• Natural Product Sciences
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• v.21 no.3
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• pp.170-175
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• 2015

The present study aims to detect the rare flavonoids isolated from the leaves of Persicaria glabra. The known flavonoids: quercetin (1), isorhamnetin (2), avicularin (3) and new one isorhamnetin-3-O-α-L-(6''-E-p-coumaroyl)-rhamnoside (4) were identified by HPLC, UV, IR and NMR. P. glabra has used traditionally for its analgesic, anti-inflammatory and anti-rheumatic properties. To find out the ingredients responsible for the efficiency of this plant, we have used to study the anti-microbial and anti-inflammatory activities of different extracts.

• Environmental Engineering Research
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• v.15 no.3
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• pp.157-161
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• 2010

Forest soils are often nitrogen-limited, and nitrogen input to forest soils can cause substantial changes in the structure and functions of a soil ecosystem. To determine the effects of nitrogen input on methane oxidation and the microbial enzyme activities, manipulation experiments were conducted using nitrogen addition to soil samples from Mt. Jumbong. Our findings suggested that the addition of nitrogen to the soil system of Mt. Jumbong did not affect the microbial enzyme activities. Conversely, the addition of nitrogen affected the rate of methane oxidation. Inorganic nitrogen in soils can inhibit methane oxidation via several mechanisms, such as substrate competition, toxic effects, and competition with other microbes, but the inhibitory effects are not always the same. In this research, seasonal changes were found to produce different inhibitory factors, and these different responses may be caused from differences in the methantrophic bacteria community structure.

• Natural Product Sciences
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• v.25 no.2
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• pp.92-102
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• 2019

Centella asiatica (Linn.) Urban (Umbelliferae) which is also known as 'pegaga' is highly consumed and eaten raw as 'ulam' in Malaysia. C. asiatica is used in traditional medicines to treat various health conditions such as rheumatism, inflammation, syphilis, skin diseases and diarrhoea. Various reports exhibited that the crude extracts and isolated bioactive compounds of C. asiatica possessed a broad range of pharmacological activities such as anti-oxidant, anti-diabetic, anti-tumor, wound healing, anti-microbial, anti-inflammatory, immunomodulatory, hepatoprotective and memory enhancing properties. The pharmacological validation on anti-microbial and immunomodulatory of C. asiatica is very limited and several existence review papers related for this plant had not been focused for both activities. This review therefore attempts to combine the existing literature to offer immense scope for researchers engaged in validation of the traditional claims and bioactivities of this plant related with anti-microbial and immunomodulatory potential.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.4
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• pp.262-270
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• 2015

The scientific information between microbial community and chemical properties of reclaimed tidal soil is not enough to understand the land reclamation process. This study was conducted to investigate the relation between chemical properties and microbial activities of soils from reclaimed tidal lands located at south-western coastal area (42 samples from Goheuong, Samsan, Bojun, Kunnae, Hwaong and Yeongsangang sites). Most of the reclaimed soils showed chemical characteristics as salinity soil based on EC. Only $Na^+$ in exchangeable cation was dependent on EC of reclaimed soil, whereas other cations such as $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were independent on EC. The mesophilic bacteria decreased with an increase in EC of soil. Microbial population increased with soil organic content in the range of $0{\sim}10g\;kg^{-1}$ and dehydrogenase activity less than $100{\mu}g-TPF\;g^{-1}h^{-1}$. Microbial population of soils from reclaimed tidal lands was closely related to the microbial community containing hydrolytic enzyme activities of cellulase, amylase, protease, and lipase.

• Korean Journal of Environmental Agriculture
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• v.27 no.2
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• pp.139-144
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• 2008

A field experiment was conducted to investigate the influence of cultivars and compost on soil microbial activities and diversities in a red pepper-grown field. Compost was applied with 0, 30, and 60M/T $ha^{-1}$ in April and then red pepper seedlings of "Yong-go 4" and "Koeun" were transplanted in May 2007. Soil samples were collected in early August 2007. Measurement of microbial activities was based on a dehydrogenase assay and a fluorescein diacetate hydrolysis. Soil microbial community was characterized with Biolog $EcoPlate^{TM}$ and phospholipid fatty acid(PLFA). Red pepper cultivars did not differentiate the selected soil chemical and microbial properties. Soil pH and soil microbial community changed by amending the soil with 30 and 60 M/T $ha^{-1}$ of compost, and the soil organic matter and potassium content, and soil microbial activities increased in soils amended with 60 M/T $ha^{-1}$ of compost. Red pepper cultivar induced a little different soil chemical properties and microbial activity in soils amended with 60 M/T $ha^{-1}$ of compost even though significant differences were not found in those properties. In conclusion the effects of compost on soil chemical and microbial properties were much higher than red pepper cultivars in short-term period but the effects of red pepper cultivars should be investigated in long-term field test.

• Journal of Marine Life Science
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• v.8 no.1
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• pp.56-67
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• 2023

Marine macroalgae are important in coastal ecosystems and interact with marine microorganisms. In this study, we isolated fungi from seven types of marine macroalgae including Cladophora sp., Gloiopeltis furcate, Gracilariopsis chorda, Hydroclathrus clathratus, Prionitis crispata, Sargassum micracanthum, and Ulva lactuca collected in Korea. Morphological and phylogenetic analyses identified the isolates as four Aspergillus spp. (A. fumigatus, A. sydowii, A. tamarii, and A. terreus), three Penicillium spp. (P. crustosum, P. jejuense, and P. rubens), and Cladosporium tenuissimum. Among them, A. fumigatus TOP-U2, A. tamarii SH-Sw5, and A. terreus GJ-Gf2 strains showed the activities of all enzymes examined (amylase, chitinase, lipase, and protease). Based on the enzymatic index (EI) values in solid media, A. terreus GJ-Gf2 and C. tenuissimum UL-Pr1 exhibited the highest amylase and lipase activities, respectively. Chitinolytic activity was only observed in A. terreus GJ-Gf2, A. tamarii SH-Sw5, and A. fumigatus TOP-U2. Penicillium crustosum UL-Cl2 and C. tenuissimum UL-Pr1 showed the highest protease activities. To the best of our knowledge, this is the first report of lipolytic and proteolytic activities in a marine-derived C. tenuissimum strain. Overall, the fungal strains isolated from the marine macroalgae in this study actively produced industrially important enzymes.

• Journal of Microbiology
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• v.42 no.4
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• pp.267-277
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• 2004

Effects of elevated $CO_2$ on soil microorganisms are known to be mediated by various interactions with plants, for which such effects are relatively poorly documented. In this review, we summarize and syn­thesize results from studies assessing impacts of elevated $CO_2$ on soil ecosystems, focusing primarily on plants and a variety the of microbial processes. The processes considered include changes in microbial biomass of C and N, microbial number, respiration rates, organic matter decomposition, soil enzyme activities, microbial community composition, and functional groups of bacteria mediating trace gas emission such as methane and nitrous oxide. Elevated $CO_2$ in atmosphere may enhance certain micro­bial processes such as $CH_4$ emission from wetlands due to enhanced carbon supply from plants. How­ever, responses of extracellular enzyme activities and microbial community structure are still controversy, because interferences with other factors such as the types of plants, nutrient availabilitial in soil, soil types, analysis methods, and types of $CO_2$ fumigation systems are not fully understood.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.487-493
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• 2013

The effects of long-term fertilization on soil biological properties and microbial community structure in the plough layer in a rice paddy soil in southern Korea were investigated in relation to the continuous application of chemical fertilizers (NPK), straw based compost (Compost), combination these two (NPK + Compost) for last 40 years. No fertilization plot (Control) was installed for comparison. Though fertilization significantly improved rice productivity over control, the long-term fertilization of NPK and compost combination was more effective on increasing rice productivity and soil nutrient status than single application of compost or chemical fertilizer. All fertilization treatments had shown significant improvement in soil microbial properties, however, continuous compost fertilization markedly increased soil enzyme and microbial activities as compared to sole chemical fertilization. Results of microbial community structure, evaluated by EL-FAME (ester-linked fatty acid methyl esters) method, revealed big difference among Control, NPK, and Compost. However, both Compost and Compost+NPK treatments belonged to the same cluster after statistical analysis. The combined application of chemical fertilizer and organic amendments could be more rational strategy to improve soil nutrient status and promote soil microbial communities than the single chemical fertilizer or compost application.

• Journal of Microbiology and Biotechnology
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• v.33 no.6
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• pp.760-770
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• 2023

Continuous cropping obstacles have become a serious factor restricting sustainable development in modern agriculture, while companion planting is one of the most common and effective methods for solving this problem. Here, we monitored the effects of companion planting on soil fertility and the microbial community distribution pattern in pepper monoculture and companion plantings. Soil microbial communities were analyzed using high-throughput sequencing technology. Companion plants included garlic (T1), oat (T2), cabbage (T3), celery (T4), and white clover (T5). The results showed that compared with the monoculture system, companion planting significantly increased the activities of soil urease (except for T5) and sucrase, but decreased catalase activity. In addition, T2 significantly improved microbial diversity (Shannon index) while T1 resulted in a decrease of bacterial OTUs and an increase of fungal OTUs. Companion planting also significantly changed soil microbial community structures and compositions. Correlation analysis showed that soil enzyme activities were closely correlated with bacterial and fungal community structures. Moreover, the companion system weakened the complexity of microbial networks. These findings indicated that companion plants can provide nutrition to microbes and weaken the competition among them, which offers a theoretical basis and data for further research into methods for reducing continuous cropping obstacles in agriculture.

• Journal of Ecology and Environment
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• v.34 no.4
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• pp.401-410
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• 2011

We assayed the effects of simulated acid rain on the mass loss, $CO_2$ evolution, dehydrogenase activity, and microbial biomass-C of decomposing Sorbus alnifolia leaf litter at the microcosm. The dilute sulfuric acid solution composed the simulated acid rain, and the microcosm decomposition experiment was performed at 23$^{\circ}C$ and 40% humidity. During the early decomposition stage, decomposition rate of S. alnifolia leaf litter, and microbial biomass, $CO_2$ evolution and dehydrogenase activity were inhibited at a lower pH; however, during the late decomposition stage, these characteristics were not affected by pH level. The fungal component of the microbial community was conspicuous at lower pH levels and at the late decomposition stage. Conversely, the bacterial community was most evident during the initial decomposition phase and was especially dominant at higher pH levels. These changes in microbial community structure resulting from changes in microcosm acidity suggest that pH is an important aspect in the maintenance of the decomposition process. Litter decomposition exhibited a positive, linear relationship with both microbial respiration and microbial biomass. Fungal biomass exhibited a significant, positive relationship with $CO_2$ evolution from the decaying litter. Acid rain had a significant effect on microbial biomass and microbial community structure according to acid tolerance of each microbial species. Fungal biomass and decomposition activities were not only more important at a low pH than at a high pH but also fungal activity, such as $CO_2$ evolution, was closely related with litter decomposition rate.