• Journal of Life Science
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• v.32 no.8
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• pp.633-640
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• 2022

Recently, kenaf (Hibiscus cannabinus L.) has been highlighted due to its rapid growth in dry, infertile land and its versatile applications in textiles, paper, feed, food, medicine, and phyto-remediation. In Korea, a new cultivar, 'Jangdae', which has the merit of feasible seed-gathering, was established in 2013. However, most of the kenaf seeds used are still imported, and a comparison study of useful bio-activities between Jangdae and imported seeds has not been conducted. In this study, anti-thrombosis, antioxidant and anti-diabetic activities of the ethanol extracts of the Jangdae seed (E-JS) and 8 imported cultivar seeds (E-ICS) were investigated. The E-JS has 14.4 mg/g of total polyphenol and 5.3 mg/g of total flavonoids, whereas the E-ICS has 5.9~8.7 mg/g and 0.7~1.5 mg/g, respectively. Among the 9 kenaf seed extracts, IT 181215 and IT 207877 seed extracts showed 1.92 and 1.88-folds extended thrombin time (TT), and IT 207886 seed extracts showed 3.04-folds extended activated partial thromboplastin time (aPTT). All extracts, except Hong-ma seed, showed 1.36~1.56-folds extended prothrombin time (PT). The E-JS showed strong anti-thrombosis activities with 1.46-folds (TT), 1.38-folds (PT) and 2.37-folds (aPTT) compared to those of solvent controls. The E-JS has the strongest antioxidant activities among the seed extracts, with 0.48 mg/ml of RC₅₀ for ABTS cation and 0.27 mg/ml of RC₅₀ for nitrite scavenging. Meanwhile, the E-JS and IT 181215 extracts showed strong inhibition against α-glucosidase with 10.3~10.6% inhibition at 0.5 mg/ml. Our results suggest the E-JS has potential as an anti-thrombosis, antioxidant and anti-diabetic agent.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.4
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• pp.1-9
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• 2008

The utilization of non-woody fibers with the fast growing annual plants has occurred in the paper industry to replace wood and preserve environment of the earth. The non-woody fibers generally used for papermaking are paper mulberry, gampi, manila hemp, rice straw, bamboo, and coton linter etc.. Recently Kenaf has been spot-lighted for the same application. Kenaf is an annual plant of Hibiscus species of Malvaceae family. Kenaf, a rapid growing and high harvesting non-woody fiber plant, was identified as one of the promising fiber sources for the production of paper pulp. This study was carried out to investigate the pulping characteristics of Kenaf bast fiber for Hanji (traditional Korean paper) manufacturing by different pulping methods, such as alkali, alkali-peroxide and sulfomethylated pulpings. It was possible to make superior grade of Hanji. Especially sulfomethylated pulping was resulted in superior pulp in terms of higher yields and qualities in comparison to those of the other pulping methods. Hanji from sulfomethylated pulp was shown the highest brightness of over 60% and higher sheet strength. In addition, the morphological features of pulp fibers (pulp compositions) affect to the sheet properties. Therefore the effect of fiber distribution index(FDI) which was calculated from the data of Confocal laser scanning microscopy(CLSM) on the sheet properties of Kenaf Hanji was also discussed.

• Journal of agriculture & life science
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• v.45 no.2
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• pp.43-50
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• 2011

Hibiscus cannabinus L. is a plant in the Malvaceae family, that was seeded at June 1st in 2010 and harvested at November 18th. The present study was designated to investigate the safety for host cells, antibacterial effects of Hibiscus cannabinus L. of flower (HCME-F) or leaf (HMEF-L) methanol extract for typical Gram's positive bacteria (St. aureus and Str. epidermidis) or Gram's negative bacteria (S. typhimurium and E. coli). In treatment of different concentrations of HCME-F or HMEF-L (1, 50 and $100{\mu}g/ml$), cytotoxic effects were not shown to RAW 264.7 cells until 24 h incubation. In determination of antibacterial activity of HCME-F or HMEF-L, the antibacterial activities for St. aureus and Str. epidermidis were markedly increased compared to that of untreated control group, but antibacterial activity of HCME-F or HMEF-L for S. typhimurium and E. coli were not changed. Taken together, we demonstrated that methanol extract of HCME-F or HMEF-L showed the safety for RAW 264.7 cells and antibacterial activities for Gram's positive pathogenic bacteria St. aureus and Str. epidermidis. These findings suggest that a methanol extract of Kenaf flower or leaf may be useful alternatives of conventional chemotherapies for dermatitis and mastitis causing Gram's positive pathogens such as Stapylococcus spp. and Streptococcus spp. in domestic animals and humans.

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.620-621
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• 2006

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.622-623
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• 2006

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.426-427
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• 2006

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.2
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• pp.70-76
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• 1999

This study was to measure the potential of nonwoody fibrous material, kenaf. Whole stalk of kenaf, Hibiscus cannabinus was separated by two parts of bast and core portion, and cooked separately by alkaline method. Morphological characteristic was evaluated using confocal laser scanning microscope (CLSM) and fiber quality analyzer(FQA). The strength properties of handsheets, made by different mixing ration between kenaf base and core fibers, were measured. Cross-sectional area of bast fibers was smaller than that of core fibers, but the bast fibers had a thick cell wall and narrow lumen area. Bast fibers were longer in length than core fibers. Core fibers had thin cell walls, broad lumen areas, and short lengths, and they had collapsed shape even in water. These characteristics of core fibers affected strength properties of handsheet positively. When the amount of core fibers increased, the strength properties of handsheet were increased. When the amount of bast fibers increased, the handsheet had rougher surface and higher air permeability.

• Fibers and Polymers
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• v.6 no.2
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• pp.174-179
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• 2005

The present paper studies the effect of chitosan, cationic starch and polyvinyl alcohol (PVA) as sizing agents to enhance surface properties of kenaf paper. The polymers were incorporated into the sheets by spray application. The results clearly showed that the addition of chitosan to a sheet formed from beaten fibers had excellent improvement in surface properties, compared to the effect of other additives. Sizing quality of cationic starch fairly matched with the sizing quality of chitosan, however, it was able to reduce the water absorption potential of paper more than chitosan at a same concentration. In most other properties, particularly the most important property for printing papers, surface smoothness, chitosan-sized papers are superior to the paper sized with cationic starch or PVA.

• Mycobiology
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• v.43 no.3
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• pp.347-350
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• 2015

In September 2013, we discovered sooty mould growing on kenaf with the extrafloral nectaries in Iksan, Korea and identified the causative fungus as Leptoxyphium kurandae based on morphological characteristics and phylogenetic analyses. This is the first report of sooty mould caused by L. kurandae on kenaf in Korea and globally.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.4
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• pp.511-520
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• 2014

Kenaf (Hibiscus cannabinus L.) was recognized as a potential source of forage. To reduce the production cost, we should insure large cultivation area. The one of the best candidate places to expand the useful kenaf production was 'Saemangeum' reclaimed land. To confirm the possibility of kenaf growth in reclaimed land, we seeding and cultivated the kenaf in 'Saemangeum'. The germination percentage of kenaf on 5.0 dS/m soil salinity was 18%. It is less 66% than that of 4.0 dS/m soil salinity and at 6.0 dS/m, the germination percentage of kenaf was under 10%. The growth and development of kenaf in reclaimed land grew worse with increasing soil salinity. The stem diameter which the most important factor that decide the value and yield of product was upper 2.6 cm when soil salinity maintained under 4.0 dS/m, but if soil salinity marked over 4.0 dS/m, the stem diameter of kenaf was drop under 2.0 cm and it deteriorate the number of leaves per plant by 20~46%. The necrosis on older tip and marginal leaves were noted approximately first month after seeding which was correlated directly with the salinity levels of reclaimed soil. Reduction of total yield was coincide with increasing levels of EC. If soil salinity over 5.0 dS/m, the amount of decreased by soil salinity was 51% than that of non-reclaimed region. The allowable soil salinity level of which could be maintained within 20% reduction rate was 4.2 dS/m. Consequently kenaf can be grown successfully with moderately saline soil condition. However, salt levels in excess of 4.2 dS/m severely have restricted plant growth and development and will result in significant yield reduction.