• Journal of Microbiology and Biotechnology
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• v.30 no.8
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• pp.1184-1194
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• 2020

Melanin is a major factor that darkens skin color as one of the defense systems to prevent the harmful effects of UV light. However, darkened skin from the localized or systemic accumulation of melanin is viewed in many cultures as an esthetic problem. Consequentially, searching for anti-melanogenic agents from natural sources is very popular worldwide. Previous screening of fermented rice products, obtained from various rice cultivars fermented with different sources of loog-pang (Thai traditional fermentation starter), revealed that the highest ability to reduce the melanin content in B16F10 melanoma cells was from unpolished black rice fermented with a defined starter mixture of microbes isolated from loog-pang E11. The aim of this study was to investigate the mechanism of the fermented unpolished black rice (FUBR) on the inhibition of melanogenesis in B16F10 melanoma cells. The strongest reduction of cellular melanin content was found in the FUBR sap (FUBRS). The melanin reduction activity was consistent with the significant decrease in the intracellular tyrosinase activity. The FUBRS showed no cytotoxic effect to B16F10 melanoma or Hs68 human fibroblast cell lines. It also significantly reduced the transcript and protein expression levels of tyrosinase, tyrosinase-related protein 1 (TYRP-1), TYRP-2, and microphthalmia-associated transcription factor. Furthermore, it induced a significantly increased level of phosphorylated ERK, p38 and Akt signaling pathways, which likely contributed to the negative regulation of melanogenesis. From these results, a model for the mechanism of FUBRS on melanogenesis inhibition was proposed. Moreover, these results strongly suggested that FUBRS possesses anti-melanogenesis activity with high potential for cosmeceutical application as a skin depigmenting agent.

• Korean Journal of Food Science and Technology
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• v.22 no.1
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• pp.105-109
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• 1990

A laboratory scale co-rotating twin-screw extruder (D24 mm, L/D=14) was used for the extrusion of rice, which could be used for a puffed rice snack. As screw speed of the extrusion cooker was increased from 200 to 360 rpm, air cells structure of the extrudate from glutinous rice powder was improved to small and uniform air cells, and the moisture conetent of rice powder should be maintained to 15-17.5% for better texture of the extrudate. Objective and sensory texture of the extrudate from powder was better than those from grits, and there was no significant difference in textural properties between extrusion made with rice and glutinous rice.

• Journal of Digital Convergence
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• v.13 no.2
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• pp.401-406
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• 2015

The aim of present study is to investigate antioxidative effect of the Rice Bran Extracts and Defatted Rice Bran Extracts. Rice Bran Extracts used Rice Bran Water Extract, Rice Bran Ethanol Extract, Defatted Rice Bran Water Extract, Defatted Rice Bran Ethanol Extract. This study was carried out to examine quenching effects of Rice bran extracts on DPPH-, Riboflavin-, and Xanthin oxidase- originated superoxide activities. In addition, in order to determine whether Rice Bran Extract can be safely applied to human skin, the cytotoxic effects of Rice Bran Extract in Human Dermal Fibroblast cells were determined using MTS Assay. These results demonstrated that RBE and DRBE had anti-oxidative properties and did not induce the cytotoxic effects in Human Dermal Fibroblast cells. Therefore, these findings suggest that anti-oxidative properties of RBE and DRBE may be considered convergence with skin care.

• Molecules and Cells
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• v.28 no.5
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• pp.463-472
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• 2009

Although the possible cellular roles of several ubiquitin-specific proteases (UBPs) were identified in Arabidopsis, almost nothing is known about UBP homologs in rice, a monocot model plant. In this report, we searched the rice genome database (http://signal.salk.edu/cgi-bin/RiceGE) and identified 21 putative UBP family members (OsUBPs) in the rice genome. These OsUBP genes each contain a ubiquitin carboxyl-terminal hydrolase (UCH) domain with highly conserved Cys and His boxes and were subdivided into 9 groups based on their sequence identities and domain structures. RT-PCR analysis indicated that rice OsUBP genes are expressed at varying degrees in different rice tissues. We isolated a full-length cDNA clone for OsUBP6, which possesses not only a UCH domain, but also an N-terminal ubiquitin motif. Bacterially expressed OsUBP6 was capable of dismantling K48-linked tetra-ubiquitin chains in vitro. Quantitative real-time RT-PCR indicated that OsUBP6 is constitutively expressed in different tissues of rice plants. An in vivo targeting experiment showed that OsUBP6 is predominantly localized to the nucleus in onion epidermal cells. We also examined how knock-out of OsUBP6 affects developmental growth of rice plants. Although homozygous T3 osubp6 T-DNA insertion mutant seedlings displayed slower growth relative to wild type seedlings, mature mutant plants appeared to be normal. These results raise the possibility that loss of OsUBP6 is functionally compensated for by an as-yet unknown OsUBP homolog during later stages of development in rice plants.

• Korean Journal of Weed Science
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• v.16 no.1
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• pp.42-53
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• 1996

The tolerant and susceptible rice cultivars to oxyfluorfen were selected from 400 rice cultivars in a laboratory, and tested in comparison with barnyardgrass, a typical oxyfluorfen susceptible weed. The responses to oxyfluorfen in the different levels of calli, cells and protoplasts of the rice cultivars were investigated. $I_{50}$ value of the tolerant rice cultivars was about $10^{-4}M$, whereas that of the susceptible rice cultivars and barnyardgrass was about $10^{-6}M$, showing significant difference between the two groups. The growth rate of calli segregated from the tolerant rice cultivars was higher than that from the susceptible rice cultivars and barnyardgrass by treatment of oxyfluorfen to the calli. The growth rate of suspension-cultured cells of the tolerant rice cultivars was higher than that of the susceptible rice cultivars and barnyardgrass after treatment of oxyfluorfen. The viability of protoplasts from the tolerant rice cultivars was higher than that from the susceptible rice cultivars and barnyardgrass after one or two hours of oxyfluorfen treatment. The intactness of protoplasts from the tolerant rice cultivars was also higher than that form the susceptible rice cultivars and barnyardgrass.

• Journal of Plant Biology
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• v.38 no.1
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• pp.55-62
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• 1995

Embryogenic cell (EC) suspension cultures derived from mature seed-embryo of rice (Oryza sativa L cv. Kye Hwa) were used for the expression patterns of isozyme and enzyme activity. EC suspension cultures were composed of cells that were densely cytoplasmic, potentially embryogenic. However, nonembryogenic cell (NEC) cultures were composed of large, elongated and vacuolated cells. These cells were analyzed for the isozyme pattern and enzyme activity of EC and NEC. Isozyme patterns of peroxidase, esterase, acid phosphatase and malate dehydrogenase exhibited striking difference in the total number of bands, specificity and intensity of band. Also, these isozymes showed very high activity in the EC. Specific band, band activity and higher enzyme activity of isozyme in EC was absent or low in NEC, which may indicate an association of these specific isozymes with morphological characterization and totipotency of embryogenic cells. These results indicate that specific pattern and activity of enzyme in EC could probably be used as a biochemical marker of EC in rice.n rice.

• YAKHAK HOEJI
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• v.58 no.3
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• pp.151-157
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• 2014

Water extracts of rice grasshopper (Oxya japonica japonica Thurnberg) were prepared and their antitumor and immunostimulatory activities were investigated using a flow cytometer. When LCT-CT was ip injected into ICR mice at the dose of 33.3 mg/kg before and after the implantation of $4{\times}10^5$ cells/mouse of sarcoma 180 tumor cells, it inhibited the growth of the tumor cells by 96.6%, showed lymphoblstogenic activities on the splenic lymphocytes and increased the expression of CD25 molecules on the splenic T lymphocytes. When co-cultured with the splenic lymphocytes of a BALB/c mouse, LCT-CT showed strong immunostimulatory activities at the concentration of $25{\sim}100{\mu}g/ml$ by significantly increasing lymphoblasts ratio and CD25 expression.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4601-4607
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• 2014

Red rice contains pharmacological substances including phenolics, oryzanol, tocotrienol and tocopherol. Recently, red rice extract has been employed as a source of antioxidants for inhibition of tumor growth. This study was carried out to evaluate the anti-invasion effects of red rice extract fractions on cancer cells. It was found that at $100{\mu}g/ml$ of crude ethanolic extract (CEE), hexane fraction (Hex) and dichloromethane fraction (DCM) could reduce HT1080 and MDA-MB-231 cancer cell invasion. Hex and DCM revealed higher potency levels than CEE, whereas an ethyl acetate fraction (EtOAc) had no effect. Gelatin zymography revealed that Hex decreased the secretion and activity of matrix metalloproteinase-2 and -9 (MMP-2 and-9). In contrast, the DCM fraction exhibited slightly effect on MMPs secretion and had no effect on MMPs activity. Collagenase activity was significantly inhibited by the Hex and DCM fractions. High amounts of ${\gamma}$-oryzanol and ${\gamma}$-tocotrienol were found in the Hex and DCM fractions and demonstrated an anti-invasion property. On the other hand, proanthocyanidin was detected only in the CEE fraction and reduced MDA-MB-231 cells invasion property. These observations suggest that proanthocyanidin, ${\gamma}$-oryzanol and ${\gamma}$-tocotrienol in the red rice fractions might be responsible for the anti invasion activity. The red rice extract may have a potential to serve as a food-derived chemotherapeutic agent for cancer patients.

• The Plant Pathology Journal
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• v.28 no.2
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• pp.164-171
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• 2012

Rice blast disease caused by Magnaporthe grisea (Hebert) Barr [teleomorph] is one of the most devastating diseases in rice plantation areas. Silicon is considered as a useful element for a large variety of plants. Rice variety MR219 was grown in the glasshouse to investigate the function of silicon in conferring resistance against blast. Silica gel was applied to soil while sodium silicate was used as foliar spray at the rates of 0, 60, 120, 180 g/5 kg soil and 0, 1, 2, 3 ml/l respectively. The treatments were arranged in a completely randomized design. Disease severity and silicon content of leaves were compared between the non-amended controls and rice plants receiving the different rates and sources of silicon. Silicon at all rates of application significantly (${\alpha}$ = 0.05) reduced the severity of disease with highest reduction (75%) recorded in treatments receiving 120 g of silica gel. SEM/EDX observations demonstrated a significant difference in weight concentration of silicon in silica cells on the leaf epidermis between silicon treated (25.79%) and non treated plants (7.87%) indicating that Si-fertilization resulted in higher deposition of Si in silica cells in comparison with non-treated plants. Application of silicon also led to a significant increase in Si contents of leaves. Contrast procedures indicated higher efficiency of silica gel in comparison to sodium silicate in almost all parameters assessed. The results suggest that mitigated levels of disease were associated with silicification and fortification of leaf epidermal cells through silicon fertilization.

• Korean Journal of Weed Science
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• v.14 no.2
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• pp.128-143
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• 1994

At 5 DAS/T, leaf primordia of rice stems that were grown under dry condition in transverse sections were strongly stained while those under water condition had many aerenchyma cells well developed. On the other hand, leaf primordia and large air spaces in stem of transplanted rice were well developed. Rice in leaf anatomy had small and fine epidermal cells, chlorophyllous mesophylls, and bulliform cells but had no chlorophyllous vascular bundle sheath cells, while barnyardgrass leaf had large, rough and irregularly arranged epidermal cells, chlorophyllous vascular bundle sheath cells, and non-bulliform cells but had no chlorophyllous mesophylls. Epidermal cells of transplanted rice, however, were well developed, differentiated and sclerified. Cross sections of rice root under dry condition showed cell contents, regularly arranged cells, non-intercellular spaces and non-aerenchyma while under water condition had well-developed intercellular spaces, aerenchyma cells, small and densely arranged epidermis, sclerified exodermis and sclerenchyma cells. But root anatomy of transplanted rice consisted of finely, regularly arranged epidermis, well-developed intercellular spaces and nucleous cells.