• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.3
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• pp.177-184
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• 2005

This study was conducted to study the effect of fiber sources on ruminal pH and buffering capacity and whole digestive tract digestibility with five ruminally fistulated sheep. Evaluated fiber sources were alfalfa hay cube (AHC), corn cob (CC), com silage (CS), cotton seed hull (CSH), peanut hull (PHL), rice straw (RS), and sugarcane bagasse (SCB). Sheep were fed consecutively a diet containing each tested fiber source $(45\%)$ with a corn-based concentrate diets $(55\%)$ during each experimental period. Ruminal pH showed no difference among fiber sources except the significantly lower pH at 8h (p<0.05) with RS (pH; 5.78) than those in other sources. Buffering capacity showed significant differences at 0h (p<0.05) and 2h (p<0.05) after feeding in CS compared to those from SCB and CC, while there was higher in PHL (p<0.01) at 12h post feeding except AHC than CC, CS, SCB, and RS. Dry matter digestibility was significantly higher in CS (p<0.001) than in other sources. Neutral detergent fiber digestibility was higher in CC, CS, CSH, and RS than other fiber sources (p<0.001). These results suggest that ruminal pH and buffering capacity and whole digestive track digestibility were significantly affected by fiber sources in ruminant diet, and, therefore, should be took those effects into account for TMR formulation.

• Microbiology and Biotechnology Letters
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• v.37 no.4
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• pp.383-388
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• 2009

A strain YB914 was isolated from soil as a producer of the extracellular xylanase, which catalyzes the hydrolysis of oat spelt xylan. The strain YB914 was identified as Streptomyces sp. on the basis of its morphological, cultural and biochemical properties. The xylanase of culture filtrate was the most active at $55^{\circ}C$ and pH 5.5, and retained 80% of its maximum activity at the range of pH 4.5~7.0. In order to optimize the culture medium for xylanase production, ingredients of G.S.S medium were replaced by several carbohydrates. The carbohydrates such as oat spelt xylan, corn cob xylan, wheat bran and lactose increased the xylanase productivity of Streptomyces sp. YB914. However, xylanase production was greatly repressed by galactose or arabinose. The maximum xylanase productivity was reached to 48 U/mL in the modified medium containing 1% oat spelt xylan and 1.5% lactose.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.543-550
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• 1992

The production of xylanase and $\beta$-xylosidase was investigated in submerged culture of Aspergillus niger NRC 107. The maximum production occurred when the pH was controlled at 6.0 during the fermentation. Among the various carbon sources investigated, corn-cob xylan (1.5%, w/v) yielded maximal production of the enzymes. The $NaNO_{3}$ was the most favorable nitrogen source for enzyme production and $KH_2P0_4$ concentration at 0.3%(w/v) was found to be optimum. Incorporation of wheat bran to the culture medium improved xylanase production. Addition of L( -) sorbose to the culture medium promoted the secretion of $\beta$-xylosidase. It was possible to increase the production of xylanase (39.43 units/ml) and that of $\beta$-xylosidase (4.2 unitslml) by submerged culturing the A. niger NRC 107 in the modified medium.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.3
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• pp.334-339
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• 1995

Removal of apical ear after silking is a method to increase seed production in corn inbreds. Due to the phenomenon of apical dominance, the subapical ear would develope and produce seeds following the removal of the apical ear. This experiment was conducted to investigate the varietal difference in subapical ear development and seed production. Days to silking of subapical ears were delayed by about 4 days compared to normal apical ears. Cob length and filled ear length of subapical ears across seven inbreds tested were reduced by 21% and 36%, respectively. Those of inbred INV302 decreased less and subapical ear of inbred NC246 were barren, which incicated the varietal defferences. Number of kernel rows, kernels per row, and total kernels per ear also decreased. The mean reduction rates for those characters were 28%, 37%, and 47%, respectively. Weights of ears and kernels were reduced and showed different response among inbred lines. Coefficients of variations for cob and filled ear lengths, number of kernel rows and kernels were greater in subapical ears than in apical ears. Seed production of subapical ears was 40 ~ 80% of apical ears, depending on inbred lines when the apical ear is removed immediately after silking.

• Research in Plant Disease
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• v.29 no.2
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• pp.137-144
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• 2023

Exserohilum turcicum is a fungus that causes northern corn leaf blight (NCLB) and has deleterious effects on maize production globally. Therefore, it is prudent to mitigate the effects of NCLB using genetic diversity. The objective of this research was to assess the severity of NCLB disease on the growth and yield of various maize genotypes. A randomized complete block design field experiment, replicated three times, was conducted to evaluate the effect of E. turcicum on 10 maize hybrids. Percent disease index, plant height, and leaf area were recorded at the silk stage. Cob weight, grain fresh weight, and grain yields were determined at harvest maturity. All measured parameters were significantly different (P<0.05) between the maize hybrids. Of the 10 genotypes, four (PAN 4R-528R, PAN 4R-728BR, PAN 3R-724BR, and P1788BR) were susceptible, five (DKC74-74BR, PAN 5R-582R, PAN 5R-890R, PAN 5R-854R, and PAN 5R-590R) were moderately susceptible, and one (DKC80-40BR) was moderately resistant. DKC80-40BR exhibited greater cob weight, while DKC74-74BR was superior in all other plant growth and yield components. Interestingly, although not significant (P>0.05) and high, maize growth and yield parameters had negative correlations with disease incidence, except for grain fresh weight. Therefore, DKC80-40BR may be selected for cultivation in areas prone to NCLB to reduce maize susceptibility to the disease, while DKC74-74BR may improve crop performance. These hybrids could be considered as potential sources of resistance or tolerance to NCLB for further validation by plant breeders.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.591-597
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• 2023

Pakistan depends heavily on imports for its fuel requirements. In this experiment, catalytic pyrolysis of a blend of feedstock's consisting of date seed, wheat straw, and corn cob was conducted in a fixed bed reactor to produce oil that can be used as an alternative fuel. The main focus was to emphasize the outcome of important variables on the produced oil. The effects of operating conditions on the yield of bio-oil were studied by changing temperature (350-500 ℃), heating rate (10, 15, 20 ℃/min), and particle size (1, 2, 3 mm). Moreover, ZnO was used as a catalyst in the process. First, the thermal degradation of the feedstock was investigated by TGA and DTG analysis at 10 ℃/min of different particle sizes of 1, 2, and 3mm from a temperature range of 0 to 1000 ℃. The optimum temperature was found to be 450 ℃ for maximum degradation, and the oil yield was indicated to be around 37%. It was deduced from the experiment that the maximum production of bio-oil was 32.21% at a temperature of 450 ℃, a particle size of 1mm, and a heating rate of 15 ℃/min. When using the catalyst under the same operating conditions, the bio-oil production increased to 41.05%. The heating value of the produced oil was 22 MJ/kg compared to low-quality biodiesel oil, which could be used as a fuel.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.392-401
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• 2023

Corn (Zea mays L.) is one of the world's most important crops, along with wheat and rice, with a global corn production expected to reach 1,154.5 million tons in 2023. Considering this grain production, The generation of corn cob is expected to reach approximately 207.8 million tons in 2023. However, as an agricultural by-product, corn cobs are often considered waste and remain underutilized. Phytosterols, which are abundant in vegetable oils such as corn oil, provide a number of health benefits, including liver health, cholesterol reduction, and protection against chronic diseases such as diabetes. In this study, we investigated the potential of Kwangpyeongok ears, which are commonly used as grain and silage corn in Korea. We also examined the variation in phytosterol content with the maturity of corn ears to identify the optimal time for utilization. At the beginning of physiological maturity, corn cobs had 113.3 mg/100g DW of total phytosterols, which was highest phytosterol abundance during the growth stage. Corn kernels also had the highest phytosterol content at the beginning of physiological maturity. While previous studies on corn bioactive compounds have mainly focused on the kernels, the results of this study highlight that cobs are an excellent source of these compounds. Furthermore, phytosterol levels were influenced by genetic factors and developmental stages, suggesting the to increase the use of cobs as a source of bioactive compounds.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.1
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• pp.42-47
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• 2006

This study was conducted to investigate the efficacy of surface spraying of antimicrobial solutions, oil and application of both on performance of broiler chicken under heat stress and reared on leaves and ground corn cobs as two alternative bedding materials. Six hundred seventy five day-old straightrun Arian broiler chicks were randomly assigned to 45 pens (at density of $0.09m^2/bird$) in an open sided partially-controlled shed. Three bedding materials viz. wood shavings (WS), ground corn cobs (GCC) (1.5 cm in length) and leaves were subjected to surface spraying of oil ($0.4L/m^2$ animal food grade sunflower oil), anti microbial solutions (3%) and mix treatment of both. Data on performance traits, incidence of breast and food pad lesions and litter characteristics were gathered and analysed in an appropriate factorial arrangements. Body weight at 56 d, feed intake up to 14 d, litter moisture at 28 d, litter pH at 14 d and litter temperature at 14 and 56 d were significantly influenced by litter type (p<0.05). Litter treatment revealed significant impact on body weight at 28, 42 and 56 d, feed intake during 29-42 and 1-42 d, mortality up to 56 d, litter temperature at 28 and 56 d, and litter pH at 28 and 56 d. Leaves and ground corn cobs have shown good potential as alternative bedding materials for rearing broilers. Surface spraying of antimicrobial solutions, oil and applying both were not effective tools to promote the broiler's health and performance. Meat type poultry growers and integrators are considered as primary audiences of the results achieved.

• Microbiology and Biotechnology Letters
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• v.4 no.4
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• pp.145-151
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• 1976

Cultural characteristics of a strain of Streptomyces sp. K-14 (KFCC 35051) producing glucose isomerase were demonstrated. The glucose isomerase was produced when the strain was grown in the medium containing pure xylan or xylan.containing materials such as wheat bran or com cob. The optimum condition was attained in a culture medium composed of 3 % wheat bran or com cob, 2 % com steep liquor, 0.1% $MgSO_4$$7H_2O$ and 0.012 % $CoSO_4$$7H_2O$ for the production of the glucose isomera,e. The production of the enzyme reached to a maximum level when the strain was cultured for 40 hrs $30^{\circ}C$ and pH 7.0.

• Microbiology and Biotechnology Letters
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• v.11 no.3
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• pp.193-199
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• 1983

Systematic bioconversion process for the production of xylose from agricultural wastes such as barley straw and corn cobs was studied. After the pretreatment in 1 % NaOH solution for 24 hours at 3$0^{\circ}C$, enzymatic hydrolysis of barley straw for 48 hours at 3$0^{\circ}C$ resulted in the liberation of 15.8% of reducing sugar which is equivalent to 87% of total D-xylose content. Among various agricultural wastes, corn cob as well as barley straw was demonstrated to be potent sources for the production of D-xylose by the process of enzymatic conversion.