4°C for 15 days, 20 g/kg chitosan coating inhibited the growth of total bacteria, yeasts and moulds counts. Chitosan also had a good effect on the evolution of the colour characteristics and parameters (C* and BI) of fresh-cut mushroom during storage at 4°C. The results showed that increasing the concentration of chitosan coating enhanced the beneficial effects of chitosan on extended shelf-life and maintained quality of fresh-cut mushroom.

18

Physiological role of phenolics

44%

Plazek A., Dubert F.

Zeszyty Problemowe Postępów Nauk Rolniczych

|

2008

|

tom 524

Phenylpropanoids are a numerous group of the secondary metabolites. The pathway of phenolic biosynthesis is induced in plants under the treatment of various unfavorable factors. Phenylpropanoid compounds act twofold: they can be toxic for plant, inhibiting their growth and development, and, on the other side, they protect plants from stress effect. In the paper the most important phenolics, their properties and influence on plant metabolism, the typical reactions and application in pharmacy were discussed. The molecular explanation of oxidation reactions, lignin polymerization, tannin condensation, UV absorbtion and decomposition and the production of reactive oxygen species were demonstrated. In plant physiology phenylpropanoid compounds are grouped into simple and composed phenylpropanoids. Simple pheylpropanoid compounds involve mainly phenolic acids and alcohols, vanilin and coumarins. Chlorogenic acid demonstrates antibiotic properties, while salicylic acid (SA) is a plant growth and development regulator, playing also a signal role in plant defence response to numerous stresses. SA initiates synthesis of PR (pathogenesis-related) proteins, hydrogen peroxide production and controls systemic acquired resistance (SAR). Phenolic alcohols polymerize to lignin, which strengths cell wall and builds natural barrier against pathogen attack. Compounds like vanilin, strong aromatic, attract insects and are used in cosmetic and food industry. Coumarins show phototoxic effect and also demonstrate a growth inhibitor action. Composed phenylpropanoids involve tannins, flavonoids and isoflavonoids. Tannins protect plants from pathogens and deter preying insects. Flavonoids are pigments of flowers and leaves, and can protect cell structures and organic compounds from cold, UV radiation and free radicals. Isoflavonoids are characterized mainly by insecticide feature. Many isoflavonoids belong to phytoalexins, specific compounds synthesized within defence mechanism against stresses. They inhibit fungal spore germination and act osmotically to penetrating hyphae. Moreover, these compounds may imitate steroid molecules joining to specific steroid receptors disturbing numerous metabolic processes. Among the best known phytoalexins pisatin, phaseolin and medicarpin are mentioned. Phenylpropanoids also play an allelopathic role secreted by roots into soil, and inhibiting germinating and growth of other plants.

Ograniczanie wyników

Polyphenol oxidase from Gliocladium virens

Phytoremediation of quizalofop-ethyl contaminated soil using Sesbania sesabn L.

Polyphenolic compounds of plums [Prunus domestica]

Some characteristics of active and latent monophenolase of mushroom polyphenol oxidase

The mechanism of azide activation of polyphenol oxidase II from tobacco

Probing behaviour and enzymatic defence of the grain aphid against cereal phenolics

Polifenolooksydaza i beta-glukozydaza w wybranych owocach jagodowych

Genetic mapping of polyphenol oxidase in tetraploid wheat

Quality changes in lettuce heads stored in a controlled atmosphere. II. Phenolic metabolism and ethylene evolution

The effect of fertilization with different forms of nitrogen on greenhouse lettuce quality and its changes during storage. III. Phenolic metabolism

The effect of fertilization with nitrate and urea forms of nitrogen on quality and storage ability of lettuce grown in a foil tunnel. III. Phenolic metabolism

Enzymatic oxidation of polyphenols in fruit products and model solutions

Metabolic changes in certain biochemical compounds in short-term stored carrot root slices

Effect of mechanical damage of greenhouse lettuce on some biochemical processes ossurring in it during storage

Endogenous phenolic contents, peroxidase and polyphenoloxidase activities in date palm [Phoenix dactylifera L.] offshoots related to rooting ability

Activity of polyphenoloxidase in the ears of spring wheat and triticale infested by grain aphid [Sitobion avenae F.]

Effect of chitosan coating on shelf-life and quality of fresh-cut mushroom

Physiological role of phenolics