Kwontack Hwang

Stimulatory Effects of Ferulic Acid on Endurance Exercise Capacity in Mice

Ferulic acid was orally administered to mice in order to investigate its effects on exercise endurance capacity. When a single administration of ferulic acid was given to the mice in an adjustable-current water pool, the duration of exhaustive swimming was longer than that exhibited by the mice in the control group. Also, when the mice were exhaustively exercised for 3 consecutive days, no change in swimming time was found in the ferulic acid-administered group on the final day, and a large decrease in the untreated mice. Administration of ferulic acid efficiently activated the hepatic antioxidative defense system during exercise. The mice that received ferulic acid showed significant increases in the activity of hepatic antioxidant enzymes such as superoxide dismutase, catalase, and glutathione-S-transferase. Furthermore, an increased glutathione level was observed, while the malondialdehyde content was reduced. These results suggest that ferulic acid possesses stimulatory effects that can enhance exercise endurance capacity and reduce fatigue by elevating antioxidative potentials.

Inhaled essential oil from Chamaecyparis obtuse ameliorates the impairments of cognitive function induced by injection of β-amyloid in rats.

Context: Chamaecyparis obtusa Sieb. & Zucc., Endlicher (Cupressaceae) forest bathing or aromatherapy has been shown in various studies to have biological functions such as anticancer, antiallergies, antiinflammatory, and antioxidant activity. However, no reports exist on the pharmacological or biological activities of the essential oil of C. obtusa (EOCO) or its effects on central nervous system. Objective: The aggregation and formation of β-amyloid peptides (Aβ) into fibrils are central events in the pathogenesis of Alzheimer’s disease (AD), and overproduction and aggregation of Aβ into oligomers have been known to trigger neurotoxicity. In this study, we investigated the effects of inhaled EOCO on cognitive function and neuronal apoptosis in rats intrahippocampally injected with Aβ. Materials and methods: To model AD, 4 μg of aggregated Aβ was injected into the hippocampus. To test the effects of EOCO, behavioral performance in the Morris water maze was tested 4 days after injection. After behavioral testing, brain sections were prepared for TTC staining and TUNEL assay. Results: Inhaled EOCO protected spatial learning and memory from the impairments induced by Aβ1–40 injection. In addition, the behavioral deficits accompanying Aβ1–40-induced AD were attenuated by inhalation of EOCO. Furthermore, acetylcholinesterase (AChE) activity and neuronal apoptosis were significantly inhibited in rats treated with Aβ1–40 and EOCO compared to rats treated only with Aβ1–40. Discussion and conclusion: EOCO suppressed both AD-related neuronal cell apoptosis and AD-related dysfunction of the memory system. Thus, the results of this study support EOCO as a candidate drug for the treatment of AD.

Physicochemical Characteristics and Antioxidant Activities of Luffa cylindrica (L.) Roem

Physiochemical characteristics of Luffa cylindrica (L.) Roem and antioxidant activities of its four extracts were analyzed. The chemical composition of L. Roem contained 93.69% moisture, 1.64% crude fiber, 0.52% crude protein, 0.27% crude fat, and 0.06% crude ash. The major minerals were potassium, phosphrous, and calcium. We also analyzed the major organic acids, acetic acid and succinic acid. In free amino acids, -aminoisobutyric acid showed the highest concentration (100.74 mg/100 g), followed by phosphoethanolamine, urea, asparagine, and valine. Glutamic acid was the highest hydrolyzed amino acid with 1,039.99 mg/100 g followed by aspartic acid, lysine, and arginine. Four extracts from L. Roam, hot-water (LCH), cold-water (LCC), 80% ethanol (LCE), and methanol (LCM), were prepared. Total phenolic and flavonoid levels of LCE exhibited higher than three extracts. The antioxidant potential of extracts from L. Roem were investigated using DPPH, ABTS, and NBT assays. Of the four extracts, LCE had relatively high antioxidant capability on DPPH and superoxide anion radical scavenging activities (12.13%, 16.88%, and 26.61%). Based on the above results, it is suggested that an 80% ethanolic extract from L. Roem was a natural antioxidant material for health food and should be a good ingredient for functional food.

Enrichment as a screening method for a high-growth-rate microalgal strain under continuous cultivation system

Microalgae are a promising feedstock for renewable biodiesel production. High productivity of biodiesel production from microalgae is directly related to growth rate as well as lipid content of cells. In the present study, an enrichment process in a continuous cultivation system was developed to screen a high-growth-rate microalga from a mixed culture of microalgal species; Chlorella vulgaris, Chlorella protothecoides, and Chlamydomonas reinhardtii were used as test organisms for our experiments. The time-dependent washout of mixed microalgal pool was executed to successfully enrich the C. reinhardtii, which exhibits the higher growth rate than C. vulgaris and C. protothecoides under turbidostat conditions within 75 h. The domination of C. reinhardtii in the mixed culture was validated by on-line monitoring of growth rate and flowcytometric analysis. For the time-efficient production of microalgal biomass, this screening process has a high potential to segregate the fast-growing microalgal strains from the pool of various uncharacterized microalgal species and random mutants.

Cost-efficient cultivation of Spirulina platensis by chemical absorption of CO2 into medium containing NaOH

Spirulina is one of the promising photosynthetic microorganisms as the source for food, cosmetic, and other value-added products such as phycocyanin. However, its production cost associated with cultivation is expensive because of high concentration of bicarbonate (76wt%) in standard Zarrouk medium for Spirulina. Bicarbonate not only acts as a carbon source but also helps maintaining culture medium in alkaline condition, which is essential for growth of Spirulina. The present study demonstrates that bicarbonate (16.8 g/L) in standard Zarrouk medium was completely replaceable by chemical CO2 absorption using 0.2M NaOH and 154.2 mmol CO2 gas could be absorbed in the form of NaHCO3/Na2CO3 into 1 L medium during the process. This process was incorporated into Spirulina cultivation, which enabled us to reduce the total cost of preparation of Zarrouk medium by 34.3% without sacrificing biomass and pigments production. In addition, another important use of NaOH is achievement of cost-efficient and ecofriendly sanitization of culture medium.

Prevention of ethanol-induced hepatotoxicity by fermented Curcuma longa L. in C57BL/6 mice

The protective effect of fermented Curcuma longa L. (FC) was investigated in male C57BL/6 mice under ethanol-induced oxidative stress. Ethanol markedly elevated levels of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in mice. However, mice receiving FC prior to ethanol treatment did not display hepatotoxicity as evidenced by the significant reductions of AST and ALT activities. When compared to the ethanol-alone treated group, FC group exhibited a significant decrease in cytochrome P-450 2E1 (CYP2E1) activity, an enzyme associated with oxidative stress. Indicators of the hepatic antioxidant defense system, such as levels of superoxide dismutase, catalase, glutathione reductase and glutathione were also increased in FC-pretreated mice. The amelioration of malondialdehyde was indicative of the protective effect of FC against liver damage mediated by ethanol. These results suggest that FC could be a candidate used for the prevention against alcoholic liver diseases by the alleviation of oxidative stress via suppressing CYP2E1.