Biotechnology Research International最新文献

Fungicide was an important part in mycopesticides, which play an important role in pest management, while their mass production and commercialization faced problem. We found that the nutrition for mycelia growth and sporulation differences a lot. So, we developed "two-step method" to define the nutrition for sporulation in this paper. The results indicated that the novel method led to a great increase of spore yields for Beauveria bassiana (IBC1201), Lecanicillium lecanii (CA-1-G), and Pochonia chlamydosporia (HSY-12-14), respectively, of about 100, 2, and 16 times and, also reduced the cycle of mass production to 1/3 compared with common time for culturing.

In order to study the effect of nitrite and nitrate on the performance of microbial fuel cell, a system combining an anaerobic fluidized bed (AFB) and a microbial fuel cell (MFC) was employed for high-strength nitrogen-containing synthetic wastewater treatment. Before this study, the AFB-MFC had been used to treat high-strength organic wastewater for about one year in a continuous flow mode. The results showed that when the concentrations of nitrite nitrogen and nitrate nitrogen were increased from 1700 mg/L to 4045 mg/L and 545 mg/L to 1427 mg/L, respectively, the nitrite nitrogen and nitrate nitrogen removal efficiencies were both above 99%; the COD removal efficiency went up from 60.00% to 88.95%; the voltage was about 375 ± 15 mV while the power density was at 70 ± 5 mW/m(2). However, when the concentrations of nitrite nitrogen and nitrate nitrogen were above 4045 mg/L and 1427 mg/L, respectively, the removal of nitrite nitrogen, nitrate nitrogen, COD, voltage, and power density were decreased to be 86%, 88%, 77%, 180 mV, and 17 mW/m(2) when nitrite nitrogen and nitrate nitrogen were increased to 4265 mg/L and 1661 mg/L. In addition, the composition of biogas generated in the anode chamber was analyzed by a gas chromatograph. Nitrogen gas, methane, and carbon dioxide were obtained. The results indicated that denitrification happened in anode chamber.

In vitro experiment was carried out to see the effect of saw dusts of Pinus kesiya, Shorea robusta, and Callicarpa arborea on Trichoderma harzianum, isolate TH-13 mass production, along with its biotization effect on Capsicum chinensis Jacq. "Bhut Jolokia." Early mycelium initiation (2 days) occurred in S. robusta followed by P. kesiya and C. arborea (3.5 days). The sporulation was observed earlier in S. robusta (100% after 6 days) than P. kesiya (33.4% after 8 days) and C. arborea (16.7% after 9 days) but no sporulation was observed in control. The complete sporulation was also earlier in S. robusta (100% after 10 days) than P. kesiya (33.4% after 15 days) and C. arborea (16.4% after 18 days). Higher conidial yield (86 × 10(6)) was also in S. robusta than P. kesiya (70 × 10(6)) and C. arborea (45 × 10(6)), respectively. The increase in height (60-70 cm), number of leaves (600-650), and yield of chili (120-150 fruits) were also more in inoculated C. chinensis seedlings than control. It is concluded that S. robusta saw dust is the best substrate for mass production of compost fungal activator and can be used in nursery practices for quality stock production of various crops/plantations.

We established two Madin-Darby canine kidney (MDCK) cell lines stably expressing human airway transmembrane protease: transmembrane protease, serine 2 (TMPRSS2) and mosaic serine protease large form (MSPL) which support multicycle growth of two H5 highly pathogenic avian influenza viruses (HPAIV) recombinant vaccines (Re-5 and Re-6) and an H9 avian influenza virus (AIV) recombinant vaccine (Re-9) in the absence of trypsin. Data showed that the cell lines stably expressed TMPRSS2 and MSPL after 20 serial passages. Both MDCK-TMPRSS2 and MDCK-MSPL could proteolytically cleave the HA of Re-5, Re-6, and Re-9 and supported high-titer growth of the vaccine without exogenous trypsin. Re-5, Re-6, and Re-9 efficiently infected and replicated within MDCK-TMPRSS2 and MDCK-MSPL cells and viral titer were comparable to the virus grown in MDCK cells with TPCK-trypsin. Thus, our results indicate a potential application for these cell lines in cell-based influenza vaccine production and may serve as a useful tool for HA proteolytic cleavage-related studies.

A comparative study of extruded and ground maize meals as raw materials for the production of regular (12°P) and high gravity (20°P) worts was devised. Extruded water solubility index (WSI) was higher (9.8 percentage units) and crude fat was lower (2.64 percentage units) compared to ground maize. Free-amino nitrogen compounds (FAN), pH, and glucose were evaluated in regular and high gravity worts produced from ground or extruded maize. Extrusion improved glucose content and ethanol yield. In 20°P mashes, extrusion is enhanced by 2.14% initial glucose compared with regular ground mashes. The 12°P and 20°P extruded treatments averaged 12.2% and 8.4% higher ethanol, respectively, compared to the uncooked counterpart. The 20°P worts fermented with Zymomonas mobilis produced 9.56% more ethanol than the 12°P counterpart. The results show that the combination of extrusion and fermentation of 20°P worts improved ethanol yield per kg flour until 20.93%. This pretreatment stimulates Z. mobilis fermentation efficiency.

Zinc finger nucleases (ZFNs) are associated with cell death and apoptosis by binding at countless undesired locations. This cytotoxicity is associated with the binding ability of engineered zinc finger domains to bind dissimilar DNA sequences with high affinity. In general, binding preferences of transcription factors are associated with significant degenerated diversity and complexity which convolutes the design and engineering of precise DNA binding domains. Evolutionary success of natural zinc finger proteins, however, evinces that nature created specific evolutionary traits and strategies, such as modularity and rank-specific recognition to cope with binding complexity that are critical for creating clinical viable tools to precisely modify the human genome. Our findings indicate preservation of general modularity and significant alteration of the rank-specific binding preferences of the three-finger binding domain of transcription factor SP1 when exchanging amino acids in the 2nd finger.

Xenorhabdus indica KB-3, a well-known protease producer, was isolated from its entomopathogenic nematode symbiont Steinernema thermophilum. Since medium constituents are critical to the protease production, the chemical components of the selected medium (soya casein digest broth) were optimized by rotatable central composite design (RCCD) using response surface methodology (RSM). The effects of all five chemical components (considered as independent variables), namely tryptone, soya peptone, dextrose, NaCl, and dipotassium phosphate, on protease production (dependent variable) were studied, and it was found that tryptone and dextrose had maximum influence on protease production. The protease production was increased significantly by 66.31% under optimal medium conditions (tryptone-5.71, soya peptone-4.9, dextrose-1.45, NaCl-6.08, and dipotassium phosphate-0.47 in g/L). To best of knowledge, there are no reports on optimization of medium component for protease production by X. indica KB-3 using RSM and their application in fibrinolysis. This study will be useful for industrial processes for production of protease enzyme from X. indica KB-3 for its application in the field of agriculture and medicine.

The strains of the yeast Metschnikowia pulcherrima have strong biocontrol activity against various microorganisms. Biocontrol activity of M. pulcherrima largely depends on its iron immobilizing pigment pulcherrimin. Biocontrol activity of pulcherrimin producing strain, M. pulcherrima UMY15, isolated from local vineyards, was tested on different molds that cause food spoilage. M. pulcherrima UMY15 was a very effective biocontrol agent against Penicillium roqueforti, P. italicum, P. expansum, and Aspergillus oryzae in in-vitro plate tests. However, the inhibitory activity of M. pulcherrima UMY15 was less effective on Fusarium sp. and A. niger species in biocontrol assays. In addition, M. pulcherrima UMY15 strain completely inhibited the germination and mycelia growth of A. oryzae, A. parasiticus, and Fusarium sp. spores on artificial wounds of apples when they coinoculated with M. pulcherrima UMY15. Moreover, when coinoculated, M. pulcherrima UMY15 strain also inhibited the growth of P. roqueforti, P. italicum, P. expansum, A. oryzae, Fusarium sp., and Rhizopus sp. in grape juice, indicating that M. pulcherrima UMY15 can be used as a very effective biocontrol yeast against various species of postharvest pathogens, including Penicillium, Aspergillus, Fusarium, and Rhizopus.