Hemoglobin Improves Sophorolipid Production in O-13-1 Under Oxygen Limited Conditions.

Sophorolipids (SLs) are homologous microbial secondary metabolites produced by and have been widely applied in many industrial fields. The biosynthesis of SLs is a highly aerobic process and is often limited by low dissolved oxygen (DO) levels. In this study, the hemoglobin (VHb) gene was transformed into O-13-1 by homologous recombination to alleviate oxygen limitation.

Bioavailability of dissolved organic nitrogen and its uptake by Ulva prolifera: Implications in the outbreak of a green bloom off the coast of Qingdao, China.

To investigate bioavailability of dissolved organic nitrogen (DON) and its contribution to nitrogen demand for Ulva prolifera, a cruise was conducted during a bloom of U. prolifera in Qingdao coastal waters, China, dissolved inorganic nitrogen (DIN) and DON components were investigated. Uptakes of both DIN and DON by U.

[Potential Bioavailability of Dissolved Organic Nitrogen in the Discharge Outlets of Sewage Treatment Plants Around the Jiaozhou Bay].

Dissolved organic nitrogen (DON) is an important portion of total dissolved nitrogen (TDN) transported to the coastal from land-based sources and its bioavailable moieties of DON are regarded as potentially important nitrogen sources for eutrophication in coastal environments. Based on the four field observations conducted in July, November 2012 and in March, May 2013 at the four sewage treatment plants (STPs) around the Jiaozhou Bay (JZB), the concentrations and compositions of total dissolved nitrogen (TDN) as well as total dissolved amino acids (TDAA) were analyzed, and the ratio of dissolved organic carbon (DOC) to DON and the composition and abundance of amino acids were regarded as indexes to evaluate the bioavailability of DON in STPs around JZB. The concentrations of TDN ranged from 413.

[Effects of Oil Pollutants on the Performance of Marine Benthonic Microbial Fuel Cells and Its Acceleration of Degradation].

Degradation of oil pollutants under the sea is slow for its oxygen-free environment which has caused long-term harm to ocean environment. This paper attempts to accelerate the degradation of the sea oil pollutants through electro catalysis by using the principle of marine benthonic microbial fuel cells (BMFCs). The influence of oil pollutants on the battery performance is innovatively explored by comparing the marine benthonic microbial fuel cells ( BMFCs-A) containing oil and oil-free microbial fuel cells (BMFCs-B).

[Studies on micelle behaviors of sophorolipid biosurfactant by steady-state fluorescence probe method].

The critical micelle concentration (CMC) of sophorolipid was determined by steady-state fluorescence probe method in which pyrene was used as fluorescence probe. Meanwhile, the changes in the sophorolipid CMC were examined in the addition of NaCl and aliphatic alcohol, respectively. The results showed that the CMC of sophorolipid was 1.

[Evaluation on biodegradability of hydrocarbon biomarkers in two crude oils under laboratory conditions].

Biodegradabilities of several hydrocarbon biomarker groups, including isoprene, hopanes and steranes in a medium-crude oil BZ34-1 and a heavy-crude oil SZ36-1 from offshore, were determined under laboratory conditions. The results of GC-MS analysis showed that isoprene biomarkers such as pristane and phytane in both crude oils degraded obviously in 60-day experiment period. The degradation ratios of pristane and phytane in the medium-crude oil BZ34-1 reached 20.

[Role of irradiance on the seasonality of Skeletonema costatum Cleve blooms in the coastal area in East China Sea].

With field culture experiments and model calculations, the role of light on why in both spring and summer Skeletonema costatum Cleve blooms can occur in the coastal area in East China Sea were studied. The results show that the growth optimal light intensity (I(opt)) of S. costatum increases gradually to a maximum of 121.

[Effects of irradiance on blooms of the dinoflagellate Prorocentrum donghaiense Lu in the coastal area in East China Sea].

With field culture experiments and model calculations, the natural-light-dependent growth and the optimal light layers in sea water for growth of red tide dinoflagellate Prorocentrum donghaiense Lu were studied in order to analyze the role of light on algal blooms in the coastal area in East China Sea in spring. The results show that the relationship of growth and light can be well described by Steele's equation, and the optimal light intensity (Iopt) of P. donghaiense is (38.