• Horticultural Science & Technology
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• v.34 no.5
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• pp.665-676
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• 2016

As high temperature during citrus growing season has caused a serious problems including inferior coloration in production of mandarins in Korea, we were to investigate the expression pattern of several genes related with coloration during the ripening in high temperature condition of citrus fruits. The expression of genes related with sugar metabolism, cell wall degradation, and flavonoid synthesis in high temperature conditions was investigated in fruits of 'Haryejosaeng' (Citrus unshiu) and 'Shiranuhi' mandarin (C. reticulata). While the expression of beta-amylase (BMY), phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), and flavanone 3-hydroxylase (F3H) was differently induced, expression of polygalacturonase (PG) decreased dependently on temperature conditions. In 'Haryejosaeng' mandarin, while the expression of genes related to the skin coloration, such as CHS and F3H genes increased at $25^{\circ}C$, the expression of PAL and stilbene synthase (STS) genes were induced at $30-35^{\circ}C$ in all ripening stages. In 'Shiranuhi' mandarin, the expression of the BMY gene decreased at early time point in all temperature condition and then increased at $30-35^{\circ}C$ than at $25^{\circ}C$ in the ripening stage 2 to 3 of fruits. F3H and STS genes also showed the tendency to decrease at $30-35^{\circ}C$. Although the expression levels of genes in ripening stage 1 and stage 2 of fruits showed similar patterns in both 'Haryejosaeng' and 'Shiranuhi', the expression levels of genes were down-regulated in late ripening stage of 'Shiranuhi' fruits compared to 'Haryejosaeng'. In general, the mRNA levels of seven tested genes were higher in 'Haryejosaeng' than in 'Shiranuhi' mandarin, and expression of genes by high temperature was regulated sensitively in 'Haryejosaeng' compared to 'Shiranuhi' mandarin. Further investigations of expression of various genes based on transcriptome analysis in early ripening stage can provide valuable information about the responses to climatic changes in ripening citrus fruits.

• Korean Journal of Food Science and Technology
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• v.18 no.5
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• pp.335-338
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• 1986

A simple spectrophotometric technique using sequential extraction of pigments was attempted to perform color evaluation of raw 'Taimuri' tomato (Lycopersicon esculentum Mill.) fruits. The difference between summed absorbance of 80% acetone and chloroform extract at 480 nm and 660 nm reflected the maturity of rawtomato fruits. The measurement system presented was regarded as a simple and reliable method for objective color evaluation of tomato fruits. It seems possible to predict the degree of puffiness by weight per volume w/v ratio of tomato fruits during various stages of maturity.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.1
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• pp.80-87
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• 2016

This study was conducted to investigate the physicochemical properties and antioxidant activities of strawberries from different cultivars and ripening stages grown in Korea. Fragaria ananassa 'Seolhyang' and 'Janghee' in unripe and ripe stages were used in this study. Overall, firmness of unripe fruits was harder than that of ripe fruits, whereas firmness of 'Seolhyang' was harder than that of 'Janghee'. There was no significant difference in soluble solid content (SSC) between the two cultivars, whereas SSC increased when fruits matured. Total phenolic and flavonoid concentrations of 'Seolhyang' were greater than those of 'Janghee' cultivar. However, there was no ripening effect on total phenolic concentration in both cultivars. Total anthocyanin concentrations of the two cultivars were higher in ripe stage while that of 'Janghee' was greater than that of 'Seolhyang' statistically. Total antioxidant activities of 'Seolhyang' were greater than those of 'Janghee'. Total phenolic and flavonoid concentrations were highly correlated with antioxidant activities but there was no correlation between total anthocyanins and total antioxidant activities.

• Journal of Plant Biotechnology
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• v.46 no.3
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• pp.236-245
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• 2019

Fruit ripening is a genetically programmed process involving a number of biochemical and physiological processes assisted by variations in gene expression and enzyme activities. This process generally affects the phytochemical profile and the bioactive principles in fruits and vegetables. To appraise the variation in bioactive principles of fruits from Rosa rugosa during its ripening process, we analyzed the changes in antioxidant and anti-elastase activities and polyphenolic compounds during the four ripening stages of fruits. Overall, an extract of unripe fruits contained the highest levels of total phenolic and flavonoid contents, radical scavenging activity, reducing power, oxygen radical antioxidant capacity, and elastase inhibitory activity, compared with the extracts of fruits at other stages of ripening. Additionally, we found that the reduction of flavonoid content occurs because of decreased transcriptional levels of genes involved in flavonoid biosynthesis pathway during the ripening process. Based on HPLC analysis, we found that the extract of unripe fruits contained the highest amount of myricetin, caffeic acid, chlorogenic acid, syringic acid, and p-coumaric acid and suggested that the antioxidant and anti-elastase activities of the extract obtained from stage 1, should be mediated by the presence of these compounds. Additionally, we analyzed the interaction sites and patterns between these compounds and elastase using the structure-based molecular docking approach, and suggested that chlorogenic acid strongly interacted with elastase. Together, these findings suggest that the maturity of fruits has profound effects on the pharmaceutical value of R. rugosa.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.343-348
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• 2007

Starch contents play important roles in determining the fruit quality. Stawberry accumulates starch in the early stages and then mobilized into soluble sugars during fruit ripening. To date the molecular studies on the ADP-glucose pyrophosphorylase (AGPase), a key enzyme of starch biosynthesis, were not reported. cDNAs encoding small (FagpS) and large (FagpL1 and FaspL2) AGPase subunits were isolated from strawberry (Fragaria ${\times}$ ananassa Duch. cv. Niyobou). Both FagpS and FagpL1 cDNAs have open reading frames deriving 55-58 kDa polypeptides, where FagpL2 contains a partial fragment. Sequence analyses showed that FagpS has a glutamate-threonine-cysteine-leucine (ETCL) instead of a glutamine-threonine-cysteine-leucine (QTCL) motif found in all the dicot plants except for Citrus. In fruits, FagpS and FagpL1 were expressed in all stages with a little change in the amounts of transcripts. In the case of FagpL2, we were not able to detect any signal from all stages of fruit development and all tissues except for very a weak signal from the leaf. The results indicate that FagpL1 and FagpL2 show ubiquitous and leaf-specific expression patterns, respectively. The studies suggest that the starch contents in strawberry might be controlled by the expression of AGPase gene at both the transcriptional and post-transcriptional levels during fruit development.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.251-256
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• 2008

Changes in antioxidant activity of Rubus coreanus fruit of 3 clones (S13, S114, and S16), which were selected from different sites, were studied at different ripening stages. Antioxidant activities (tree radical scavenging activity and reducing power) were determined and their relationships to total phenolic contents and ascorbic acid were analyzed. The highest tree radical scavenging activities of 3 clones (S13, S14, and S16) were 79.39, 75.80, and 81.16% at $125\;{\mu}g/mL$, respectively. In general, the antioxidant activity and the related parameters, including total phenolic content and vitamin C content decreased during fruit ripening. Total phenolic contents of the R. coreanus fruits (S13, S14, and S16) were correlated with tree radical scavenging activity ($R^2=0.8114$, 0.9186, and 0.9714). These results improve knowledge of the effect of ripening on the antioxidant activity and related compounds contents that could help to establish the optimum R. coreanus fruit harvest data for various usages.

• Korean journal of applied entomology
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• v.28 no.2
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• pp.88-92
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• 1989

The Oriental tobacco budworm, Heliothis assulta (Guenee), larvae usually feed on the hot-pepper fruits and young tobacco leaves or buds in Korea. This experiment was conducted t(} compare their attraction to their host plants including fruits of the sweet-pepper and solanum uk kwang, besides the other two mentioned above. First instar larvae were most attracted to the hot-pepper fruits. Flowers or leaves of the hot pepper plants were not attractive either. When the hot-pepper fruits were compared for attractancy, based on developmental stages, relatively mature fruits, just before ripening, were the most attractive. Their extract with or without 10% ethanol also gave similar result to 1st instar larvae or 2~4 instar larvae, suggesting a possibility that there is an attractant(s) in the hot-pepper fruits.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.341-347
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• 2011

To develop a healthy functional food containing Rubus coreanus fruit (RCF) powder with different degrees of ripening, the composition, physicochemical properties, and antioxidant activity of native RCF during ripening were investigated and compared with Rubus occidentalis fruit (ROF). Ripened RCF was bright red in color, whereas ripened ROF was dull and dark red in color. The seeds of RCF were softer and smaller than those of ROF. Crude protein, crude lipid, and total sugar content of RCF powder increased with increased ripening time, whereas ash and total dietary fiber contents decreased with increased ripening time. Color differences increased with Increased ripening. Eighteen types of amino acids were analyzed from RCF, and glutamic acid had the highest content. RCF powder had the highest level of potassium and calcium and did not contain any hazardous metals. Mineral and organic acid contents decreased according to ripening.

• BMB Reports
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• v.41 no.7
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• pp.529-536
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• 2008

Cinnamate-4-hydroxylase (C4H) is a key enzyme in the phenylpropanoid pathway, which is responsible for synthesizing a variety of secondary metabolites that participate in development and adaptation. In this study, we isolated a full-length cDNA of the C4H gene from the Korean black raspberry (Rubus sp.) and found that this gene existed as a single gene. By comparing the deduced amino acid sequence of Rubus sp. C4H with other sequences reported previously we determined that this sequence was highly conserved among widely divergent plant species. In addition, quantitative real time PCR studies indicated that the C4H gene had a differential expression pattern during fruit development, where gene expression was first detected in green fruit and was then remarkably reduced in yellow fruit, followed by an increase in red and black fruit. To investigate the two peaks in expression observed during fruit development and ripening, we measured the flavonoid content. The content of the major flavanol of Korean black raspberry fruits was determined to be highest at the beginning of fruit development, followed by a gradually decrease according to the developmental stages. In contrast, the content of anthocyanins during the progress of ripening was dramatically increased. Our results suggest that the C4H gene in Korean black raspberry plays a role during color development at the late stages of fruit ripening, whereas the expression of C4H gene during the early stages may be related to the accumulation of flavanols.

• Food Science and Preservation
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• v.14 no.5
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• pp.511-515
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• 2007

'Ooishiwase' plum (Prunus salicina L.) fruits were harvested at three pre-climacteric stages of ripeness (stages 1, 2, and 3) and treated with 1-methylcyclopropene (1-MCP, $1\;{\mu}L/L$) for 24 hours at $10^{\circ}C$ before storage to evaluate the effectiveness of 1-MCP in extending shelf-life at $10^{\circ}C$. Ethylene production and respiration rates were significantly lower after 1-MCP treatment compared to those of control fruit, throughout the entire storage period. Also 1-MCP delayed plum softening and color changes. However the chemical 1-MCP had no effect on fruit soluble solid content changes, the preservative 1-MCP is an effective tool for quality improvement in plums, and extension of shelf life of the fruit and plums can safely be harvested at stage 3 of ripening, at which time the most desirable organoleptic attributes have been developed.