Aquaculture health management demands a constant growth in the production by stabilizing economic loss and implementing various natural plant-based bio products for treating pathogenic bacteria. Pathogenic effects of the Citrobacter freundii isolated from fingerlings of Tilapia collected from a fish farm showed symptoms like tail necrosis, septicemia, hemorrhage, and reddening of the body. Antibacterial activity of C. freundii was tested against various medicinal plants. Of the three plants screened, Azadirachta indica (Neem) showed good antibacterial activity against C. freundii. The present study revealed that A. indica plant extract at a concentration of 150. mg/l in vivo can be used as an alternative to antibiotics for treating this bacterial infection. The use of medicinal plant extract-mediated treatment was found to be very effective in controlling this bacterial infection. © 2014 Elsevier B.V.

Amitava Mukherjee

Centre for Nanobiotechnology

Vellore Campus

John Thomas

Chandra Sekaran N

Thanigaivel S

Vijayakumar S

Gopinath S

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

&nbsp;

&nbsp;

VIT University

Aquaculture

Aquaculture is one of the principal sources to increase the world's fish production. Outbreak of diseases is a major problem in aquaculture. Chemotherapeutic approaches have been used for the treatment and prevention of disease outbreaks. The use of various chemicals has harmful effects on the environment and human health. The prolonged use of antibiotics causes antibiotic resistance. Natural products such as medicinal plants, marine algae, herbs and their extracted compounds are being studied for disease management in fishes and prawns. In this review, the use of seaweeds and their importance in aquaculture health and disease management to control the bacterial infections against the pathogenic bacteria which affect freshwater fishes is explained. Application can either be by a single compound or a combination of two different compounds or as feed additives. Administering the compounds obtained from the extracts in the form of encapsulated beads was found to be more effective. Statement of relevance Seaweeds have good antioxidant capacity and act as a natural medicine. Bacterial fish pathogens affect the health of aquatic organisms. The bioactive compounds from sea weed extracts showed good antibacterial activity. They can be used for treating bacterial infection in aquaculture and as prophylactis. This kind of prophylactic treatment can be used as an alternative to synthetic since they cause resistance. © 2016 Elsevier B.V.

Seaweeds as an alternative therapeutic source for aquatic disease management

Indigenous marine seaweeds and their biological activities have played a significant role in aquaculture especially with regard to their antibacterial and antiviral properties. The bioactive compounds and the toxicity profile of aqueous and ethanol extracts of Padina gymnospora and Sargassum cinereum species were assessed for the treatment of bacterial infection. The optimum exposure to seaweed extracts varied with different concentrations, from 100mg/l to 500mg/l of dried solvent extracts dispersed in 10l of water. It was found to be non-toxic up to 250mg/l. Oreochromis mossambicus infected with Pseudomonas aeruginosa showed abnormal activities like hyperactivity, lethargic movements, hemorrhagic lesions and exophthalmia, with LC 50 values of 1.287, 1.634 and 2.021mg/l for 72, 96, 120h respectively. They were exposed to sea weed extracts of different concentrations. Insignificant mortality was seen in the treated group. PCR and histopathological analysis were done. PCR studies were performed to study the distribution of P. aeruginosa in the tissues of different organs. The results revealed that PCR was positive for gills, while skin showed mild positive, which indicates the presence of the bacteria in these organs. The liver and the kidney were found to be negative.Statement of relevanceThe sea weed extracts are excellent source of antimicrobial compounds. These can be used for treating bacterial infection as an alternative to antibiotics which cause resistance. The extracts are found to be nontoxic and can be used in aquaculture industries for treating bacterial infection.

Investigation of seaweed extracts as a source of treatment against bacterial fish pathogen

Fish diseases caused by Pseudomonas aeruginosa, a known pathogenic organism, is responsible for considerable economic losses in the commercial cultivation of Oreochromis mossambicus (Tilapia). The bacteria were injected into healthy fish through intramuscular injection, oral and immersion challenge. Infection was confirmed by histopathological investigation of the infected organs. Lime nanoemulsion was prepared and the effectiveness of the nanoemulsion was studied both in vitro and invivo by well diffusion assay and invivo in the artificially infected fish. Results showed that the lime nanoemulsion was effective against the P. aeruginosa infection in O. mossambicus both in vitro and in vivo. © 2014 Elsevier B.V.

Colloids and Surfaces B: Biointerfaces

Pathogenecity of Pseudomonas aeruginosa in Oreochromis mossambicus and treatment using lime oil nanoemulsion

Antioxidants are increasingly being recommended because they act directly on oxidative processes and may prevent diseases and problems associated with disease control and aging. Therefore, there is a constant search for antioxidants from natural sources for the isolation of antioxidant biomolecules. Seaweeds are an excellent source of natural antioxidant bioactive compounds which can be used as dietary supplements or as antioxidants in controlling bacterial infection in aquaculture farms as well as in the food industry. A great deal of effort has therefore focused on using available techniques to identify natural antioxidants from seaweeds. The aim of the present study was to analyse the bioactive compounds extracted from ethanol extract of the seaweed Chaetomorpha antennina by GC-MS study and to evaluate its antioxidant and antibacterial activities for controlling bacterial infection in shrimp pathogens through immersion and intramuscular infection study. The antioxidant activity of the selected seaweed was estimated in order to evaluate the efficiency of its ethanol extract since this will help in finding novel bioactive compounds with antioxidant & radical scavenging properties, which in turn can reveal the unexploited properties of this seaweed which could be used in the food and pharmaceutical industry. © 2014 Elsevier B.V.

Antioxidant and antibacterial activity of Chaetomorpha antennina against shrimp pathogen Vibrio parahaemolyticus

Clarias batrachus (Linn) is a species of catfish of the family claridae. Pathogenecity of Aeromonas salmonicida was studied in healthy fish. The inoculum was injected into healthy fingerlings through intramuscular injection and immersion challenge. Histopathological investigation of the infected organs was also studied. The bacterial infection was treated using neem nanoemulsion by in vitro and in vivo analysis and was found to be effective. © 2013 Elsevier B.V.

Studies on pathogenecity of Aeromonas salmonicida in catfish Clarias batrachus and control measures by neem nanoemulsion

Bacterial Fish Pathogens

Miscellaneous Pathogens

Use of plant extracts in fish aquaculture as an alternative to chemotherapy: Current status and future perspectives

In vivo and in vitro antimicrobial activity of Azadirachta indica (Lin) against Citrobacter freundii isolated from naturally infected Tilapia (Oreochromis mossambicus)

Journal	Data powered by TypesetAquaculture
Publisher	Data powered by TypesetElsevier BV
ISSN	0044-8486
Open Access	0