Antimicrobial potential of carvacrol against Edwardsiella piscicida in vitro.

With the alarming rise of antibiotic-resistant bacteria, novel antibacterial substances are urgently needed for controlling and treating multidrug-resistant bacterial infections. Edwardsiella piscicida is an important zoonotic enteric pathogen, that can cause systemic hemorrhagic septicemia in fish. Carvacrol, a major terpene of oregano essential oil, has a wide range of antibacterial activities.

Strategies to enhance production of metabolites in microbial co-culture systems.

Increasing evidence shows that microbial synthesis plays an important role in producing high value-added products. However, microbial monoculture generally hampers metabolites production and limits scalability due to the increased metabolic burden on the host strain. In contrast, co-culture is a more flexible approach to improve the environmental adaptability and reduce the overall metabolic burden.

Natural Sunlight-Mediated Emodin Photoinactivation of .

can be a substantial concern, as it causes various diseases in aquaculture. An effective and green method for inhibiting is urgently required. Emodin, a naturally occurring anthraquinone compound, was exploited as a photo-antimicrobial agent against .

Alterations of Plasma Biochemical and Immunological Parameters and Spatiotemporal Expression of TLR2 and TLR9 in Gibel Carp () after CyHV-2 Infection.

Cyprinid herpesvirus II (CyHV-2), a highly contagious pathogen of gibel carp (), causes herpesviral hematopoietic necrosis disease (HVHND) and enormous financial losses. However, there is limited information available regarding the changes in plasma biochemical and immunological parameters and the response characteristics of Toll-like receptor 2 (TLR2) and Toll-like receptor 9 (TLR9) in gibel carp after CyHV-2 infection. To address this knowledge gap, a sub-lethal CyHV-2 infection was conducted in gibel carp, and the sample was collected daily from 1 to 7 days post infection.

Carvacrol Inhibits Quorum Sensing in Opportunistic Bacterium .

Bacterial quorum sensing (QS) plays a crucial role in chemical communication between bacteria involving autoinducers and receptors and controls the production of virulence factors in bacteria. Therefore, reducing the concentration of signaling molecules in QS is an effective strategy for mitigating the virulence of pathogenic bacteria. In this study, we demonstrated that carvacrol at 15.

Predation of Cyclopoid Copepods on the Theronts of : Shedding Light on Biocontrol of White Spot Disease.

White spot disease, caused by the parasitic ciliate , is a significant threat to the freshwater fish farming industry worldwide, resulting in massive mortality and economic losses. Eliminating the free-swimming theronts from the culture environment is considered crucial for the control of infection. It is well-documented that planktonic ciliates are valuable food resources for macro-zooplankton in aquatic ecosystems.

In Vitro Antibiofilm Activity of Resveratrol against .

is a Gram-negative bacterium that widely exists in various aquatic environments and causes septicemia in fish and humans. Resveratrol, a natural polyterpenoid product, has potential chemo-preventive and antibacterial properties. In this study, we investigated the effect of resveratrol on biofilm formation and motility.

Effects of glycyrrhetinic acid β on growth and virulence of .

is a significant pathogen to freshwater farmed animals, and antibiotics are usually used to control the bacterial septicemia caused by . Due to the severe situation of development and spread of antibiotic resistance, there are stricter restrictions on antibiotics used in aquaculture. To evaluate the feasibility of glycyrrhetinic acid β (GA) as an alternative therapy against bacterial infection, in this study, an isolated from diseased fish is used to test the antibacterial, anti-virulence activity and therapeutic effect of GA and , respectively.

QseBC regulates in vitro and in vivo virulence of Aeromonas hydrophila in response to norepinephrine.

The inter-kingdom communication between host and pathogenic bacteria mediated by the host hormones epinephrine (Epi)/norepinephrine (NE)/autoinducer-3 (AI-3) and transduced by the bacterial two-component signal transduction system QseBC has been well demonstrated in mammalian pathogens. Aeromonas hydrophila, a common opportunistic pathogen in freshwater aquaculture, responds to NE by increased bacterial growth and enhanced virulence. However, the underlying mechanisms remain poorly understood.

Protective Effects of Total Flavones on Liver Injury Induced by in Tilapia ().

Clinical studies have confirmed that total flavones (GTFs) have good anti-hepatic injury, but whether they have a good protective effect on anti-hepatic injury activity induced by in tilapia () is unknown. The aims of this study were to investigate the protective effects of total flavones on liver injury induced by (SA) and its underlying mechanism in fish. A total of 150 tilapia were randomly divided into five groups, each with three replicates containing 10 fish: normal control group, infection group, and three total flavone treatment groups (addition of 0.

Antimicrobial and Antivirulence Activities of Carvacrol against Pathogenic .

is a ubiquitous Gram-negative opportunistic pathogen in the freshwater environment and the most common cause of bacterial septicemia in aquaculture. In this study, we investigated the impact of carvacrol, a natural monoterpenoid found in herbs, on the virulence of in vitro and the antibacterial effect in combination with antibiotics. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of carvacrol against NJ-35 were 125 µg/mL and 250 µg/mL, respectively.

The erection of a new genus, Neotegorhynchus n. g. (Palaeacanthocephala, Illiosentidae), with a redescription of Neotegorhynchus cyprini n. comb. from Cyprinus carpio from the Yangtze River basin, China.

The present paper summarizes acanthocephalan parasites of the family Illiosentidae Golvan, 1960, collected from the intestine of common carp (Cyprinus carpio L.) from Taihu Lake in Wuxi, Jiangsu Province, China. A total of 21 acanthocephalan specimens were found in 6 carps (prevalence of 35%).

Characterization of the complete mitochondrial genome of Yamaguti and Miyata, 1940 (Cestoda: Nippotaeniidae).

In this study, we report the first complete mitochondrial genome of the tapeworm in the order Nippotaeniidea Yamaguti, 1939. This mitogenome, which is 14,307 base pairs (bp) long with an A + T content of 72.2%, consists of 12 protein-coding genes, 22 transfer RNA (tRNA) genes, two rRNA genes, and two non-coding regions.

Paeonol increases the antioxidant and anti-inflammatory capacity of gibel carp (Carassius auratus gibelio) challenged with Aeromonas hydrophila.

Paeonol, a naturally occurring polyphenol isolated from medical plant, has been known to exhibit anti-oxidative and anti-inflammatory effects. In order to evaluate the effect of paeonol on Carassius auratus gibelio infected by pathogenic bacteria Aeromonas hydriphila. 750 fish were randomly divided into 5 groups, which separately treated with 0.

Tributyrin Plays an Important Role in Regulating the Growth and Health Status of Juvenile Blunt Snout Bream (), as Evidenced by Pathological Examination.

The present study aimed to assess the role of tributyrin (TB) in regulating the growth and health status of juvenile blunt snout bream () through an 8-week feeding experiment. Six groups were fed experimental diets with added TB percentages of 0% (control group), 0.03%, 0.

Molecular cloning and functional characterization of the hypoxia-inducible factor-1α in bighead carp (Aristichthys nobilis).

HIF-l is the earliest documented and most widely studied hypoxia-inducible factor (HIF) and plays a key role in the cell hypoxia signal transduction pathway. Particularly, the HIF-1α protein is sensitive to oxygen and plays a critical role in hypoxia regulation. This study is the first to report on the molecular cloning and characterization of HIF-1α in bighead carp (Aristichthys nobilis; anHIF-1α).

Transcriptomic analysis of oligochaete immune responses to myxosporeans infection: Branchiura sowerbyi infected with Myxobolus cultus.

The Myxozoa are endoparasites characterized by a two-host life cycle that typically involves invertebrates and vertebrates as definitive and intermediate hosts, respectively. However, little is known about invertebrate-myxosporean interactions, particularly about patterns of host immune defense. We used RNA-sequencing to identify genes that are possibly involved in the immune responses of the oligochaete Branchiura sowerbyi naturally infected with Myxobolus cultus.

Effects of dietary fenugreek seed extracts on growth performance, plasma biochemical parameters, lipid metabolism, Nrf2 antioxidant capacity and immune response of juvenile blunt snout bream (Megalobrama amblycephala).

Dietary administration of some plant-derived substances have been proved of great economic value in aquaculture. In order to investigate the effects of dietary fenugreek seed extracts (FSE) on juvenile blunt snout bream (Megalobrama amblycephala), a feeding trial was conducted for 8 weeks. The results showed that final weight (FW), weight gain (WG), feed conversion ratio (FCR) and specific growth rate (SGR) were not significantly affected by dietary FSE levels.

Effects of dietary tryptophan levels on antioxidant status and immunity for juvenile blunt snout bream (Megalobrama amblycephala) involved in Nrf2 and TOR signaling pathway.

Dietary administration of tryptophan has been proved improving growth performance of fish. An 8-week feeding trial was conducted to investigate the effects of dietary tryptophan level on antioxidant capacity and immune response through Nrf2 and TOR signaling pathway. The results showed that, 0.

Morphological variation in Myxobolus drjagini (Akhmerov, 1954) from silver carp and description of Myxobolus paratypicus n. sp. (Cnidaria: Myxozoa).

There is uncertainty in the identification of Myxobolus drjagini, the causative agent of silver carp twist disease, in the literature. An investigation of fish parasites in Lake Taihu, China, revealed several Myxobolus drjagini-like myxosporeans infecting the subcutaneous tissue of the head skin, the olfactory and oculomotor nerves in the cranial cavity, and the intrafilamental epithelium of the gills of silver carp Hypophthalmichthys molitrix (Valenciennes, 1844). Myxospores from the head skin and the nerves were identified as conspecific to M.

Characterization of the complete mitochondrial genome of Xi et al., 2018 (Cestoda, Caryophyllidea).

is a recently described caryophyllidean monozoic tapeworm from schizothoracine fish on the Tibetan Plateau. In the present study, the complete mitochondrial genome of is determined for the first time. The mitogenome is 15,034 bp in length with an A+T content of 59.

Molecular cloning, tissue distribution, and pharmacological characterization of blunt snout bream (Megalobrama amblycephala) melanocortin-5 receptor.

The melanocortin-5 receptor (MC5R) plays an important role in the regulation of exocrine secretion in mammals. Its function in fish is not well established. In this study, we reported the molecular cloning, tissue expression, and pharmacological characterization of Megalobrama amblycephala MC5R (MamMC5R), as well as the effect of catching stress on its expression.

The stress hormone norepinephrine increases the growth and virulence of Aeromonas hydrophila.

Stress is an important contributing factor in the outbreak of infectious fish diseases. To comprehensively understand the impact of catecholamine stress hormone norepinephrine (NE) on the pathogenicity of Aeromonas hydrophila, we assessed variations in bacterial growth, virulence-related genes expression and virulence factors activity after NE addition in serum-SAPI medium. Further, we assessed the effects of NE on A.