Polyphenol Oxidase from Malatya Apricot (<i>Prunus </i><i>armeniaca </i>L.)

Arslan, Oktay; Temur, and Arzu; Tozlu, İsrafil

doi:10.1021/jf970599v

Cited by 54 publications

(45 citation statements)

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“…Quinones also lead to polymerisation and condensation reactions between proteins and polyphenols, because they are very reactive compounds that strongly interact with other molecules, leading to a large variety of dark-coloured compounds (Dogan et al 2009). Because of the importance of this reaction in the food industry, PPO has been intensively studied in several plant tissues such as aubergine (Dogan et al 2002), Origanum (Dogan et al 2005a), apricot (Arslan et al 1998), Thymus species (Dogan et al 2003a,b), Salvia types (Gundogmaz et al, 2003), Ocimum basillicum L. (Dogan et al 2005b), Thymbra (Dogan et al 2006), Cynara scolymus L. (Dogan et al 2005c), DeChaunac grapes (Lee et al 1983), Allium sp. (Arslan et al 1997), Amasya apple (Oktay et al 1995), Ferula sp.…”

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confidence: 99%

Characterisation of polyphenol oxidase from Melissa officinalis L. subsp. officinalis (lemon balm)

Doğan¹,

Ayyıldız²,

Doğan³

et al. 2013

Czech J. Food Sci.

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Polyphenol oxidase (PPO) from Melissa officinalis L. subsp. officinalis (lemon balm) was partially purified by ammonium sulphate precipitation and dialysis; and then it was characterised in detail in terms of pH and temperature optima, thermal stability, kinetic parameters, and inhibition properties. Based on experimental results, it was found out that (i) the optimum pH and temperature values of PPO were 6.5, 4.0, and 8.5 and 40, 50, and 60°C for catechol, 4-methylcatechol and pyrogallol substrates, respectively; (ii) the best substrate was pyrogallol due to the highest V max /K m value, followed by catechol and 4-methylcatechol; (iii) enzyme activity decreased due to heat denaturation of the enzyme with increasing temperature and inactivation time for all substrates; (vi) gallic acid and l-glutamic acid did not inhibit PPO; and (v) the most effective inhibitor was glutathione. Furthermore, the phenolic and protein contents of lemon balm extract were also determined according to the Folin-Ciocalteu and Bradford methods, respectively.

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confidence: 99%

Characterisation of polyphenol oxidase from Melissa officinalis L. subsp. officinalis (lemon balm)

Doğan¹,

Ayyıldız²,

Doğan³

et al. 2013

Czech J. Food Sci.

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Section: Univariate Studiesmentioning

confidence: 96%

“…However, the optimum pH has been found to vary with the enzymatic source and the substrate over a relatively wide range of values, 22 including in alkaline medium. 21 The best phosphate buffer concentration was 0.10 mol L -1 , as indicated in Figure 2. In order to prevent undesirable reactions between the natural phenols and PPO, quantitative extraction of plant phenols can be made using water-insoluble PVP, which can extract biophenols by a well-postulated hydrogen bonding of the ionizable hydrogens of the plant phenol to oxygens of the polyvinylpyrrolidone.…”

Section: Univariate Studiesmentioning

confidence: 96%

“…3,4 Assay of PPO activity Enzyme activity was determined measuring the increase in absorbance at 410 nm owing to the formation of the respective quinone for each substrate studied. 3,4,7,21 Blank tests containing only 3.0 mL of substrate solution or the buffer solution did not provide any catalytic effect. A typical reaction 3,4,7,8 was carried out by mixing of 2.8 mL of the selected substrate and 0.20 mL of the crude extract in a quartz cuvette.…”

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confidence: 91%

“…As it can be noted, catechol presented the best quantitative quinone formation, as also indicated in other investigations. 19,21 In this way, Jackfruit crude extract presented excellent selectivity for catechol and this substrate was used in both the univariate and factorial studies.The pH dependence study for catecholase activity is presented in Figure 1. The pH profile was determined between 4.0 to 8.0.…”

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Factorial Design Evaluation of Some Experimental Factors for Phenols Oxidation using Crude Extracts from Jackfruit (Artocarpus integrifolia)

Cestari

Vieira

Nascimento

et al. 2002

J. Braz. Chem. Soc.

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Este estudo apresenta algumas informações adicionais sobre a utilização alternativa do extrato bruto da jaca, em reações de oxidação seletivas de fenóis. Foram avaliados os substratos catecol, o-, me p-cresóis e pirogalol. Estudaram-se também os efeitos do pH, da concentração do tampão fosfato, bem como a utilização de alguns tipos de agentes extratores de biofenóis. Utilizando-se o procedimento convencional univariado, a atividade enzimática foi maior com o substrato catecol, em tampão fosfato pH 5,0, de concentração 0,10 mol L -1 e agente comercial extrator de fenóis Polyclar SB-100 â . Usando-se um planejamento fatorial, do tipo 2 3 , constatou-se que os melhores desempenhos catalíticos foram em pH 5,0 e concentração de tampão 0,050 mol L -1 , para o substrato catecol. A variação no tipo de extrator não mostrou importância estatística. Pelo método multivariado, obtiveram-se os melhores resultados para a oxidação seletiva do catecol. Assim, conclui-se que para aumentar o desempenho catalítico do extrato, deve-se utilizar preferencialmente a metodologia multivariada.This study presents some additional information on the alternative utilization of Jackfruit crude extracts in selective phenol oxidation reactions, using catechol and the o-, m-e p-cresols and pyrogallol substracts. The effects of pH, concentration of phosphate buffer and kinds of natural phenol extractors are evaluated. By using the conventional univariate procedure, the best enzymatic activities were obtained with the catechol substract, phosphate buffer (pH 5.0) at a concentration 0.10 mol L -1 , and the commercial polymer Polyclar SB-100 â as natural phenol extractor. Using a full 2 3 factorial design the best catalytic results were obtained by employing phosphate buffer at pH 5.0 and it 0.050 mol L -1 . However, the kind of phenol extractor was not statistically important. The best results for selective catechol oxidation were obtained by using the multivariate technique. In this way, the multivariate methodology is indicated to increase the performance of the crude extract in the selective oxidation reactions.Keywords: homogeneous enzymatic catalysis, jackfruit, phenol oxidations, factorial designs IntroductionRecently, an increasing trend has been observed in the use of new biocatalytic materials in place of pure enzymes, for the development of several different research lines, especially those related to the development of biosensors 1 and enzyme-catalyzed methods of analysis. 2 The use of such materials offers some advantages with regard to those procedures based on the use of pure and isolated enzymes, especially by providing a better lifetime and lower cost. 3,4 Natural and undesirable browning reactions, using atmospheric oxygen as oxidant, occur by the catalysis of, mainly, the enzyme polyphenol oxidase (PPO). 3-5 PPO is a copper-containing oxidase having catecholase and/or cresolase activity. PPO catalyses o-hydroxylation of monophenols to give o-diphenols (cresolase activity) and o-diphenols to o-quinones (catecholase activity). For P...

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Increase in antioxidant activity of brined olives (Carolea cv.) thermally treated in different packaging types

Piscopo

Bruno

Zappia

et al. 2015

Euro J Lipid Sci & Tech

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This work was aimed to study the effect of a thermal processing on brined olives (and their covering liquids) packaged in different types of containers (glass jar with two volumes and plastic pouches made of two materials). The results show an increase of antioxidant activity of all pasteurized olives because of the melanoidin formation in pulp after processing with no differences among materials and sizes of packaging. In this study, glass packaging involved lower depletion of total polyphenol content and better preservation of the a-tocopherol content in olive pulp than plastic pouches during the processing. The olives packaged in PA/PE showed higher content of antioxidant compounds than the olives processed in OPA/PP pouches.Practical application: Practical application for the study entitled "Increase in antioxidant activity of brined olives (Carolea cv.) thermally treated in different packaging types" regards the study of chemical changes on olives in different containers. Therefore in food industry the positive effect of heat and the right packaging form could be useful for preservation of olives and also enhancing of their functional properties. The results of this work showed an increased antioxidant activity in brined olives thermally treated, due to the melanoidin formation.

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Polyphenol Oxidase from Malatya Apricot (Prunus armeniaca L.)

Cited by 54 publications

References 10 publications

Characterisation of polyphenol oxidase from Melissa officinalis L. subsp. officinalis (lemon balm)

Characterisation of polyphenol oxidase from Melissa officinalis L. subsp. officinalis (lemon balm)

Factorial Design Evaluation of Some Experimental Factors for Phenols Oxidation using Crude Extracts from Jackfruit (Artocarpus integrifolia)

Increase in antioxidant activity of brined olives (Carolea cv.) thermally treated in different packaging types

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