Evaluation of equivalence between different methods for enumeration of fecal indicator bacteria before and after adoption of the new Bathing Water Directive and risk assessment of pollution

The quality of bathing water is of considerable public importance due to the possibility of fecal contamination. In 2009, Croatia implemented the new European Bathing Water Directive (BWD, 2006/7/EC) establishing stricter microbiological standards for new parameters with new reference methods. This study aims to evaluate the equivalence of different methods according to the old and revised BWD and to provide the possibility of data comparison. Furthermore, the directive requires the establishment of the bathing water profile (BWP) for pollution risk assessment. The estimation of consistency of pollution risk assessment with obtained microbiological results was also performed.     

Variation of bacteria biomass and its possible controlling factors in the East China Sea

Two surveys were performed for determining bacteria biomass (BB), temperature, salinity, chlorophyll a (chl-a) and nutrient concentrations at 11 stations with three sampling depths in the high-incidence regions of red tide in the East China Sea (ECS) in the spring of 2006. Temperature and salinity increased from nearshore to offshore region and from high latitude to low latitude in the two cruises of 2006. BB were between 0.3–5.2 mgC m⁻³ (about 2.1 mgC m⁻³ on average) and 0.2–6.0 mgC m⁻³ (about 2.7 mgC m⁻³ on average) respectively in the two cruises. BB in the surface layer decreased from the Changjiang River estuary to high sea and from low latitude to high latitude. The results showed that bacterial growth was regulated by temperature, primary production and inorganic nutrient concentrations depending on different hydrographic conditions. In the surface and middle layers where the primary production can supply enough organic substrate, temperature was the main factor to control bacteria biomass. BB showed a good correlation between the surface and middle layers in both cruises. The distribution of nutrients during both cruises showed a similar decreasing trend from nearshore region and high latitude to offshore region and low latitude. High BB values were mainly recorded from samples in the middle layer where chl-a concentrations were also high, indicating primary production being strongly correlated with temperature over the ECS shelf. In the offshore area, phosphate and silicate became limiting factors for phytoplankton growth with indirect influence on BB. Bacteria played an important role in nitrogen regeneration process turning organic nitrogen to inorganic forms such as NH₄ ⁺. The increasing ratio of NH₄ ⁺/DIN could be a proof of that.     

Origin and biochemical cycling of particulate nitrogen in the Mandovi estuary

Mandovi estuary is a tropical estuary strongly influenced by the southwest monsoon. In order to understand, sources and fate of particulate organic nitrogen, suspended particulate matter (SPM) collected from various locations, was analyzed for particulate organic carbon (POC) and particulate organic nitrogen (PON), δ¹³C_POC, total hydrolysable amino acid enantiomers (l- and d- amino acids) concentration and composition. δ¹³C_POC values were depleted (−32 to −25‰) during the monsoon and enriched (−29.6 to −21‰) in the pre-monsoon season implying that OM was derived from terrestrial and marine sources during the former and latter season, respectively. The biological indicators such as C/N ratio, d-amino acids, THAA yields and degradation indices (DI) indicate that the particulate organic matter (POM) was relatively more degraded during the monsoon season. Conversely, during the pre-monsoon, the biological indicators indicated the presence of relatively fresh and labile POM derived from autochthonous sources. Amino acids such as alanine, aspartic acid, leucine, serine, arginine, and threonine in monsoon and glutamic acid, glycine, valine, lysine, and isoleucine in pre-monsoon were relatively abundant. Presence of bacterial biomarker, d-amino acids in the SPM of the estuary during both the seasons signifies important contribution of bacteria to the estuarine detrital ON pool. Based on d-amino acid yields, bacterial OM accounted for 16-34% (23.0 ± 6.7%) of POC and 29-75% (47.9 ± 18.7%) of PON in monsoon, and 30-78% (50.0 ± 15%) of POC and 34-79% (51.2 ± 13.3%) of the PON in pre-monsoon in the estuary. Substantial contribution of bacterial-N to PON indicates nitrogen (N) enrichment on terrestrial POM during the monsoon season. Transport of terrestrial POM enriched with bacterial OM to the coastal waters is expected to influence coastal productivity and ecosystem functioning during the monsoon season.     

海胆相关菌株抗菌活性筛选及其生物学特性

以8个菌株（3株革兰氏阳性菌、3株革兰氏阴性菌和2株真菌）作为指示菌,采用管碟法对分离自南海硇洲岛马粪海hP-（Hemicentrotuspulcherrimus）中的106株细菌（含放线菌）进行抗菌活性筛选,并对其中抗菌活性较强的菌株进行了基于16SrRNA基因序列的系统发育分析和生物学特性研究。结果显示．具有抗菌活...     

Cultivable bacteria from bulk water,aggregates, and surface sediments of a tidal flat ecosystem

Most-probable-number (MPN) dilution series were used to enumerate and isolate bacteria from bulk water, suspended aggregates, the oxic layer, and the oxic–anoxic transition zone of the sediment of a tidal flat ecosystem in the southern North Sea. The heterotrophic aerobic bacteria were able to grow on agar-agar, alginate, cellulose, chitin, dried and ground Fucus vesiculosus, Marine Broth 2216, palmitate, and starch. MPN counts of bulk water and aggregate samples ranged between 0.18?×?10¹ and 1.1?×?10⁶ cells per milliliter and those of the sediment surface and the transition zone between 0.8?×?10¹ and 5.1?×?10⁷ cells per gram dry weight. Marine Broth and F. vesiculosus yielded the highest values of all substrates tested and corresponded to 2.3–32% of 4,6-diamidinophenyl indole cell counts. Strains of seven phylogenetic classes were obtained: Actinobacteria, Bacilli, α- and γ-Proteobacteria, Sphingobacteria, Flavobacteria, and Planctomycetacia. Only with agar-agar as substrate could organisms of all seven classes be isolated.     

Surface selection,adhesion, and retention behavior of marine bacteria on synthetic organic surfaces using self-assembled monolayers and atomic force microscopy

Adhesion of two marine bacteria Shewanella sp. strain T1 and Pseudoalteromonas sp. strain T8, on differently terminated alkanethiolate self-assembled monolayers on gold was investigated. The selected model surfaces—terminated by CH₃, OH, NH₂, COOH, OH-terminated oligo(ethylene glycol), and methyl-terminated oligo(ethylene glycol)—are characterized by contact angle measurement using water, methylene iodide, 1-bromonaphthalene, and formamide. Surface free energies were calculated. Cell counting of the two bacterial strains on the model surfaces after different times revealed differences between the two strains by at least one order of magnitude. For the different surfaces, the bacteria showed comparably small selectivity. Atomic force microscopy images of adhered bacteria showed very different fingerprints on the different surfaces. Electronic supplementary material  Supplementary material is available in the online version of this article at and is accessible to authorized users.     

荧光显微镜细菌计数方法研究

介绍了细菌荧光显微镜直接计数法的基本原理、仪器设备、分析和计算方法,并对水样过滤操作方法作了一些改进。大量实验数据表明改进的操作方法对实验结果不会产生影响,更加利于对海洋微生物指标的监测。     

厌氧折流板反应器中酸化菌活性研究

本实验将厌氧折流板反应器控制在水解酸化阶段,以比INT脱氢酶活性来表征反应器中各室内的酸化菌活性。探讨了各格室酸化菌活性的变化规律,并对影响各室酸化菌活性的影响因素进行了分析。结果表明,在有机负荷2.4 kgCOD/（m³·d） 条件下,反应器中各室酸化率与酸化菌比INT脱氢酶活性成相关性,一室、二室的酸化率占总酸化率的73%;同一格室内比INT脱氢酶活性中部高于底部。     

渤海湾浅表海水中产低温蛋白酶适冷菌的筛选

从渤海湾浅表海水中分离到１５０株产蛋白酶的低温菌。对其中５析产蛋白酶活力较高的菌株的生长特征和其所产蛋白酶学性质进行了研究。这５株菌的最知生长温度都在２０～２５℃,最高生长温度都在３５～４０℃,属于典型的适冷菌。这５株菌中,ＳＤＭ９９０８的产酶活力最高,为３２０Ｕ／ｍｌ。这５ 菌所产蛋白酶的最适酶活温度均为３５～４０℃。最适ｐＨ在７．０～９．０范围内,为中性或碱性蛋白酶。这些蛋白酶的热稳定性普遍较