• Journal of Embryo Transfer
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• v.16 no.2
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• pp.79-89
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• 2001

Steroid hormones control the expression of many cellular regulators, and a role thor estrogen in mouse oocytes has been well documented. The preovulatory $E_2$increment is generally accepted as the endocrine process regulating induction of in vivo oocyte maturation To address whether the activity of the T-type $Ca^{2+}$ channel is altered by 17 beta-estradiol ( $E_2$), we examined the actions of $E_2$on the calcium channel of mouse oocytes and early embryos. Oocrtes were collected from the oviduct of mice treated with pregnant mare's serum gonadotropin (PMSG) and human choronic gonadotropin (hCG). Whole cell voltage clamp technique and confocal microscopy were used to examine that $E_2$increase intracellular $Ca^{2+}$ concentration ([C $a^{2+}$]$_{i}$ ) via voltage dependent $Ca^{2+}$ channel (VDC) and estrogen receptor (FSR), and $E_2$concentration by the use of radioimmunoassay (RIA) were examined in mouse. The results obtained were as follows: The peak of $Ca^{2+}$ current induced by $E_2$increased 122% to 1.50$\pm$0.03 nA from 1.23$\pm$0.21 nA (n=15) in the presence of 5 mM extracellular $Ca^{2+}$ concentration ([C $a^{2+}$]$_{o}$ ). The increased $Ca^{2+}$ current was temporally associated with $Ca^{2+}$ transients. The intracellular $Ca^{2+}$ level increased 207%~30 s following the addition of 1${\mu}{\textrm}{m}$ $E_2$(relative fluorescence intensity: 836.4$\pm$131.2 for control, n=10, 1736.4$\pm$192.0 in the presence of $E_2$, n=10). $E_2$increased amplitude of $Ca^{2+}$ current and [C $a^{2+}$]$_{i}$ . $E_2$-induced $Ca^{2+}$ current and $E_2$concentration in blood were showed difference on the stage of embryo. These results suggest that $E_2$modulate $Ca^{2+}$ channel to increase $Ca^{2+}$ influx.$Ca^{2+}$ influx.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.178-183
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• 2014

This study aimed to evaluate the fruit quality characteristics and incidence of flesh browning in response to air storage at $0{\pm}1^{\circ}C$ a fter controlled atmosphere s torage (CA condition: $O_2$ $2.5{\pm}0.5$%, $CO_2$ $1.5{\pm}0.5$%) at $0{\pm}1^{\circ}C$ in 'Fuji' apples (Malus domestica Borkh.). The storage system was performed as followed: air storage for one month, CA storage 4 months + air storage 3 months ( CA 4M + A ir 3M), CA storage 5 m onths + air storage 2 months ( CA 5M + Air 2M) a nd C A storage 6 m onths + air storage 1months (CA 6M + Air 1M), while the control fruits were stored at CA storage for 8 months right after harvest. The incidence of flesh browning ranged from 17.1% to 30.2% during CA storage but not detected under the treatments of CA 4M + Air 3M and CA 5M + Air 2M. The respiration rate was not affected by storage treatments for 6M while the respiration rate was lower in the treatments of CA 4M + Air 3M and CA 5M + Air 2M than the other storage treatments after 7 months. Ethylene production and internal ethylene concentration were lowest in rapid CA storage and increased with a decreasing CA storage duration. Therefore, the results indicate that CA 5M + Air 2M storage treatment should be recommended to maintain the fruit quality and reduce the risk development of flesh browning rather than typical CA storage in 'Fuji' apples.

• Korean Journal of Organic Agriculture
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• v.19 no.1
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• pp.83-92
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• 2011

This study was established to investigate the effects of Ca application on fruit mineral nutrients, quality, and browning of 'Fuyu' sweet persimmon (Diospyros kaki). Ca foliar application at 40ml/20L/tree had a greater fruit Ca concentration than did control, Ca fertigation (40ml/20L/tree), and Ca foliar application (40ml/20L/tree) coupled with IBA fertigation (40ml/20L/tree). Fruit mineral nutrient concentrations for Mg, B, and Mn were similar or lower in the foliar treatment compared to other treatments. Fruit color was not affected. Ca treatment, whether foliar applied or fertigated, was effective in maintaining fruit firmness and in decreasing the browning symptom in fruit after MA storage at $0^{\circ}C$ for 60 and 100 days. Although Ca foliar application + IBA fertigation treatment improved fruit firmness, the positive effect on the browning and decay occurrences in fruit was not shown.

• Horticultural Science & Technology
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• v.29 no.3
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• pp.224-231
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• 2011

Effects of 1-methylcyclopropene (1-MCP) treatment and controlled atmosphere (CA) storage was analyzed for the export quality of 'Fuji' apples after 8-month storage. Apples were harvested from two orchards located in different regions at relatively late stage of maturity for long-term storage. Fruit were treated with 1 ${\mu}L{\cdot}L^{-1}$ 1-MCP and then stored in $0^{\circ}C$ air or CA with 1.5 kPa $O_2$ and < 1.0 kPa $CO_2$ for 8 months. To simulate poststorage export process such as 2-week refrigerated container shipment plus 7-day local distribution, fruit were put in $0^{\circ}C$ air storage for additional two weeks and then on the shelf for 7 days at $20^{\circ}C$. Both the 1-MCP treatment and CA storage reduced respiration and ethylene evolution after storage and shipping simulation, and successfully maintained titratable acidity and flesh firmness even after the export process. In 'Fuji' apples harvested after adequate stage of maturity for long-term storage, however, 1-MCP treatment alone seemed not to be satisfactory for the maintenance of sensorial fruit texture for export market. CA storage or 1-MCP treatment/CA storage combination program should be applied for lately harvested 'Fuji' apples exported after eight months storage.

• Horticultural Science & Technology
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• v.19 no.1
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• pp.12-16
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• 2001

This study was conducted to evaluate the effect of calcium chloride treatment (0.1%, 0.3%, and 0.5%) in red sweet pepper 'Ace' on the improvement of shelf-life and the physiological characteristics. $C_2H_4$ production and respiration rates of fruits treated with $CaCl_2$ before harvest decreased during storage of red sweet pepper at $7^{\circ}C$. Ca contents in the leaves and in the fruits showed also a greater increase in treatment of $CaCl_2$ than that in control. No difference was found in total sugar, whereas sucrose content was rapidly reduced after 20 days at $7^{\circ}C$. Ascorbic acid contents were increased by the $CaCl_2$ treatment. As Ca concentration is getting higher, the fruit decay rate was significantly reduced. From this result, we can positively conclude that foliar application with the concentration of 0.3% $CaCl_2$ and 0.5% $CaCl_2$ before harvest is effective in improving storage quality in red sweet pepper.

• Food Science and Preservation
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• v.30 no.5
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• pp.822-832
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• 2023

This study investigates the effectiveness of CA (controlled atmosphere) containers in maintaining the freshness of exported melons. The melons were harvested on June 5, 2023, in the Yeongam area of Jeollanam-do, Korea. The CA container was loaded with melon samples packed in an export box. The temperature inside the container was set at 4℃, while the gas composition was set at 5% oxygen, 12% carbon dioxide, and 83% nintrogen. Following two weeks of simulated transportation, quality analysis was conducted at 10℃. The melons were inoculated with spore suspensions, and the decay rate was determined to investigate the effect of the gas composition inside the CA container on suppressing the occurrence of Penicillium oxalicum in melons. The results were compared with a Reefer container set at the same temperature. The samples transported in the CA container exhibited lower weight loss. The melon pulp softening, respiration rate, and ethylene production were slower using the CA container. Moreover, the decay rate during the distribution period in the CA container was lower than in the Reefer container. In contrast, the firmness of melons transported in the Reefer container decreased significantly (from 9.03N to 5.18N) immediately after transportation. The soluble solid content (SSC) of melons transported in the Reefer container also decreased rapidly. The results suggested that the CA container is the optimal export container for maintaining the freshness of melons.

• Korean Journal of Environmental Agriculture
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• v.15 no.4
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• pp.434-441
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• 1996

This study was conducted to clarify the degradation pattern, safety evaluation and penetration ratio of benomyl and bitertanol to apple used as postharvest fungicides during CA(controlled atmosphere) and cold storage. In CA storage, the degradation of benomyl and bitertanol in stored apple was slow at the early stage, while that in cold storage was, on the contrary, faster at the early stage. The initial concentrations of benomyl and bitertanol in apples applied at the standard application concentrations were 2.24 and 1.54mg/kg, respectively, and their residual amounts were below the maximum residue limits, 1mg/kg at 135 and 96 days in CA storage, 115 and 70 days in cold storage, respectively. The half-lives of benomyl and bitertanol in stored apples were 124 and 130 days in CA storage, 101 and 111 days in the cold storage, respectively, indicating that the degradation was faster in cold storage than in CA storage. The residual amount of benomyl and bitertanol in stored apples was retained more in peels than in pulps of apples.

• Horticultural Science & Technology
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• v.30 no.6
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• pp.725-733
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• 2012

Effects of postharvest 1-methylcyclopropene (1-MCP) treatment, controlled atmosphere (CA) storage, and shelf temperature on quality of 'Gamhong' apples were analyzed during export simulation. Fruits were harvested at the optimum maturity for long-term storage, treated with $1{\mu}L{\cdot}L^{-1}$ 1-MCP for 16 hours, and then stored for 6 months under air and CA conditions at $0^{\circ}C$. Poststorage export procedure was performed by applying additional 2-week refrigerated storage and 7-day shelf-life test at 7 and $20^{\circ}C$, which simulated container shipment and local distribution, respectively. After storage and during export simulation, rates of respiration and ethylene evolution were significantly lower in 1-MCP treated and CA-stored apples. For the reduction of respiration, CA storage was more effective than 1-MCP treatment. Soluble solids content was maintained higher in 1-MCP treated apples, while titratable acidity was maintained better both in the 1-MCP treated and CA-stored apples. Effects of 1-MCP treatment and CA storage were highly significant in maintaining flesh firmness and sensory texture ratings. Additive effects from combined application of 1-MCP treatment and CA storage were occasionally observed. Shelf temperature during the local distribution simulation seemed not to significantly influence quality changes only showing limited effects on flesh firmness. Overall results suggest that storage potential of 'Gamhong' apples is shorter than 4 months in control fruit under refrigerated air conditions, whereas the potential can be extended to longer than 6 months by 1-MCP treatment and CA storage. Postharvest program should be provided considering the time of export, i.e. period of storage, and duration of local distribution.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.1
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• pp.35-41
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• 2013

This study investigated the effect of functional MA films (FMA) incorporated with zeolite powder treated with 1 N HCL solution and anti-fogging agent on the freshness extension of Satsuma mandarin. Preference, weight loss, total ascorbic acid, sugar content, titratable acidity and gas composition in package of Satsuma mandarin were evaluated during storage at $15^{\circ}C$. After 120 days of storage, the weight loss of mandarin packed with LLDPE film (control, L) was 1%, FMA film (CA) was 1.6%. Total ascorbic acid content of Satsuma manderin in control was 19.97 mg%, those of CA was 24.25 mg%. The titratable acidity of Satsuma manderin in CA was higher than that of control, while soluble solids content of CA was lower than that of control after 120 days. Ethylene gas content of control was 89.5 ppm and those of CA was 73.6 ppm after 120 days. Quality of Satsuma mandarin packed with CA was better than that of control. It was verified that shelf-life of Satsuma mandarin in control was 100 days and those of CA film was 130 days. Quality of Satsuma mandarin was few different between treated with anti-fogging agent and non-treated, but commodity of film treated with anti-fogging agent was considered better than that of non-treated.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.796-802
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• 1995

Oyijangachi, a traditional Korean brinded cucumber, was prepared by brinning the cucumbers in five different solutions for 48 hrs and then, was dipped into dipping sources(Kochujang, Doenjang and Ganjang) for 30 days of aging. Firmness, calcium content and enzyme activities(pectinesterase and polygalacturonase) changes were measured among the cucumbers which were treated by five different solutions during aging. The firmness of Kochujang Oyijangachi were the lowest after 10 days of aging for all from the five brining solutions because of "hollow phenomena" of cucumbers. Calcium contents of cucumbers after dipping into the five solutiosn increased as calcium content of the solutions increased and also increased when the cucumbers dipped into the dipping bases(Kochujang, Doenjang and Ganjang) because of calcium migration from the dipping sources into the cucumbers during aging. The calcium contents of the three dipping bases were ranged from 70mg% to 120mg% of Ca. The activity of polygalacturonase in the Oyijangachi decreased generally during aging and decreased rapidly during initial 5 days of aging. The activity of pectinesterase of cucumbers treated with 12% salts solutions(treatment 3, 4 and 5) were higher than those of cucumbers treated with 6% salts solutions(treatment 1 and 2).