Effects of melatonin treatment on the enzymatic browning and nutritional quality of fresh-cut pear fruit

The basic study on activity of polyphenol oxidase (PPO) from purple sweet potato (PSP) and its control method was mainly carried out by spectrophotometry. The PPO activity and browning degree (BD) of PSP peel were higher than those of inner-tissue and intact sweet potatoes. The relativity between them was positive, and relativity coefficient was 0.9895. The activity of PPO extracted from sliced PSP increased initially and decreased afterwards, with the highest activity of PPO on the third day during storage. And BD increased very quickly as time went by, especially in the first three days. The relativity between PPO activity and BD was negative, and relativity coefficient was-0.8747. The result indicated that the browning of fresh-cut PSP slices during storage was mainly due to PPO in it. The composite inhibitor was optimized by the orthogonal design, and the addition of0.05% L-cysteine+0.03% phytic acid+0.3% ascorbic acid+0.3% citric acidwould markedly inhibit the enzymatic browning caused by PPO and improve the quality of fresh-cut PSP slices.

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COMBINED TECHNOLOGIES TO INHIBIT ENZYMATIC BROWNING AND PRESERVE QUALITY OF FRESH-CUT ARTICHOKE HEARTS

Acta Horticulturae ◽

10.17660/actahortic.2012.942.56 ◽

2012 ◽

pp. 385-390 ◽

Cited By ~ 1

Author(s):

P. Gómez di Marco ◽

P. Robles ◽

J. Braun ◽

F. Artés Hernández ◽

J.A. Fernández ◽

...

Keyword(s):

Enzymatic Browning ◽

Fresh Cut

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Influence of Two Different Coating Application Methods on the Maintenance of the Nutritional Quality of Fresh-Cut Melon during Storage

Applied Sciences ◽

10.3390/app11188510 ◽

2021 ◽

Vol 11 (18) ◽

pp. 8510

Author(s):

Cinzia Mannozzi ◽

Virginia Glicerina ◽

Urszula Tylewicz ◽

Juan Manuel Castagnini ◽

Giada Canali ◽

...

Keyword(s):

Nutritional Quality ◽

Microstructural Analysis ◽

Ascorbic Acid Content ◽

Microstructural Properties ◽

Total Polyphenols ◽

Coating Solution ◽

Coating Application ◽

Fresh Cut ◽

Application Methods

This study aimed at evaluating the effects of two coating application methods, spraying and dipping, on the quality of fresh-cut melons. An alginate-based coating containing both ascorbic and citric acid was applied at two concentrations (5% and 10%) with both methods on fresh-cut melon. The nutritional quality of the products was investigated during 11 days of storage at 10 °C. The suitability and adaptability of the applied coatings on the fruit were evaluated based on rheological and microstructural properties. Moisture, carotenoids, total polyphenols and ascorbic acid content were analyzed on melon samples during storage. Results showed that the coating solution applied by the dipping method and at the highest concentration (10%), allowed to better maintain some quality characteristics of fresh-cut melon, thanks also to the better coating homogeneity and higher thickness observed through microstructural analysis.

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Comparative Transcriptomic Analyses Provide Insights into the Enzymatic Browning Mechanism of Fresh-Cut Sand Pear Fruit

Horticulturae ◽

10.3390/horticulturae7110502 ◽

2021 ◽

Vol 7 (11) ◽

pp. 502

Author(s):

Jing Fan ◽

Wei Du ◽

Qi-Liang Chen ◽

Jing-Guo Zhang ◽

Xiao-Ping Yang ◽

...

Keyword(s):

Molecular Mechanisms ◽

Transcript Level ◽

Enzymatic Browning ◽

Rna Seq ◽

Pear Fruit ◽

Total Polyphenol ◽

Phenylpropanoid Biosynthesis ◽

Key Enzyme ◽

Fresh Cut ◽

High Level

Pear (Pyrus spp.) is one of the most commonly consumed temperate fruits, having considerable economic and health importance. Fresh-cut or processed pear fruits are prone to browning because of the abundant phenolic compounds; however, little is known about the molecular mechanisms underlying enzymatic browning of fresh-cut sand pear fruit. In this study, fruits of two sand pear genotypes (low browning cultivar ‘Eli No.2′ and high browning cultivar ‘Weiningdahuangli’) were used to analyze the molecular mechanism of enzymatic browning by SMRT-seq and RNA-seq. The results generated 69,122 consensus isoforms, 21,336 new transcripts, 7105 alternative splicing events, and 254 long non-coding RNAs (lncRNAs). Furthermore, five genes related to enzymatic browning were predicted to be targets of six lncRNAs, and 9930 differentially expressed genes (DEGs) were identified between two different flesh browning cultivars. Meanwhile, most DEGs (e.g., PAL, 4CL, CAD, CCR, CHS, and LAR) involved in the phenylpropanoid biosynthesis pathway were up-regulated, and the expression of PPO and POD were highly expressed in the high-browning cultivar. Interestingly, the transcript level of PbrPPO4 (Pbr000321.4) was significantly higher than other PPO and POD genes, and a high level of total polyphenol and PPO activity were observed in the high browning cultivar. We found that the expression of lncRNA PB.156.1 was significantly positively correlated with the target gene PbrPPO4 (Pbr000321.4). The results suggest that PbrPPO4 might act as a major contributor and a key enzyme encoding gene in regulating fresh-cut sand pear fruit enzymatic browning; the expression of PbrPPO4 was probably regulated by lncRNA PB.156.1. Altogether, the transcriptomic and physiological analyses expand the knowledge of sand pear flesh enzymatic browning at the molecular level and provide a foundation for germplasm resources for molecular breeding of high polyphenol and low browning cultivars in sand pears.

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Bioflavonoids of Apples: Effects of Genetic Variability, Fruit Parts and Processing

HortScience ◽

10.21273/hortsci.39.4.829d ◽

2004 ◽

Vol 39 (4) ◽

pp. 829D-829

Author(s):

Vicky W. Lee ◽

H.P. Vasantha Rupasinghe* ◽

Chung-Ja Jackson

Keyword(s):

Vitamin C ◽

Chlorogenic Acid ◽

Nutritional Quality ◽

Apple Fruit ◽

Total Phenols ◽

Apple Peel ◽

Total Antioxidant ◽

Phenolic Profiles ◽

Fresh Cut

Apples are excellent sources of dietary phenolics, in particular flavonoids and chlorogenic acid, which are potent antioxidants that may play important roles in the prevention of chronic diseases. This study investigated the major phenolics profiles of apple fruit in relation to (1) the distribution among 8 Ontario-grown cultivars, (2) the different fruit parts, and (3) the effect of processing of fresh-cuts. In addition, total antioxidant capacity (TAC) and total phenols content (TPC) were measured in apples by spectrophotometric assays. Flavonoids and chlorogenic acid were quantified using HPLC/PDA. Vitamin C was quantified using HPLC/Fluorescence. TAC, TPC and flavonoids levels were the highest in Honey Crisp and Delicious, moderate in Idared, Spartan, Granny Smith, and Cortland, and the lowest in Crispin and Empire. Apple peel contained 2 to 10-fold higher TAC, TPC and total of 10 major phenolics than that of core and flesh indicating peeling of apples during processing could reduced significantly the nutritional quality of fresh-cut apples. Dihydrochalcone (phloridzin) and chlorogenic acid levels were 2 to 21-fold higher in apple core than skin and flesh. TAC levels and vitamin C contents could be increased up to 3-fold and 14 to 20-fold, respectively by the post-cut dipping treatment with an ascorbic acid-based antioxidant formula. The phenolic profiles of sliced apples were stable up to 21 days at 4°C.

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