Efficient Using Durian Shell Hydrolysate as Low-Cost Substrate for Bacterial Cellulose Production by Gluconacetobacter xylinus.

Durian is one important tropical fruit with high nutritional value, but its shell is usually useless and considered as waste. To explore the efficient and high-value utilization of this agricultural and food waste, in this study, durian shell was simply hydrolyzed by dilute sulfuric acid, and the durian shell hydrolysate after detoxification was used for bacterial cellulose (BC) production by Gluconacetobacter xylinus for the first time. BC was synthesized in static culture for 10 days and the highest BC yield (2.67 g/L) was obtained at the 8th day. The typical carbon sources in the substrate including glucose, xylose, formic acid, acetic acid, etc. can be utilized by G. xylinus. The highest chemical oxygen demand (COD) removal (16.40%) was obtained at the 8th day. The highest BC yield on COD consumption and the highest BC yield on sugar consumption were 93.51% and 22.98% (w/w), respectively, suggesting this is one efficient bioconversion for BC production. Durian shell hydrolysate showed small influence on the BC structure by comparison with the structure of BC generated in traditional Hestrin-Schramm medium detected by FE-SEM, FTIR, and XRD. Overall, this technology can both solve the issue of waste durian shell and produce valuable bio-polymer (BC).

Recent advances and industrial viewpoint for biological treatment of wastewaters by oleaginous microorganisms.

Recently, technology of using oleaginous microorganisms for biological treatment of wastewaters has become one hot topic in biochemical and environmental engineering for its advantages such as easy for operation in basic bioreactor, having potential to produce valuable bio-products, efficient wastewaters treatment in short period, etc. To promote its industrialization, this article provides some comprehensive analysis of this technology such as its advances, issues, and outlook especially from industrial viewpoint. In detail, the types of wastewaters can be treated and the kinds of oleaginous microorganisms used for biological treatment are introduced, the potential of industrial application and issues (relatively low COD removal, low lipid yield, cost of operation, and lack of scale up application) of this technology are presented, and some critical outlook mainly on co-culture method, combination with other treatments, process controlling and adjusting are discussed systematically. By this article, some important information to develop this technology can be obtained.

Echocardiographic assessment and guidance in minimally invasive surgical device closure of perimembranous ventricular septal defects.

BACKGROUND: The primary aim of this study was to explore the safety and feasibility of minimally invasive surgical device closure of perimembranous ventricular septal defects (PMVSDs) in children using echocardiography for preoperative assessment and intraoperative guidance. METHODS: We enrolled 942 children diagnosed with PMVSDs from April 2010 to October 2013. All children underwent full evaluation by transthoracic echocardiography (TTE) and multiplane transesophageal echocardiography (MTEE) to determine the sizes, types and spatial positions of defects and their proximity to the adjacent tissues. The PMVSDs were surgically occluded using MTEE for guidance. RESULTS: Eight hundred eighty-nine (94.37%) of 942 children underwent successful closure of PMVSDs. Symmetric devices were used in 741 children (including 38 A4B2 occluders) and asymmetric devices were used in the other 148. All patients received follow-ups at regular intervals after successful occlusion. The occluders remained firmly in place. No noticeable residual shunt or valvular regurgitation was discovered, with the exception of one child whose original mild aortic regurgitation progressed to moderate by the 18 month follow-up. Overall there were no significant arrhythmias with the exception of 3 children, all of whom experienced postsurgical acute attacks of Adams-Stokes syndrome. CONCLUSIONS: Minimally invasive surgical device closure of PMVSDs is safe and feasible. TTE and MTEE play vital roles in all stages of treatment of PMVSDs.

Single cell oil production from low-cost substrates: the possibility and potential of its industrialization.

Currently, single cell oils (SCO) attract much attention because of their bi-function as a supplier of functional oils and feedstock for biodiesel production. However, high fermentation costs prevent their further application, and the possibility and potential of their industrialization is suspected. Therefore, various low-cost, hydrophilic and hydrophobic substrates were utilized for SCO production. Of these substrates, lignocellulosic biomass, which is the most available and renewable source in nature, might be an ideal raw material for SCO production. Although many reviews on SCO have been published, few have focused on SCO production from low-cost substrates or evaluated the possibility and potential of its industrialization. Therefore, this review mainly presents information on SCO and its production using low-cost substrates and mostly focuses on lignocellulosic biomass. Finally, the possibility and potential of SCO industrialization is evaluated.