They have the ability to produce some of the bioactive compounds such as antioxidants, antibiotics and toxins, which are widely used in the pharmaceutical industry (García-Casal et al., 2007). This high diversity provides an excellent opportunity to discover new bioactive compounds (Abubakar et al., 2012). Therefore, a lot of research has been done to find an effective tool to prevent or cure the disease (Marimuthu et al., 2015).
Specifically, a large number of microalgae extracts have shown antibacterial, antifungal, antialgal and antiprotozoal activities (Zea-Obando et al., 2018). Due to their photosynthetic nature, their habitat is limited primarily by water depth (Norris et al., 1980). In addition, they can form high concentrations of a variety of pigments such as astaxanthin, zeaxanthin and canthaxanthin (Lubián et al., 2000).
They are 2-3 µm in diameter and have a very simple ultrastructure with reduced structural elements compared to neighboring taxa (Kandilian et al., 2013). The functions of terpenoids are organic synthesis process and recycling of body cells (Yanuhar et al., 2011).
Antimicrobial activity of marine microalgae
Marine microalgae as potential alternative to antibiotics in poultry industry
- Bacterial diseases of poultry in Bangladesh
- Diseases caused by E. coli
- Diseases caused by Stenotrophomonas maltophilia
- Diseases caused by Staphylococcus saprophyticus
- Common antimicrobials used in poultry industry
- Transmission of antimicrobial resistant and risks to public health
- Alternatives to antibiotics
- Marine microalgae as potential alternative to antibiotics
It is one of the most common and economically devastating bacterial diseases of poultry worldwide. Cellulitis, or inflammation of the subcutaneous tissue that also affects the overlying skin, occurs predominantly in broilers and is mainly detected in slaughterhouses. Resistance is a property of the microbe, not the person or other organism infected by the microbe.
Post-transcriptional or post-translational modification of the target of the antimicrobial agent, which reduces the binding of the antimicrobial agent. They generally kill bacteria by inserting themselves into and opening the cell walls, leading to disruption or death of the affected bacteria. Some alternatives to conventional antibiotics can also be used in combination with antibiotics.
This combination can increase the effectiveness of the antibiotic or extend the time an antibiotic can be used before it becomes obsolete. Kang and colleagues studied the effects of replacing antibiotic growth promoter with different forms of Chlorella on performance, immune indices and the gut microfloral population (Kang et al., 2013).
MATERIALS AND METHODS
Culture of microalgae
- Conway medium preparation
- Preparation of microalgae crude extracts
Five milliliters of pure microalgal species from pure stock were added to 15 ml of Conway culture medium in a 50 ml Erlenmeyer flask and were grown under constant environmental conditions. When the stationary phase of the microalgae growth curve was reached, 50 mL of microalgae was transferred to 200 mL of culture medium in a 500 mL Erlenmeyer flask. Vitamin B (thiamine) 200 mg Vitamin B12 (cyanocobalamin) 10 mg. 10 ml/g microalgae) in sterile screw cap bottles for two days at room temperature (Arun et al., 2012).
Isolation and identification of bacteria from chicken samples
- Sample collection from poultry
- Preparation of bacterial culture media
- Preparation of Gram staining solutions
- Isolation and identification of bacteria E. coli
- Gram staining procedure
- Biochemical tests
An amount of 56.58g of XLD agar was suspended in 1000ml of distilled water and heated to boiling point in a hot plate until completely dissolved. An amount of 35.96g of EMB agar was suspended in 1000ml of distilled water and heated to boiling in a hot plate. Collected sample was placed in 10 ml of buffered peptone water in a test tube and incubated for 24 hours at 370C.
The following day, a sample of buffered peptone water was plated on a MacConkey agar plate and an EMB agar plate using an inoculation loop and incubated overnight. Large light pink colonies in MacConkey agar and green metallic sheen colonies in EMB agar confirmed the growth of E. Individual colonies were stained with Gram stain and rod-shaped Gram-negative bacilli were observed under the microscope.
Samples from the overnight incubated peptone water were plated on XLD agar using the inoculation loop and incubated overnight. A single colony was stained with Gram stain, and the rod-shaped gram-negative bacilli with polar flagella were observed under the microscope. Samples from the overnight incubated peptone water were plated on MacConkey agar and blood agar using the inoculation loop and incubated overnight.
Colorless large colonies on MacConkey agar and round, greyish, shiny and non-haemolytic colonies were produced on blood agar. Single colony was stained with Gram's stain and Gram positive round bacteria arranged in grape-like clusters were observed under microscope. The bacterial stock was prepared by mixing glycerin at a final volume of 3% in eppendorf tubes and sealed with paraffin paper and stored at -20°C for further use.
Rinse the slide with a gentle stream of water for a maximum of 5 seconds to remove unbound crystal violet. Rinse the slide with acetone or alcohol for ~3 seconds and rinse with a gentle stream of water. Air dry and observed under microscope Gram positive: Blue/purple color Gram negative: Red color.
- Antimicrobial activity test
- Minimal inhibitory concentration
- Culture of marine microalgae
- Isolation and identification of bacteria
- Escherichia coli
- Stenotrophomonas maltophilia
- Staphylococcus saprophyticus
- Antimicrobial activity test
- Antimicrobial activity of microalgae against E. coli
- Antimicrobial activity of microalgae against Stenotrophomonas maltophilia
- Antimicrobial activity of microalgae against Staphylococcus saprophyticus
- Antimicrobial index of microalgae extract
The cultures tested according to the VITEK 2 GP method within 30 minutes of preparation of the suspended culture. Placed the culture tube and VITEK 2 GP card into the VITEK 2 cassette and consulted the user manual (supplied with the instrument) for instructions on using the instrument. Clear and circular zones were the zones of inhibition produced by the extracts and the zone of inhibition was measured using sliding calipers from one edge of the zone to the other edge.
Microalgae stock solution was added to each of the two replicates to make the concentration 10 mg/ml, 20 mg/ml, 30 mg/ml and 40 mg/ml. The antimicrobial index of the microalgae extract was calculated using the above formula, which was used to compare the antimicrobial effect of microalgae with standard antibiotics. MICs of Chlorella and Tetraselmis extracts grown under different conditions were determined against E.
However, Tetraselmis has been shown to be a major inhibitory alga against Stenotrophomonas maltophilia. The resilience of marine biota to survive in a wide range of marine environments and conditions and the lack of physical defenses or adaptive immunity against pathogens and parasites may have turned them into natural sources of bioactive substances (Bragadeeswaran et al., 2013). The difference in the cell wall structure of Gram-positive and Gram-negative bacteria can control the penetration, binding and antimicrobial activity of a compound (Maligan et al., 2013). In this study, the minimum inhibitory concentration (MIC) of Chlorella and Tetraselmis was determined.
Bioactive compounds from microalgae will need to be studied and identified with chemical structures and beneficial effects to inhibit pathogenic bacteria. Bioactive compounds from microalgae may be suitable for use against other pathogenic bacteria. As we know, there are many species in the genera Tetraselmis, Chlorella and Nannochloropsis, so further studies on a particular species are recommended.
Isolation and identification of microalgae directly from the marine sources was one of the limitations of the current study. Antibacterial activities of extracts of cyanobacteria and green algae isolated from desert soil in Riyadh, Saudi Arabia. Notes on the taxonomy and nomenclature of the algal classes Eustigmatophyceae and Tribophyceae (Synonym Xanthophyceae).
Evaluation of in vitro antibacterial properties of the crude phenolic, alkaloid and terpenoid extracts of Cassia senna L. against human gram-negative pathogenic bacteria. Phosphate-limited growth and uptake kinetics of the marine prasinophyte Tetraselmiss uecica (Kylin) Butcher. 2014), Antibiotic efficacy: balancing conservation against innovation.
APPENDIX
Left) mass culture of microalgae and addition of culture medium, (middle) drying of microalgae extracts in a hot air oven at 60 °C for 12 h, (right) collection of microalgae by centrifugation.
BRIEF BIOGRAPHY OF THE AUTHOR
