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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.

IntroductionCurcuma aromatica Salisb. (Zingiberaceae), indigenous to South Asia, is a robust zingiber with stout underground rhizomes. This wild, aromatic, and attractive turmeric is probably the most useful among the turmeric members for its unique medicinal values. C. aromatica rhizome is a rich source of volatile oil, which consists of several major anti-tumor ingredients including demethoxycurcumin, β-elemene, curcumol, curdione, etc. (Zhou et al., 1997;Dulak, 2005). C. aromatica could promote blood circulation to remove blood stasis and treat cancers and angiogenesis (Kim et al., 2002). The oil infused via the hepatic artery has proven to exert ideal therapeutic effects in humans with primary liver cancer and rats with transplanted hepatoma (Cheng et al., 1999). Curcumin, the most prevalent active secondary ingredient in C. aromatica, acts as a promising agent in the treatment and/or prevention of Alzheimer's disease (Ringman et al., 2005). In addition, the rhizome is Abstract: A rapid and improved micropropagation protocol was developed for Curcuma aromatica, a threatened aromatic medicinal plant, using rhizome sprout as the explant. Stepwise optimization of different plant growth regulators, carbon sources, and basal media was adopted to establish an efficient micropropagation protocol. When cytokinins, such as benzyl amino purine (BAP) or 6-(α,αdimethylallylamino)-purine (2iP), were used either singly or in combination with naphthalene acetic acid (NAA) for shoot induction and multiplication, a single use of BAP was the most effective. As a carbon source, 3% (w/v) sucrose exhibits the greatest promotive effect on shoot initiation and proliferation compared with other carbon sources used. Among the basal media, full strength Murashige and Skoog (MS) media produced the best results, compared to other media studied. By using the most effective treatment from each category, an average of 13.2 shoots/per explant were produced after 6 weeks of culture. Moreover, 85% survival was achieved when rooted explants acclimatized ex vitro using a mixture of sterile sand, soil, and farmyard manure (1:1:1). In addition, antimicrobial activities of rhizome extracts were evaluated. Petroleum ether and chloroform extracts of field-grown rhizome showed potential antimicrobial properties against several human pathogenic bacteria including Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, Shigella sonnei, and Shigella dysenteriae, with a minimum inhibitory concentration (MIC) ranging from 0.03 to 0.5 mg/mL. Thus, the optimized micropropagation protocol may offer large-scale production of plantlets to meet industrial demand for the rhizome. Moreover, our results suggest the rhizome extract of C. aromatica is a promising antimicrobial agent.

In this research, a hybrid anaerobic baffled reactor (HABR) configuration was proposed consisting of a front sedimentation chamber and four regular baffled chambers followed by two floated filter media chambers for the treatment of domestic wastewater. Performance comparison of uninsulated and insulated HABRs was carried out operating at warm temperature (18.6–37.6 °C) under variable HRTs (30 h and 20 h). The study suggests that almost similar chemical oxygen demand (91% vs 88%), total suspended solids (90% vs 95%), turbidity (98% vs 97%), and volatile suspended solids (90% vs 93%) removal efficiencies were obtained for uninsulated and insulated HABRs. Higher removal of total nitrogen (TN) of 41%, NH4+-N of 44%, and NO3−-N of 91% were achieved by the insulated HABR compared to TN of 37%, NH4+-N of 36%, and NO3−-N of 84% by the uninsulated HABR, whereas lower PO43− removal efficiency of 17% was found in the insulated HABR compared to 24% in the uninsulated HABR. This indicated insulation increased nitrogen removal efficiencies by 4% for TN, 8% for NH4+-N and 7% for NO3−-N, but decreased PO43−removal efficiency by 7%.