• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.5 s.113
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• pp.50-55
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• 2005

In previous report, we investigated the impact of hexeneuronic acid and some residual extractiveson lignin determination. These non-lignin components severely interfered lignin content determination which also affect on the oxygen delignification comparison between aspen and pine unbleached kraft pulps. Very different pattern was observed whether based on uncorrected conventional kappa number or based on corrected kappa number in oxygen delignification comparison. Lower kappa number aspen pulps showed poor response to oxygen delignification when kappa number was used as lignin determination method but better response with using the acid lignin method. Phenolic hydroxyl group in kraft pulps were also compared based on uncorrected or corrected kappa numberfor lignin content. Based on uncorrected kappa number, lower kappa number oxygen-delignified pulps had lower phenolic hydroxyl group. However, lower kappa number oxygen-delignified pulps showed much higher phenolic hydroxyl group based on the corrected lignin content. For accurate comparison for residual lignin properties from different pulps, lignin determination should be corrected from non-lignin components contribution to lignin.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.5 s.108
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• pp.62-68
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• 2004

The amount of non-lignin components in unbleached and oxygen-delignified kraft pulps and their impact on lignin determinations was investigated. The lignin analyses investigated were kappa number and Klason lignin in conjunction with acid-soluble lignin. The species investigated were loblolly pine, and aspen. The non-lignin components that impacted on lignin determination were residual extractives and hexenuronic acid in unbleached and oxygen-delignified kraft pulps. In the hardwoods, significant amounts of extractives remained after kraft pulping and oxygen delignification. These residual extractives in the hardwood pulps had an impact on the lignin determination, more so on the acid lignin method than kappa number. Hexenuronic acid only impacts on kappa number determination both softwood and hardwood pulps, not on acid lignin. Hexeneuronic acid contributed as lignin content more in aspen than pine pulps, and more in oxygen-delignified than unbleached kraft pulps. Impact of hexenuronic acid on should be corrected both softwood and hardwood pulps for accurate kappa number.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.11
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• pp.1686-1694
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• 2019

Objective: Lignin plays a relevant role in the inhibition of cell wall (CW) structural carbohydrate degradation. Thus, obtaining accurate estimates of the lignin content in tropical plants is important in order to properly characterize the mechanism of lignin action on CW degradation. Comparing conflicting results between the different methods available for commercial use will bring insight on the subject. This way, providing data to better understand the relationship between lignin concentration and implications with tropical forage degradation. Methods: Five grass species, Brachiaria brizantha cv $Marand{\acute{u}}$, Brachiaria brizantha cv $Xara{\acute{e}}s$(MG-5), Panicum maximum cv Mombaça, Pennisetum purpureum cv Cameroon, and Pennisetum purpureum cv Napier, were harvested at five maturity stages. Acid detergent lignin (ADL), Klason lignin (KL), acetyl bromide lignin (ABL), and permanganate lignin (PerL) were measured on all species. Lignin concentration was correlated with in vitro degradability. Results: Highly significant effects for maturity, lignin method and their interaction on lignin content were observed. The ADL, KL and ABL methods had similar negative correlations with degradability. The PerL method failed to reliably estimate the degradability of tropical grasses, possibly due to interference of other substances potentially soluble in the $KMnO_4$ solution. Conclusion: ADL and KL methods use strong acid ($H_2SO_4$) and require determination of ash and N content in the lignin residues, therefore, increasing time and cost of analysis. The ABL method has no need for such corrections and is a fast and a convenient method for determination of total lignin content in plants, thus, it may be a good option for routine laboratory analysis.

• Mycobiology
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• v.35 no.4
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• pp.205-209
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• 2007

Ergosterol involves in fungal cell growth as a major component in fungal cell membranes. It can be an indicator that shows the fungal activity, and its content depends on the fungal strains, culture, growth conditions and so on. In this study, fungal activities and growth patterns of three white-rot fungi strains isolated in Korea were evaluated by determination of ergosterol contents during the incubation. Wood decay test and chemical analyses of wood were also performed to verify the relationship between fungal activity and wood degrading capacity of white-rot fungi for 60 days. In the results of experiments, it is considered that the test strains selectively degrade large amount of lignin in wood at the early stage of decay. Especially, Phanerochaete chrysosporium showed the best capability on selective degradation of lignin among the test fungi. It is suggested that the determination of ergosterol content in the fungal culture during the incubation is the simple and effective screening method of white-rot fungi for the application to biopulping of wood.

• Journal of the Korea Organic Resources Recycling Association
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• v.15 no.4
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• pp.131-137
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• 2007

In this study, the biodegradation test on lignocellulose under sulfate reducing conditions was carried out. In particular, the interaction between cellulose and lignin was investigated with various g-cellulose/g-lignin (C/L) ratios: 42.15, 4.59, 2.51, 1.14 and 0.7. It was shown that the rate of cellulose degradation decreased in proportion to the lignin content. Assuming first order degradation kinetics, the consequences of competitive inhibition were graphically shown for different C/L ratios. The relation between cellulose reduction rate and C/L ratio was expressed by logarithm function with a determination coefficient of 0.97. Lignocellulose reduction rate was also described as a logarithm function of C/L ratio showing a inhibition effect by lignin. In the mean time, the rate of lignin decomposition was higher at C/L ratio of 2.51 and 1.14 compared with C/L ratios of 4.59 and 0.7, indicating that excessive extra carbon source is not appropriate for lignin biodegradation.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.10
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• pp.568-574
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• 2017

The purpose of this study was to optimize experimental conditions (time ($X_1$) (ranging of 26.36 - 93.64 min), concentration of sulfuric acid ($X_2$) (ranging of 0-2.5%) and temperature ($X_3$) (ranging of $136.4-203.6^{\circ}C$) for an organosolv pretreatment process to extract lignin from waste wood. The resulting quadratic model equation using RSM (response surface methodology) represented y (lignin yield) = $-79.89+0.91X_1+9.8X_2-2.54{\times}10^{-3}X_1{^2}-2.11X_2{^2}$. The $R^2$ (coefficient of determination) value of 0.8531 for a model indicates this model has statistically significant predictors at the 10% levels. The predictive results optimized by quadratic model produced a lignin yield of 12.46 g/100 g of dry wood under conditions of $178.2^{\circ}C$ and 2.32% $H_2SO_4$. The lignin yield was more affected by the acid catalyst concentrations than the reaction temperature, but the reaction time was not an influential factor for improving lignin extraction from waste wood in this organosolv pretreatment. According to ANOVA (analysis of variance), the significance probability (p-value) of model was smaller than 0.001 and simulation of obtained model equations showed a good reproducibility based on actual organosolv tests under optimal conditions.

• The Korean Journal of Food And Nutrition
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• v.8 no.1
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• pp.23-31
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• 1995

To provide the basic information of buckwheat insoluble dietary fiber (IDF) and efficient material for the buckwheat processed foodstuffs, buckwheat (Fagopyrum egculentum Moench) was germinated at 1$0^{\circ}C$ for 7 days and the contents and composition of the insoluble dietary fiber were examined at 24 hour intervals. The NDF and ADF contents in ungerminated seeds were 20.27%, 18.95% on dry weight basis, respectively. During the germination period, the NDF and ADF contents increased gradually. The cellulose, hemicellulose and lignin contents in ungerminated seeds were 11.10%, 1.32% and 7.85%, respectively. During the germination period, the cellulose and lignin contents increased. However, there was no significant change in the hemicellulose contents. The composition of cellulose and hemicellulose in the NDF decreased with germination time, whereas that of lignin increased. The IDF contents obtained by Prosky method were higher than the NDF contents obtained by Van Soest method. However, the IDF and NDF contents were closely correlated(r=0.9785, p<0.01). The cellulose(Xl), hemicellulose(X2), lignin(X3) and soluble dietary fiber (SDF) (BL) showed the significant regression equation(p<0.001) with the root length(Y). The multiple regression equation was Y = -12.1306 + 0.9213xl - 0.1615$\times$2 + 0.1071$\times$3 + 0.7397$\times$4 and R2(coefficient of determination) was 0.942.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.3
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• pp.49-54
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• 1987

Procedures for Dietary Fiber(DF) determination were applied to some common vegetables. The samples selected in this study were: Radish(Leaf), Chinese cabbage, Spinach, Shepherd's purse, Red pepper(Leaf), Perilla(Leaf), Soybean(Leaf) and Cabbage. DF was analyzed by the method of detergent fractionation. Values for NDF, ADF, Lignin, Hemicellulose, Cellulose were obtained. NDF for most samples was $12.9{\sim}27.4%$, except Soybean(Leaf) (41.9%), ADP was $7.7{\sim}16.9%$. Lignin was around $1.0{\sim}2.1%$; Red pepper (Leaf) (7.6%), Perillar(Leaf) (5.7%), Soybean(Leaf) (4.2%) were exceptions. $Hemicellulose(NDF{\sim}ADF)$ was about $2.9{\sim}12.0%$, except Soybean(Leaf) (25.0%). $Cellulose(ADF{\sim}Lignin)$ was $6.3{\sim}13.0%$. This paper describes two properties of the fiber of commonly eaten vegetables; Water-Holding Capacity(WHC) and Density. The capacity of the ADP to hold water was estimated. The WHC measurements differed from 6.6g per g of ADP for Red pepper(Leaf) to 10.4g per g of ADP for Radish(Leaf). Radish(Leaf), Soybean(Leaf) had the greatest WHC whereas Red pepper(Leaf), Perillar(Leaf) had the least. Two types of density determinations are shown. Direct (non-packed) values largely correspond with bulk(packed) density.

• Korean Journal of Food Science and Technology
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• v.25 no.4
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• pp.299-306
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• 1993

Determination of dietary fiber contents in some Korean foods was attempted by Englyst's gas chromatographic and colorimetric methods which measure the nonstarch polysaccharide (NSP) contents NSP values, except seaweeds, by gas chromatography (x) and colorimetry (y) were very closely correlated (y=1.01x-0.52, r=0.997, n=9), NSP values by gas chromatography were lower than total dietary fiber (TDF) Haloes by AOAC method. By adding lignin to NSP values, relation between the two methods was improved. But, TDF values (y) by adding lignin to NSP values and TDF values (x) by AOAC method were related as y=0.68x-0.64 and F=0.903(n= 12), which was not closely related.

• Korean journal of food and cookery science
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• v.7 no.3
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• pp.69-76
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• 1991

Recent epidemiological observations suggested beneficial effects of dietary fiber on man's health. The obsective of this study was to obtain the dietary fiber reference data of mushrooms. The dietary fiber contents of six different mushrooms (Cornellus edodes, Auricularia auriculajudae, Gyrophora esculanta, Agaricus bisporus, Pleurotus ostreatus, Collybia velutipes) were analyzed by Southgate method, modified neutral detergent fiber (NDF) method and Food Research Institute (FRI) method. Duplicate sample were used for each determination. The mean values of total dietary fiber by Southgate method, modified NDF method and FRI method were respectively $20.08\pm1.45g$/100g dry weight, $20.24\pm1.85g$/100g dry weight and $21.5\pm2.70g$/100g dry weight. The mean values of all mushroom samples by FRI method were significantly different from the mean values of the samples by modified NDF method and Southgate method. However, there was no difference in the mean values of the samples between modified NDF method and Southgate method. By Southgate method, total dietary fiber of mushrooms composed of 1.7-3.1% soluble fiber, 47.0-66.6% hemicellulose, 28.4-57.7% cellulose and 0.9-3.3% lignin. By modified NDF method, total dietary fiber of mushrooms composed of 61.8-79.1% hemicellulose, 5.4-32.9% cellulose and 4.5- l5.5% lignin. Therefore, dietary fiber contents of mushrooms were mainly hemicellulose. Our values for total dietary fiber for six mushrooms were 2~4 times higher than crude fiber in textbook.