• Animal Bioscience
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• v.34 no.3_spc
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• pp.345-353
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• 2021

Phytobiotics, also known as phytochemicals or phytogenics, have a wide variety of biological activities and have recently emerged as alternatives to synthetic antibiotic growth promoters. Numerous studies have reported the growth-promoting effects of phytobiotics in chickens, but their precise mechanism of action is yet to be elucidated. Phytobiotics are traditionally known for their antioxidant activity. However, extensive investigations have shown that these compounds also have anti-inflammatory, antimicrobial, and transcription-modulating effects. Phytobiotics are non-nutritive constituents, and their bioavailability is low. Nonetheless, their beneficial effects have been observed in several tissues or organs. The health benefits of the ingestion of phytobiotics are attributed to their antioxidant activity. However, several studies have revealed that not all these benefits could be explained by the antioxidant effects alone. In this review, I focused on the bioavailability of phytobiotics and the possible mechanisms underlying their overall effects on intestinal barrier functions, inflammatory status, gut microbiota, systemic inflammation, and metabolism, rather than the specific effects of each compound. I also discuss the possible mechanisms by which phytobiotics contribute to growth promotion in chickens.

• The Plant Pathology Journal
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• v.38 no.5
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• pp.490-502
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• 2022

Xanthomonas oryzae pv. oryzae (Xoo) causes bacterial leaf blight (BLB) disease in rice (Oryza sativa L.) and it is among the most destructive pathogen responsible for severe yield losses. Potential bacterial biocontrol agents (BCAs) with plant growth promotion (PGP) abilities can be applied to better manage the BLB disease and increase crop yield, compared to current conventional practices. Thus, this study aimed to isolate, screen, and identify potential BCAs with PGP abilities. Isolation of the BCAs was performed from internal plant tissues and rhizosphere soil of healthy and Xoo-infected rice. A total of 18 bacterial strains were successfully screened for in vitro antagonistic ability against Xoo, siderophore production and PGP potentials. Among the bacterial strains, 3 endophytes, Bacillus sp. strain USML8, Bacillus sp. strain USML9, and Bacillus sp. strain USMR1 which were isolated from diseased plants harbored the BCA traits and significantly reduced leaf blight severity of rice. Simultaneously, the endophytic BCAs also possessed plant growth promoting traits and were able to enhance rice growth. Application of the selected endophytes (BCAs-PGP) at the early growth stage of rice exhibited potential in suppressing BLB disease and promoting rice growth.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1250-1258
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• 2009

Bacillus spp., as a type of plant growth-promoting rhizobacteria (PGPR), were studied with regards promoting plant growth and inducing plant systemic resistance. The results of greenhouse experiments with tobacco plants demonstrated that treatment with the Bacillus spp. significantly enhanced the plant height and fresh weight, while clearly lowering the disease severity rating of the tobacco mosaic virus (TMV) at 28 days post-inoculation (dpi). The TMV accumulation in the young non-inoculated leaves was remarkably lower for all the plants treated with the Bacillus spp. An RT-PCR analysis of the signaling regulatory genes Coil and NPR1, and defense genes PR-1a and PR-1b, in the tobacco treated with the Bacillus spp. revealed an association with enhancing the systemic resistance of tobacco to TMV. A further analysis of two expansin genes that regulate plant cell growth, NtEXP2 and NtEXP6, also verified a concomitant growth promotion in the roots and leaves of the tobacco responding to the Bacillus spp.

• Research in Plant Disease
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• v.22 no.4
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• pp.284-288
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• 2016

A plant growth promoting rhizobacterium, Bacillus vallismortis BS07M, was formulated as a clay pellet (CP) to evaluate its pepper growth promotion and induced resistance against various diseases under field and storage conditions. Peppers were grown in 50-hole tray containing potting mixture with CP in seedling raising stage, and then it was transplanted into a field. After transplanting, pepper plants treated with CP in seedling raising stage increased shoot growth and reduced disease severity caused by Phytophthora capsici in detached pepper leaves compared to untreated control. Moreover, treatment with CP in seedling raising stage increased fruit weight per plant; after harvesting, pepper fruits shown reduced diameter of lesions by Colletotrichum acutatum, and occurrance of soft rot in storage condition. These results indicated that CP could affect plant growth and induced resistance in pepper plants under field condition, and maintenance of fruit during storage.

• Journal of Microbiology and Biotechnology
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• v.25 no.8
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• pp.1349-1360
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• 2015

The rhizospheric zone abutting plant roots usually clutches a wealth of microbes. In the recent past, enormous genetic resources have been excavated with potential applications in host plant interaction and ancillary aspects. Two Pseudomonas strains were isolated and identified through 16S rRNA and rpoD sequence analyses as P. fluorescens QAU67 and P. putida QAU90. Initial biochemical characterization and their root-colonizing traits indicated their potential role in plant growth promotion. Such aerobic systems, involved in gluconic acid production and phosphate solubilization, essentially require the pyrroloquinoline quinine (PQQ)-dependent glucose dehydrogenase (GDH) in the genome. The PCR screening and amplification of GDH and PQQ and subsequent induction of mutagenesis characterized their possible role as antioxidants as well as in growth promotion, as probed in vitro in lettuce and in vivo in rice, bean, and tomato plants. The results showed significant differences (p ≤ 0.05) in parameters of plant height, fresh weight, and dry weight, etc., deciphering a clear and in fact complementary role of GDH and PQQ in plant growth promotion. Our study not only provides direct evidence of the in vivo role of GDH and PQQ in host plants but also reveals their functional inadequacy in the event of mutation at either of these loci.

• Journal of Life Science
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• v.28 no.6
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• pp.663-670
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• 2018

This study was performed to confirm the antioxidative and hair-growth-promotion effects of a fermented compound composed of five materials, namely Allium cepa, Cucurbita spp., Glycine max Merr., Pinus sylvestris leaf, and Sesamum indicum. An additional compound composed of two materials was composed of Allium cepa and Cucurbita spp. Antioxidative effects were measured based on DPPH radical-scavenging activity and total flavonoid content. Fermented 5-type natural compounds (5NC) showed higher DPPH radical-scavenging activity and flavonoid content than those of fermented 2-type natural compounds (2NC). Hair-growth promotion was demonstrated in vivo. Alkaline phosphatase (ALP), oid contentontenteptidase phospactivity, and macroscopic observation were measured. Experimental animals were divided into four groups based on the samples they were administered: water, pansildil (P-CON), 5NC, and 2NC. Samples were administered orally once a day at a fixed time for four weeks. Both ALP and ${\gamma}eeksactivity$ increased in the 5NC group compared with the 2NC group. In macroscopic observation, the P-CON group grew the most and were most similar to the state before shaving. The 5NC group grew hair similar to the P-CON group. In all the results, the 5NC group showed greater antioxidative and hair-growth-promotion effects than the 2NC group. Consequently, 5NC could be used as an ingredient for hair-growth promotion.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.190-190
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• 2017

Chemical fertilizers have been used to increase crop production and contributed to escaping food shortages. However, excessive use of chemical fertilizers over a long period caused many problems such as environmental pollution and the hampered production potential of the land. Thus, it is necessary to develop eco-friendly bio-fertilizers that can replace the use of chemical fertilizers. Here, we tested the effect of some nitrogen-fixing microorganims on the plant growth promotion. Seventy free-living nitrogen fixing microorganisms were isolated from rhizosphere of crop cultivation fields, streamside soils and sludge in Ansung, Korea. Of them, three strains (NF2-4-1, Yeast; EMM409, Mesorhizobium; Gsoil662, Burkholderia) were selected to be most efficient in the capacity of N-fixing nitrogen based on colony forming cell assay in N-free media. To investigate the ability to promote plant growth, these strains were inoculated into the soil and cabbage were grown for 4 weeks in the grown chamber. Fresh weight, dry weight, and leaf area were measured from 4-week-old plants. Phenotypic analysis revealed that the growth of the plants inoculated with NF2-4-1 and EMM409 strains were significantly promoted compared to the mock-treated control plants, while Gsoil662-inoculated plants did not show statically significant promotion. These results indicate that these nitrogen-fixing microorganims can be used to develop plant growth promoting bio-fertilizers. Further analysis on nitrogen fixing level in soil by these strains will be tested.

• Korean Journal of Organic Agriculture
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• v.22 no.2
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• pp.321-334
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• 2014

This study was conducted to identify plant growth promoting effects of native plant resources and medicinal plants. 65 kinds of plant extracts from 64 species were evaluated based on two rice(Oryza sativa) seedling bioassays for gibberellins and gibberellin-like substances. 12 extracts of Artemisia princeps stem and leaf, Cirsium japonicum var. maackii whole plant, Rhododendron mucronulatum branch and leaf, Phragmites communis stem, Coix lacryma-jobi var. mayuen whole plant, Lespedeza bicolor branch and leaf, Hydrangea serrata f. acuminata whole plant, Phlomis umbrosa whole plant, Glycyrrhiza uralensis Rhizome, G. uralensis stem and leaf, Angelica gigas root, and Cnidium officinale rhizome showed growth promotion of rice seedlings. Our results suggested that the parts of these plants could be the potential sources as farm-made liquid fertilizers for plant growth promotion.

• Biomolecules & Therapeutics
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• v.21 no.5
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• pp.323-331
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• 2013

TGF-${\beta}$ pathway is being extensively evaluated as a potential therapeutic target. The transforming growth factor-${\beta}$ (TGF-${\beta}$) signaling pathway has the dual role in both tumor suppression and tumor promotion. To design cancer therapeutics successfully, it is important to understand TGF-${\beta}$ related functional contexts. This review discusses the molecular mechanism of the TGF-${\beta}$ pathway and describes the different ways of tumor suppression and promotion by TGF-${\beta}$. In the last part of the review, the data on targeting TGF-${\beta}$ pathway for cancer treatment is assessed. The TGF-${\beta}$ inhibitors in pre-clinical studies, and Phase I and II clinical trials are updated.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.10b
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• pp.47-47
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• 2003

Plant growth promoting rhizobacteria (PGPR) have been shown to suppress phytopthora blight. This suppression has been related to both microbial antagonism and induced resistance. The PGPR isolates were screened by dual culture plate method and most of the isolates were showed varyinglevels of antagonism. Among the PGPR isolates pyoverdin, pyochelin and salicylic acid producing strains showed the maximum inhibition of mycelial growth of Phytophthora capsici and increased plant growth promotion in red pepper. PGPR isolatesfurther analysed for its ability to induce production of defence related enzymes and chemicals. The activities such as Phenyle alanin ammonia lyase (PAL), Peroxidase (PO), Polyphenol oxidase (PPO) and accumulation of phenolics were observed in PGPR pretreated red pepper plants challenged with Phytophthora capsici. The present study shows that an addition of direct antagonism and plant growth promotion, induction of defense related enzymes involved to enhance resistance against invasion of P. capsici in red pepper.