• Asian-Australasian Journal of Animal Sciences
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• v.11 no.5
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• pp.503-509
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• 1998

Whole faba beans (WFB) were dry roasted at different temperatures of 110, 130 and $150^{\circ}C$ for 15, 30 and 45 minutes (min) to determine the optimal heating conditions to increase bypass starch as glucose source which may be a limiting nutrient in high producing dairy cattle. Ruminant degradation characteristics of starch (St) of WFB were determined using in sacco method in 6 dairy cows fed 60% hay and 40% concentrate. Measured characteristics of St were soluble (washable) fraction (S), potentially degradation fraction (D) and the rate of degradation (Kd) of the insoluble but degradable St fraction. Based on measurement of these characteristics, percentage bypass starch (%BSt) and bypass starch (BSt) were calculated. Degradability of starch in the rumen was reduced by dry roasting at temperature of 130 and $150^{\circ}C$ and increased at $110^{\circ}C$. S varied from 50.0% in the raw whole faba beans (RWFB) and 53.7% in $110^{\circ}C$/15 min to 18.2% in $150^{\circ}C$/45 min. D varied from 49.9% in RWFB and 46.3% in $110^{\circ}C$/15 min to 81.8 % in $150^{\circ}C$/45 min. Kd varied from 9.8% in RWFB and 11.0% in the $110^{\circ}C$/30 min to 4.2 in $150^{\circ}C$/45 min. All these effects resulted in increasing %BSt from 22.1% in the $110^{\circ}C$/45 min and 23.9% in RWFB to 49.9% in the $150^{\circ}C$/45 min. Therefore BSt increased from 91.4 g/kg and 98.4 g/kg to 199.9 g/kg respectively. Dry roasting at $110^{\circ}C$ increased the starch rumen degradation. Treatment at higher temperature (130 and $150^{\circ}C$) decreased rumen degradation of starch and seemed to be linear up to highest values tested. No optimal dry roasting conditions of treatment could be determined at this stage. It may be concluded that dry roasting at temperatures of 130 and $150^{\circ}C$ was effective in shifting starch degradation from rumen to intestine to increase bypass starch.

• Journal of Soil and Groundwater Environment
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• v.19 no.3
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• pp.82-93
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• 2014

A starch ball was devised to conveniently supply carbon source to indigenous microorganisms and to enhance biotransformation of explosive compounds(TNT and RDX) in the sediments of settling basins installed in military shooting ranges. To identify optimum dose/sediment ratio for degradation of explosives in the basin, a series of bench scale settling basin experiments were performed for 30 days while monitoring supernatant pH, DO, concentrations of nitrite, nitrate, sulfate, explosive compounds, and acute toxicity measured by bacterial luminescence. Addition of starch ball induced changes in oxidation conditions from oxic to anoxic in the benthic zone of the basin, which resulted in subsequent reductive degradation of both TNT and RDX in the liquid and solid phase of basin. However, fermentation products of excess starch, acetic acid and formic acid, caused acute toxicity in the liquid phase. The optimum ratio of starch ball/sediment for explosive compounds degradation by inducing changes in bio-geochemical environments without increase in acute toxicity, was found to be 0.009~0.017.

• Journal of Microbiology and Biotechnology
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• v.30 no.6
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• pp.839-847
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• 2020

In the present study, an anaerobic microbial consortium for the degradation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was selectively enriched with the co-addition of RDX and starch under nitrogen-deficient conditions. Microbial growth and anaerobic RDX biodegradation were effectively enhanced by the co-addition of RDX and starch, which resulted in increased RDX biotransformation to nitroso derivatives at a greater specific degradation rate than those for previously reported anaerobic RDX-degrading bacteria (isolates). The accumulation of the most toxic RDX degradation intermediate (MNX [hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine]) was significantly reduced by starch addition, suggesting improved RDX detoxification by the co-addition of RDX and starch. The subsequent MiSeq sequencing that targeted the bacterial 16S rRNA gene revealed that the Sporolactobacillus, Clostridium, and Paenibacillus populations were involved in the enhanced anaerobic RDX degradation. These results suggest that these three bacterial populations are important for anaerobic RDX degradation and detoxification. The findings from this work imply that the Sporolactobacillus, Clostridium, and Paenibacillus dominant microbial consortium may be valuable for the development of bioremediation resources for RDX-contaminated environments.

• Journal of Soil and Groundwater Environment
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• v.19 no.3
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• pp.56-65
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• 2014

Contamination of explosive compounds in the soils of military shooting range may pose risks to human and ecosystems. As shooting ranges are located at remote places, active remediation processes with hardwares and equipments are less practical to implement than natural solutions such as bioremediaton. In this study, a series of experiments was conducted to select a suitable carbon source and to optimize dosing rate for the enhanced bioremediation of explosive compounds in surface soils and sediments of shooting ranges with indigenous microorganisms activated by external carbon source. Treatability study using slurry phase reactors showed that the presence of indigenous microbial community capable of explosive compounds degradation in the shooting range soils, and starch was a more effective carbon source than glucose and acetic acid in the removal of TNT. However, at higher starch/soil ratio, i.e., 2.0, the acute toxicity of the liquid phase increased possibly due to transformation products of TNT. RDX degradation by indigenous microorganisms was also stimulated by the addition of starch but the acute toxicity of the liquid phase decreased with the increase of starch/soil ratio. Taken together, the optimum range of starch/soil ratio for the degradation of explosive compounds without significant increase in acute toxicity was found to be 0.2 of starch/soil.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.2
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• pp.171-180
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• 2017

Objective: This study investigated the association of enzyme-producing microbes and their enzymes with starch and hemicellulose degradation during fermentation of total mixed ration (TMR) silage. Methods: The TMRs were prepared with soybean curd residue, alfalfa hay (ATMR) or Leymus chinensis hay (LTMR), corn meal, soybean meal, vitamin-mineral supplements, and salt at a ratio of 25:40:30:4:0.5:0.5 on a dry matter basis. Laboratory-scale bag silos were randomly opened after 1, 3, 7, 14, 28, and 56 days of ensiling and subjected to analyses of fermentation quality, carbohydrates loss, microbial amylase and hemicellulase activities, succession of dominant amylolytic or hemicellulolytic microbes, and their microbial and enzymatic properties. Results: Both ATMR and LTMR silages were well preserved, with low pH and high lactic acid concentrations. In addition to the substantial loss of water soluble carbohydrates, loss of starch and hemicellulose was also observed in both TMR silages with prolonged ensiling. The microbial amylase activity remained detectable throughout the ensiling in both TMR silages, whereas the microbial hemicellulase activity progressively decreased until it was inactive at day 14 post-ensiling in both TMR silages. During the early stage of fermentation, the main amylase-producing microbes were Bacillus amyloliquefaciens (B. amyloliquefaciens), B. cereus, B. licheniformis, and B. subtilis in ATMR silage and B. flexus, B. licheniformis, and Paenibacillus xylanexedens (P. xylanexedens) in LTMR silage, whereas Enterococcus faecium was closely associated with starch hydrolysis at the later stage of fermentation in both TMR silages. B. amyloliquefaciens, B. licheniformis, and B. subtilis and B. licheniformis, B. pumilus, and P. xylanexedens were the main source of microbial hemicellulase during the early stage of fermentation in ATMR and LTMR silages, respectively. Conclusion: The microbial amylase contributes to starch hydrolysis during the ensiling process in both TMR silages, whereas the microbial hemicellulase participates in the hemicellulose degradation only at the early stage of ensiling.

• Journal of Industrial Technology
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• v.39 no.1
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• pp.15-19
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• 2019

This work focused on characterization of the starch degradation activity from extremophile strain Deinococcus geothermalis. Glucoamylase gene from D. geothermalis was cloned and overexpressed by pET-21a vector using E. coli BL21 (DE3). In order to characterize starch degrading activity of recombinant glucoamylase, enzyme was purified using HisPur Ni-NTA column. The recombinant glucoamylase from D. geothermalis exhibited the optimum temperature as $45^{\circ}C$ for starch degradation activity. And highly acido-stable starch degrading activity was shown at pH 2. For further optimization of starch degrading activity with metal ion, various metal ions ($AgCl_2$, $HgCl_2$, $MnSO_4{\cdot}4H_2O$, $CoCl_2{\cdot}6H_2O$, $MgSO_4$, $ZnSO_4{\cdot}7H_2O$, $K_2SO_4$, $FeCl_2{\cdot}4H_2O$, NaCl, or $CuSO_4$) were added for enzyme reaction. As results, it was found that $FeCl_2{\cdot}4H_2O$ or $MnSO_4{\cdot}4H_2O$ addition resulted in 17% and 9% improved starch degrading activity, respectively. The recombinant glucoamylase from D. geothermalis might be used for simultaneous saccharification and fermentation (SSF) process at high acidic conditions.

• Archives of Pharmacal Research
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• v.29 no.12
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• pp.1179-1186
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• 2006

Cross-linked starch microspheres were prepared using different kinds of cross-linking agents. The influence of several parameters on morphology, size, swelling ratio and drug release rate from these microspheres were evaluated. These parameters included cross-linker type, concentration and the duration of cross-linking reaction. Microspheres cross-linked with glutaraldehyde had smooth surface compared with those prepared with epichlorhydrine or formaldehyde. The particle size increased with increasing the cross-linking time and increasing the drug loading. Swelling ratio of the particles was a function of cross-linker type but not the concentration or time of cross-linking. Drug release from starch microspheres was measured in phosphate buffer and also in phosphate buffer containing a-amylase. Results showed that microspheres cross-linked with epichlorhydrine released all their drug content in the first 30 minutes. However, cross-linking of the starch microspheres with glutaraldehyde or formaldehyde decreased drug release rate. SEM and drug release studies showed that cross-linked starch microspheres were susceptible to the enzymatic degradation under the influence of alpha-amylase. Changing the enzyme concentration from 5000 to 10,000 IU/L, increased drug release rate but higher concentration of enzyme (20,000 IU/L) caused no more acceleration.

• Journal of Plant Biology
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• v.31 no.4
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• pp.249-258
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• 1988

Changes in starch content and activities of ADPG- and UDPG-starch synthase and $\alpha$- and, $\beta$-amylase were studied in order to investigate effects of gibberellic aicd and abscisic acid on endogenous starch content during shoot differentiation and protocorm propagation in Cymbidium spp. (Jungfrau) protocorm. Shoot differentiation was promoted during the degradation of endogenous starch and protocorn propagation was promoted during starch accumulation in protocorm. The activities of ADPG- and, UDPG-starch synthase and $\alpha$- and $\beta$-amylase seemed to be related with starch content. Shoot differentiation and protocorm propagation were slightly inhibited in protocorm explants treated with 100$\mu$M gibberellic acid. The explants treated with 10$\mu$M abscisic acid lost the capacity for shoot differentiation and protocorm propagation, and that could not be overcome by 100$\mu$M gibberellic acid added to culture medium. Starch content fluctuated as the control even after 10$\mu$M abscisic acid. None the less, the treatment completely inhibited shoot differentiation and protocorm propagation.

• Applied Biological Chemistry
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• v.29 no.3
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• pp.248-254
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• 1986

The product specificity of Bacillus ${\alpha}-amylase$ on raw rice starch has teen studied by using HPLC and scanning electron microscopy (SEM). Analysis of starch degradation products digested by ${\alpha}-amylase$ showed considerable differences between raw and gelatinized rice. The hydrolysis of raw rice starch resulted in formation of more glucose and maltose than those of gelatinized starch. SEM revealed characteristic enzyme degradation patterns. Hollow curvatures were observed in gelatinized starch, indicating the substrate is hydrolyzed in the interior of the starch chain by Bacillus ${\alpha}-amylase$. In contrast, raw starch were hydrolyzed from the end of the substrate, resulting in pinholes over the surface of the starch granules.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1213-1220
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• 2018

Objective: An experiment was conducted to assess the antioxidant contents and activities of colored rice grains and to evaluate their nutritive characteristics in terms of chemical composition and in situ ruminal degradation. Methods: Ten cultivars of colored rice grains (Oryza sativa L.) collected from several areas of Japan were studied, and control rice without pigment, maize, barley, and wheat grains were used as control grains. Their chemical compositions, pigment, polyphenol contents, total antioxidant capacity (TAC), and degradation characteristics were determined. Results: The starch contents of the colored rice grains were in the range of 73.5% to 79.6%, similar to that of the control rice grain. The black and red rice grains contained anthocyanin (maximum: $5,045.6{\mu}g/g$) and proanthocyanidin (maximum: $3,060.6{\mu}g/g$) at high concentrations as their principal pigments, respectively. There were significantly (p<0.05) positive relationships among the pigment contents, polyphenol content, and TAC values in the colored and control rice grains, indicating that the increase in pigment contents also contributed to the increased polyphenol content and TAC values in the colored rice grains. The dry matter and starch degradation characteristics, as represented by c (fractional degradation rate of slowly degradable fraction) and by the effective degradability, of the colored rice grains and the control rice grain were ranked as follows among commonly used grains: wheat>barley${\geq}rice$>maize. The colored rice grains also included the most-digestible starch, since their potential degradable fraction and actual degradability at 48 h incubation were almost 100%. Conclusion: Colored rice grains have high potential to be used as antioxidant sources in addition to starch sources in ruminants.