Digestive enzyme complex
Cellulase
Cellulase is the name for enzymes that break down cellulose, the main structural fibre of plant cell walls.
Also known as: endoglucanase, cellobiohydrolase, β-glucosidase
What it is
Cellulose is a complex polysaccharide of linked glucose units and a major component of plant cell walls. Cellulases are the enzymes that cut its β-1,4 links, and they work as a team:[1]
- endoglucanases cut long cellulose chains at random points;
- exoglucanases (cellobiohydrolases) release cellobiose from the chain ends;
- β-glucosidases split cellobiose and short cellulose fragments into glucose.
Source [1]
Where it’s found
Unlike amylase, protease and lipase, cellulase is not something a dog’s own digestive system makes. Cellulose is neither digested nor absorbed in the upper gut of mammals; it is broken down only through a partnership with cellulolytic micro-organisms, which in herbivores and omnivores live mainly in the large intestine (and, in ruminants, the rumen). Mammalian genomes encode few carbohydrate-digesting enzymes, and the human ones act on starch and sugars such as lactose and sucrose rather than cellulose.[1]
Cats and dogs, like humans, do not have all the enzymes needed in the small intestine to degrade several types of plant fibre.[2]
Cellulases also occur alongside the main enzymes in some plant extracts — bromelain from pineapple, for example, contains cellulases among its minor components.[3]
Why it’s used in dog supplements
Of the six enzymes on our label, cellulase is the only type a dog does not make at all. Dogs produce amylase, protease and lipase in the pancreas and lactase in the small intestine, but rely on micro-organisms for cellulose breakdown. Cellulase’s substrate is cellulose, the structural material of plant cell walls.[4],[5],[1]
On the DIGEST+ label
The label lists six enzymes in the Digestive Enzyme Complex, 150 mg in total, derived from natural plant sources. The label states that total for the complex as a whole; it does not give a separate amount for each enzyme, so we don’t either. Cellulase is one of the six listed on the DIGEST+ label.
- Amylase
- Bromelain
- Protease
- Lipase
- Cellulase
- Lactase
Questions people ask
Do dogs produce cellulase?
No. Mammals, including dogs, do not digest cellulose with their own enzymes in the upper gut. Cellulose breakdown depends on cellulolytic micro-organisms, mainly in the large intestine.
Is cellulase the same as the cellulose on the label?
No. Cellulase is an enzyme in the Digestive Enzyme Complex. Microcrystalline cellulose is a separate technological additive used in making the tablet; it is cellulose, the fibre cellulase acts on.
How much cellulase is in DIGEST+?
The label gives 150 mg in total for the six-enzyme Digestive Enzyme Complex and does not list a separate amount for cellulase.
Work out your exact supply
The calculator on the product page takes your dog’s weight band and how many dogs you have, then shows the daily dose, how long a bottle lasts and a sensible refill rhythm.
Sources
- Cellulolytic bacteria in the large intestine of mammals — Gut Microbes. Checked 2026-10-15.
- Molecular assessment of the fecal microbiota in healthy cats and dogs before and during supplementation with fructo-oligosaccharides (FOS) and inulin using high-throughput 454-pyrosequencing — PeerJ. Checked 2026-10-15.
- Properties and Therapeutic Application of Bromelain: A Review — Biotechnology Research International. Checked 2026-10-15.
- A review: Pancreatic enzymes in the treatment of chronic pancreatic insufficiency in companion animals — Journal of Veterinary Internal Medicine. Checked 2026-10-15.
- Intestinal Disaccharidase and Alkaline Phosphatase Activity in the Dog — Proceedings of the Society for Experimental Biology and Medicine. Checked 2026-10-15.
Updated