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The black scraper Thamnaconus modestus was a commercially important fish species in the 1980s, but suddenly its commercial significance decreased in the 1990s mainly due to continuous overfishing. Recently, in order to reverse the depleted stocks of the black scraper and help the species recover, seed production technology has emerged. This has led to the farming of the black scraper in several parts of the southern coast of Korea. Since detailed research on its metabolism in relation to water temperature has been scanty, this was the investigative focus of the present study. The standard metabolism rates of the black scraper (9-10 months old, total length = 22.6 ± 0.8 cm, wet weight = 140.3 ± 13.9 g) were measured at seven different water temperature settings (12, 15, 17, 20, 23, 26, 28 o C) to understand the relationship between metabolism and water temperature. Relationships between water temperature (WT) and oxygen consumption rate (OCR) were obtained as SOCR (weight-specific oxygen consumption rate) = 0.0117WT − 0.0135 (r 2 = 0.9351) and IOCR (oxygen consumption rate per individual) = 1.8160WT − 5.4007 (r 2 = 9428). The Q 10 (temperature sensitivity), an indicator of the sensitivity of biological function to temperature, was analyzed. In our experiment, when the water temperature increased, the Q 10 value decreased. The Q 10 value was 6.27 in waters where the temperature ranged from 12-15 o C and this was much higher than the values obtained in waters where temperatures ranged between (1) 15-23 o C and (2) 23-28 o C. Consequently, it was shown that the black scraper is a warm water species and inhabiting waters in the temperature range from 15-28 o C is deemed appropriate.

Plants are an invaluable source of potential new anti-cancer drugs. Sasa quelpaertensis Nakai (Korean name, Jeju-Joritdae) is one of these plants with medical value, which is a bamboo grass widely distributed in Mt. Halla on Jeju Island, Korea. Here, we investigated the apoptotic effects of S. quelpaertensis leaf extracts in six human cancer cell lines (A549, MCF-7, HepG-2, Hela, HCT116 and A375). MTT assay signified the antiproliferative nature of S. quelpaertensis extracts against all tested cancer cells: S. quelpaertensis displayed slight cytotoxicity against A549, MCF-7 and HepG-2 cells, whereas it was exclusively cytotoxic to Hela, HCT116 and A375 cells. Apoptotic cells were evaluated using PI staining of DNA fragmentation by flow cytometry (sub-G1 peak). PI staining indicated increasing accumulation of Hela, HCT116 and A375 cells at sub-G1 phase. Further events like generation of nitric oxide (NO • ) were accompanied in the S. quelpaertensis Nakai-induced apoptosis. Augmented NO • generation resulted in the DNA fragmentation of Hela, HCT116 and A375 cells by treatment with S. quelpaertensis leaf extracts. These results suggest that S. quelpaertensis may be a potential natural resource for treating cancer cell. To identify the exact mechanisms of molecular mechanism of S. quelpaertensis induced apoptosis awaits further investigation.

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