Biodegradation of dibutyl phthalate in liquid fermentation by endophytic Penicillium species and the toxicity evaluation of the by-product.

The production and use of dibutyl phthalate (DBP) are increasing, and the resulting health and environmental problems are of concern. Therefore, the present study focused on the biodegradation of DBP in liquid fermentation using endophytic Penicillium species and evaluated the cytotoxic, ecotoxic, and phytotoxic effects of the fermented filtrate (by-product). Higher biomass yield was observed in fungal strains grown in DBP-containing media (DM) compared to DBP-free (control) media (CM). The highest esterase activity was observed at 240 h during fermentation with Penicillium radiatolobatum (PR) grown in DM (PR-DM). As per gas chromatography/mass spectrometry (GC/MS) results, the PR degraded 99.986 % of DBP after 288 h of fermentation. Furthermore, compared to DM treatment, the fermented filtrate of PR-DM demonstrated negligible toxicity in HEK-293 cells. Besides, the treatment of PR-DM in Artemia salina indicated >80 % viability and showed a trivial ecotoxic effect. However, compared to the control, the fermented filtrate of PR-DM treatment resulted in ~90 % of the roots and shoots growth of Zea mays seeds, indicating no phytotoxicity. Overall, the findings of this study suggested that PR can degrade DBP in liquid fermentation without generating toxic byproducts.

De Novo Transcriptome Sequencing of Codonopsis lanceolata for Identification of Triterpene Synthase and Triterpene Acetyltransferase.

Codonopsis lanceolata (Campanulaceae) is a perennial plant commonly known as the bonnet bellflower. This species is widely used in traditional medicine and is considered to have multiple medicinal properties. In this study, we found that shoots and roots of C. lanceolata contained various types of free triterpenes (taraxerol, ß-amyrin, α-amyrin, and friedelin) and triterpene acetates (taraxerol acetate, ß-amyrin acetate, and α-amyrin acetate). The content of triterpenes and triterpene acetates by GC analysis was higher in the shoot than in the roots. To investigate the transcriptional activity of genes involved in triterpenes and triterpene acetate biosynthesis, we performed de novo transcriptome analysis of shoots and roots of C. lanceolata by sequencing using the Illumina platform. A total of 39,523 representative transcripts were obtained. After functional annotation of the transcripts, the differential expression of genes involved in triterpene biosynthetic pathways was investigated. Generally, the transcriptional activity of unigenes in the upstream region (MVA and MEP pathway) of triterpene biosynthetic pathways was higher in shoots than in roots. Various triterpene synthases (2,3-oxidosqualene cyclase, OSC) participate to produce triterpene skeletons by the cyclization of 2,3-oxidosqualene. A total of fifteen contigs were obtained in annotated OSCs in the representative transcripts. Functional characterization of four OSC sequences by heterologous expression in yeast revealed that ClOSC1 was determined as taraxerol synthase, and ClOSC2 was a mixed-amyrin synthase producing α-amyrin and ß-amyrin. Five putative contigs of triterpene acetyltransferases showed high homology to the lettuce triterpene acetyltransferases. Conclusively, this study provides the basis of molecular information, particularly for the biosynthesis of triterpenes and triterpene acetates in C. lanceolata.

Development of Multilayer Transducer and Omnidirectional Reflection Model for Active Reflection Control.

Underwater detection is accomplished using an underwater ultrasonic sensor, sound navigation and ranging (SONAR). Stealth to avoid detection by SONAR plays a major role in modern underwater warfare. In this study, we propose a smart skin that avoids detection by SONAR via controlling the signal reflected from an unmanned underwater vehicle (UUV). The smart skin is a multilayer transducer composed of an acoustic window, a double-layer receiver, and a single-layer transmitter. It separates the incident signal from the reflected signal from outside through the time-delay separation method and cancels the reflected wave from the phase-shifted transmission sound. The characteristics of the receiving and transmitting sensors were analyzed using a finite element analysis. Three types of devices were compared in the design of the sensors. Polyvinylidene fluoride (PVDF), which had little effect on the transmitted sound, was selected as the receiving sensor. A stacked piezoelectric transducer with high sensitivity compared to a cymbal transducer was used as the transmitter. The active reflection control system was modeled and verified using 2D 360° reflection experiments. The stealth effect that could be achieved by applying a smart skin to a UUV was presented through an active reflection-control omnidirectional reflection model.