Lysophosphatidic acid (LPA) is an important signaling molecule which mediates many different cellular responses. The purpose of this study was to investigate the effect of in vitro culture (IVC) medium supplemented with LPA on the preimplantation embryonic development of porcine embryos derived from in vitro fertilization (IVF). Embryos derived from IVF were cultured in PZM-3 medium supplemented with 30 μM LPA on Day 1 to Day 7, Day 1 to Day 3 (early stage), or Day 4 to Day 7 (late stage), or without LPA. Moreover, the messenger RNA (mRNA) expression of obtaining blastocysts from each group were analyzed. Data were analyzed by ANOVA followed by Duncan using SPSS (Statistical Package for Social Science) mean ± SEM. There was a significantly higher cleavage rate in Day 1 to Day 7 than control (71.25% and 57.46%, respectively) and significantly higher total cell number of blastocysts in Day 1 to Day 3 and Day 4 to Day 7 than control (56.07,56.53 and 45.19, respectively). The results also showed that the mRNA expression level of PCNA, Bcl-2 and Bax in Day 1 to Day 7 group blastocysts were significantly higher than control and the expression level of Bax in Day 1 to Day 3 was also significantly higher than control. Moreover, it also showed that Bcl-2/Bax mRNA ratio in D1-3 group was significantly lower than control but D4-7 and D1-7 groups were comparable to control group. In conclusion, our results suggest that treatment with 30 μM LPA during IVC improves the porcine early embryo cleavage and the blastocyst total cell number after IVF and regulating the mRNA expression of blastocysts during blastocyst formation.

Oxalic acid has a nematicidal activity against the root-knot nematode Meloidogyne incognita. High producer of oxalic acid was isolated, and then named as Aspergillus niger F22. Oxalic acid production was investigated under various temperatures from 20 – 33oC and rotational speeds in 5 L jar fermenters. Yield of oxalic acid increased with decreasing temperature. The highest yield was obtained at 23oC, showing the yield of oxalic acid of 8.7 g/L, whereas oxalic acid production was least at 33oC. At 20oC, the yield was lower than that of 23oC. At a rotational speed of 300 rpm, serious oxygen depletion was present from 48 - 72 h, resulting in low productivity of 26.2 mg /L·h. When a rotational speed was set at 600 rpm, dissolved oxygen tension was over 40% and oxalic acid production increased up to approximately 55%. Viscosity during the culture differed with temperatures. Viscosity increased with the increment of temperatures. When A. niger F22 was cultured at 23oC, viscosity was 810 cP, which was favorable for oxalic acid production.

An unbalance of rice productions and consumptions caused serious problems in both of agricultural area and grain market of korea. In recently, various efforts for rice processing products such as rice noodles and rice wines are in progress to overcome the unstable rice market. Among them, waxy rice is predominant items in processing rice. However, varietal features of starch viscosity are not considered in the processing industries and rice breeding field. In this study, 12 waxy rices and 2 cultivars Ilmibyeo(japonica) and IR72(Indica) were studied for physicochemical and amylogram to characterize the use of waxy rices. The amylose contents of waxy rices were from 7.1 to 8.1% with soft gel consistency and relatively low alkali digestion value(1.4% KOH) compare to Ilmibyeo. In the amylogram analysis(RVU) of waxy rices, unlikely normal rices, very fast peak time(about 3.5 min.) was obtained compare to that of 6.2 min. of Ilmibyeo. And 2 to 3 groups were classified based on peak viscosity and consitency of RVU. Wangchal, Odorokimochi and Hangangchal showed relatively high peak viscosity seemed not suitable for rice cake due to the hardness speed. And most of waxy rices developed in korea were believed to be suitable for oil fried cakes(Hankwa) because of a certain grade of starch degradation speed. And Mochiminori and Midoromochi originated from japan could be a good sources in waxy rice breeding program to improve the cooking properties especially in slow down of hardness speed with very low peak viscosity, hot viscosity and cool viscosity.