Cyanobacteria in Suspension 50 mL

Quick Answer: Cyanobacteria in Suspension 50 mL is a small bottle of live cyanobacteria (blue-green bacteria) growing in a liquid medium. Biology teachers use a cyanobacteria suspension to show photosynthetic prokaryotic cells under the microscope and to run simple practicals on light, pigments and oxygen.

What Students See in a Cyanobacteria Suspension

Cyanobacteria are bacteria that carry out oxygen-releasing photosynthesis with chlorophyll a, the same pigment plants rely on. Because they are prokaryotes, a wet mount shows cells with no nucleus and no chloroplasts: the photosynthetic membranes lie spread through the cytoplasm. Placing a drop beside a green alga or a moss leaf lets a class compare prokaryotic and eukaryotic photosynthesisers on the same slide session.

Many cyanobacteria also contain phycocyanin, a blue accessory pigment, which explains the older name blue-green algae. Filamentous genera often show heterocysts, larger thick-walled cells in which nitrogen fixation takes place, whereas other genera grow as single cells or loose colonies. The listing does not name the species in this 50 mL bottle, so which of these features a class can find depends on the strain supplied.

Fifty millilitres is enough for many class wet mounts and for starting fresh subcultures in a standard cyanobacterial growth medium such as BG-11, kept under a lamp or on a bright windowsill out of direct sun.

Specifications

Practicals with Live Cyanobacteria

• Comparing prokaryotic and eukaryotic cells, with a drop of the suspension beside a green alga or onion epidermis
• Measuring oxygen change in light and dark with a dissolved oxygen or data-logging probe
• Separating pigments: phycocyanin gives a blue water-soluble extract, while chlorophyll and carotenoids dissolve in acetone or ethanol
• Growing subcultures under different light intensities or colours to compare growth rate
• Looking for heterocysts in filamentous strains during a nitrogen-cycle lesson

Care of the Live Culture

• Open the parcel as soon as it arrives, loosen the cap and keep the cyanobacteria suspension at room temperature in bright indirect light; a live culture should not go in the refrigerator unless the supplier’s sheet says so.
• Use it within a few days, or subculture a few millilitres into fresh sterile medium, because the nutrients in a small bottle run out.
• Follow ordinary microbiology hygiene: no mouth pipetting, hand washing after use and a disinfectant wipe of the bench.
• Before disposal, add a disinfectant such as dilute bleach or autoclave the culture, following your institution’s biological waste rules.

Why Choose LabEquip

School and college biology departments usually order a live culture shortly before a cells or photosynthesis practical, so timing matters more than quantity. LabEquip lists the suspension in its General Lab Products range and can pair it with plain glass microscope slides for the wet mounts; give your practical date through the contact page when you order.

Frequently Asked Questions

Are cyanobacteria bacteria or algae?

They are bacteria. Cyanobacteria are prokaryotes with no nucleus or chloroplasts, but they photosynthesise and release oxygen like plants and algae, which is why they were once called blue-green algae. Chloroplasts are thought to have evolved from ancient cyanobacteria.

How do I make a wet mount from the suspension?

Swirl the bottle gently, take one drop with a clean dropper, place it on a slide and lower a coverslip at an angle to avoid air bubbles. Find the cells with the 10x objective, then move to 40x. Closing the diaphragm a little makes pale cells easier to see.

How long will the culture stay alive?

A small culture is healthiest in the first few days after arrival. Kept in indirect light at room temperature with the cap loosened, it can last longer, but for a practical several weeks away it is safer to subculture into fresh medium a week or two before the lesson.

Is the culture safe for school students?

Cyanobacteria sold for teaching are normally harmless laboratory strains, and ordinary microbiology hygiene is enough: no eating or drinking, no mouth pipetting, hand washing afterwards and disinfection before disposal. Some wild cyanobacteria in lakes produce toxins, so pond blooms should not be handled without supervision.

Which species will I receive?

The species or strain is not named in the listing. If your lesson needs heterocysts for nitrogen fixation, ask for a filamentous strain; if you only need to show photosynthetic prokaryotic cells, most cyanobacteria will do. Confirm the strain when you enquire.

Why do some cyanobacteria look blue-green rather than grass green?

They contain phycocyanin, a blue accessory pigment, alongside green chlorophyll, and the mix gives a blue-green colour. Phycocyanin dissolves in water, so freezing and thawing a sample and letting it stand in water can release a blue extract while chlorophyll stays in the cells.

Last Updated: September 2026