Peptidohydrolase

Synopsis

Peptidohydrolases (Peptidases / Proteolytic Enzymes) as Dietary Supplements

Nomenclature and Terminological Note

The term peptidohydrolase is a formal biochemical classification term, not the name of a single, discrete natural ingredient. According to the Nomenclature Committee of the International Union of Biochemistry and Molecular Biology (NC-IUBMB), it is recommended that the term "peptidase" be used as synonymous with "peptide hydrolase" for any enzyme that hydrolyses peptide bonds. In the IUBMB Enzyme Nomenclature system, peptidohydrolases occupy the subclass EC 3.4 — "Acting on Peptide Bonds" — representing the entire class of enzymes that cleave peptide bonds. Peptidases, or peptide hydrolases, are enzymes able to hydrolyze peptide bonds; they comprise exopeptidases and endopeptidases, where the former act only near the ends of polypeptide chains and the latter act within those chains.

In dietary supplement commerce, the term "peptidohydrolase" rarely appears on product labels. Instead, individual members of this enzyme class — chiefly bromelain, papain, pancreatin, trypsin, chymotrypsin, and serrapeptase — are used, often in combination blends. This encyclopedic article covers the peptidohydrolase/peptidase class comprehensively, with detailed treatment of its principal supplement-relevant members.

Identity: Biochemical Classification, Synonyms, and Nomenclature

Peptidases, also referred to as peptide hydrolases or peptidyl-peptide hydrolases, are enzymes responsible for the hydrolysis of peptide bonds within peptides and small proteins. The term "peptidase" refers to an enzyme which cleaves a protein or peptide, and it may be used interchangeably with protease, proteinase, oligopeptidase, and proteolytic enzyme.

The usage of "peptidase" as now recommended by IUBMB is synonymous with "protease" as it was originally used — a general term for both exopeptidases and endopeptidases; previously, in Enzyme Nomenclature (1984), "peptidase" was restricted to the enzymes included in sub-subclasses EC 3.4.11–19, the exopeptidases. The term "proteinase," used previously for enzymes included in sub-subclasses EC 3.4.21–99, carried the same meaning as "endopeptidase" and has been replaced by "endopeptidase" for consistency.

The IUBMB classification organizes peptidohydrolases into two major groupings:

Exopeptidases (EC 3.4.11–19): An exopeptidase requires a free N-terminal amino group, C-terminal carboxyl group, or both, and hydrolyses a bond not more than three residues from the terminus. Exopeptidases are further divided into aminopeptidases, carboxypeptidases, dipeptidyl-peptidases, peptidyl-dipeptidases, tripeptidyl-peptidases, and dipeptidases.
Endopeptidases (EC 3.4.21–25, 3.4.99): An endopeptidase hydrolyses internal alpha-peptide bonds in a polypeptide chain, tending to act away from the N-terminus or C-terminus; examples include chymotrypsin, pepsin, papain, and cathepsins. Endopeptidase sub-subclasses include serine endopeptidases (EC 3.4.21), cysteine endopeptidases (EC 3.4.22), aspartic endopeptidases (EC 3.4.23), metalloendopeptidases (EC 3.4.24), and threonine endopeptidases (EC 3.4.25).

Endopeptidases initiate the digestion of food proteins, generating new N- and C-termini that are substrates for exopeptidases that complete the process. Endopeptidases also process proteins by limited proteolysis.

Natural Sources and Principal Supplement-Grade Members

Proteolytic enzymes are natural substances found in the human body and certain plants that assist in digesting proteins. While the body primarily produces these enzymes in the pancreas, they can also be sourced from foods like papaya and pineapple, which contain the enzymes papain and bromelain.

Bromelain (Ananas comosus)

Bromelain is a mixture of proteolytic enzymes primarily extracted from the fruit and stem of the pineapple plant (Ananas comosus). Bromelain extract is a mixture of protein-digesting (proteolytic) enzymes and several other substances in smaller quantities; the proteolytic enzymes are sulfhydryl proteases, where a free sulfhydryl group of a cysteine amino acid side chain is required for function. Bromelain is a mixture of colloids (including proteins, carbohydrates, and mucopolysaccharides), inorganic salts, and simpler organic materials obtained from pineapple (Ananas comosus); it contains at least two proteolytic enzymes and other non-proteolytic enzymes such as acid phosphatase, peroxidase, amylase, and cellulase.

Bromelain is primarily extracted from pineapple stems, a by-product of industrial pineapple processing, which offers a more stable and scalable raw material base, often resulting in better consistency. Originally, bromelain was exclusively derived from Hawaiian pineapple stems, but it is now also manufactured in Taiwan, Thailand, Brazil, and Puerto Rico.

Papain (Carica papaya)

Papain is a proteolytic enzyme obtained from Carica papaya, which also contains chymopapain. Papayas contain an enzyme called papain, also known as papaya proteinase I; papain is found in the leaves, roots, and fruit of the papaya plant. Papain is derived from papaya latex, a natural raw material influenced by geography, climate, harvest timing, and latex collection practices.

Pancreatin (Animal-Derived)

While bromelain and papain come from fruit, chymotrypsin, pancreatin, and trypsin are typically derived from the pancreas of pigs and cows. Pancreatin is traditionally an animal-derived enzyme that works in the small intestine and typically functions at a pH of about 6–8; orally delivered pancreatin must be enterically coated so that it can pass through the acidic stomach without being rendered ineffective.

Microbial and Fungal Proteases

Plant-based fungal pancreatin is able to function in a wider pH range; formulations comprising plant-based fungal pancreatin can be optimized for different pH levels. Fungal fermentation — particularly using Aspergillus species — is a growing source of commercial peptidohydrolase preparations. The Aspergillus niger aspergilloglutamic peptidase has demonstrated potential to hydrolyze plant allergens such as alpha-amylase/trypsin inhibitors in the gastrointestinal system. The Aspergillus niger aspergilloglutamic peptidase (AGP), formerly called aspergillopepsin II, is a unique protease belonging to the peptidase family A4 (EC 3.4.23.19).

Serrapeptase

Serratiopeptidase, a proteolytic enzyme, has been used for almost 40 years in Japan and Europe for pain and inflammation; it is usually available as a fixed-dose combination with various non-steroidal anti-inflammatory drugs (NSAIDs) like diclofenac, aceclofenac, and paracetamol.

Traditional and Historical Use

The use of plant-derived peptidohydrolases in traditional medicine predates their modern biochemical characterization by centuries.

Bromelain / Pineapple

Bromelain has a long history of traditional medicinal use in various cultures, particularly in Central and South America, where pineapple is native. Indigenous peoples in Central and South America, particularly in regions like the Amazon rainforest and the Caribbean, used various parts of the pineapple plant for medicinal purposes, including treating digestive issues, reducing inflammation, and healing wounds. Pineapple was traditionally used for medicinal purposes in South and Central America.

Bromelain was first isolated and described in the late 19th century by researchers in Europe who identified its proteolytic properties; since then, bromelain has gained recognition in both traditional and modern medicine for its potential therapeutic effects. The first isolation of bromelain was recorded by the Venezuelan chemist Vicente Marcano in 1891 by fermenting the fruit of the pineapple.

Papain / Papaya

Papayas contain papain, a proteolytic enzyme that effectively breaks protein down into its amino acids — one reason it has traditionally been used to tenderize meat. For centuries, papaya has been used in traditional medicine to ease digestive troubles, tenderize meat, and support wound healing. The papaya (Carica papaya) originally comes from the American tropics; its name comes from the language of the Arawak Indians, who have long used the papaya as a medicinal plant, and at the beginning of the 16th century, the Spanish began to introduce the papaya and cultivate it in the Antilles and the Philippines.

Modern Medicalization in Europe

Proteolytic enzyme (PE) treatments were first popularized in Germany in the 1960s for inflammation, osteoarthritis, autoimmune diseases, and viral infections. The products typically contain a mixture of pancreatin, papain, bromelain, trypsin, and chymotrypsin.

Key Active Constituents and Mechanisms of Action

The biological activities of supplemental peptidohydrolases stem from their catalytic ability to cleave peptide bonds and from downstream secondary effects on immune and inflammatory mediators.

Proteolytic Activity and Digestion

Proteases are enzymes that catalyze the hydrolysis of peptide bonds, playing a crucial role in metabolic and physiological processes across all organisms; they are classified based on their catalytic mechanism, substrate specificity, and optimal pH conditions, and are essential for functions such as protein recycling, digestion, and zymogen activation. These enzymes are indispensable in numerous biological processes, including digestion, cellular signaling, and protein turnover; in the context of digestion, proteases play a pivotal role in breaking down dietary proteins into smaller peptides and amino acids, facilitating their absorption in the intestines.

When co-ingested with dietary protein, proteases may enhance digestion, increase postprandial plasma amino acid concentration, and affect gut hormones, appetite, and/or satiety.

Anti-Inflammatory Mechanisms

Proteases have anti-inflammatory activity, inhibit platelet aggregation, and inhibit prostaglandins. Preclinical studies indicate that proteolytic enzymes have immunomodulatory and tumoricidal properties; such effects are thought to result from degradation of abnormal immune complexes.

Research in animals with arthritis suggests proteolytic enzymes may help reduce inflammation in the joints and surrounding tissue; the enzymes appear to reduce levels of substances that drive inflammation in the body, including prostaglandins and pro-inflammatory cytokines.

Gut Microbiota Modulation

Research results indicate that fruit proteases have the potential to modulate gut microbiota, with decreasing abundance of Proteobacteria and increasing beneficial Akkermansia muciniphila; enhancement of pancreatic trypsin was observed with bromelain and papain supplementation, while bromelain also increased the thickness of the ileal mucosa.

Topical and Wound-Healing Mechanisms

Naturally occurring proteolytic enzymes such as bromelain, ficin, and papain have gained increasing attention as promising cosmetic and cosmeceutical ingredients due to their exfoliating and skin-resurfacing properties; these enzymes catalyze the hydrolysis of keratin protein bonds, facilitate the removal of dead skin cells from the outermost layer of the epidermis, and promote cell turnover.

Scientific Evidence by Area of Use

1. Digestive Support and Dyspepsia

The most obvious use of proteolytic enzymes is to assist digestion. People with pancreatic insufficiency and cystic fibrosis frequently require supplemental pancreatic enzymes (which include proteolytic enzymes, lipases, and amylases); those with celiac disease or Crohn's disease, and perhaps some people suffering from indigestion, may also be deficient in pancreatic enzymes.

A peer-reviewed randomized, placebo-controlled, double-blind clinical trial published in 2023 assessed a multi-enzyme blend in functional dyspepsia. Functional dyspepsia is a form of dyspepsia lacking clear causes following clinical assessment; dyspepsia is characterized by episodic or persistent abdominal pain or discomfort of the upper gastrointestinal tract, and its onset has been linked with a deficiency or dysfunction of digestive enzymes, suggesting that consumption of digestive multi-enzymatic preparations may be used for the reduction of symptoms. This trial assessed the effectiveness and tolerability of a multi-enzyme blend obtained from fungal fermentation: 120 enrolled subjects (63 male, 57 female), aged 18–59 years, were randomized in a 1:1 ratio to receive either 2 capsules per day of the food supplement (containing 200 mg of the multi-enzyme blend per capsule) or placebo, for 2 months.

One randomized double-blind clinical trial involving 40 patients suffering from digestive upset found that taking a proteolytic enzyme supplement eased digestive symptoms including abdominal pain, belching, bloating, heartburn, and loss of appetite.

In contrast, a small, double-blind, placebo-controlled trial found no benefit from proteolytic enzymes as a treatment for dyspepsia (indigestion). This underlines that the evidence base for digestive applications remains mixed and that trial size and design vary substantially.

A 2024 clinical study from Frontiers in Nutrition examined comprehensive enzyme blends in real-time intestinal samples. This study demonstrated that comprehensive enzyme blends significantly enhanced carbohydrate breakdown and nutrient absorption, with substantial increases in glucose and fructose levels after enzyme supplementation, proving enhanced macronutrient digestion. Evidence strength: Preliminary to moderate; individual well-designed trials exist, but the body of evidence is still small and results are inconsistent.

2. Protein Digestion and Sports Recovery

A proprietary protease blend (ProHydrolase®, Deerland Probiotics & Enzymes) has been studied in human clinical settings. ProHydrolase is supported by two human clinical trials that demonstrate the product's ability to increase amino acid levels in the blood, supporting muscle recovery, as well as decrease C-reactive protein levels, an indicator of inflammation; amino acids in the blood are shown to increase by 20% with the consumption of a whey protein supplement accompanied by ProHydrolase compared with consumption of whey alone.

A randomized, double-blind, placebo-controlled crossover study on microbial protease and whey protein co-ingestion enrolled 24 healthy young adults (12 male, 12 female; mean BMI 23.6; mean age 25 years). Participants consumed whey protein concentrate (25 g protein) containing a mixture of three microbial protease preparations or placebo (maltodextrin); plasma amino acid, glucose, insulin, and appetite regulatory hormone concentrations were assessed at baseline and throughout a 240-minute postprandial period. Evidence strength: Preliminary but promising for protein bioavailability outcomes; sample sizes are small and further replication is warranted.

3. Osteoarthritis and Musculoskeletal Pain

Bromelain was first reported to be of value as an analgesic/anti-inflammatory for use in both rheumatoid arthritis and osteoarthritic patients in 1964. Clinical trials have assessed the effectiveness of bromelain most frequently using preparations containing differing complexes of proteolytic enzymes and differing concentrations of bromelain; three complexes have been used: Phlogenzyme™ (containing bromelain 90 mg/tab, trypsin, and rutin), Wobenzym™ (containing bromelain 45 mg/tab, papain, trypsin, chymotrypsin, pancreatin, lipase, and amylase), and Wobenzym N™ (containing bromelain 45 mg/tab, trypsin, papain, chymotrypsin, pancreatin, and rutin).

A 2022 review looked at nine clinical studies in which people with osteoarthritis took an oral enzyme combination containing bromelain, trypsin, and an antioxidant known as rutin; the authors found the enzyme combination was as effective as non-steroidal anti-inflammatory drugs (NSAIDs) for reducing joint pain and stiffness, with fewer side effects.

Similarly, comparisons with NSAIDs in patients with arthritis suggest that oral therapy with enzyme-antioxidant combinations produces improvement in all major clinical parameters like swelling, pain, and joint stiffness, with comparable efficacy to NSAIDs.

Some evidence suggests proteolytic enzymes can help with arthritis; however, there are not enough data yet to confirm whether proteolytic enzymes reliably and safely work in large numbers of people, and more extensive clinical trials are necessary. Evidence strength: Moderate for pain and function outcomes in osteoarthritis, particularly for multi-enzyme combination products; however, most trials are not large-scale or independently replicated.

4. Post-Surgical and Post-Traumatic Recovery

One study in 24 people who had just undergone dental surgery showed that taking a supplement containing 5 mg of the proteolytic enzyme serrapeptase reduced swelling and pain intensity. Some studies have shown that postoperative treatment with bromelain can help reduce swelling and bruising after cosmetic surgery.

Regarding third molar (wisdom tooth) surgery, the NCCIH has cited a systematic review and meta-analysis of randomized clinical trials assessing bromelain's efficacy on health outcomes after third molar surgery. Bromelain is promoted as a dietary supplement for a variety of purposes including postoperative pain after wisdom tooth extraction, sinusitis, osteoarthritis, and exercise-induced muscle soreness. A small number of studies have been done on the use of bromelain taken orally for reducing symptoms of sinusitis and reducing pain and swelling after wisdom tooth extraction. Evidence strength: Preliminary; the available trials are generally small and of varying quality.

5. Sinusitis and Upper Respiratory Inflammation

Bromelain is also effective at reducing inflammation and relieving symptoms in people with sinusitis, a condition that causes the nasal passages to become inflamed. This claim is based on a limited number of clinical studies; the NCCIH characterizes the evidence for oral bromelain in sinusitis as limited to a small number of studies. Evidence strength: Preliminary; further well-powered trials are needed.

6. Oncology Support

Proteolytic enzymes have not been shown to prevent or treat cancer. Lab studies suggest that proteolytic enzymes can affect the growth of cancer cells; although proteolytic enzymes were previously reported to benefit patients with cancer, more recent studies do not support such claims. Evidence strength: Insufficient for any anti-cancer claim; preclinical data exist but are not substantiated by robust human trials.

7. Immunomodulation

In clinical studies, oral administration of proteolytic enzymes to healthy volunteers resulted in immunomodulatory effects; systemic therapy with proteolytic enzymes before and after exhaustive exercise increased maximal concentric strength and had favorable effects on inflammatory and metabolic markers. Evidence strength: Preliminary; data are based on a limited number of studies in specific populations.

8. Gluten and Allergen Hydrolysis

The Aspergillus niger aspergilloglutamic peptidase has been shown to have great potential to hydrolyze plant allergens such as alpha-amylase/trypsin inhibitors in the gastrointestinal system, as well as in food matrices containing those inhibitors. Research in this area has led to dietary supplement or pharmaceutical compositions comprising Aspergillus niger aspergilloglutamic peptidase and a prolyl-endopeptidase. Evidence strength: Emerging and primarily preclinical/in vitro; human trials are limited.

Body Systems and Health Areas of Association

Gastrointestinal System: As therapeutic supplements, proteolytic enzymes are primarily used to aid digestion, particularly for individuals experiencing protein digestion difficulties due to pancreatic insufficiency or other gastrointestinal disorders.
Musculoskeletal System: Beyond digestive support, proteolytic enzymes have been explored for relief from chronic musculoskeletal pain, osteoarthritis, and post-surgical recovery.
Immune System: Preclinical studies indicate that proteolytic enzymes have immunomodulatory properties.
Integumentary System (Skin): Bromelain, ficin, and papain have gained attention as cosmetic and cosmeceutical ingredients due to their exfoliating properties; these enzymes catalyze the hydrolysis of keratin protein bonds, facilitate the removal of dead skin cells from the outermost layer of the epidermis, and promote cell turnover.
Cardiovascular/Coagulation System: Proteases inhibit platelet aggregation and prostaglandins.
Gut Microbiome: Bromelain and papain are considered promising enzymatic supplementation for beneficial effects on the gut microbiota.

Common Dosage Forms and Dosages Reported in Studies

Proteolytic enzyme supplements are available in capsules, gel caps, chewables, powders, and tablets; some supplements contain a single type of proteolytic enzyme, while others contain a combination.

Enzyme activity is not reliably reflected by weight alone. When choosing a supplement, enzymes are not always measured in milligrams, international units, or other measures of weight; instead they are measured by units of potency and activity, with common units including HUT, USP, and SAP — units regulated under the Food Chemical Codex (FCC) and accepted by the U.S. Food and Drug Administration.

Specific dosages reported in reviewed clinical studies include:

Multi-enzyme blend (fungal fermentation) for functional dyspepsia: 200 mg of the multi-enzyme blend per capsule, 2 capsules per day, for 2 months (n=120, randomized controlled trial).
Phlogenzyme™ for osteoarthritis: Each tablet contains bromelain 90 mg, trypsin 48 mg, and rutin 100 mg.
Wobenzym™ for osteoarthritis: Each tablet contains bromelain 45 mg, papain 60 mg, trypsin 24 mg, chymotrypsin 1 mg, pancreatin 100 mg, lipase 100 mg, amylase 100 mg, and rutin 50 mg.
Bromelain monotherapy: Bromelin™ contains bromelain 200 mg per tablet.
Serrapeptase: Enzyme activity is measured in units; serratiopeptidase 10 mg is equal to 20,000 units of enzyme activity.
Proteolytic enzyme fortified protein supplement (chronic pancreatitis trial): A registered interventional study used proteolytic enzyme with 70,000 Hb unit tyrosine (HUT) fortified with 15 grams of whey protein, given daily for 6 weeks.

Animal-derived pancreatin formulations require enteric coating to survive gastric acid. Orally delivered pancreatin must be enterically coated so that it can pass through the acidic stomach without being rendered ineffective; because enteric coatings may dissolve incompletely, they may reduce the overall activity of the enzyme.

Safety Considerations and Drug Interactions

In terms of safety, proteolytic enzymes are generally considered safe but may cause digestive upset or allergic reactions in some individuals. When taken by mouth, proteolytic enzymes are possibly safe when taken appropriately; side effects are usually mild or moderate and include stomach and intestinal complaints.

Anticoagulant Interactions

People taking warfarin (Coumadin, Jantoven), aspirin, or other drugs that thin the blood should not take the proteolytic enzymes papain or bromelain except under a doctor's supervision. Bromelain may increase bleeding risk due to its antithrombotic effects observed in lab experiments, but clinical relevance is not known. If serratiopeptidase is administered along with warfarin, clopidogrel, or aspirin, as well as with other natural remedies such as garlic, fish oil, and turmeric, there may be an increased risk of bleeding or bruising.

Antibiotic Interaction

When taken with amoxicillin, bromelain was shown to increase absorption of amoxicillin in humans. Bromelain might also cause problems if combined with drugs that thin the blood such as heparin; it should not be mixed with sedative drugs and should be avoided by individuals taking antibiotics because it may increase blood concentrations.

Nutrient Depletion

One proteolytic enzyme, pancreatin, may interfere with the absorption of folate (vitamin B9), so it is advisable to take a folate supplement when taking pancreatin.

Allergenicity

Individuals with bleeding disorders, severe liver or kidney disease, or allergies to pineapple or papaya should exercise caution or avoid use of proteolytic enzyme blends. When applied to the skin, proteolytic enzymes are possibly safe, though some may cause allergic reactions.

Pregnancy

There is not enough reliable information to know if proteolytic enzymes are safe to use when pregnant or breast-feeding; the available guidance suggests staying on the safe side and avoiding use.

Regulatory Status

Although tested in a variety of folk medicine and research models for its possible efficacy against diseases, the only approved clinical application for bromelain was issued in 2012 by the European Medicines Agency for a topical medication (NexoBrid) used to remove dead tissue in severe skin burns. There is no other established regulatory approval for bromelain as a nutraceutical or drug.

Limitations of the Evidence Base

Some studies suggest potential benefits for sports injuries and inflammation, but results have varied widely, with many studies lacking robust design or placebo controls. While proteolytic enzymes show promise for specific uses, further research is needed to establish their efficacy and safety comprehensively. Clinical studies indicate that enzyme needs vary significantly between individuals based on factors including age, digestive health status, and dietary patterns. Furthermore, the variability in the commercially produced product and its diverse ingredients have hindered successful clinical development.