• International Journal of Industrial Entomology and Biomaterials
• /
• v.41 no.2
• /
• pp.36-44
• /
• 2020

Mulberry root bark is one of potential plant sources for antioxidant materials which can be used for the relief of oxidative stress. To explore the effects of solvent type and temperature on the structural characteristics and antioxidant activity of the root bark extracts, we prepared various extracts of mulberry root bark (Morus alba L.) using 0 - 100 % ethanol (EtOH) at RT - 100℃. EtOH concentration and temperature critically affected the extraction yields, the content of bioactive components, and antioxidant activity of the extracts. Use of high content of EtOH solvent and low temperature resulted in the low extraction yield. Meanwhile, it was revealed that the extract prepared using absolute EtOH at room temperature contained polyphenols and flavonoids with the highest contents among other extracts. Interestingly, the temperature differently affected the polyphenol and flavonoid contents according to the solvent types. In the case of 30% EtOH solvent, polyphenol and flavonoid contents increased with an increase in temperature, whereas in the case of 70 and 100 % EtOH, these contents decreased. Using the radical scavenging assay, it was confirmed that the 100% EtOH extracts had higher antioxidant activity compared to distilled water (DW) extracts regardless of temperature. Also, heating might extract more antioxidant components from the root bark. Especially, the extract prepared using 30% EtOH solvent at 100℃ showed the highest antioxidant activity. Taken together, these experimental results imply that the extraction parameters should be designed carefully considering the productivity, the extracted bioactive components, and antioxidant activity.

• Journal of the Korean Wood Science and Technology
• /
• v.34 no.1
• /
• pp.40-51
• /
• 2006

The objective of this research is to analyze a possibility for the utilization of carbonized bark and develop the technique for carbonization of bark for using as the adsorbent, the soil improvement agent, the carrier for microbial activity, health products, and so on. The properties of bark charcoals such as methylenehlue adsorption (MBA), equilibrium moisture content (EMC), far infra rad emissivity, pH, water retention and caloric value were analyzed. The MBA values of bark charcoals carbonized for 8 hr of carbonization time at $800^{\circ}C$ of carbonization temperature for Larix leptolepis, Pinus koraiensis, Pinus rigida were greater than 110 mg/g. The bark charcoals pH values of all three species that were carbonized for 4 hr of carbonization time at $400^{\circ}C$ of carbonization temperature was 6.6 and carbonized for 4 hr at 600 and $800^{\circ}C$ was about 9. Therefore the bark charcoals of those species could be used as charcoals if the carbonization temperature and time were controlled.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.43 no.4
• /
• pp.59-66
• /
• 2011

This study was carried out to develop the automation bark peeling process of paper mulberry for making Hanji. Nowadays, almost raw material has been imported from south-east asia for making Hanji. Raw material dependence is very high for Hanji-making by low productivity in korea. This study is focused on the resolution for problem of bark peeling automation. Water and sand jet of compressed air was possible bark peeling for black bast fiber. The effect of removing black bast fiber increased the longer the steaming time. Also using drum of bark peeling showed that results under temperature $80^{\circ}C$ and Rpm 50/min were best bark peeling and separating bast fiber from stem. The contents of holocellulose, lignin, ethanol-benzene extractives, and ash were 91.63~95.55%, 1.4~2.0%, 1.12~1.65%, and 1.4~4.3%, respectively. Chemical characteristics are similar between imported raw-material with drum bark.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.36 no.12
• /
• pp.1257-1269
• /
• 2012

The dyeing behaviors of berberine chloride, palmatine chloride hydrate, and Phellodendron bark extract on silk fabric were investigated to evaluate palmatine as another chromophoric substance of Phellodendron bark. The dyeing conditions were composed of combinations of pH (3, 5, 7, 9), temperature (10, 30, 55, $80^{\circ}C$), and time (10, 30, 60 min). The results indicate that palmatine was comparable to berberine in the dyeing behaviors tested for this study and the results were statistically significant. The dye exhaustion and dye uptake of palmatine-CH were slightly lower than berberine-C, which however were not statistically significant. Similar to berberine-C, palmatine-CH favored a pH 7 condition for both dye exhaustion and dye uptake. However, palmatine-CH favors a higher dyeing temperature and longer dyeing time than berberine-C for superior dyeing results.

• Journal of the Korean Wood Science and Technology
• /
• v.16 no.3
• /
• pp.17-21
• /
• 1988

In order to investigate the extending effects on urea-formaldehyde resin- or phenol- formal- dehyde resin- glued keruing plywood, hot pressing temperatures were controlled to 110, 140, 170 and $200^{\circ}C$. As the extender, wheat flour, persimmon bark powder, chestnut bark powder, the equivalently- extended with the above three powders, and diatomite powder were respectively mixed with 5, 10, 15 and 20% ratios to the resin liquid, and also with these the no- extended was allowed. Based on the measured bonding strength, the conclusions were drawn: 1. In the urea- formaldehyde resin, extending effects on the bonding strength were in the order of wheat flour, the equivalently- extended with the wheat flour, persimmon- and chestnut bark powder, persimmon bark powder, chestnut bark powder. In the phenol- formaldehyde resin, the effects in the order of wheat flour, persimmon bark powder, diatomite powder, chestnut bark powder were resulted in. Specifically, superior bonding strength to the no-extended were given with the wheat flour and persimmon bark powder. 2. On the whole, the bonding strength decreased gradually, as the hot pressing temperature increased except for the diatomite powder extending.

• Journal of the Korean Wood Science and Technology
• /
• v.17 no.4
• /
• pp.26-34
• /
• 1989

This study was carried out to manufacture bark board from oak bark by new processes and to examine the physical and mechanical properties of the board. This process with no addition of adhesive used higher pressure and temperature than the conventional one and was applied with or without paraformaldehyde. The results are as follows: 1. The new manufacturing process allowed a good bark board with high absorption coefficient. 2. The best manufacturing process for the mechanical properties of bark board was paraformaldehyde 10%-$250^{\circ}C$-100kg/$cm^2$-3 minutes, (bending strength 40kg/$cm^2$, internal bonding strength 2kg/$cm^2$) and the best manufacturing process for both the mechanical properties of bark board and economic point of view was $250^{\circ}C$-100kg/$cm^2$-3 minutes (bending strength 28kg/$cm^2$, internal bonding strength 1.52kg/$cm^2$). 3. Bark board showed specific gravities from 0.94 to 1.03 and air dried moisture content 9.2% to 11.7%, but Bark board needed paraffin wax emusion treatment. 4. The absorption coefficient of bark boards had two peaks along with frequency; one in 200-400 cps, the other 1200-2000 cps. The former was low but the latter great.

• Korean Journal of Environmental Agriculture
• /
• v.23 no.4
• /
• pp.240-244
• /
• 2004

The objective of this research was to develop the adsorbent far heavy metals by activating the bark sample. Barks from pine tree with diameters of $2{\sim}4\;mm$ were activated in the muffle furnace under a high relative humidity condition at temperatures of $600{\sim}900^{\circ}C$. The removal efficiency of the activated bark (ACTBARK) for Cu and Cd was temperature dependent showing the order of $900^{\circ}C$ > $800^{\circ}C$ > $700^{\circ}C$ > $600^{\circ}C$. The critical temperature was considered to be $900^{\circ}C$ to become an efficient adsorbent for Cu and Cd. The bark samples activated at temperatures lower than $700^{\circ}C$ showed a less removal efficiency than the crude bark. The ACTBARK activated at $900^{\circ}C$ removed more Cu and Cd from solution than the commercial activated carbon and charcoal. The ACTBARK (activated at $900^{\circ}C$) adsorbed all of the Cu and Cd in solution with concentrations less than 150 mg/L. The selectivity of the ACTBARK was in the order of Cu > Zn > Ni > Pb > Fe > Cd > Mn.

• Journal of the Korean Wood Science and Technology
• /
• v.24 no.4
• /
• pp.1-6
• /
• 1996

Extracts from bark have been studied with a view to producing water-proof wood adhesives. Lately many softwoods, such as radiata pine from New Zealand and larch from Siberia, Russia, have been imported and utilized, and their residual barks would be expecting as potential raw materials for something useful chemicals. The great effort toward utilization of bark extractives as a chemical feedstock has been made on a worldwide level. However few report has been done for the utilization of tree bark extractives in Korea. Hot-water extracts were prepared from barks of Japanese larch(Larix leptolepis). Siberian larch(Larix gmelinii) and Radiata pine(Pinus radiata). The effect of various factors, such as particle size, liquor ratio, extraction temperature, and reaction time, on the extractive yields was discussed. Particle sizes affected the hot-water extractives: the finer the particle size, the higher extractives and extract efficiency. Higher temperature and higher liquor ratio were more effective. Extractives from Japanese larch were relatively less than those from Siberian larch and Radiata pine barks. Formaldehyde precipitates was the highest in extractives of Radiata pine barks. It could be concluded that Siberian larch bark was the best raw material for tannin adhesives, because its extractive yield was higher than those of the other barks.

• Journal of the Korean Wood Science and Technology
• /
• v.35 no.4
• /
• pp.29-37
• /
• 2007

To evaluate the effect of carbonization temperature of charcoal on the heavy metal adsorption property, Quercus mongolica wood and Larix kaempferi bark powder (100~60 mesh) were carbonized at between 400 and $900^{\circ}C$ at intervals of $100^{\circ}C$. In the properties of carbonized materials which affect the adsorption ability, pH increased with increasing the carbonization temperature, so that the pHs of wood and bark charcoal carbonized at $900^{\circ}C$ were 10.8 and 10.4, respectively. Also, in both materials, the carbon content ratio became larger as the carbonization temperature was raised. At the same carbonization temperature, carbon content ratio of the bark charcoal tended to be greater than that of the wood charcoal. In case of iodine adsorption which indicates the adsorption property in liquid phase, the wood charcoal showed higher adsorption value than the bark charcoal. From the investigation of adsorptive elimination properties of the charcoals against 15 ppm Cd, Zn, and Cu, the higher the carbonization temperature, the greater elimination ratio was. In comparison, the wood charcoal presented higher elimination ratio than that of the bark charcoal. In the wood charcoals carbonized at higher than $500^{\circ}C$, especially, 0.2 g of the charcoal was enough to eliminated almost 100% of the heavy metal ions. Heavy metal ion elimination ratio of the charcoals depended on the kinds of adsorbates. The effectiveness of adsorbates in adsorptive elimination by the charcoals were in order of Cu > Cd > Zn. This is because the physicochemical interaction between the adsorbate and adsorbent affects their adsorption properties, it is considered that subsequent researches are needed to improve the effectiveness of heavy metal adsorption by the charcoals.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.32 no.4
• /
• pp.66-73
• /
• 2000

Alkaline sulfite-anthraquinone(AS-AQ) cooking process has been applied to unground pine bark. The properties of the spent liquor such as molecular weight distributions, sulfonic equivalent weights, degree of sulfonation, phenolic hydroxyl groups and kaolin dispersing ability have been investigated to evaluate the possibility of using this liquor as concrete additives or binders. In the case of ground bark meal, more than 90% delignification was achieved at the optimal cooking conditions. However, applying these conditions on unground bark the delignification was slightly retarded. The decrease in the degree of delignification may be attributed to less penetration and diffusion of chemicals during the cooking of the bark. Increasing the cooking temperature only by $5^{\circ}C$ improved the delignification of the bark and about 90% delignification can be achieved. These results indicate that bark can be used successfully during AS-AQ cooking without any mechanical or physical pretreatment. The properties of lignin or polyphenol sulfonates in the spent liquor after AS-AQ cooking of the bark were compared with Sunflo-R, which is commercial lignosulfonate(CLS) prepared from wood. The weight average molecular weights(Mws) estimated by gel-filteration chromatography was found to be ranging from 1,200~1,800. These are considerably lower than those in CLS. Lignin or polyphenol sulfonates in the spent liquor of bark and CLS have similar degree of sulfonation, but the phenolic hydroxyl group was 1.8 times higher than CLS. Moreover, the dispersing abilities of the spent liquors were better than that of CLS, especially after 0.1% addition to kaolin suspension.