Features

Microgen™ Bacillus ID:

Microgen Bacillus ID is a miniaturized biochemical identification system designed to identify those Mesophilic Bacillus spp. and related genera associated with food and beverage spoilage and food poisoning. This identification system comprises 24 biochemical substrates SPECIFICALLY selected and formulated to provide accurate and efficient identification of Bacillus spp.

This product saves time and labor, while improving the accuracy and cost of identification of these organisms. The Microgen™ Bacillus ID employs the most up-to-date taxonomy. Each kit contains suspending medium and sufficient microwell strips for 20 identifications, holding tray, instructions, and reporting cards. Reagents and Identification Software are available separately.

Features:

• Small 24-well test system
• Simple, easy to use and read
• Final result in 48 hours
• Substrates specific for Bacillus
• Based on conventional methods
• Identifies all common species found in food and related samples
• Includes CARBOHYDRATE CONTROL well as reference for color interpretation
• Up-to-date taxonomy

Benefits:

• Confidence in results
• Quick to inoculate and simple to read
• Timely results
• Accuracy and security of reporting correct name
• Reduces errors
• Can cross reference with standard texts
• Cost effective

Easy to use and read:

• Select sufficient colonies from a purity plate
• Emulsify colonies in the suspending medium provided, equivalent to a MacFarland 2
• Inoculate each well of the strips
• Incubate 24 hours at 30°C
• Read and record carbohydrate, ONPG and citrate reactions
• Incubate further 24 hours at 30°C
• Add reagents then re-read strips and record results
• Analyze code with the Microgen Identification System Software

Bacillus Information:

• Clinical contamination includes operating rooms surgical dressings, and in pharmaceutical products.
• Food Spoilage: Bacillus spp. can be isolated from fruits, vegetable products, nuts, spices, cereals, milk and dairy products, meat and dried foods.
• Food Poisoning: Isolates of B.cereus, B.brevis, B.licheniformis, B.subtillis, and B.sphaericus have been found
• Milk and Milk Products: B.licheniformis is a common contaminant of dairy products. Paenibacillus spp., Brevibacillus spp. and Virgibacillus spp. are implicated in spoilage.

Species identified using the Microgen™ ID Bacillus

Bacillus species

• B. cereus group
• B. firmus
• B. badius
• B. laevolacticus
• B. coagulans
• B. lentus
• B. amyloliquefaciens
• B. subtilis
• B. circulans
• B. insolitus
• B. freudenreichii
• B. globisporus
• B. sphaericus
• B. thiaminolyticus
• B. pumilus
• B. licheniformis
• B. megaterium

Vergibacillus species

• V. pantothenticus

Paenibacillus species

• P. polymyxa
• P. macerans
• P. alvei

Brevibacillus species

• Br. brevis
• Br. laterosporus

Procedure

Background Information

The genus Bacillus represents a large and diverse group of species including B. cereus

which is well known as a causative agent of food poisoning. However, many other

species of Bacillus and related genera have over the years also been implicated in

outbreaks of food poisoning. Originally only 16 species of Bacillus were recognized.

However, over the years additional species have been recognized and with the

introduction of molecular methods, the genus Bacillus now includes 123 recognized

species plus an additional 7 genera comprising closely related organisms are now

recognized. Because these organisms are so widely distributed in the environment they

are able to easily contaminate food ingredients and products. In addition, many of these

organisms have been demonstrated to produce toxins capable of causing both diarrhea

and vomiting. It is for this reason that the Microgen Bacillus ID includes not only some

of the mesophilic Bacillus spp. but also some species belonging to Vergibacillus,

Brevibacillus and Paenibacillus. All of the species included in this identification system

have been isolated and/ or reported as causing food spoilage or food poisoning.

Bacillus species and food poisoning

Although B. cereus is the most common species of Bacillus associated with food

poisoning, a range of other species have been implicated in foodborne illnesses. The two

most commonly reported species are B. subtilis and B. licheniformis, these species being

of concern to the food processing and canning industries as they are often implicated as

causes of food spoilage producing potent proteolytic and saccarolytic enzymes. Some

strains of B. licheniformis have been shown to produce toxins. In addition, a range of

other species including B. pumilus, B. brevis and B. thuringiensis, have also been

reported as being the sole species implicated in outbreaks of food poisoning. B. lentus, B.

circulans, B. mycoides, B. polymyxa and B. laterosporus have also been demonstrated to

produce toxins using cell cytotoxicity assays whilst some of these species have also been

shown to produce positive RPLA and TECRA™ assays.

B. subtilis is the most frequently reported species associated with food poisoning other

than B. cereus , being associated with outbreaks involving meat, pastry products, seafood

and rice. Incubation periods varied from 1 – 4 hours, with recovery generally complete

within 24 hours. Symptoms usually included nausea and vomiting, diarrhea was rarely

reported. B. licheniformis associated food poisoning resembles that of C. perfringens, with an incubation period of 6 – 24 hours and symptoms including diarrhea and abdominal pain. In cases of food poisoning associated with B. licheniformis, high numbers of the bacteria 17 (106 cfu/gm) were found in the implicated food (often cooked meat and vegetable dishes) and in the feces of affected persons.

B. pumilus was implicated in 5 outbreaks of food poisoning between 1975 and 1986 in

the UK , in each of these cases only a small number of individuals were involved,

however in each case high numbers > 6 x 106 organisms/ gm were isolated from the

implicated foods in the absence of other recognized foodborne pathogens.

Gilbert et. al. reported 4 instances of food poisoning in which B. brevis was the sole

organism isolated in high numbers from foods implicated in food poisoning outbreaks.

In any investigation of suspected food poisoning in which none of the normal

primary pathogens such as Salmonella, Campylobacter, E. coli, C. perfringens and S.

aureus are isolated Bacillus should always be considered as a potential cause. In

such studies, particularly if the symptoms exhibited by patients include diarrhea,

species other than B. cereus should always be considered.

Literature

 Bacillus ID Color Chart (86.56 kB)

 Bacillus ID Brochure (447.61 kB)

 Foodborne Illness Due To Bacillus Species (130.55 kB)

Specs