• Journal of Microbiology and Biotechnology
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• v.32 no.7
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• pp.892-901
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• 2022

The rising demand for carotenoids can be met by microbial biosynthesis as a promising alternative to chemical synthesis and plant extraction. Several species of lactic acid bacteria (LAB) specifically produce C₃₀ carotenoids and offer the added probiotic benefit of improved gut health and protection against chronic conditions. In this study, the recently characterized Lactiplantibacillus plantarum subsp. plantarum KCCP11226^T produced the rare C₃₀ carotenoid, 4,4'-diaponeurosporene, and its yield was optimized for industrial production. The one-factor-at-a-time (OFAT) method was used to screen carbon and nitrogen sources, while the abiotic stresses of temperature, pH, and salinity, were evaluated for their effects on 4,4'-diaponeurosporene production. Lactose and beef extract were ideal for optimal carotenoid production at 25℃ incubation in pH 7.0 medium with no salt. The main factors influencing 4,4'-diaponeurosporene yields, namely lactose level, beef extract concentration and initial pH, were enhanced using the Box-Behnken design under response surface methodology (RSM). Compared to commercial MRS medium, there was a 3.3-fold increase in carotenoid production in the optimized conditions of 15% lactose, 8.3% beef extract and initial pH of 6.9, producing a 4,4'-diaponeurosporene concentration of 0.033 A₄₇₀/ml. To substantiate upscaling for industrial application, the optimal aeration rate in a 5 L fermentor was 0.3 vvm. This resulted in a further 3.8-fold increase in 4,4'-diaponeurosporene production, with a concentration of 0.042 A₄₇₀/ml, compared to the flask-scale cultivation in commercial MRS medium. The present work confirms the optimization and scale-up feasibility of enhanced 4,4'-diaponeurosporene production by L. plantarum subsp. plantarum KCCP11226^T.

• The Korean Journal of Mycology
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• v.34 no.1
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• pp.39-53
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• 2006

This studies investigated the effect of concentrations of sodium chloride (NaCl) on occurrence and growth of fruitbody in oyster mushrooms, Pleurotus spp. Our experiments divided into two parts. When the water contents in substrate were added with sodium chloride solution in cotton waste box cultivation as a first experiment, the growth of mushroom was damaged as the concentration was increased, even though there was a little difference according to the strains. The yield in 1.0% NaCl solution was decreased to 72% compared to non-treated plot while that in 3.0% solution was only 2% of the non-treated plot. Morphological characteristics of mushrooms cultivated in substrate with the different concentration of the solution showed different results. For example, the size and thickness of pilei were not influenced by NaCl concentration, but the length of stipes and individual weight were much influenced. In plastic box cultivation filled with cotton waste, watering treatment with the different concentrations of sodium chloride solution, the second experiment, did not show any difference according to the concentration until 1.0% solution but there was a little difference according to the strains. The productivity of fruitbody started to decrease at 2.0% of the solution and the yield and quality of mushroom in 3.0% solution treatment were generally low. After the second flush, days for mushroom sprouting were generally prolonged in proportion to the solution concentration. Taken altogether, the second experiment did not show a clear effect as the case of the first experiment.

• Journal of Food Hygiene and Safety
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• v.26 no.3
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• pp.273-282
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• 2011

This study established hazards which may cause risk to human at farm during cultivation stage of paprika. Samples of plants (paprika, leaf, stem), cultivation environments (water, soil), personal hygiene (hand, glove, clothes), work utensils (carpet, basket, box) and airborne bacteria were collected from three paprika farms (A, B, C) located in Western Gyeongnam, Korea. The collected samples were assessed for biological (sanitary indications and major foodborne pathogens), chemical (heavy metals, pesticide residues) and physical hazards. In biological hazards, total bacteria and coliform were detected at the levels of 1.9~6.6 and 0.0~4.610g CFU/g, leaf, mL, hand or 100 $cm^2$, while Escherichia coli was not detected in all samples. In major pathogens, only Bacillus cereus were detected at levels of ${\leq}$ 1.5 log CFU/g, mL, hand or 100 $cm^2$, while Staphylococuus aureus, Listeria monocytogenes, E. coli O157 and Salmonella spp. were not detected in all samples. Heavy metal and pesticide residue as chemical hazards were detected at levels below the regulation limit, physical hazard factors, such as insects, pieces of metal and glasses, were also found in paprika farms. Proper management is needed to prevent biological hazards due to cross-contamination while physical and chemical hazards were appropriate GAP criteria.

• Korean journal of applied entomology
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• v.46 no.2
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• pp.325-330
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• 2007

Among various food base baiting materials, beer and macerated cucumber were the most effective to induce slug that is a troublesome pest on leafy vegetables, especially on lettuce. However, the baits attracted only but did not kill the pest. When the baits were combined with various insecticidal organic materials, a few combinations such as beer and cigarette mixture successfully induced and killed the slug in the field test. The most effective combination of beer 50ml and a cigarette contained in a small plastic box killed 25 slugs per night. While macerated cucumber 50ml and a cigarette mixture killed only 4.3 slugs. The bait of beer and cigarette mixture revealed 68.4% control value against slug damage when treated for 3 consecutive days in a lettuce cultivation greenhouse. The bait also effectively reduced the slug damage in a lettuce nursery showing 58.3% control value. The method seemed highly useful for the control of slug in the organic farming system in which application of pesticides are strictly prohibited.

• Proceedings of the Korean Society of Life Science Conference
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• 2001.06a
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• pp.67-86
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• 2001

A strain producing strongly fibrinolytic enzyme was isolated from soil and was identified to be Bacillus subtilis by biochemical and physiological characterization. The optimal culture conditions for the production of fibrinolytic enzyme was determined to be 1.0% tryptone, 1.5% soluble starch, 0.5% Peptone, 0.5% NaCl, $(NH_{4})_{3}PO_4.3H_{2}O, and MgSO_{4}.7H_{2}O.$ Initial pH and temperature were pH 8.0 and $30^{\circ}C$ , respectively, The highest enzyme production was observed at 30 hours of cultivation at $30^{\circ}C$ The fibrinolytic enzyme was purified to homogeneity by DEAE Sephadex A-50 ion exchange column chromatography, 70% ammonium sulfate precipitation, Sephadex G-200 and G-75 gel filtration column chromatography. The molecular weight of the purified enzyme was 28,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A gene encoding the fibrinolytic enzyme was cloned into a plasmid vector pBluescript, transforming E.coli XL-1 Blue. The clone was able to degrade fibrin, This indicated that the gene could encode a fibrinolytic enzyme. The nucleotide sequence of the 2.7 kb insert was determined in both direction. One open reading frame composed of 1023 nucleotides was found to be a potential protein coding region. There was the putative Shine-Dalgano sequence and TATA box upstream of the open reading frame. The homology search data in the genome database showed that both the 2.7 kb insert and 1 kb open reading frame carried no significance in the nucleotide sequence of known fibrinolytic enzyme from Bacillus serovars. The recombinant cell harboring the novel gene involved in fibrinolysis was subjected to protein purification. The molecular mass of the purified fibrinolytic enzyme was determined to be 31864 Dalton, which was highly in accordance with the molecular mass(33 kDa) of the fibrinolytic gene deduced from the insert. The fibrinolytic enzyme was Purified 50.5 folds to homogeneity in overall yield of 10.7% by DEAE Sephadex A-50 ion exchange, 85% ammonium sulfate precipitation, Sephadex G-50, Superdex 75 HR FPLC gel filtration. In conclusion, a novel fibrinolytic gene from Bacillus subtilis was identified and characterized by cloning a genomic library of Bacillus subtilis into pBleuscript. For the soybean fermented by this strain, it is found that there increased assistant protein about 20% compared to the soybean not fermented and increased about 30% according to amino acid analysis and, in particular, essential amino acid increased about 40%. When keeping this fermented soybean powder at room temperature for about 70days, it showed very high stability maintaining almost perfect activity and, therefore, it gave us great suggestion its possibility of development as a new functional food.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.230-236
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• 1992

To study the effects of different nursing methods and transplanting on the growth of the rice plant(Oriza sativa L.hn southern region of Korea, Kumo-byeo, Palgong-byeo and Dong-jinbyeo were transplanted from April 20 to July 20 with 15 days intervals as 8 days seedling (infant rice), 25 days box seedling for machine transplanting and 45 days conventional seedling, respectively. No. of leaves at transplanting were in order of 45 days seedling>25 days seedling>8 days seedling. In 25 days seedling, they were increased as transplanting dates were later from April 20 to June 5, and in 45 days seedling, it showed same tendency until June 5 with Dongjinbyeo, June 20 with Palgong-byeo and Kumo-byeo. Root activity according to the $\alpha$-naphthylamine oxidation activity and rooting activity were higher in order of 8 days seedling>25 days seedling>45days seedling. Panicle formation initiated after maximum tillering stage as transplanting at April 20 with 8 days seedling and 25 days seedling, but it intiated before maximum tillering stage as transplanting at July 20 in Kumo-byeo. and in Palgong-byeo intiations of panicle formation were shown after maximum tillering stage as transplanting until May 20, but June 5 in Dongjin-byeo. However, there was no significant tendency with 45 days seedling. Missing hill ratio were less than 5% as transplanting with 8 days seedling and 25 days seedlingregardless of transplanting periods or varieties.

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.36-43
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• 2008

This purpose of this study was to examine the effect of planting density, growing medium and strength of a nutrient solution (National Horticultural Research Institute's nutrient solution: HRI's) on the growth and development of Oriental hybrid lily 'Le Reve' in a box cultivation. The planting density with 14, 18 and 22 bulbs had sprouting one day earlier than other treatments. Planting density of 22 bulbs flowered first, while six bulbs flowered the last, indicating that higher planting densities led earlier flowering. The increasing planting density increased stem length of cut flowers. On the other hand, cut flower quality was improved when the planting density was lower. The incidence of physiological disorders such as blasting was more frequent in planting density of 22, 18, and 14, indicating that higher planting densities caused higher incidences of physiological disorders. All planting densities except 22 bulbs displayed superior results in width, weight, number, and scale weight of the bulbs. Greater planting densities led to inferior bulb enlargement and an increased decomposition rate. pH decreased in all treatments after the bulb enlargement and decreased more as the planting density increased. Contents of P, K, Ca, and Mg increased, while contents of K and Ca decreased, as the planting density increased. The rice hull+coir (1:1, v/v) treatment was better than others, but did not show that much of a difference. Moreover, in bulbs enlargement after cut flower harvest, lily medium and perlite+peat moss treatments showed superior results, and decomposition rate was the greatest in the rice hull+coir (1:1, v/v) treatment. In the HRI's solution strength treatment from the period of flower bud emergence to flower harvest, higher solution strengths gave better cut flower quality in terns of length, weight, and number of flowers. The non-treated control and one third strength of a HRI's solution hastened flowering, indicating that lower strengths led to earlier flowering. According to the results of leaf analysis as affected by solution strength during the flower harvest, absorption rates of N and K were greater when the strength was higher, and Ca and Mg showed the same tendency. On the other hand, the absorption rate of P was the lowest in all treatments.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.615-622
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• 2013

The purpose of this study was to evaluate microbial contamination of melons in Korea. A total of 123 samples including melon fruits, leaves, seeds, soils, and irrigation water were collected from farms and markets to detect total aerobic bacteria, coliform, Escherichia coli, and pathogenic bacteria such as Bacillus cereus, Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus. Samples were collected from Iksan and Nonsan farms to monitor bacterial levels on pre-market melons. The total aerobic and coliform bacteria on melon cultivation were between 0.43 and 6.65 log CFU $g^{-1}$, and 0.67 and 2.91 log CFU $g^{-1}$, respectively. Bacillus cereus, a fecal coliform, was detected in soils and melon leaves from Iksan farm at 2.95, 0.73 log CFU $g^{-1}$, respectively, and in soils from Nonsan farm at 3.16 log CFU $g^{-1}$. Market melon samples were collected to assay bacterial load on melon being sold to consumers. The contamination levels of total aerobic bacteria in agricultural markets, big-box retailers, and traditional markets were 4.82, 3.94, 3.99 log CFU $g^{-1}$, respectively. The numbers of coliform in melon on the markets ranged from 0.09 to 0.49 log CFU $g^{-1}$. Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus were not detected in any samples. The count of total aerobic bacteria on melon seeds ranged from 0.33 to 3.34 log CFU $g^{-1}$. This study found that irrigation water, soil, manure and various farm work activities including post-harvest processes were latent sources of microbial contamination. These results suggest that hygienic management and monitoring of soil, water, and agricultural material should be performed to reduce microbial contamination in melon production.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.554-564
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• 2017

The purpose of this study is to assist farmers in determining the optimal time for the shipment of stored apples by investigating the market trends, storage status and release dates of low-temperature stored apples. We surveyed 300 apple cultivation farms in Daegu, Gyeongbuk Province, which is the main producer of apples, and examined the cultivars, cultivation areas, storage conditions, and shipment status of apples. The main results are as follows: the proportion of apples cultivatedat different ripening times was surveyed. According to the results, the proportions of early, middle and late varieties were 78.3%, 63.7% and 96.0%, respectively. Also, 48.7% of the farm households surveyed had cold storage facilities. The average storage cost per apple box(15kg) was 978.3 won for self-storage and 1,771.8 won for consignment storage. For the six(6) months between November and April, the proportion of shipped apples was 91.6% of the total stored apples. The (average total?)annual apple shipment, including apples stored in general storage warehouses, was 744.4 boxes. The (average total?) annual shipment of cold storage apples was 616 boxes. The stored apples were mainly shipped to 'wholesale markets', which have the highest sales share, followed by 'production site collectors' and then 'supermarkets'. The most common shipping method of the apples was by general trucks, followed by low-temperature trucks, and finally by delivery services. The analysis of the factors influencing the decision to release apples by period showed that it was affected by the storage cost, loss rate, and customary shipping in the off-season(from May to August). On the other hand, in the general release season(from November to April), the statistically significant decision factors for the release of apples were the future expected price, storage cost and decision of the leading farmer groups. For farmers with a high share of general shipment, the deciding factors for the release of apples were the future expected price, storage cost, high income expectation, and decision by leading farmers.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.153-158
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• 2013

This research was carried out to investigate silicon (Si) uptake levels by six potted plant species from a nutrient solution supplemented with $K_2SiO_3$. Uniform rooted plants of Dendranthema grandiflorum Ramat., Spathiphyllum patinii N.E. BR., Kalanchoe blossfeldiana, Hedera helix L., Dianthus caryophyllus L., and Euphorbia pulcherrima Willd. were grown in 350 mL boxes, one plant per box, containing a nutrient solution supplemented with either 0, 2.7, or 5.4 mM Si as $K_2SiO_3$. The nutrient solution in each container was adjusted to EC $1.5mS{\cdot}cm^{-1}$ and pH 5.6. The solution in each container was aerated by an 1 m-long polyethylene tube, all connected to a vacuum pump. After 15 days of cultivation in a glasshouse Si contents in the roots and shoots were measured using the colorimetric molybdate method and amount of remaining Si in the nutrient solution was measured using the ICP-AES to calculate the amount of absorption. A simple regression analysis was performed to observe the changes in Si contents in the roots and shoots as affected by concentration of Si supplied to the solution. Among the six species tested, carnation had the greatest and poinsettia the lowest tissue levels of Si concentration in the root, whereas carnation had the greatest and kalanchoe the lowest tissue levels of Si concentration in the shoot. Based on the Si content in the whole plant, Si uptake levels by poinsettia, kalanchoe, and chrysanthemum were low, whereas those by spathiphyllum were intermediate, and those of English ivy and carnation were high. These results indicated that the uptake level of Si by the plant vary depending on plant species.