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The marine microalga Chlorella sp. was cultivated under mixotrophic conditions using methanol as an organic carbon source, which may also act to maintain the sterility of the medium for long-term outdoor cultivation. The optimal methanol concentration was determined to be 1% (v/v) for both cell growth and lipid production when supplying 5% CO 2 with 450 µE/m 2 /sec of continuous illumination. Under these conditions, the maximal cell biomass and total lipid production were 4.2 g dry wt/L and 17.5% (w/w), respectively, compared to 2.2 g dry wt/L and 12.5% (w/w) from autotrophic growth. Cell growth was inhibited at methanol concentrations above 1% (v/v) due to increased toxicity, whereas 1% methanol alone sustained 1.0 g dry wt/L and 4.8% total lipid production. We found that methanol was preferentially consumed during the initial period of cultivation, and carbon dioxide was consumed when the methanol was depleted. A 12:12 h (light:dark) cyclic illumination period produced favorable cell growth (3.6 g dry wt/L). Higher lipid production was observed with cyclic illumination than with continuous illumination (18.6% (w/w) vs 17.5% (w/w)), and better lipid production was also obtained under mixotrophic rather than autotrophic conditions. Interestingly, under mixotrophic conditions with 12:12 (h) cyclic illumination, high proportions of C 16:0 , C 18:0 , and C 18:1 were observed, which are beneficial for biodiesel production. These results strongly indicate that the carbon source is important for controlling both lipid composition and cell growth under mixotrophic conditions, and they suggest that methanol could be utilized to scale up production to an open pond type system for outdoor cultivation where light illumination changes periodically.

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The effect of high pressure processing (HPP) on the reduction of microbial growth, dimethylamine (DMA), trimethylamine (TMA) and biogenic amines (BAs) was investigated in semi-dried squid for 28 days at 4C. The semi-dried squid was subjected to 500 MPa for 0 min (HPP-0), 5 min (HPP-5) and 10 min (HPP-10). The number of Morganella morganii and Klebsiella pneumonia in the HPP-10 was less than 1 log cfu/cm 2 throughout the refrigerated storage time. The highest amount (22.16 mg/kg) of DMA was detected in the control, while the lowest amount was 11.19 mg/kg in the HPP-10. The HPP-treated samples revealed noticeably lower amounts (15.41-35.34 mg/kg) of TMA than the control (45.73 mg/kg) after 28 days. The BA content was maintained below the toxic level of 1,000 mg/kg throughout the refrigerated storage. Therefore, HPP could be a promising approach for extending shelf life and improving microbiological safety of semi-dried squid. PRACTICAL APPLICATIONSHigh pressure processing (HPP) has received much attention in recent years due to many benefits over traditional thermal processing. In this study, the HPP effectively retarded the growth of M. morganii and K. pneumonia contributing to BA formation and also inhibited the development of off-flavors such as DMA and TMA in semidried squid. Therefore, the HPP can be applied for ensuring microbiological safety and extend shelf life of semi-dried squid during refrigerated storage.

Trapa japonica shell contains phenolic compounds such as tannins. Studies regarding the antioxidant and anti-adipogenic effects of Trapa japonica shell cultivated in Korea are still unclear. Antioxidant and anti-adipogenic activities were measured by in vitro assays such as 2,2-diphenyl-1-picrylhydrazy (DPPH) radical scavenging activity, 2,2′-azinobis( 3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activity, ferric reducing ability of plasma assay, reducing power, superoxide dismutase-like activity, and iron chelating ability in 3T3-L1 cells. We also measured the total phenol and flavonoids contents (TPC and TFC, respectively) in Trapa japonica shell extract. Our results show that TPC and TFC of Trapa japonica shell extract were 157.7±0.70 mg gallic acid equivalents/g and 25.0±1.95 mg quercetin equivalents/g, respectively. Trapa japonica shell extract showed strong antioxidant activities in a dose-dependent manner in DPPH and ABTS radical scavenging activities and other methods. Especially, the whole antioxidant activity test of Trapa japonica shell extract exhibited higher levels than that of butylated hydroxytoluene as a positive control. Furthermore, Trapa japonica shell extract inhibited lipid accumulation and reactive oxygen species production during the differentiation of 3T3-L1 preadipocytes. Trapa japonica shell extract possessed a significant antioxidant and anti-adipogenic property, which suggests its potential as a natural functional food ingredient.