Novel quorum sensing inhibitor Echinatin as an antibacterial synergist against .

A new antibacterial strategy based on inhibiting bacterial quorum sensing (QS) has emerged as a promising method of attenuating bacterial pathogenicity and preventing bacterial resistance to antibiotics. In this study, we screened Echinatin (Ech) with high-efficiency anti-QS from 13 flavonoids through the AI-2 bioluminescence assay. Additionally, crystal violet (CV) staining combined with confocal laser scanning microscopy (CLSM) was used to evaluate the effect of anti-biofilm against .

[Preliminary study on pathogen of Whitmania pigra disease in high temperature environment].

In this paper, on the contrast of healthy leech, the bacterial diversities were analyzed by 16S rDNA sequence analysis of the bacteria of muscle and intestinal tract of Whitmania pigra, the environment water and sediment of cultivating the diseased Wh. pigra in high temperature by high-throughput sequencing to determine the possible pathogenic bacteria of bacterial diseases of Leech in high temperature. The results showed that the original sequence reached over 83 000, and the effective sequences accounted for more than 87%.

[Effects of Cu²⁺ enrichment and release on growth， internal quality and relative gene expression of Whitmania pigra].

The present study explored the effects of Cu²⁺enrichment and release on the growth and internal quality of Whitmania pigra, and the regularity of enrichment and release in different tissues of Wh. pigra. In the range of safe concentration(SC), a certain concentration of Cu²⁺ was added to the Wh.

[Different arousal modes of hibernating Whitmania pigra].

To study the suitable arousal modes of hibernating Whitmania pigra, the biological characteristics, activity of amylase, lipase, and protease as well as morphologic structure of digestive tract were investigated by direct observational method and 3, 5-dinitrosalicylic acid colorimetry, p-nitrophenyl palmitate ester（p-NPP）colorimetry, folin-phenol and histological methods. The results revealed that Wh. pigra activity was increased with increases of the water temperature and prolonging treating duration.

[Effect of Astragali Radix on growth, immunity and related gene expression of Whitmania pigra].

To explore the effect and mechanism of Astragali Radix on growth and immunity of Whitmania pigra, 0, 0.01%, 0.03%, 0.

[Cloning of Guamerin gene in Whitmania pigra and its spatio-temporal expression analysis after ingestion].

The present study cloned wpGuamerin gene from a non-bloodsucking leech (Whitmania pigra), and the bioinformatics analysis of the sequence was performed. Additionally, the effects of feeding duration on the expression profile of the wp Guamerin gene were explored. The results showed that its sequence consisted of 295 nucleotides encoding a peptide of 83 amino acids(Genbank: KX768545), and its relative molecular weight is 9 145.

[Studies on hibernation pivotal temperature of Whitmania pigra].

The biological characteristics, oxygen consumption, oxygen consumption rate, and activities of amylase, lipase and protease of Whitmania pigra at different temperature were studied by using direct observational method, the still water method and 3, 5-dinitrosalicylic acid colorimetry, right-nitrophenyl palmitate ester（ρ-NPP）colorimetry and folin-phenol method.The results revealed that with decreasing water temperature, the daily activity and the daily feeding ration were decreased. As the temperature was lowered to 4 ℃, the head and tail of Wh.

[Effects of harvest and different processing methods on anti-thrombin activity of Poecilobdella manillensis].

The effects of harvest and different processing methods on the anti-thrombin activity of Poecilobdella manillensis were respectively studied. The indicators included processing methods (vacuum freeze drying, fresh homogenate, drying under sunlight, freezing, scalding, baking under different temperatures), different parts (entire body, cephalon, pygidium, exudate) and body weights (≤10, 10-20, 20-30, 30-40, ≥40 g). The anti-thrombin activities of P.

[Effects of stocking density and exchanging water frequency on growth and inner quality of Whitmania pigra].

The effects of stocking density and exchanging water frequency on growth, digestive enzyme activity, anti-oxidative enzyme and inner quality of Whitmania pigra Whitman were evaluated with corresponding measures. The results showed that the eventual biomass, specific growth rate, gained weight rate, activities of amylase, lipase, protease, SOD, CAT, and ALP correlated positively with stocking density and negatively with exchanging water frequency (P<0.05).

Genetic variation in Whitmania pigra, Hirudo nipponica and Poecilobdella manillensis, three endemic and endangered species in China using SSR and TRAP markers.

Leeches are not only important medicinal animals worldwide but also are endangered. We aimed to (i) explore the level of genetic diversity within/among populations of three leeches, (ii) assess genetic differentiation among these three leeches, and (iii) discuss an appropriate strategy for conserving leech germplasm. A total of 315 individuals of Whitmania pigra, Hirudo nipponica and Poecilobdella manillensis from 21 populations were collected in China and Vietnam.