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Kinds of Husk Selected AbstractsA NEW METHOD FOR ELLAGIC ACID PRODUCTION FROM POMEGRANATE HUSKJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2008JINGJING LU ABSTRACT Pomegranate (Punica granatum L.) husk, a by-product of the pomegranate juice industry, is an inexpensive and abundant source of ellagic acid. Ellagic acid is widely used as functional food for its physiological functions. It is the breakdown product of ellagitannins. To date, the preparation of ellagic acid from pomegranate husk has not been reported. This article reports a new process for ellagic acid production from pomegranate husk by extraction of tannins followed by acid hydrolysis and purification by extraction and recrystallization. Several tests were conducted to obtain optimum conditions including extraction of tannins by varying solvents, acid concentration and reaction time for acid hydrolysis and the volume of methanol used for purification. Ellagic acid (3.5 g) with 90% purity from 100 g pomegranate husk was obtained. This new method is easy to scale up. All equipment used in this production process is widely used in food processing industry. The cost of production is low. It is suitable for industrial applications. PRACTICAL APPLICATIONS The production of ellagic acid is easier and the yield and purity of ellagic acid produced this way are higher than before. This method can be used not only for experiment in laboratory but also for industrial applications. The material , pomegranate husk , is a by-product of the pomegranate juice industry, so it is very cheap and easy to get. High-purity ellagic acid produced this way is sold to many companies back home and abroad. It is used as food additive and cosmetic material because of its antioxidant activity and whiteningfunction. The toxicity of pomegranate husk is lower than that of gallnut, which has been the main material of ellagic acid production in the past. Reagents are common and inexpensive; some of them are reusable. [source] APPLICATION OF COEFFICIENT OF FRICTION TO THE SEPARATION OF COCOA HUSK,BEANS MIXTUREJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2007O.K. OWOLARAFE ABSTRACT Investigation was carried out on the application of coefficient of friction in the separation of cocoa beans,husk mixture. An inclined plane at angles 20, 25 and 35°rotating at different speeds (215, 250 and 260 rpm) and receiving the mixture at heights 30, 60 and 90 mm, was used for the study. The result indicates that within the range of factors considered, the separation efficiency of the beans from the mixture increases with increase in speed of rotation and height of fall, while it decreases with increase in angle of inclination. Statistical analysis shows that the effects of each of the factors and that of their interaction are significant at 99%. The best separation efficiency (99%) was observed at a speed of 250 rpm, an angle of inclination of 25° and a height fall of 90 mm. PRACTICAL APPLICATIONS Separation of cocoa beans from the husks has been a serious problem in cocoa processing. Handpicking is still being used to separate the mixture of cocoa beans,husk even with the mechanical pod breaker available. This therefore constitutes a tedious operation. An inclined plane mechanism tested for the separation of the mixture in this study can be incorporated into the design of the cocoa pod processor to reduce the drudgery involved in cocoa processing and improve the quality of the product. [source] Packed Bed Column Fermenter and Kinetic Modeling for Upgrading the Nutritional Quality of Coffee Husk in Solid-State FermentationBIOTECHNOLOGY PROGRESS, Issue 6 2001Débora Brand Studies were carried out to evaluate solid-state fermentation (SSF) for the upgradation of the nutritional quality of coffee husk by degrading the caffeine and tannins present in it. SSF was carried out by Aspergillus niger LPBx in a glass column fermenter using factorial design experiments and surface response methodology to optimize bioprocess parameters such as the substrate pH and moisture content and aeration rate. The first factorial design showed that the moisture content of the substrate and aeration rate were significant factors for the degradation of toxic compounds, which was confirmed by the second factorial design too. The kinetic study showed that the degradation of toxic compounds was related to the development of the mold and its respiration and also to the consumption of the reducing sugars present in coffee husk. From the values obtained experimentally for the oxygen uptake rate and CO2 evolved, the system determined a biomass yield (Yx/o) of 3.811 (g of biomass)·(g of consumed O2),1 and a maintenance coefficient (m) of 0.0031 (g of consumed O2)·(g biomass of biomass),1·h,1. The best results on the degradation of caffeine (90%) and tannins (57%) were achieved when SSF was carried out with a 30 mL·min,1 aeration rate using coffee husk having a 55% initial moisture content. The inoculation rate did not affect the metabolization of the toxic compounds by the fungal culture. After SSF, the protein content of the husk was increased to 10.6%, which was more than double that of the unfermented husk (5.2%). [source] Influence of crop residue ration supplementation on the attainment of puberty and postpartum reproductive activities of Red Sokoto goatsJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 1-2 2005B. S. Malau-Aduli Summary The general objective of this study was to come up with an appropriate, affordable and locally available crop residue supplementation package that would enhance reproductive performance in small ruminants. Specifically, 28 Red Sokoto weaner does between 3 and 4 months of age weighing between 2 and 3 kg were used in the first experiment to determine the influence of crop residue supplementation on age and weight at puberty as determined by blood progesterone levels. In the second experiment, another 28 adult does (,2 years old) of the same breed in the same flock with lactation numbers between 1 and 3 were used to determine the length of postpartum acyclic period. In both experiments, a 3 × 2 factorial experimental design comprising three dietary supplements (A, B, C) at two feeding levels (1% and 2% of body weight) fed in addition to a basal diet of Digitaria smutsii hay and natural pasture ad libitum with an unsupplemented negative control group (D) and four goats per treatment was utilized. In ration A, a conventional concentrate supplement consisting of maize, wheat offal, cottonseed cake and bonemeal was utilized; in rations B and C, the supplement consisted of guinea-corn bran, cowpea husk and groundnut haulms; and maize offal, groundnut shells and groundnut haulms respectively. Unsupplemented (ration D) weaner does reached puberty at a later age and had lighter body weights than all the others. Weaner does on ration 2A (concentrate fed at 2% of body weight) attained puberty at the earliest age and heaviest body weight, although the age at puberty was not significantly different from those on rations 1A (concentrate fed at 1% body weight), 1C and 2C. Blood progesterone profiles before and after puberty ranged from 0.05 to 9.0 ng/ml, respectively, and was highest in does fed rations A and C and least in the unsupplemented does. The mean interval between kidding and initiation of ovarian activity was 54.28 ± 17.61 days and the mean interval between kidding and conception was 63.04 ± 25.34 days. Only 25% of the unsupplemented does conceived again during the period under study compared with 100% in rations 1A, 2A, 1C and 2C; 75% in ration 2B and 50% in ration 1B. It was concluded that implementation of supplementary feeding in the dry season improves reproductive performance in the Red Sokoto doe. Furthermore, ration C, a crop residue-based ration, was a suitable dry season supplementation alternative to the expensive conventional concentrate ration for the smallholder goat farmer in the subhumid tropics of Nigeria. [source] Effects of rice husk (RH) particle size, glass fiber (GF) length, RH/GF ratio, and addition of coupling agent on the mechanical and physical properties of polypropylene-RH-GF hybrid compositesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2010H. D. Rozman Abstract Polypropylene (PP) hybrid composites based on rice husk (RH) with different particle size and glass fiber (GF) with different length were prepared. The composites were subjected to mechanical and water immersion tests. From the results obtained, it was found that the mechanical properties of the hybrid composites were strongly dependent on the size of RH particle and length of GF. It could be further enhanced with the presence of coupling agent. In this study, two types of coupling agents, i.e., Epolene E-43 (E-43) and 3-(trimethoxysilyl)-propylmethacrylate (TPM), were employed. In general, E-43 imparted significant improvement in the mechanical properties. From the water immersion results, it was found that the hydrophobicity of the composites was increased with the presence of coupling agent. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Production of ,-amylase under solid-state fermentation utilizing coffee wasteJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 8 2009Pushpa S. Murthy Abstract Coffee industry substrates such as coffee pulp, coffee cherry husk, silver skin, spent coffee and mixtures of these coffee wastes (MC) were evaluated for their efficacy as sole carbon source for the synthesis of ,-amylase in solid-state fermentation (SSF) using a fungal strain of Neurospora crassa CFR 308. For SSF with coffee pulp and with MC, ,-amylase activity of 3908 U g,1 ds (units per gram of dry substrate) and 3870 U g,1 ds, respectively, was observed. Parameters such as moisture (60%), pH (4.6), temperature (28 °C), particle size (1.0 mm), inoculum size (107 spores g,1 ds), and fermentation time (5 days) were optimized for enzyme synthesis, wherein 4981 and 4324 U g,1 U g,1 ds of ,-amylase activity was obtained in SSF with coffee pulp and MC, respectively. The enzyme production was further improved when the substrates were subjected to pre-treatment by steaming. Accordingly, maximum ,-amylase activity of 7084 U g,1 ds and 6342 U g,1 ds was obtained with steam-pretreated coffee pulp and MC, respectively, demonstrating them to be excellent sole carbon sources for synthesis of ,-amylase production. Copyright © 2009 Society of Chemical Industry [source] Optimization and analysis of nickel adsorption on microwave irradiated rice husk using response surface methodology (RSM)JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 2 2009Magesh Ganesa Pillai Abstract BACKGROUND: The removal of heavy metals using adsorption techniques with low cost biosorbents is being extensively investigated. The improved adsorption is essentially due to the pores present in the adsorbent. One way of improving the porosity of the material is by irradiation of the precursor using microwaves. In the present study, the adsorption characteristics of nickel onto microwave-irradiated rice husks were studied and the process variables were optimized through response surface methodology (RSM). RESULT: The adsorption of nickel onto microwave-irradiated rice husk (MIRH) was found to be better than that of the raw rice husk (RRH). The kinetics of the adsorption of Ni(II) from aqueous solution onto MIRH was found to follow a pseudo-second-order model. Thermodynamic parameters such as standard Gibbs free energy (,G°), standard enthalpy (,H°), and standard entropy (,S°) were also evaluated. The thermodynamics of Ni(II) adsorption onto MIRH indicates that it is spontaneous and endothermic in nature. The response surface methodology (RSM) was employed to optimize the design parameters for the present process. CONCLUSION: Microwave-irradiated rice husk was found to be a suitable adsorbent for the removal of nickel(II) ions from aqueous solutions. The adsorption capacity of the rice husk was found to be 1.17 mg g,1. The optimized parameters for the current process were found as follows: adsorbent loading 2.8 g (100 mL),1; Initial adsorbate concentration 6 mg L,1; adsorption time 210 min.; and adsorption temperature 35 °C. Copyright © 2008 Society of Chemical Industry [source] Comparative studies of Oryza sativa L. husk and chitosan as lead adsorbentJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 7 2006Mohamed Mohamed Daud Zulkali Abstract The adsorption capacity of two low-cost adsorbents, Oryza sativa L. husk and chitosan, was studied. Lead solution was used as the adsorbate. The effect of initial lead concentration, pH, temperature, weight of adsorbent, particle size and contact time on lead uptake was investigated. It was found that the isotherm data were well described by the Freundlich isotherm for both adsorbents. The adsorption capacities of rice husk and chitosan were 5.69 and 8.31 mg g,1, respectively. It was shown that chitosan was more effective than rice husk. Copyright © 2005 Society of Chemical Industry [source] Pretreatment of barley husk for bioethanol productionJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 1 2005Beatriz Palmarola-Adrados Abstract This paper reports on the optimization of steam pretreatment of barley husk for high pentose and hexose recovery in the subsequent enzymatic hydrolysis step, as well as high ethanol yield, following simultaneous saccharification and fermentation. The parameters optimized in the steam pretreatment step were residence time (5,15 min), temperature (190,215 °C), and concentration of the acid catalyst (0 or 0.5% H2SO4). A microwave oven was employed for screening of the optimal conditions to obtain the highest sugar yield following combined pretreatment and enzymatic hydrolysis. The final optimization of the pretreatment prior to enzymatic hydrolysis was performed on a larger scale, in a steam pretreatment unit. Simultaneous saccharification and fermentation was carried out following steam pretreatment on 5 and 10% dry matter steam-pretreated slurries. Fermentability tests were performed to determine the effect of by-products (ie furfural and 5-hydroxymethyl furfural) in the bioconversion of glucose to ethanol by baker's yeast. The maximum glucose yield, 88% of the theoretical, was obtained following steam pretreatment with 0.5% H2SO4 at 200 °C for 10 min. Under these conditions, a sugar to ethanol conversion of 81% was attained in simultaneous saccharification and fermentation. Copyright © 2004 Society of Chemical Industry [source] A NEW METHOD FOR ELLAGIC ACID PRODUCTION FROM POMEGRANATE HUSKJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2008JINGJING LU ABSTRACT Pomegranate (Punica granatum L.) husk, a by-product of the pomegranate juice industry, is an inexpensive and abundant source of ellagic acid. Ellagic acid is widely used as functional food for its physiological functions. It is the breakdown product of ellagitannins. To date, the preparation of ellagic acid from pomegranate husk has not been reported. This article reports a new process for ellagic acid production from pomegranate husk by extraction of tannins followed by acid hydrolysis and purification by extraction and recrystallization. Several tests were conducted to obtain optimum conditions including extraction of tannins by varying solvents, acid concentration and reaction time for acid hydrolysis and the volume of methanol used for purification. Ellagic acid (3.5 g) with 90% purity from 100 g pomegranate husk was obtained. This new method is easy to scale up. All equipment used in this production process is widely used in food processing industry. The cost of production is low. It is suitable for industrial applications. PRACTICAL APPLICATIONS The production of ellagic acid is easier and the yield and purity of ellagic acid produced this way are higher than before. This method can be used not only for experiment in laboratory but also for industrial applications. The material , pomegranate husk , is a by-product of the pomegranate juice industry, so it is very cheap and easy to get. High-purity ellagic acid produced this way is sold to many companies back home and abroad. It is used as food additive and cosmetic material because of its antioxidant activity and whiteningfunction. The toxicity of pomegranate husk is lower than that of gallnut, which has been the main material of ellagic acid production in the past. Reagents are common and inexpensive; some of them are reusable. [source] APPLICATION OF COEFFICIENT OF FRICTION TO THE SEPARATION OF COCOA HUSK,BEANS MIXTUREJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2007O.K. OWOLARAFE ABSTRACT Investigation was carried out on the application of coefficient of friction in the separation of cocoa beans,husk mixture. An inclined plane at angles 20, 25 and 35°rotating at different speeds (215, 250 and 260 rpm) and receiving the mixture at heights 30, 60 and 90 mm, was used for the study. The result indicates that within the range of factors considered, the separation efficiency of the beans from the mixture increases with increase in speed of rotation and height of fall, while it decreases with increase in angle of inclination. Statistical analysis shows that the effects of each of the factors and that of their interaction are significant at 99%. The best separation efficiency (99%) was observed at a speed of 250 rpm, an angle of inclination of 25° and a height fall of 90 mm. PRACTICAL APPLICATIONS Separation of cocoa beans from the husks has been a serious problem in cocoa processing. Handpicking is still being used to separate the mixture of cocoa beans,husk even with the mechanical pod breaker available. This therefore constitutes a tedious operation. An inclined plane mechanism tested for the separation of the mixture in this study can be incorporated into the design of the cocoa pod processor to reduce the drudgery involved in cocoa processing and improve the quality of the product. [source] Effects of areca nut extracts on the functions of human neutrophils in vitroJOURNAL OF PERIODONTAL RESEARCH, Issue 4 2000Shan-Ling Hung Aqueous extracts of ripe areca nut without husk (ripe ANE) and fresh and tender areca nut with husk (tender ANE) were examined for their effects on the defensive functions of human neutrophils. Exposure of peripheral blood neutrophils to ripe ANE and tender ANE inhibited their bactericidal activity against oral pathogens, including Actinobacillus actinomycetemcomitans and Streptococcus mutans, in a dose-dependent manner. At the concentrations tested, ripe and tender ANEs did not significantly affect the viability of neutrophils as verified by their ability to exclude trypan blue dye. However, both ANEs inhibited the production of bactericidal superoxide anion by neutrophils as measured by cytochrome c reduction. Moreover, the ripe ANE inhibited neutrophils more effectively than did tender ANE. Arecoline, a major alkaloid of areca nut, only exhibited an inhibitory effect on the functions of neutrophils when high concentrations were used. Therefore, arecoline could not be used to explain the inhibitory effects observed for ANEs. In conclusion, our results demonstrated that ripe and tender ANEs reduced the antibacterial activity and the superoxide anion production of neutrophils. This effect may contribute to a less efficient elimination of bacteria from the periodontal environment. Inhibition of the antimicrobial functions of neutrophils may alter the microbial ecology of the oral cavity, and this may be one possible mechanism by which areca nut compromises the oral health of users of areca nut products. [source] Arsenic accumulation by rice grown in soil treated with roxarsoneJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2009Chen-Wuing Liu Abstract Poultry litter is widely used as a fertilizer for lowland rice in Taiwan and China. However, the organic-arsenic compound roxarsone (additive of poultry feed) in poultry litter can be absorbed by the plants and the resulting arsenic (As) contamination may pose a serious threat to human health. This study used various amounts of poultry litter contaminated with roxarsone in pot experiments to evaluate the effect of roxarsone on rice agronomic parameters and the bioaccumulation of total and inorganic As in rice-plant tissues. Rice-grain yield decreased significantly with increasing As content of the soil, and the critical threshold that killed rice was 200 mg roxarsone (kg soil),1. The As concentrations in root, straw, leaf, husk, and grain increased with increasing soil As (p < 1%). At 100 mg roxarsone per,kg of soil, the As concentration in the rice grain exceeded the statutory permissible limit of 1.0 mg As (kg dry weight),1 and at 25 mg roxarsone (kg soil),1, the inorganic As concentrations in grains exceeded the statutory limit of 0.15 mg of inorganic As,kg,1 in China. For all treatments, the As concentrations in various plant tissues at maturity follow the order: root > stem > leaf > husk > grain. Arsenite was the predominant species in root, straw, and grain, while arsenate was the predominant species in leaf and husk. No significant difference existed between the amounts of arsenite and arsenate when various amounts of poultry litter were applied. This result illustrates that large amounts of added roxarsone are not only toxic to rice but also accumulate in grains in the inorganic As forms, potentially posing a threat to human health via the food chain. [source] Cultivation of medicinal isabgol (Plantago ovata) in alkali soils in semiarid regions of Northern IndiaLAND DEGRADATION AND DEVELOPMENT, Issue 3 2006J. C. Dagar Abstract There is growing global demand for medicinal drugs including isabgol (Plantago ovata). With increasing demand of food for an ever-increasing population in India, it is not possible to bring arable lands under cultivation for aromatic and medicinal plants. Salt-affected lands (both saline and alkali) occupy about 8·6 million ha. Due to poor physical properties and excessive exchangeable Na+, most of these lands do not support good vegetation cover. The marginal and salt-affected lands could be successfully utilized for the cultivation of aromatic and medicinal plants. We achieved almost complete germination of isabgol seeds using up to 5000,ppm salt-solution. Grain yield (including husk) was 1·47 to 1·58,t,ha,1 at pH 9·2 showing no significant yield reduction as compared to normal soil. At pH 9·6 the grain yield was 1·03 to 1·12,t,ha,1. At higher pH there was significant reduction in yield. Sowing in good moisture (at field capacity) of soil was found best, but to save time sowing at shallow depth in dry soil, followed by irrigation was also suitable as compared to broadcasting seeds. The chlorophyll content was greater 70 days after sowing compared to younger stages (50 days after sowing). The total chlorophyll and plant biomass were lower from crops grown by broadcasting methods of sowing as compared to two other methods of sowing. The leaf area index (LAI) was higher for the broadcasting method of sowing as compared to the other two methods. Na+ absorption increased and K+ and K+/Na+ ratio decreased with increase in pH. Results reported in this paper clearly indicate that isabgol can successfully be grown on moderately alkali soils up to pH 9·6 without the application of any amendment. Copyright © 2006 John Wiley & Sons, Ltd. [source] First discovery of fossil dung beetle brood balls and nests in the Chadian Pliocene Australopithecine levelsLETHAIA, Issue 4 2000Philippe Duringer The Pliocene continental formations of the paleo-lake Chad system are known because of the recent discovery of the first australopithecine known west of the Rift Valley. The structures under study are found in sandstone levels associated with a rich fauna, including mammals, birds, reptiles and fishes. Analysis of the depositional environment and fauna indicates a mosaic landscape of gallery forest, savannah, grassland and ephemeral rivers interrupted by lacustrine episodes. This sandstone facies contains bioturbation in the form of sandstone balls 4,12 cm in diameter, slightly flattened at the poles. These structures are characterized by an external husk or crust and by a decimetric cavity in the upper part of the ball. Between the husk and the cavity are a number of concave laminae similar to those of a bulb, whose concavity is directed toward the upper cavity. The comparison between these structures and the brood balls of modern Scarabaeidae shows great similarity, especially in the external husk, the concave internal laminae and the chamber of the grub in the upper part of the structures. This bioturbation is interpreted as fossil brood balls of dung beetles (Coleoptera, Scarabaeidae). Fossil dung beetle brood balls are generally rare, but have been known since the 1940s. They can be very abundant in any series, as described by several authors in South America. The first fossil dung balls were described in this area in 1938 by Frenguelli and by Roselli. These authors describe elementary spherical forms of 35 mm in diameter on average, flattened at the poles and with an upper cavity. The fossil dung beetle brood balls discovered in Chad are the first in which all the internal characteristic structures are preserved. Many of them are connected by a remarkably large net of tunnels which has no parallel in the past or the present. [source] Speciation and distribution of arsenic and localization of nutrients in rice grainsNEW PHYTOLOGIST, Issue 1 2009E. Lombi Summary ,,Arsenic (As) contamination of rice grains and the generally low concentration of micronutrients in rice have been recognized as a major concern for human health. Here, we investigated the speciation and localization of As and the distribution of (micro)nutrients in rice grains because these are key factors controlling bioavailability of nutrients and contaminants. ,,Bulk total and speciation analyses using high-pressure liquid chromatography (HPLC),inductively coupled plasma mass spectrometry (ICP-MS) and X-ray absorption near-edge spectroscopy (XANES) was complemented by spatially resolved microspectroscopic techniques (µ-XANES, µ-X-ray fluorescence (µ-XRF) and particle induced X-ray emission (PIXE)) to investigate both speciation and distribution of As and localization of nutrients in situ. ,,The distribution of As and micronutrients varied between the various parts of the grains (husk, bran and endosperm) and was characterized by element-specific distribution patterns. The speciation of As in bran and endosperm was dominated by As(III),thiol complexes. ,,The results indicate that the translocation from the maternal to filial tissues may be a bottleneck for As accumulation in the grain. Strong similarities between the distribution of iron (Fe), manganese (Mn) and phosphorus (P) and between zinc (Zn) and sulphur (S) may be indicative of complexation mechanisms in rice grains. [source] Prevalence and correlates of epileptic seizure in substance-abusing subjectsPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 4 2009Surendra K. Mattoo md Life-time prevalence of epileptic seizures was assessed in 626 consecutive patients treated for substance abuse. Seizures were reported in 8.63% (9.2% in alcohol abusers, 12.5% in opioid abusers). A total of 64.8% of the seizures were associated with substance use. These occurred during withdrawal in the alcohol cohort and during intoxication with dextropropoxyphene and withdrawal from heroin or poppy husk in the opioid cohort. Results indicate that seizures may be more common in older patients with longer duration of dependence among those abusing alcohol. [source] Effects of active silicon uptake by rice on 29Si fractionation in various plant parts,RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 16 2009Jan Reent Köster Rice (Oryza sativa L.) accumulates large amounts of silicon which improves its growth and health due to enhanced resistance to biotic and abiotic stresses. Silicon uptake and loading to xylem in rice are predominantly active processes performed by transporters encoded by the recently identified genes Lsi1 (Si influx transporter gene) and Lsi2 (Si efflux transporter gene). Silicon deposition in rice during translocation to upper plant tissues is known to discriminate against the heavier isotopes 29Si and 30Si, resulting in isotope fractionation within the plant. We analyzed straw and husk samples of rice mutants defective in Lsi1, Lsi2 or both for silicon content and ,29Si using isotope ratio mass spectrometry (IRMS) and compared these results with those for the corresponding wild-type varieties (WT). The silicon content was higher in husk than in straw. All the mutant rice lines showed clearly lower silicon content than the WT lines (4,23% Si of WT). The ,29Si was lower in straw and husk for the uptake defective mutant (lsi1) than for WT, albeit ,29Si was 0.3, higher in husk than in straw in both lines. The effect of defective efflux (lsi2) differed for straw and husk with higher ,29Si in straw, but lower ,29Si in husk while WT showed similar ,29Si in both fractions. These initial results show the potential of Si isotopes to enlighten the influence of active uptake on translocation and deposition processes in the plant. Copyright © 2009 John Wiley & Sons, Ltd. [source] Fluidization characteristics of rice husk in a bubbling fluidized bedTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 2 2010M. A. Leon No abstract is available for this article. [source] An investigation of the relationship between hullability and morphological features in grains of four oat varietiesANNALS OF APPLIED BIOLOGY, Issue 2 2010E. White Milling of oats involves separation of the kernel from its enclosing husk. The ease with which this happens is termed ,hullability'. The association between morphological characteristics measured using image analysis and hullability was examined in oat varieties sampled from Recommended List variety trials conducted at AFBI Crossnacreevy, Belfast, UK in 2000 and 2006. Grain features of the varieties were distinctive and showed differing relationships with weight, Barra changing only slightly, whilst Mascani showed the maximal changes with increasing grain weight. Hullability was poorer in larger grain, and better in Barra and Mascani than in Gerald and Tardis. Fitting of exponential models for the percentage of hulled grain with dehulling duration identified features associated with different aspects of dehulling behaviour. Greater width of grains of Mascani and Tardis was associated with a more rapid increase in hullability at shorter durations of dehulling. Greater roundness in Barra and Gerald in 2000 was associated with better hullability at very short durations of dehulling relative to other varieties. It is concluded that these features of the grain could be of use in selecting high hullability in breeding programmes. [source] RANDOMIZED, CONTROLLED STUDY COMPARING SITZ-BATH AND NO-SITZ-BATH TREATMENTS IN PATIENTS WITH ACUTE ANAL FISSURESANZ JOURNAL OF SURGERY, Issue 8 2006Pravin J. Gupta Background: To determine the efficacy and safety of sitz baths in the management of acute anal fissures. Methods: Individual patients were randomized to either receive sitz baths or no sitz baths for 4 weeks in addition to oral psyllium husk. Patients were asked to soak their hips and buttocks in a tub containing plain lukewarm water for 10 min, once after defecation in the morning and again at bedtime. Each week, the patients were called to assess pain scores and healing of fissures, whereas the level of satisfaction was recorded at the end of 4 weeks. Main outcome measures were validated pain scores and levels of satisfaction. Results: Fifty-eight subjects were recruited for this study. In all, 52 of them completed the trial (27 in the sitz bath group and 25 in the control group). Although the pain score was lesser in the sitz bath group than in the control group, it failed to reach statistical significance. There were no significant differences in fissure healing between the two groups over the 4-week study period. However, patients in the sitz bath group reported better satisfaction levels than the control group (P < 0.01). Although no serious adverse effects were observed, two patients from sitz bath group developed perianal skin rash. Conclusion: This study suggests that sitz baths improve patient satisfaction in acute anal fissures. However, the healing and overall pain relief was not significant enough to attract attention. It was also found to be associated with adverse effects in few patients. [source] Diurnal feeding pattern and gut content of milkfish Chanos chanos (Forsskål, 1775) cultured semi-intensively during the wet and dry season in brackish ponds in the PhilippinesAQUACULTURE RESEARCH, Issue 1 2008Kai-Jens Kühlmann Abstract To improve feeding management and reduce feed cost in semi-intensive grow-out culture of milkfish (Chanos chanos, Forsskål 1775) in brackish ponds, the relative shares of natural food (NF) and supplemental feed (SF) ingested by the fish were microscopically quantified from their completely dissected digestive tracts sampled during 24-h cycles in wet (June,September) and dry (December,April) seasons. Particles from rice husk, indigestible to milkfish, were used as internal markers to quantify supplemental feed. Significantly (P<0.05) more NF than SF (1.4±0.2 vs. 0.4±0.1 g kg,0.8) and SF than NF (1.4±0.8 vs. 0.6±0.3 g kg,0.8) were found during the first month of the wet and the first 3 months of the dry season respectively. Diurnal feeding patterns on SF were significantly higher at morning hours during the dry compared with the wet season. The feeding pattern of milkfish is likely to be affected by the different weather and pond conditions in both seasons. Developing a season-specific pond fertilization management to enhance NF availability in semi-intensive milkfish culture can help to improve the economical and ecological performance of milkfish culture. [source] Extraction and chromatographic separation of anticarcinogenic fractions from cacao bean huskBIOFACTORS, Issue 3 2005Ki Won Lee Abstract The utilization of cacao bean husk (CBH), a by-product of chocolate manufacture, would be both environmentally and economically beneficial. For this purpose, a process for effectively separating and fractionating CBH fractions having cancer preventive potential was developed in this study. For screening the fractions with potent cancer preventive activity, we examined the effect of extracts and fractions of CBH on the inhibition of gap-junction intercellular communication (GJIC) and the DNA synthesis of cancer cells, both of which are characteristics of the promotion and progression stages in carcinogenesis. The extracts of CBH (especially, the 60% ethanol fraction after extraction with 50% acetone) containing 43 wt.% polyphenol exerted an excellent protective effect on H2O2 -induced inhibition of GJIC in WB-F344 rat liver epithelial cells as determined by the scrape-loading/dye transfer assay. The enhancement of GJIC by the extracts of CBH was approximately 10-fold higher than that of a well-known dietary chemopreventive component, vitamin C. The extracts of CBH (especially, the 60% ethanol fraction) also suppressed DNA synthesis in all liver, stomach, and colon cancer cells as demonstrated by the 3H-thymidine incorporation assay, by approximately four-fold higher than that of vitamin C. These results imply that the polyphenol extracts and fractions of CBH are effective functional materials to be used in either preventing or inhibiting cancer. [source] Packed Bed Column Fermenter and Kinetic Modeling for Upgrading the Nutritional Quality of Coffee Husk in Solid-State FermentationBIOTECHNOLOGY PROGRESS, Issue 6 2001Débora Brand Studies were carried out to evaluate solid-state fermentation (SSF) for the upgradation of the nutritional quality of coffee husk by degrading the caffeine and tannins present in it. SSF was carried out by Aspergillus niger LPBx in a glass column fermenter using factorial design experiments and surface response methodology to optimize bioprocess parameters such as the substrate pH and moisture content and aeration rate. The first factorial design showed that the moisture content of the substrate and aeration rate were significant factors for the degradation of toxic compounds, which was confirmed by the second factorial design too. The kinetic study showed that the degradation of toxic compounds was related to the development of the mold and its respiration and also to the consumption of the reducing sugars present in coffee husk. From the values obtained experimentally for the oxygen uptake rate and CO2 evolved, the system determined a biomass yield (Yx/o) of 3.811 (g of biomass)·(g of consumed O2),1 and a maintenance coefficient (m) of 0.0031 (g of consumed O2)·(g biomass of biomass),1·h,1. The best results on the degradation of caffeine (90%) and tannins (57%) were achieved when SSF was carried out with a 30 mL·min,1 aeration rate using coffee husk having a 55% initial moisture content. The inoculation rate did not affect the metabolization of the toxic compounds by the fungal culture. After SSF, the protein content of the husk was increased to 10.6%, which was more than double that of the unfermented husk (5.2%). [source] Forage collection, substrate preparation, and diet composition in fungus-growing antsECOLOGICAL ENTOMOLOGY, Issue 3 2010HENRIK H. DE FINE LICHT 1. Variation and control of nutritional input is an important selective force in the evolution of mutualistic interactions and may significantly affect coevolutionary modifications in partner species. 2. The attine fungus-growing ants are a tribe of more than 230 described species (12 genera) that use a variety of different substrates to manure the symbiotic fungus they cultivate inside the nest. Common ,wisdom' is that the conspicuous leaf-cutting ants primarily use freshly cut plant material, whereas most of the other attine species use dry and partly degraded plant material such as leaf litter and caterpillar frass, but systematic comparative studies of actual resource acquisition across the attine ants have not been done. 3. Here we review 179 literature records of diet composition across the extant genera of fungus-growing ants. The records confirm the dependence of leaf-cutting ants on fresh vegetation but find that flowers, dry plant debris, seeds (husks), and insect frass are used by all genera, whereas other substrates such as nectar and insect carcasses are only used by some. 4. Diet composition was significantly correlated with ant substrate preparation behaviours before adding forage to the fungus garden, indicating that diet composition and farming practices have co-evolved. Neither diet nor preparation behaviours changed when a clade within the paleoattine genus Apterostigma shifted from rearing leucocoprinous fungi to cultivating pterulaceous fungi, but the evolutionary derived transition to yeast growing in the Cyphomyrmex rimosus group, which relies almost exclusively on nectar and insect frass, was associated with specific changes in diet composition. 5. The co-evolutionary transitions in diet composition across the genera of attine ants indicate that fungus-farming insect societies have the possibility to obtain more optimal fungal crops via artificial selection, analogous to documented practice in human subsistence farming. [source] Competition between domestic dogs and Ethiopian wolf (Canis simensis) in the Bale Mountains National Park, EthiopiaAFRICAN JOURNAL OF ECOLOGY, Issue 2 2010A. Atickem Abstract The potential effects of the domestic dogs (Canis familiaris) on the Endangered Ethiopian wolf (Canis simensis) through exploitative and interference competition were studied in the Web Valley of Bale Mountains national park between November 2001 and February 2003. All dogs were owned in the study area and no feral dogs were reported or observed during the research period. The diet of domestic dogs was dominated by barley husks and human faeces which contributed 45% and 20.7% of the total 382 meals observed during focal watch observations. Analysis of dog faeces provided similar results with barley husks, human faeces and animal carcasses occurring in 86.8%, 21.4% and 19.4% of the 1200 faecal samples analysed. Both focal watch and faecal analyses revealed that rodents contributed only a very small proportion of the diet of dogs accounting for only 4.2% of the focal watch and 2.8% of the faecal analysis of roaming dogs. As Ethiopian wolves fed almost exclusively on rodent year round, no significant exploitative competition between dogs and wolves were assessed. Only small proportion of the domestic dogs roamed in the Ethiopian wolf range and interference competition did not appear to be a serious threat for the Ethiopian wolf. Résumé De novembre 2001 à février 2003, on a étudié les effets potentiels des chiens domestiques (Canis familiaris) sur le loup d'Ethiopie (Canis simensis) qui est en danger, en raison d'une compétition par exploitation alimentaire ou par interférences, dans la Vallée de Web, dans le Parc National des montagnes de Bale. Tous les chiens de l'étude avaient un propriétaire, et nous n'avons ni rapporté ni observé de chien féral pendant cette période. Le régime alimentaire des chiens comprenait principalement de la balle d'orge et des excréments humains qui composaient respectivement 45% et 20,7% du total des 382 repas observés pendant des observations focalisées. L'analyse des excréments de chiens donne des résultats semblables : la balle d'orge, les excréments humains et les carcasses d'animaux sont présents dans 86,8%, 21,4% et 19,4% des 1 200 échantillons fécaux analysés. Et les observations focalisées et les analyses des crottes ont révélé que les rongeurs ne composent qu'une toute petite proportion du régime des chiens, avec 4,2% des observations et 2,8% des analyses fécales des chiens errant en liberté. Comme les loups d'Ethiopie se nourrissent toute l'année presque exclusivement de rongeurs, nous avons estimé qu'il n'y avait aucune compétition par exploitation significative entre les chiens et les loups. Seule une petite proportion de chiens circulent dans l'aire de distribution du loup d'Ethiopie, et la compétition par interférence a semblé ne pas constituer une menace sérieuse pour le loup d'Ethiopie. [source] Optimization and analysis of nickel adsorption on microwave irradiated rice husk using response surface methodology (RSM)JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 2 2009Magesh Ganesa Pillai Abstract BACKGROUND: The removal of heavy metals using adsorption techniques with low cost biosorbents is being extensively investigated. The improved adsorption is essentially due to the pores present in the adsorbent. One way of improving the porosity of the material is by irradiation of the precursor using microwaves. In the present study, the adsorption characteristics of nickel onto microwave-irradiated rice husks were studied and the process variables were optimized through response surface methodology (RSM). RESULT: The adsorption of nickel onto microwave-irradiated rice husk (MIRH) was found to be better than that of the raw rice husk (RRH). The kinetics of the adsorption of Ni(II) from aqueous solution onto MIRH was found to follow a pseudo-second-order model. Thermodynamic parameters such as standard Gibbs free energy (,G°), standard enthalpy (,H°), and standard entropy (,S°) were also evaluated. The thermodynamics of Ni(II) adsorption onto MIRH indicates that it is spontaneous and endothermic in nature. The response surface methodology (RSM) was employed to optimize the design parameters for the present process. CONCLUSION: Microwave-irradiated rice husk was found to be a suitable adsorbent for the removal of nickel(II) ions from aqueous solutions. The adsorption capacity of the rice husk was found to be 1.17 mg g,1. The optimized parameters for the current process were found as follows: adsorbent loading 2.8 g (100 mL),1; Initial adsorbate concentration 6 mg L,1; adsorption time 210 min.; and adsorption temperature 35 °C. Copyright © 2008 Society of Chemical Industry [source] Hydrothermal processing of rice husks: effects of severity on product distributionJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 7 2008Rodolfo Vegas Abstract BACKGROUND: Treatment in aqueous media (hydrothermal or autohydrolysis reactions) is an environmentally friendly technology for fractionating lignocellulosic materials. Rice husks were subjected to hydrothermal processing under a variety of operational conditions to cause the selective breakdown of xylan chains, in order to assess the effects of reaction severity on the distribution of reaction products. RESULTS: The effects of severity (measured by the severity factor, R0) on the concentrations of the major autohydrolysis products (monosaccharides, xylo- and glucooligosaccharides, xylooligosaccharide substituents, acetic acid, acid-soluble lignin and elemental nitrogen) were assessed. The interrelationship between the severity of treatment and molecular weight distribution was established by high-performance size-exclusion chromatography. Selected samples were subjected to refining treatments as ethyl acetate extraction and ion exchange for refining purposes, and the concentrates were assayed by high-performance anion-exchange chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. CONCLUSIONS The protein equivalent of the products present in liquors accounted for 43 to 51% of the protein present in the raw rice husks. The concentrations of glucose (derived from starchy material) and arabinose (split from the xylan backbone) were fairly constant with severity. Even in treatments at low severity, high molecular weight compounds derived from xylan accounted for a limited part of the stoichiometric amount. Operating under harsh conditions, about 50% of the total xylan-derived compounds corresponded to fractions with a degree of polymerization (DP) < 9. After refining, saccharides accounted for more than 90% of the non-volatile components of the sample. The refined products showed a series of xylose oligomers up to about DP 13, and a series of acetylated xylose oligomers up to about DP 15. Copyright © 2008 Society of Chemical Industry [source] APPLICATION OF COEFFICIENT OF FRICTION TO THE SEPARATION OF COCOA HUSK,BEANS MIXTUREJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2007O.K. OWOLARAFE ABSTRACT Investigation was carried out on the application of coefficient of friction in the separation of cocoa beans,husk mixture. An inclined plane at angles 20, 25 and 35°rotating at different speeds (215, 250 and 260 rpm) and receiving the mixture at heights 30, 60 and 90 mm, was used for the study. The result indicates that within the range of factors considered, the separation efficiency of the beans from the mixture increases with increase in speed of rotation and height of fall, while it decreases with increase in angle of inclination. Statistical analysis shows that the effects of each of the factors and that of their interaction are significant at 99%. The best separation efficiency (99%) was observed at a speed of 250 rpm, an angle of inclination of 25° and a height fall of 90 mm. PRACTICAL APPLICATIONS Separation of cocoa beans from the husks has been a serious problem in cocoa processing. Handpicking is still being used to separate the mixture of cocoa beans,husk even with the mechanical pod breaker available. This therefore constitutes a tedious operation. An inclined plane mechanism tested for the separation of the mixture in this study can be incorporated into the design of the cocoa pod processor to reduce the drudgery involved in cocoa processing and improve the quality of the product. [source] QUANTIFYING ADULTERATION IN ROAST COFFEE POWDERS BY DIGITAL IMAGE PROCESSINGJOURNAL OF FOOD QUALITY, Issue 2 2003EDSON E. SANO Pure arabica coffee and mixtures of coffee husks and straw, maize, brown sugar and soybean were produced in our laboratory as investigation materials. Red/Green/Blue (RGB) color composites, magnified twelve times, were generated using a Charge Coupled Device (CCD) camera connected to a stereo microscope and a personal computer with an image processing software package. The percent areas of the contaminants in each image were calculated by the Maximum Likelihood supervised classification technique. Best-fit equations relating weight percentage (g.kg -1) and the percent areas were obtained for each coffee contaminant. To test the method, 247 coffee samples of different amounts and types of adulterants were analyzed in the laboratory. The results showed that the new method developed can analyze precisely and quickly a large number of ground coffee powders. [source] |