• Korean Journal of Plant Resources
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• v.19 no.3
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• pp.405-410
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• 2006

A series of aqueous or methanol extracts from four different Korean salad plants were assayed to determine their allelopathy and antioxidant activity. The extracts applied on filter paper in a Petri-dish bioassay significantly inhibited root growth of against alfalfa (Medicago sativa) seedlings. Leaf extracts from 40 g dry tissue $L^{-1}$ of Aster yomena was most phytotoxic to alfalfa root growth, and followed by that of Cirsium japonicum, Taraxacum officinale, and Ixeris dentate. Methanol extracts of plants dose-dependently increased DPPH free radical scavenging activity in vitro. Antioxidant activity of methanol extracts from the same plant species was investigated, and the result showed high DPPH free radical scavenging activity in Cirsium japonicum, Aster yomena, and Ixeris dentate, however, in Taraxacum officinale was least activity. By means of HPLC analysis, chlorogenic acid, p-coumaric acid, and total phenolics with 7.68, 17.47 and 18.64 mg, $100g^{-1}$, respectively, showed the highest amounts in methanol extracts from Cirsium japonicum leaves. These results suggest that Compositae salad plants contain water-soluble substances with allelopathic potential as well as antioxidant activity.

• Korean Journal of Plant Resources
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• v.20 no.6
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• pp.499-503
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• 2007

Antioxidant activity, total phenolics level and cytotoxicity of the methanol extracts from the young sprouts of 5 Korean woody salad plants were determined. Methanol extracts of Kalopanax pictus had the highest DPPH radical scavenging activity, with an $IC_{50}$ value of 23.5mg $100g^{-1}$, and followed by Valeriana fauriei(43.1mg $100g^{-1}$), and Morus alba(>100mg $100g^{-1}$). Total phenolic content showed the highest amount in methanol extracts from Kalopanax pictus(23.7mg $100g^{-1}$), and followed by Valeriana fauriei(22.7mg $100g^{-1}$), Aralia elata(16.8mg $100g^{-1}$) and Morus alba(14.2mg $100g^{-1}$). In a MTT assay, methanol extracts of Aralia elata with $IC_{50}$ values of 151.0 and $140.7{\mu}g\;mL^{-1}$ showed the most potent cytotoxicity on Calu-6 and MCF-7, respectively. On the other hand, methanol extracts of Kalopanax pictus($IC_{50}=96.5{\mu}g\;mL^{-1}$) showed the highest activity against HCT-116, and followed by those of Aralia elata($123.3{\mu}g\;mL^{-1}$), and Actinidia arguta($162.0{\mu}g\;mL^{-1}$). Total phenolic content of the tested plant extracts was correlated with the DPPH radical scavenging activity, suggesting the phenolic compounds may contribute to the antioxidant properties of Korean salad plants.

• Research in Plant Disease
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• v.23 no.4
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• pp.314-321
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• 2017

Acidovorax valerianellae had been reported a causal agent of bacterial black spot disease on corn salad in France, 2003 and on watermelon in Korea 2011. In this study, difference in host specificity between 2 groups, corn salad strains and watermelon strains, of Acidovorax valerianellae was recognized and compared. In the pathogenicity test, all 5 watermelon strains showed pathogenicity on the 6 Cucurbitaceae plants but not on corn salad, whereas 4 corn salad strains showed pathogenicity only on the corn salad. Utilization of Biolog substrates was different between watermelon strains and corn salad strains on 4 substrates, Malonic Acid, ${\alpha}-Hydroxybutyric$ Acid, ${\alpha}-Keto$ Butyric Acid, and Glycyl-L Glutamic Acid. The phylogenetic tree built with the 16S rDNA sequences showed that all of A. valerianellae stains was grouped into 1 clade separating from the other species of Acidovorax genus. Within A. valerianellae clade, watermelon strains and corn salad strains were separated into 2 sub-groups. REP-PCR analysis also separated the two groups. Host specificity, substrate utilization, and some genetic characteristics suggested that there are two pathogenic groups, watermelon group and corn salad group in A. valerianellae.

• Horticultural Science & Technology
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• v.35 no.2
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• pp.178-187
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• 2017

The aim of this study was to investigate the effect of different light sources on the levels of glucosinolates (GSLs) in rocket salad (Eruca sativa L.). The light sources used in the study were: natural light (Control-1 or 2), red light-emitting diodes(LEDs), blue LEDs, mixed red and blue LEDs (R+B LEDs), white LEDs, fluorescent lamps (FL), and fluorescent lamps plus UV-C (FL+UV-C). Two separate experiments were conducted [Experiment I: Control-1, Red LED, Blue LED, Mix (R+B) LED and Experiment II: Control-2, White LED, FL, FL+UV-C] because of the limited number of growth chambers in our laboratory. The rate of increase in the length of rocket salad leaves was the highest under red LEDs and, FL confirming that red LED and, FL affect the growth of rocket salad. We separated and identified seven types of GSLs from the rocket salad:glucoraphanin, diglucothiobeinin, glucoerucin, glucobrassicin, dimeric 4-mercaptobutyl GSL, 4-methoxyglucobrassicin, and gluconasturtiin. The highest total GSL contents in Eexperiment I was found in plants grown under in red LEDs ($4.30{\mu}mol{\cdot}g^{-1}\;dry$ weight, DW), and the lowest under blue LEDs ($0.17{\mu}mol{\cdot}g^{-1}\;DW$). The highest total GSL contents in Experiment II was found in plants grown under FL ($13.45{\mu}mol{\cdot}g^{-1}\;DW$), and the lowest in FL+UV-C ($0.39{\mu}mol{\cdot}g^{-1}\;DW$). Especially in Experiment II, the content of dimeric 4-mercaptobutyl, which has a strong aroma and spicy flavor in rocket salad, was higher under FL and white LEDs than in Control-2, increasing by approximately 14.9 and 3.2-fold respectively. Therefore, light sources such as red LEDs, white LEDs and FL affected the accumulation of GSLs in rocket salad.

• Journal of People, Plants, and Environment
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• v.22 no.2
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• pp.145-157
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• 2019

This study was conducted to examine the effects of horticultural therapy on depression and emotional balance of women with hearing impairment. Ten women with hearing impairment registered in the Mokpo branch of the Korean Association of the Hearing Impaired were selected, and participated in the horticultural therapy program composed of 14 sessions from May 15 to July 31. The horticultural therapy program consisted of 'planting tropical orchids,' 'making a dish garden,' 'making plum pickles,' 'decorating a table with flowers,' 'making a hanging pot with succulent plants,' 'making pressed flowers with hydrangea,' 'making a fan with pressed flowers,' 'making a terrarium,' 'making a flower basket,' 'making a mosquito repellent spray,' 'decorating a heart-shaped cup with flowers,' 'making a natural herbal soap,' 'making a hydrangea bouquet' and 'making watermelon salad.' The depression and emotional balance scales were used to examine the effects of the program and the pre- and post-program scores were compared. The mean value of depression statistically significantly decreased from 49.0 points before the program to 43.9 points after the program. In addition, the mean value of emotional balance statistically significantly increased from 0.3 points before the program to 2.3 points after the program. The activity of drawing a picture after each session was effective in reducing depression and improving positive emotional balance by expressing emotions through pictures. The programs preferred by women with hearing impairment included 'making plum pickles,' 'making pressed flowers with hydrangea,' 'planting tropical orchids,' 'making a mosquito repellent spray,' 'making a natural herbal soap,' and 'making watermelon salad.' In conclusion, horticultural therapy programs were effective in reducing depression and improving emotional balance of women with hearing impairment.

• Korean Journal of Plant Resources
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• v.21 no.6
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• pp.413-419
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• 2008

Phenolics level, total flavonoid content, and antioxidant were determined from the methanol extracts of the eight medicinal plants using roots. Total phenolics were found as the highest levels in the methanol extracts of Arctium lappa, and followed by Youngia sonchifolia and Cirsium japonicum. Total amount of the each phenol compounds were detected in C. japonicum extracts ($319.2\;mg\;kg^{-1}$) as the greatest component, and followed by A. lappa ($96.3\;mg\;kg^{-1}$) and Y. sonchifolia ($22.9\;mg\;kg^{-1}$). Total flavonoid content showed the highest amount in methanol extracts from A. lappa (68.1 mg $100\;g^{-1}$) and followed by Y. sonchifolia (11.2 mg $100\;g^{-1}$) Lycoris radiate extracts (87.2%) had the highest nitrite scavenging activity and followed by A. lappa (81.5%) and Y. sonchifolia (77.5%). Methanol extracts of A. lappa at 25 mg $100\;g^{-1}$ exhibited the highest DPPH radical scavenging activity by 90.8%, even though less activity than synthetic antioxidants Vitamin C or butylated hydroxytoluene (BHT). Level of polyphenols was highly correlated with anti oxidative activity ($r^2$ = 0.85). The results suggest that several medicinal plants selected had the potent biological activities, and that their activities were differential depending on plant species.

• Food Science and Preservation
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• v.16 no.5
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• pp.699-704
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• 2009

Commercially produced 'baby leaves' of Brassica campestris var. narinosa (Chinese cabbage) were used in the present study. Baby leaf vegetables were sown on 128 cell plug trays and harvested 30 days after sowing. For mechanical stress experiments, seedlings were thinned to three per cell, selected for uniformity, and watered at the base. Trays were treated with mechanical stress by stroking back and forth 50 times, using a sheet of A4 paper folded to double thickness. Plants were treated between 12:00 and 14:00 daily for 15-20 days. Harvested baby leaf vegetables were packed in MAP salad bags made of P-plus film, $50{\mu}m$ polypropylene (PP) film, and polyethylene terephthalate (PET) boxes. Fresh weight was well-maintained under P-plus and PP film on storage at $8^{\circ}C$. However, loss of fresh weight occurred quickly in PET boxes, and vegetable quality deteriorated rapidly. Stressed leaves were smaller but thicker, with an increased dry weight ratio. We thus suggest that P-plus or PP film is most appropriate packing for marketing of baby leaf vegetables, which should be stored at $8^{\circ}C$. Our data on baby leaf vegetables also make a significant new contribution in that we demonstrate a positive effect of stress touching on baby leaf processability.

• Korean Journal of Environmental Biology
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• v.41 no.3
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• pp.273-282
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• 2023

Hypochaeris radicata, native to Europe and Eurasia, is a perennial plant of the Asteraceae family. In Korea, H. radicata was reported in 1992, mainly in Jeju Island, and gradually spreading to the inland. It overwinters in the form of a rosette and blooms yellow flowers from May to June. H. radicata propagates by seeds and rhizomes. The germination temperature of the seed is 15/20℃ (day/night), and the rhizome forms a new plant at a depth of 2-3cm in the soil. The roots of H. radicata secrete allelochemicals that inhibit the development of other plants. Some use it as a salad or forage substitute but to a limited extent. However, extensive research on ampicillin contained in H. radicata has been conducted, and its anticancer and anti-inflammatory effects have been recognized. There are only a few methods to manage H. radicata both culturally and physically. In orchards, soil treatments such as oxyfluorfen and diclobenil, or nonselective foliar treatments such as glufosinate-ammonium and glyphosate are used. Notably, there are no known biological control agents.