This work was designed to investigate the removal efficiency as well as the ratios of toluene and xylene transported from air to root zone via the stem and by direct diffusion from the air into the medium. Indoor plants (Schefflera actinophylla and Ficus benghalensis) were placed in a sealed test chamber. Shoot or root zone were sealed with a Teflon bag, and gaseous toluene and xylene were exposed. Removal efficiency of toluene and total xylene (m, p, o) was 13.3 and 7.0 μg·m(-3)·m(-2) leaf area over a 24-h period in S. actinophylla, and was 13.0 and 7.3 μg·m(-3)·m(-2) leaf area in F. benghalensis. Gaseous toluene and xylene in a chamber were absorbed through leaf and transported via the stem, and finally reached to root zone, and also transported by direct diffusion from the air into the medium. Toluene and xylene transported via the stem was decreased with time after exposure. Xylene transported via the stem was higher than that by direct diffusion from the air into the medium over a 24-h period. The ratios of toluene transported via the stem versus direct diffusion from the air into the medium were 46.3 and 53.7% in S. actinophylla, and 46.9 and 53.1% in F. benghalensis, for an average of 47 and 53% for both species. The ratios of m,p-xylene transported over 3 to 9 h via the stem versus direct diffusion from the air into the medium was 58.5 and 41.5% in S. actinophylla, and 60.7 and 39.3% in F. benghalensis, for an average of 60 and 40% for both species, whereas the ratios of o-xylene transported via the stem versus direct diffusion from the air into the medium were 61 and 39%. Both S. actinophylla and F. benghalensis removed toluene and xylene from the air. The ratios of toluene and xylene transported from air to root zone via the stem were 47 and 60 %, respectively. This result suggests that root zone is a significant contributor to gaseous toluene and xylene removal, and transported via the stem plays an important role in this process.

The aim of the present experiment was to examine hatching rate as a testing tool of porcine embryo viability before early-stage embryo transfer, such as zygotes or 2-cell stage embryos. We evaluated the optimal concentrations and exposure durations of fetal bovine serum (FBS) on porcine parthenotes. Ovaries were obtained from prepubertal gilts at a local abattoir and brought to the laboratory in physiological saline with antibiotics at 30–33°C. The ovaries were washed and wiped, and then cumulus–oocytes complexes (COCs) in the follicular fluid were aspirated from surface-visible follicles (2–6 mm in diameter) with a 10-mL syringe fitted with an 18-gauge needle. After being washed 3 times with modified phosphate-buffered saline (DPBS; GIBCO, Grand Island, NY, USA) containing 0.3% BSA, the COCs were suspended in maturation medium, NCSU-23 containing 10% (v/v) porcine follicular fluid, 10 ng mL−1 epidermal growth factor (EFG; Sigma-Aldrich Corp., St Louis, MO, USA), 10 µg mL−1 follicular stimulating hormone (FSH; Sigma), 35 µg mL−1 luteinizing hormone (LH; Sigma), 1 mg mL−1 cysteine (Sigma, USA), 100 IU mL−1 penicillin G, and 100 µg mL−1 streptomycin sulfate (GIBCO). After 24 h, the COCs were transferred to the same medium without hormones. The oocytes matured for 48 h were denuded. The oocytes with a visible polar body were selected and returned to the maturation medium without hormones. After 65 h of maturation, oocytes were exposed to PBS with 7% ethanol (v/v) for 7 min, and then the oocytes were washed and treated in TCM-199 containing 5 µg mL−1 cytochalasin B (Sigma) for 5 h at 38.5°C in an atmosphere of 5% CO2 and 95% air with high humidity. After cytochalasin B treatment, the presumptive parthenotes were cultured in PZM-5 medium (IFP, Japan) and cleavage of the parthenotes was assessed at 72 h of activation. Normally cleaved parthenotes were cultured for 8 days to evaluate their ability to develop to the blastocyst and hatching stages. The FBS was added at Day 4 or 5 with concentrations of 2.5, 5, or 10%. The blastocyst rates ranged from 39.1 to 70% in each treatment. However, the hatching rate was dramatically decreased in the non-addition group. In this experiment, the developmental potential may be estimated before embryo transfer by an in vitro culture system up to the hatching stage. Table 1. Effect of concentration and exposure duration of FBS on parthenogenetic development of porcine follicular oocytes