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Organic fertilizers were applied in four different forms: mixed organic matter, fermentation cake, bacterial culture, and rice husks, excluding conventional chemical fertilizer and non-treatment used as control. The results showed that soil pH was acidified after fermentation cake and chemical fertilizer treatment. Specifically, chemical fertilizer treatment showed higher phosphoric-acid content than other treatments, while total N content was higher in fermentation cake, mixed organic matter and chemical fertilizer. Growth of Codonopsis lanceolata showed superior tendency in the treatment of mixed organic matter and fermentation cake. Lancemacides, the major saponin of C. lanceolata, could be identified as foetidissimoside A, lancemaside A, lancemaside B, and lancemaside D. However, among them, quantitative analysis could not be conducted on foetidissimoside A due to its very low content, and lancemaside A was the most abundant saponin in the root from all the treatments. The content of lancemaisde A according to organic fertilizer application showed the highest value of 0.12 mg g−1 in the treatment of mixed organic matter, followed by the fermentation cake, bacterial culture, non-treatment, rice husks and chemical fertilizer, in that order. The content of lancemaside B and D was very low compared to lancemaside A, and there was no difference among treatments. Therefore, it was verified that the growth of C. lanceolata was superior in application of mixed organic matter and fermentation cake, and the major saponin, lancemaside A, was also increased.

The levels of major bioactive compounds, such as amino acids and antioxidants, were investigated in okra sprouts and seeds of the varieties ‘Green Sword’ and ‘Benny’. Total polyphenol content was the highest in ‘Benny’ cotyledons, followed by ‘Benny’ hypocotyls and ‘Green Sword’ cotyledons. Polyphenol and flavonoid content in the two varieties were approximately 5- to 6-fold higher in sprouts than in seeds, and were higher in the cotyledons than in other tissues within the sprout. Activity of the radical scavenger DPPH was the highest in ‘Benny’ cotyledons, and mean values were 7.3-fold higher in sprouts than in seeds. Total amino acid content in both varieties was the highest in hypocotyls, followed by cotyledons and seeds. This content was about 40-fold higher in hypocotyls than in seeds. Alanine and Glycyrrhizin were the most abundant amino acids. Total vitamin C content was the highest in ‘Benny’ cotyledons, followed by ‘Green Sword’ cotyledons, and the lowest in hypocotyls of both varieties. In ‘Green Sword’ seeds, the levels of vitamins B1, B3, B5, and B6 were higher than the levels of B2 and B9. In ‘Benny’, B1 and B3 content were higher in the cotyledon, while B2, B5, and B9 content were higher in the hypocotyl. This study demonstrates the potential of okra sprouts to be used as a functional food ingredient and as a source of antioxidants.

Background: Immature fruit of Rubus coreanus, also known as “Bokbunja” in Korea, have been used as traditional medicinal plant in East-Asia. Although several studies have been conducted to the fruit composition of R. coreanus, research on the antioxidant composition of branch and leaves are limited. Objectives: We aimed to analyze the contents of five antioxidants in leaves and branches of R. coreanus using different extraction method. Materials and Methods: R. coreanus were cultivated at the research farm of the Gyeongsang National University. R. coreanus plants were harvested in May and July, and leaf and branch extracts were prepared using the ultrasonic bath and reflux extraction methods and analyzed using liquid chromatography-tandem mass spectrometry. Results: The ultrasonic bath extraction method extracted 7.1 and 1.5 mg/100 g gallic acid from leaves and branches, respectively, whereas the reflux extraction method yielded 12.4 and 16.5 mg/100 g, respectively. Thus, reflux extraction was superior to ultrasonic bath for both leaf and branch parts. In the extracts prepared by reflux extraction, contents of all five compounds were higher in leaves than in branches. In leaves extracted with the reflux extraction method, ellagic acid was the most abundant, followed by quercetin-3-O-glucoside (24.7 mg/100 g), gallic acid (12.4 mg/100 g), quercetin (7.3 mg/100 g), and kaempferol (1.5 mg/100 g). Contents of all compounds were higher in May (1.1 mg/g) than in July (0.7 mg/g). Conclusion: R. coreanus plant was identified to show antioxidant activity and to present abundantly five antioxidants not only in fruit but also in leaves and branches in May. Specially, quercetin was three-fold higher in leaves than in fruit juice.

The bacterial pathogen Pantoea sp. strain PPE7 causes severe soft rot disease in the king oyster mushroom, Pleurotus eryngii. Typical symptoms of the disease include a dark-brown water drop at early stages of infection, ultimately leading to soft rot accompanied with an offensive odour. In this study, we showed that inoculation of Flammulina velutipes and Agaricus bisporus mushrooms with Pantoea sp. strain PPE7 also resulted in severe disease, including water-soaked lesions and soft rot symptoms. Treatment with chlorine solution (175 to 700 ppm active chlorine) significantly reduced the incidence of soft rot symptoms in Pleurotus eryngii. However, exposure to concentrations greater than 350 ppm caused harmful effects such as bleaching on the cap of the fruit body. Calcium hypochlorite solutions with 175 ppm active chlorine were effective for reducing soft rot disease of Pleurotus eryngii without affecting the mushroom yield.

Chlorophyll (Chl) fluorescence analysis was used to assess stress tolerance in wild and cultivated strawberry species. We found that the parameters, photochemical quenching (1-qP), non-photochemical quenching (qN), and maximum quantum yield (Fv/Fm), can serve as stress indicators because they are sensitive to early responses to stress. The most sensitive region used for measuring Chl fluorescence in strawberry leaves was the upper surfaces of leaflets located in the middle of new leaves. An analysis of the Chl fluorescence characteristics of strawberry species showed that octoploid species had greater stress tolerance than diploid species. The ‘Whiteberry’ maintained high levels of 1-qP and qN through the dissipation of excess excitation energy as heat during early stress treatment. These results suggest that ‘Whiteberry’ has a photoinhibition system that allows it to respond to stress in a more sensitive manner than other cultivars. Therefore, among the Chl fluorescence parameters examined, 1-qP and qN, can serve as good indicators for comparing stress tolerance, and they can be used to simultaneously screen many plants for stress tolerance in strawberry breeding programs.

The leaves of Stevia rebaudiana Bertoni have attracted much attention as a source of natural sweeteners. This study was conducted to investigate the natural sweeteners contents and analyze antioxidant materials and activity according to harvest times and extraction methods in stevia.Stevia leaves were extracted using 5 extraction methods to identify the extraction with high extraction efficiency. Extraction yield was high in the order of hot water extraction (HWE), reflux extraction (RE), high temperature and pressure extraction (HTPE), ultrasonic extraction (UE) and vacuum extraction (VE). The contents of rebaudioside A and stevioside in stevia leaves had the highest in HTPE. Also, the total phenolic and flavonoid contents had the highest in HTPE and VE. Using the HTPE method, the result analyzed that the contents of rebaudioside A and stevioside of stevia leaves harvested between April and October exhibited the tendency to increase gradually between July and October. HTPE is considered to be an appropriate method for extracting stevia leaves. Also, it was confirmed that the stevia leaves of July, September and October, except for the high temperature period of August, had superior in quality and quantity.