• Journal of Korean Society on Water Environment
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• v.21 no.5
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• pp.484-489
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• 2005

In order to determine the removal rate of non-biodegradable substances and the change of their structural properties, this study was carried out by an ozone-treatment experiment on leachate collected from the landfill area of D City in Chung chung nam-do and examined the change of the chemical properties of non-biodegradable substances. The main elements of non-biodegradable substances in landfill leachate were benzene, toluene, trichloroethane, trichloroethylene, xylene, etc. and the concentration of toluene was 15.7 mg/L on the average, benzene 7.2 mg/L, trichloroethane 1.1 mg/L, trichloroethylene 0.75 mg/L and xylene 0.5 mg/L. When leachate was treated with ozone for 10 min, 30 min and 60 min, UV absorbance was reduced with the increase of reaction time, and the reduction rate was 38.6% at 60 min. TOC was removed by 13.2% at 60 min. The low reduction rate of TOC may be because TOC reacts indirectly with OH radical produced from reaction with ozone while UV absorbance usually relies on direct reaction between organic matters and ozone molecules. Color was removed by up to 97%, which suggests that ozonation is highly effective in removing coloring elements in leachate. Sixteen kinds of non-biodegradable compounds were found in the leachate and most of them had the characteristic of aromatic hydrocarbon. Among them dibutyl phthalate was identical with a substance included in the list of US EPA, which is classified as a mutagen that may cause the mutation of genes and disorders in chromosomes. In addition, 2,5-Cyclohexadiene-1,4-dione, 1,2-Benzenedicarboxylic acid and butyl octyl ester were found to be similar to substances listed by USEPA. According to the result of analyzing structural changes before and after ozonation using GC-MS, cyclic compounds and aromatic compounds were observed in the original water and aliphatic compounds were newly observed after ozonation. In addition, through ozonation, humic substances of high molecular weight were oxidized and decomposed and produced low-molecular compounds such as aldehyde, ketone and carboxyl acid and highly biodegradable aliphatic carbon, which suggests the bio-degradability of non-biodegradable substances.

• The Journal of Korean Medicine
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• v.26 no.3 s.63
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• pp.27-42
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• 2005

Objectives : Alzheimer's disease (AD) is a progressive and fatal neurodegenerative disease characterized by amyloid plaques and neurofibrillary tangles. These plaques are associated with degenerating neuronal processes and consist primarily of fibrillary aggregates of beta-amyloid$ protein, generated from amyloid precursor protein (APP). Another amyloidogenic fragment, the carboxyl terminus (CT) of APP, which is composed of 99-105 amino acid residues containing the complete $A{\beta}$ sequence, also appears to be toxic to neurones. Recent evidence suggest that CT105, carboxy terminal 105 amino acids peptide fragment of APP, may be an important factor causing neurotoxicity in AD. Methods : Although a variety of oriental prescriptions including Pinelliae rhizoma have traditionally been utilized for the treatment of AD, their pharmacological effects and action mechanisms have not yet been fully elucidated. In the present study, we investigated effects of the dichloromethane extract of Pinelliae rhizoma (PINR) on neurotoxicity and the formation of reactive oxygen species (ROS) and nitric oxide (NO) in SK-N-SH cells overexpressed with CT105. In addition, we evaluated its radical scavenging activity and effects on acetylcholinesterase (AChE) activity. Furthermore, effects on cognitive deficits induced by scopolamine treatment in rats were evaluated. Results ; We found in this study that PINR significantly inhibited apoptotic neuronal death induced by CT105 overexpression in SK-N-SH cells. Based on morphological examinations by phase-contrast microscopy, PINR reversed apoptotic changes of CT105-expressed cells. It was also found that PINR significantly promoted neurite outgrowth and inhibited formation of ROS nd NO. PINR was shown to scavenge DPPH radicals and noncompetitively inhibit AChE activity. Furthermore, it reduced scopolamine-induced memory impairment in rata, assessed by passive avoidance test. Conclusions : Taken together, these results demonstrate that PINR exhibits neuroprotective, antioxidant, and memory enhancing effects, and therefore may bs beneficial for the treatment of AD.