Antibiofilm activity substances derived from coral symbiotic bacterial extract inhibit biofouling by the model strain Pseudomonas aeruginosa PAO1.

The mitigation of biofouling has received significant research attention, with particular focus on non-toxic and sustainable strategies. Here, we investigated quorum sensing inhibitor (QSI) bacteria as a means of controlling biofouling in a laboratory-scale system. Approximately, 200 strains were isolated from coral (Pocillopora damicornis) and screened for their ability to inhibit quorum sensing (QS).

Anti-quorum Sensing Activities of Selected Coral Symbiotic Bacterial Extracts From the South China Sea.

The worldwide increase in antibiotic-resistant pathogens means that identification of alternative antibacterial drug targets and the subsequent development of new treatment strategies are urgently required. One such new target is the quorum sensing (QS) system. Coral microbial consortia harbor an enormous diversity of microbes, and are thus rich sources for isolating novel bioactive and pharmacologically valuable natural products.

[Roles of microbes in matter cycles in phycosphere niche.].

Phytoplankton is the main driver of marine primary production and matter cycles. Their ecological functions have closely linked to the associated microbes. Although microbial biodiversity is high in all kinds of algal hosts (such as dinoflagellate, diatoms and blue-green algae), some he-terotrophic bacteria (Alphaproteobacteria, Gammaproteobacteria, Flavobacteria, and Actinobacteria) often appear as the dominant communities.

[Sapflow characteristics of Kandelia obovata and their controlling factors in Zhangjiang estuary, China.].

In this study, the Grainer's thermal dissipation probe method was applied to monitor sap flux density (SFD) of a mangrove species Kandelia obovata over a period of one year (2010-10-2011-10) in Zhangjiangkou Mangrove National Nature Reserve, Fujian, China. The results showed that both season and diameter class exerted significant effects on the SFD of K. obovata trees.

Koningiopisins A-H, Polyketides with Synergistic Antifungal Activities from the Endophytic Fungus Trichoderma koningiopsis.

Eight new fungal polyketides named koningiopisins A-H (1-8) and four previously known polyketides (9-12) were isolated from the endophytic fungus Trichoderma koningiopsis YIM PH 30002. Their structures were elucidated using extensive spectral data interpretation, and their antifungal and synergistic activities were also evaluated. Koningiopisin C (3) exhibited in vitro antifungal activity against the phytopathogenic fungus Plectosphaerella cucumerina with an MIC of 16 µg/mL.

[Current status of mangrove germplasm resources and key techniques for mangrove seedling propagation in China].

Mangrove germplasm and nursery operation are the foundations of all mangrove ecological restoration projects. Based on the existing literatures and our own experiences, and by using cluster analysis and other methods, this paper assessed the current status of the mangrove germplasm resources and the key techniques for mangrove seedlings propagation in China. In China, the mangrove communities could be divided into 4 types, including low temperature tolerant widespread type, widespread type, thermophilic widespread type, and tropical type, and the mangrove distribution sites could be divided into 5 regions, i.

Effects of environmental stresses on the responses of mangrove plants to spent lubricating oil.

The influence of different environmental stresses, including salinity (5-35‰), tidal cycle (6/6, 12/12 and 24/24 h of high/low tidal regimes) and nutrient addition (1-6 times background nitrogen and phosphorus content) on Bruguiera gymnorrhiza and Aegiceras corniculatum grown in sediment contaminated with spent lubricating oil (7.5 L m(-2)) were investigated. The oil-treated 1-year-old mangrove seedlings subject to low (5‰) and high (35‰) salinity had significantly more reduction in growth, more release of superoxide radical (O2·-) and higher activity of superoxide dismutase (SOD) than those subject to moderate salinity (15‰).

Hydrogen sulphide enhances photosynthesis through promoting chloroplast biogenesis, photosynthetic enzyme expression, and thiol redox modification in Spinacia oleracea seedlings.

Hydrogen sulphide (H(2)S) is emerging as a potential messenger molecule involved in modulation of physiological processes in animals and plants. In this report, the role of H(2)S in modulating photosynthesis of Spinacia oleracea seedlings was investigated. The main results are as follows.

Screening of PAH-degrading bacteria in a mangrove swamp using PCR-RFLP.

There are abundant PAH-degrading bacteria in mangrove sediments, and it is very important to screen the high efficiency degraders in order to perform bioremediation of PAH polluted environments. In order to obtain the more highly efficient PAH-degrading bacteria from a mangrove swamp, we first obtained 62 strains of PAH-degrading bacteria using traditional culture methods and based on their morphological characteristics. We then used the modern molecular biological technology of PCR-RFLP, in which the 16S rDNA of these strains were digested by different enzymes.

Antioxidant tannins from stem bark and fine root of Casuarina equisetifolia.

Structures of condensed tannins from the stem bark and fine root of Casuarina equisetifolia were identified using MALDI-TOF MS and HPLC analyses. The condensed tannins from stem bark and fine root consist predominantly of procyanidin combined with prodelphinidin and propelargonidin, and epicatechin is the main extension unit. The condensed tannins had different polymer chain lengths, varying from trimers to tridecamer for stem bark and to pentadecamer for fine root.

[Temporal and spatial variations of soil respiration in an Artemisia ordosica shrubland ecosystem in Kubuqi Desert].

Based on the dynamic measurements of soil respiration using a closed dynamic chamber and its related environmental factors in a desert shrubland ecosystem regularly during the growing season (May-September) of 2006, we studied the diurnal and seasonal variations of soil respiration of two different land cover soils and their responses to soil temperature, soil water content and biotic factors. The objective was to evaluate the temporal and spatial patterns of soil respiration and their responsible factors in Artemisia ordosica shrubland in Kubuqi Desert, Inner Mongolia, China. The diurnal variation of soil respiration showed an asymmetric single-peak pattern, with the peak value occurring around 12:00.

Leaf respiratory CO is C-enriched relative to leaf organic components in five species of C plants.

•  Here, we compared the carbon isotope ratios of leaf respiratory CO (δ C ) and leaf organic components (soluble sugar, water soluble fraction, starch, protein and bulk organic matter) in five C plants grown in a glasshouse and inside Biosphere 2. One species, Populus deltoides, was grown under three different CO concentrations. •  The Keeling plot approach was applied to the leaf scale to measure leaf δ C and these results were compared with the δ C of leaf organic components.