• Korean journal of applied entomology
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• v.38 no.2
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• pp.101-107
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• 1999

Queens of Korean native bumblebee species, Bombus ignitus were collected from the field in the spring of 1998 to investigate their ecological characteristics and reared under the laboratory conditions; 3 0 f 1$^{\circ}$C, 55 25% of relative humidity and darkness. As a result, 94.4% of the queens laid eggs in 6.00f 2.41 days after the field collection. The first worker and the first drone from the egg cell of the collected queens appeared in 18.90 f 1.16 and 68.96 f 3.94 days, respectively. In the colony foundation, 86.1% of the collected queens founded their colony, and 96.8% of them produced new queens in 71.14f 6.88 days. The life span of the colony-founded queen covered for 86.90f24.35 days, whereas that of non-colonized queen for 15.67 f 7.37 days. One colony sized as big as 987.82f 145.84 in number, composing of workers (188.79f 18.23), drones (691.10f 159.24) and queens (107.93 f47.48). Copulation lasting time of queen and drone took 23.00f 7.33 minutes in average. In a new queen emergence, there were two patterns; single peak type of new queen emergence in 12.31 k6.95 days and two peaks type of it in 74.00f 17.61 days. The number of eggs per egg cell of new queen averaged as 8.86f 4.00 grains and an egg period covered 3 days after oviposition. An egg cell sized as 7.15 f0.88 mm in a width, 7.79 f 1 .l 1 mm in a length and 3.33 f 0.23 mm in a height. An egg shaped as banana and sized as 1.22 f 0.09 mm in a width and as 3.5 1 f 0.21 mm in a length, weighing as 2.70 + 0.30 mg.

• The Korean Journal of Food And Nutrition
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• v.7 no.2
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• pp.95-99
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• 1994

In order to investigate the fatty acid composition of Korean pumpkins, this study was designed. Three samples of Korean pumpkins, A(yellowish ripe), B(unripe, 30 days old) and C(unripe, 20 days old) were used for fatty acid analysis by gas chromatography. The results were as follows : Pumkin C, B and A showed 10, 12 and 15 kinds of fatty acids, respectively. In case of palmitic acid(C16:0), pumpkin C, B and A showed 22.5%, 22.9% and 26.6%, respectively. In case of u linolenic acid(C18:3), pumpkin C, B and A showed 22.6%, 23.6% and 44.8%, respectively. In case of palmitoleic acid(Cl6:1), pumpkin C. B and A showed 12.4%, 10.1% and 0.5%, respectively. In case of oleic acid(C18:1), pumpkin C. B and A showed 9.2%, 7.7% and 2.8%, respectively, In case of stearic acid(C18:0), pumpkin C, B and A showed B.S%, 3.7% and 3.5%, respectively. The ratio of P/S was 1.4, 1.6 and 1.9 for sample C, B and A, respectively. The ratio of w-3/w-6 was 1.1, 0.9 and 2.6 for sample C, B and A, respectively. Through this study, the ripe pumpkin(sample A) was thought to be good enough in nutritional aspects of fatty acids, particularly a-linoleic acid, Cl8 : 3(u-3) series.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.3
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• pp.207-211
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• 1983

An attempt was made to find out the possibility of utilizing water-melon seed as resources of food fats and protein. The water-melon seed contained 40.40% of crude fat and 28.36% of crude protein. The lipid fraction obtained by silicic acid column chromatography was composed of about 97.35% neutral lipid, and the main components of neutral lipid by thin layer chromatography were triglyceride(50.40%), diglyceride(21.84%) and sterol(11.48%). The predominant fatty acids of total and major lipid classes were linoleic acid(55.30-67.85%), palmitic acid(12.07-28.12%) and oleic acid(9.06-16.40%), whereas stearic acid and linolenic acid were detected as small amounts. The salt soluble protein of watermelon seed was highly dispersible in 0.02M sodium phosphate buffer containing about 0.7M $MgSO_4$, and the extractability of seed protein was about 27%. Glutamic acid and arginine were major amino acids, and the essential amino acids such as lysine, threonine, valine, methionine, isoleucine, leucine and phenylalanine were also detected. The electrophoretic analysis showed 6 bands in water-melon seed protein, and the collection rate of the main protein fraction purified by sephadex G-100 and G-200 was 52.4%. The amino acids of the main fraction protein were also mainly composed of glutamic acid and arginine. The molecular weight for the main protein of the water-melon seed was estimated to be 120,000.

• Food Science and Preservation
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• v.24 no.1
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• pp.44-51
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• 2017

For the production of Yakhobak (Cucurbita maxima subsp. maxima) paste under various heating conditions, we steamed Yakhobak for roughly 20 min, followed by heating under high pressure treatment for 0 min (HHP0), 20 min (HHP20), 40 min (HHP40), and 60 min (HHP60). The physicochemical and sensory characteristics were subsequently investigated. Generally, no significant difference was observed in organic acid content and sensory characteristics score between Yakhobak paste treated with and without high-pressure heating. However, there was a significant difference in color value, soluble solids, and free sugar content. The L value for color of the group HHP0, untreated control Yakhobak paste (no high-pressure heating), decreased as time increased from 20 min to 60 min, with L values of 44.33, 44.25, and 42.86, respectively. The b value for the color of Yakhobak paste also decreased, showing a significant difference. Soluble solids and free sugar (fructose, glucose, sucrose) contents of the high-pressure heat-treated groups HHP20, HHP40, and HHP60 decreased compared with untreated group HHP0. Organic acid composition of Yakhobak paste included citric acid, malic acid, and fumaric acid, and the major organic acid was malic acid. Sensory score of HHP40 was the highest among all experimental groups in terms of overall preference, but there was no significant difference.

• Microbiology and Biotechnology Letters
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• v.38 no.2
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• pp.177-182
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• 2010

The goal of this study was to characterize the quality and physiological functionality of some traditional rice wines in Chungnam province, Korea. Non-sterilized and commercial sterilized traditional rice wines from five traditional rice wine factories of Chungnam province were collected and investigated for nutritional components, noxious compounds and physiological functionality. Ethanol content ranged from 16.1~18.3% and pH ranged from 3.27~4.76, and they also contained 0.15% to 0.55% of total acid. All traditional rice wines contained 10.15~139.9 mg% of amino nitrogen and 2.5~25.7% of total sugar. Among organic acids, lactic acid was contained 7.4~29.6 mg%, and succinic acid and propionic acid was also contained 0.2~2.7 mg% and 0.7~8.3 mg%, respectively. Antihypertensive angiotensin I-converting enzyme inhibitory activity were showed 37.0~86.0% in all rice wines, however, fibrinolytic activity, antioxidant activity, SOD-like activity and acetylcholinesterase inhibitory activity were low or not detected.

• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.65-69
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• 1998

To determine the amount of total bromide as 2-bromoethanol, the domestic agricultural products such as rice, barley, carrot, cucumber, apple, tomato, squash, green pepper, melon, strawberry, grape, peach, potato and celery were analyzed by GC/MSD as well as GC/ECD. The bromide was detected in most of the domestic samples and the highest bromide residue determined was 13.2 ppm in barley. The imported agricultural products including melon, kiwi, lemon, pineapple, banana, orange and grape were also analyzed for the bromide. The bromide was also detected in most of the imported ones and the highest bromide residue determined was 12.3 ppm in pineapple. In addition, the bromide residue in instant noodle spices was monitored for 4 years, recently. As results, in 1994, the bromide content was in the range of non-detection to 2.4 ppm (average 1.1 ppm) from 22 out of 24 samples; in 1995, the bromide content was 1.0 and 2.2 ppm from 2 out of 37 samples; in 1996, the bromide content was in the range of 0.7 to 37 ppm (average 12.4 ppm) from all 11 samples; and in 1997, the bromide content was in the range of 0.2 to 4.6 ppm (average 1.2 ppm) from all 59 samples. However, none of sample analyzed for the bromide was exceeded Maximum Residue Limit(s) of Korea and Codex in these survey.

• Journal of the Korean Applied Science and Technology
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• v.31 no.4
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• pp.642-652
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• 2014

The synthesis of octenyl succinyl ${\beta}$-gucan (OSA-${\beta}$-glucan) was carried out and its interfacial properties at the oil-water interface and in emulsion systems were investigated. An aqueous ethanol system as a reaction media was used to facilitate the synthesis process; 10% (w/w) ethanol found to be the best as it showed a maximum degree of substitution (DS: 0.0132). FT-IR showed a characteristic absorption spectrum at $1736cm^{-1}$, indicating the esterification of octenyl succinyl groups to ${\beta}$-glucan backbone. As for interfacial tension measurements, it was decreased with increasing concentration of OSA-${\beta}$-glucan in the aqueous phase and when NaCl was added to aqueous OSA-${\beta}$-glucan solution in the range of 0.01 M to 0.1 M and also when pH was raised (pH 3 ~ pH 9). In systems of emulsion stabilized with OSA-${\beta}$-glucan, fat globule size found to decrease with increasing concentration of OSA-${\beta}$-glucan, showing a critical value of about $0.32{\mu}m$ at 0.5 wt%. When the OSA-${\beta}$-glucan emulsions were stored, it was found that fat globule size was increased with storage time and particularly pronounced increase was observed in emulsion with 1% OSA-${\beta}$-glucan, possibly due to depletion flocculation. Results of creaming stability evaluated by light scattering technique showed that it was more stable in emulsions containing smaller fat globule size. Surface load of OSA-${\beta}$-glucan in emulsions increased with increasing concentration of OSA-${\beta}$-glucan, suggesting a multilayer adsorption.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.217-223
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• 2015

We investigated the emulsifying properties of barley octenyl succinic anhydride (OSA)-${\beta}$-glucan, such as changes in the fat globule size and zeta-potential as influenced by pH or the addition of NaCl. Additional experiments to fabricate a suitable co-surfactant system were also performed. We found that the fat globule size in OSA-${\beta}$-glucan emulsions increased upon lowering the pH (i.e., under acidic conditions) or increasing the NaCl concentration. These results were confirmed through microscopic observation. Co-surfactant hydrophilic Tween 20 was found to be suitable for the OSA-${\beta}$-glucan emulsion, which facilitated the formation of smaller fat globules and enhanced the creaming stability when it was added in >0.2 wt% concentration. From the results of the surface load of OSA-${\beta}$-glucan in emulsions, Tween 20 addition enhanced the stability probably by the co-adsorption of the two surfactants at the droplet surface.

• Journal of Sericultural and Entomological Science
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• v.50 no.2
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• pp.161-165
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• 2012

Antimicrobial peptides of insects are found and reported as immune defence system against infectious agents. The peptides are produced by fat body cells and thrombocytoids, a blood cell type. Defensin is 38-45 amino acids long and consists of an ${\alpha}$-helix linked by a loop to an antiparallel ${\beta}$-sheet. Defensin from a bumblebee, Bombus ignitus, is known to comprise 52 amino acid residues. This peptide consists of two ${\alpha}$-helixes; ACAANCLSM and KTNFKDLWDKRF and one ${\beta}$-sheet; GGRCENGVCLCR. We carried out antibacterial activity test by radial diffusion assay against Staphylococcus aureus (Gram positive), Escherichia coli (Gram negative), Pseudomonas syringae (Gram negative), Candida albicans (fungi), MDRPA, MRSA, and VRE (antimicrobial resistant microbes) with synthetic oligopeptides from Peptron (Daejeon, Korea). The predicted curtailment fragment (GGRCEVCLCR-$NH_2$) for ${\beta}$-sheet had strong antibacterial activity when internal amino acids were removed. But, curtailment fragments (ACAANCLSM-$NH_2$ and TNFKDLWDKR-$NH_2$) of ${\alpha}$-helix were not showed antibacterial activity. These synthetic oligopeptides were showed the great activity against Gram positive and negative bacteria.

• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.152-157
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• 2023

This study was aimed to investigate pesticides residue levels in nuts and seeds distributed in Gyeonggi-do. We investigated nuts and seeds in 131 products, which is pumpkin seeds (n=17), sunflower (n=12), sesame (n=23), perilla (n=11), peanut (n=18), almond (n=8), chestnut (n=6), walnut (n=14), pine nut (n=3), pecan (n=4), macadamia (n=3), brazil nut (n=5), cashew nut (n=4) and ginkgo nut (n=3). As a result of evaluating 339 pesticide residues, eight out of 131 samples were detected at the range of 0.01-0.07 mg/kg. Additionally, 7 out of 8 detected samples exceeded MRLs (Maximum Residue Limits) and 85% of them were imported. Pyraclostrobin applied on the positive list system (PLS) was detected in five Chinese pumpkin seeds samples, and the range was 0.02-0.04 mg/kg. In Indian and Korean sesame seeds, pendimethalin, boscalid, and bifenthrin were detected at 0.04, 0.05, and 0.06 mg/kg, respectively. The ratio of estimated daily intake (EDI) to acceptable daily intake (ADI) was 0.002-0.372%, indicating that the risk level was safe.