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Rice Hull (rice + hull)

Distribution by Scientific Domains
Chemistry80%

Selected Abstracts

New Stigmastane Steroids Constituents from Rice Hulls of Oryza sativa and Inhibitory Activity on Radish Seed

CHEMINFORM, Issue 21 2006
Ill-Min Chung
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]

Simultaneous wet ball milling and mild acid hydrolysis of rice hull

JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 1 2010
Jinxiang Zhou
Abstract BACKGROUND: Rice hull, an abundant residue but a big issue for the rice processing industry, has the potential to serve as a feedstock for production of ethanol because of its lignocellulosic composition. Simultaneous wet ball milling and mild acid hydrolysis of rice hull was studied in this work. RESULTS: Ball milling with 150 small stainless steel beads and rotation speed of 600 rpm in citrate solvent of pH 4 was the optimal condition for hydrolysis, and the yield of sugar increased with increased milling time. Corresponding structure transformations before and after milling analyzed by X-ray diffraction (XRD), environmental scanning electron microscopy (ESEM) and transmission fourier transform infrared spectroscopy (FT-IR) clearly indicate that this hydrolysis could be attributed to the crystalline and chemical structure changes of cellulose in rice hull during ball milling in mild acid solvent. CONCLUSION: This combined treatment of ball milling and citrate solvent greatly changed the crystalline and chemical structure and continuously generated sites accessible to citrate solvent, thus enabling hydrolysis of the rice hull. Copyright © 2009 Society of Chemical Industry [source]

Allelochemical tricin in rice hull and its aurone isomer against rice seedling rot disease

PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 9 2010
Chui-Hua Kong
Abstract BACKGROUND: One promising area of rice disease management is the potential of exploiting biological control agents. Rice seedling rot disease caused by soil-borne pathogenic fungi has become a dominant disease problem because of greater use of direct seeding. Rice hull has been potentially used to control paddy weeds, but little information is available on rice disease. This study was conducted to investigate the relationships between disease incidence and soil amended with tricin-releasing rice hull, and to assess fungicidal activity of tricin and its synthesised aurone isomer, with an attempt to develop an allelochemical-based fungicide against rice seedling rot disease. RESULTS: Tricin was detected in all hulls of 12 rice cultivars tested, but its contents in rice hulls varied greatly with the cultivar and genotype. Tricin in rice hulls was released into the soil once amended. Disease incidence was significantly reduced by soil amended with rice hull. Tricin-rich rice hull amendment greatly suppressed soil-borne pathogenic fungi Fusarium oxysporum Schlecht. and Rhizoctonia solani Kühn which cause rice seedling rot disease. In attempting to obtain enough tricin for further experiments, the aurone isomer (5,7,4,-trihydroxy-3,,5,-dimethoxyaurone) of tricin rather than tricin itself was unexpectedly synthesised. This aurone isomer had much stronger fungicidal activity on both F. oxysporum and R. solani than tricin itself. CONCLUSION: Soil amended with tricin-rich rice hull was associated with reduced risk of developing seedling rot disease. The tricin isomer, aurone, is more effective against rice seedling rot disease than tricin itself, making it an ideal lead compound for new fungicide discovery. Copyright © 2010 Society of Chemical Industry [source]

Simultaneous wet ball milling and mild acid hydrolysis of rice hull

JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 1 2010
Jinxiang Zhou
Abstract BACKGROUND: Rice hull, an abundant residue but a big issue for the rice processing industry, has the potential to serve as a feedstock for production of ethanol because of its lignocellulosic composition. Simultaneous wet ball milling and mild acid hydrolysis of rice hull was studied in this work. RESULTS: Ball milling with 150 small stainless steel beads and rotation speed of 600 rpm in citrate solvent of pH 4 was the optimal condition for hydrolysis, and the yield of sugar increased with increased milling time. Corresponding structure transformations before and after milling analyzed by X-ray diffraction (XRD), environmental scanning electron microscopy (ESEM) and transmission fourier transform infrared spectroscopy (FT-IR) clearly indicate that this hydrolysis could be attributed to the crystalline and chemical structure changes of cellulose in rice hull during ball milling in mild acid solvent. CONCLUSION: This combined treatment of ball milling and citrate solvent greatly changed the crystalline and chemical structure and continuously generated sites accessible to citrate solvent, thus enabling hydrolysis of the rice hull. Copyright © 2009 Society of Chemical Industry [source]

Antioxidant Properties of Far Infrared-treated Rice Hull Extract in Irradiated Raw and Cooked Turkey Breast

JOURNAL OF FOOD SCIENCE, Issue 6 2003
S.-C. Lee
ABSTRACT: The antioxidant effect of far infrared-treated rice hull (FRH) extracts in irradiated turkey breast meat was compared with that of sesamol and rosemary oleoresin. The FRH extracts significantly decreased thiobarbituric acid-reactive substances values and volatile aldehydes (hexanal, pentanal, and propanal) and was effective in reducing the production of dimethyl disulfide responsible for irradiation off-odor in irradiated raw and cooked turkey meat during aerobic storage. The antioxidant activity of FRH extracts (0.1%, wt/wt) was as effective as that of rosemary oleoresin (0.1%). However, the addition of FRH extracts increased red and yellow color intensities and produced an off-odor characteristic to rice hull in raw and cooked meat. [source]

Allelochemical tricin in rice hull and its aurone isomer against rice seedling rot disease

PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 9 2010
Chui-Hua Kong
Abstract BACKGROUND: One promising area of rice disease management is the potential of exploiting biological control agents. Rice seedling rot disease caused by soil-borne pathogenic fungi has become a dominant disease problem because of greater use of direct seeding. Rice hull has been potentially used to control paddy weeds, but little information is available on rice disease. This study was conducted to investigate the relationships between disease incidence and soil amended with tricin-releasing rice hull, and to assess fungicidal activity of tricin and its synthesised aurone isomer, with an attempt to develop an allelochemical-based fungicide against rice seedling rot disease. RESULTS: Tricin was detected in all hulls of 12 rice cultivars tested, but its contents in rice hulls varied greatly with the cultivar and genotype. Tricin in rice hulls was released into the soil once amended. Disease incidence was significantly reduced by soil amended with rice hull. Tricin-rich rice hull amendment greatly suppressed soil-borne pathogenic fungi Fusarium oxysporum Schlecht. and Rhizoctonia solani Kühn which cause rice seedling rot disease. In attempting to obtain enough tricin for further experiments, the aurone isomer (5,7,4,-trihydroxy-3,,5,-dimethoxyaurone) of tricin rather than tricin itself was unexpectedly synthesised. This aurone isomer had much stronger fungicidal activity on both F. oxysporum and R. solani than tricin itself. CONCLUSION: Soil amended with tricin-rich rice hull was associated with reduced risk of developing seedling rot disease. The tricin isomer, aurone, is more effective against rice seedling rot disease than tricin itself, making it an ideal lead compound for new fungicide discovery. Copyright © 2010 Society of Chemical Industry [source]

Effect of temperature on hygroscopic thickness swelling rate of composites from lignocellolusic fillers and HDPE

POLYMER COMPOSITES, Issue 11 2009
Abdollah Najafi
Effect of temperature on hygroscopic thickness swelling rate of lignocellolusic fillers/HDPE (high density polyethylene) composites was investigated. The composites were manufactured using a dry blend/hot press method. In this method, powder of plastic and dried powder of lignocellolusic material were mixed in high-speed mixer and then the mixed powder were pressed at 190°C. Lignocellolusic fillers/HDPE composites panels were made from virgin and recycled HDPE (as plastic) and wood sawdust and flour of rice hull (as filler) at 60% by weight filler loadings. Nominal density and dimensions of the panels were 1 g/cm3 and 35 × 35 × 1 cm3, respectively. Thickness swelling rate of manufactured wood plastic composites (WPCs) were evaluated by immersing them in water at 20, 40, and 60°C for reaching a certain value where no more thickness was swelled. A swelling model developed by Shi and Gardner [Compos. A, 37, 1276 (2006)] was used to study the thickness swelling process of WPCs, from which the parameter, swelling rate parameter, can be used to quantify the swelling rate. The results indicated that temperature has a significant effect on the swelling rate. The swelling rate increased as the temperature increased. The swelling model provided a good predictor of the hygroscopic swelling process of WPCs immersed in water at various temperatures. From the activation energy values calculated from the Arrhenius plots, the temperature had less effect on the thickness swelling rate for the composites including wood sawdust compared with the rice hull as filler and the composites including recycled compared with the virgin HDPE as plastic. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers [source]

Oil Spill Cleanup from Sea Water by Sorbent Materials

CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 12 2005
A. Bayat
Abstract Three sorbents were compared in order to determine their potential for oil spill cleanup. Polypropylene nonwoven web, rice hull, and bagasse with two different particle sizes were evaluated in terms of oil sorption capacities and oil recovery efficiencies. Polypropylene can sorb almost 7 to 9 times its weight from different oils. Bagasse, 18 to 45 mesh size, follows polypropylene as the second sorbent in oil spill cleanup. Bagasse, 14 to 18 mesh size, and rice hull have comparable oil sorption capacities, which are lower than those of the two former sorbents. It was found that oil viscosity plays an important role in oil sorption by sorbents. All adsorbents used in this work could remove the oil from the surface of the water preferentially. [source]

Degradation of the main components of cellulose-paint thinner by the mould Scopulariopsis brevicaulis cultured on rice hulls

LETTERS IN APPLIED MICROBIOLOGY, Issue 1 2003
J. Alba
Abstract Aims: Biodegradation of the main components of the cellulose-paint thinner (toluene, acetone, isopropanol and xylenes) by Scopulariopsis brevicaulis, isolated from a thinner biodegradation microbial consortium was investigated. Methods and Results: Our results showed that 90% of S. brevicaulis conidia survived after 4 weeks in a cellulose-paint thinner saturated atmosphere. The mould was able to grow under these environmental conditions with a low development of conidia. The biodegradation potential of S. brevicaulis was established with and without support material (rice hulls). Biodegradation without support was very limited, <10% for all the components quantified. There was notable thinner biodegradation when the fungus was grown on rice hulls. Conclusions: Our results suggest the potential use of fungi in biofiltration systems employed in biodegradation of the main components of the cellulose-paint thinner. Sigificance and Impact of the Study: This is the first report of volatile organic compounds biodegradation by this fungal species. [source]

Allelochemical tricin in rice hull and its aurone isomer against rice seedling rot disease

PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 9 2010
Chui-Hua Kong
Abstract BACKGROUND: One promising area of rice disease management is the potential of exploiting biological control agents. Rice seedling rot disease caused by soil-borne pathogenic fungi has become a dominant disease problem because of greater use of direct seeding. Rice hull has been potentially used to control paddy weeds, but little information is available on rice disease. This study was conducted to investigate the relationships between disease incidence and soil amended with tricin-releasing rice hull, and to assess fungicidal activity of tricin and its synthesised aurone isomer, with an attempt to develop an allelochemical-based fungicide against rice seedling rot disease. RESULTS: Tricin was detected in all hulls of 12 rice cultivars tested, but its contents in rice hulls varied greatly with the cultivar and genotype. Tricin in rice hulls was released into the soil once amended. Disease incidence was significantly reduced by soil amended with rice hull. Tricin-rich rice hull amendment greatly suppressed soil-borne pathogenic fungi Fusarium oxysporum Schlecht. and Rhizoctonia solani Kühn which cause rice seedling rot disease. In attempting to obtain enough tricin for further experiments, the aurone isomer (5,7,4,-trihydroxy-3,,5,-dimethoxyaurone) of tricin rather than tricin itself was unexpectedly synthesised. This aurone isomer had much stronger fungicidal activity on both F. oxysporum and R. solani than tricin itself. CONCLUSION: Soil amended with tricin-rich rice hull was associated with reduced risk of developing seedling rot disease. The tricin isomer, aurone, is more effective against rice seedling rot disease than tricin itself, making it an ideal lead compound for new fungicide discovery. Copyright © 2010 Society of Chemical Industry [source]