Latvia’s main natural resource is its fruitful land, but its greatest asset is its people. They have long been united in a powerful synergy, bringing excellent agricultural and wood products to the world.

The exhibition “From Birch Seed to Betulin” is a tribute to one of Latvia’s most common trees – the birch. Since ancient times, Baltic nations have used it in traditional medicine, sung about it in folk songs and made beautiful and practical things out of it.

This also continues today. From a small seed, people grow large birch groves, and the wood is processed in modern factories into products that are widely used around the world. There is no residue in the process – every part of the birch becomes a valuable by-product. This includes the bark from which the biologically active substance betulin is extracted, which has huge potential in pharmaceuticals.

Two species of birch are most common in Latvia: Outdoor birch (also known as woolly birch) and Swamp birch (also known as downy birch).

White birches beyond the river
With silver leaves.
I laid the blanket,
And the silver poured over it.

Distribution of tree species in Latvia​

• Pine – 32%
• Birch – 30%
• Spruce − 19%
• Aspen – 7%
• White alder – 7%
• Black alder – 4%
• Other species – 1%

Source: State Forest Service, 2022

• Most birch stands are in Latgale and Zemgale.
• Birch trees usually grow in mixed stands with spruce and aspen trees.
• Birch trees can reach a height of 30 metres and have a lifespan of 150 years.
• The birch blooms when leaves start to bud, and the flowers are clustered in catkins.
• One kilogram can contain up to 4.5 million birch seeds.
• The birch is a pioneering species in nature; it is the first to enter any open space.
• Two species of birch are most common in Latvia: Outdoor birch (also known as woolly birch) and Swamp birch (also known as downy birch).

Birch grows quickly if properly cared for!

Thanks to the work of Latvian forest scientists in birch selection and the development of cultivation techniques, a birch plantation forest can be established in 40–45 years.

Watch a film about growing birch trees!

Birch is a unique tree with excellent healing abilities. Traditional Latvian and other medicine uses almost all parts of the birch!

Leaves

Birch leaves exude a fragrance when they wilt – they release phytoncides that kill bacteria. This explains the custom of cutting and placing birch bouquets indoors during Whitsun, Midsummer and other celebrations, as a way of promoting good health. Birch bath salts improve blood circulation and destroy pathogens. The leaves are used for joint compresses, kidney and bladder treatments.
Birch leaves contain essential oils (up to 0.05%), flavonglycosides, vitamin C (up to 2.8%), organic acids, tannins (5–9%), saponin (3.2%), arotin, nicotinic acid, glucose, etc.

Buds

Birch buds stimulate bile secretion. The buds are used medicinally in baths to treat inflammation.
Birch buds contain flavonoids, essential oil (up to 6%), resinoids, saponins, vitamin C, organic acids, triterpene alcohols, tannins, bitters, grape sugar, etc.

Tar

Birch tar is extracted from birch bark and twigs in a special dry distillation process that takes place in a closed kiln. It has antiseptic and insecticidal abilities, as well as keratoplastic, keratolytic (corneal softening) and irritant abilities.
Active substances in tar: phenol, xylene, guaiacol, cresol, resin.

Juice

The active birch juice extraction season is March–April; the time before the leaves emerge. The juice harvested in early spring is particularly valuable. It contains sugars, trace elements and other substances that are easily absorbed by the human body.
Birch juice contains fructose, glucose, malic acid, xylitol, proteins, and various trace elements.

The valuable mushroom chaga

The chaga (Inonotus obliquus) is a large black or brown parasitic fungus that tends to grow on living, usually old, birch trunks in areas of mechanical damage. It can grow 40–50 centimetres across and weigh 2–5 kilogrammes. It only grows in the wild, and all attempts to cultivate it have been unsuccessful. It helps to strengthen the body, improve immunity and normalise metabolism, lower blood pressure and blood sugar, restore blood composition and promote blood circulation.
Chaga contains resin, agaric acid, polysaccharides, sterols, iron, manganese, silver, calcium, potassium, phosphorus, triterpenoids.

Charcoal

Charcoal is a type of fuel made by heating wood in the absence of oxygen. This process, known as pyrolysis, breaks down the wood into a black, porous material that consists mostly of carbon. Activated birch charcoal – a long-known and widely used health product – is used as an absorbent to reduce poisoning and bacterial toxins in the body.

Bark

Since ancient times, people have known of the healing and antiseptic properties of birch, which is why birch bark was used to make small dishes and other utensils. The food lasted for longer in them. The top layer of birch bark can be applied to purulent sores as it draws out pus well.

Roots

Birch roots have abilities that help treat rheumatism and reduce fever.

Blossom

An infusion of fresh birch blossom is used for heart disease.

The global climate is changing and the current economic model must change, too. Fossil resources (coal, oil, gas) should be gradually replaced by renewable biomaterials. It is a circular bioeconomy, where wood plays a key role.

Birch wood among us

Birch wood is not only decorative – it also has excellent mechanical properties. It is both highly flexible and durable, as well as has a high thermal capacity. At the same time, birch wood is not resistant to biological aggressors (fungi and bacteria), so untreated it will not be the best choice for outdoor use.

These factors have long determined the main industrial uses of birch wood:

• Furniture
• Energy
• Pulp, paper and articles thereof
• Plywood

From sarcophagus to industry

Historical evidence shows that plywood was used as a material in ancient Egypt. The sarcophagi found in the pyramids are made of primitive plywood, comprised of six layers of glued wood. However, it took almost five millennia for plywood to be produced industrially, with the woodworking industry consolidating its role at the turn of the 19th and 20th centuries.

Baltics – a knowledge and technology hub

The vast resources of birch wood, the development of technology and the expertise of highly qualified engineers paved the way for Latvia and Estonia to become one of the world’s first centres for the development of the plywood industry. The most important use of birch wood in Latvia and the Baltics is the production of plywood. A special technology peels off a thin layer of wood or veneer from birch logs of a certain quality – called veneer logs – which, after drying, are glued together in several perpendicular layers, resulting in a natural, lightweight and highly durable material.

Recycling of residue-free materials into innovative products

Latvijas Finieris Group is Latvia’s largest woodworking company; a world leader in the development, research and production of high added-value birch plywood products. The company employs more than 2 400 people and has veneer and birch plywood plants in Latvia, Lithuania, Estonia and Finland. The wood used is 100% recycled and anything that does not become plywood becomes raw material for the development of other innovative products.

Birch plywood production process

Birch plywood is a wood-based panel material made of three or more layers of peeled plywood glued together. Most often, the direction of the wood fibres in adjacent plies is perpendicular, so the strength of the board is the same in all directions. For specific applications, other materials such as cork or aluminium can also be inserted into the birch plywood layers. The most important added value of birch plywood is obtained when it is coated with various decorative and/or functional finishing materials, such as paint, varnish, veneers of different wood species or impregnated paper film, which provide improved mechanical and decorative properties or protection against mould, pests or fire.

1. Veneer blocks
   A birch log cut to length according to the plywood production technology.
2. Bark
   Approximately 12.5% of the birch trunk is bark, which is mechanically removed during the plywood production process.
3. Hydrothermal treatment of wood
   Before treatment, the birch veneer branches are bathed in a warm bath at ~40 °C for 24 hours.
4. Cross-cutting
   The veneer blocks are sawn to the required dimensions to start peeling.
5. Peeling
   In the peeling machine the veneer is turned into a sheet of veneer in 9 seconds.
6. Drying
   The peeled veneer sheets are dried in special dryers at ~180 °C for ~6 minutes.
7. Applying the glue
   Lignin or phenolic resins are used to glue the veneer sheets together in the plywood board.
8. Parcel collection
   To make the plywood strong, the plywood sheets are laid crisscross to the grain.
9. Cold pressurisation
   To be carried out within 30 minutes after the parcels have been collected to prevent the glue from drying out. The compressed parcel can then wait for hot-pressing for up to 4 hours.
10. Hot pressing
    The hot press presses the plywood sheets together under pressure and temperature. They must cool for 24 hours before trimming.
11. Trimming
    The plywood boards shall be trimmed to the exact dimensions.
12. Sorting
    After trimming, the plywood boards are graded according to precise quality requirements.
13. Quality control
    To ensure that the finished plywood meets the standard requirements, various quality tests are regularly carried out in laboratories.
14. Further processing
    Many plywood products are precision-made plywood parts, made to customer specifications.
15. Packing
    Plywood boards and prefabricated parts are carefully packed before delivery to customers to prevent damage during transport.

1. Special machines separate the inner bark layer, the bast, from the outer bark layer, the sapwood.
2. Then ethanol as a solvent is used for extraction of the ground wood.
3. Evaporation of the alcohol produces a saturated solution, which crystallises to form crystals of birch bark extracts
4. After filtering the crystals, a ‘pie’ of extractions is obtained, which is further dried and ground. The final product is birch wood extracts, with the most valuable ingredient being betulin.

One kilo of premium betulin costs more than € 500!

Betulin Lab

Historically, birch bark has been used in the production of plywood to produce heat, or in simpler terms, burnt. Processing of birch bark into betulin can be done by a company with access to a large volume of birch bark and the ability to invest many millions of euros in new research without an immediate economic return.

In the search for opportunities to add the highest possible value to each cell of wood, the “Latvijas Finieris” birch bark extractive plant “Betulin Lab” was launched in 2022. It was the result of more than six years of research in close collaboration with the Latvian State Institute of Wood Chemistry.

Watch the video

Suberinic acids – a valuable by-product of birch bark extraction

There is virtually no residue in the birch bark extraction process – suberinic acids are extracted in parallel.

It is a unique, natural polymer with great potential to replace synthetic industrial binders used in furniture, particleboard and plywood.

Suberinic acids essentially make it possible to glue tree with tree.

Read more: https://suberbinder.com/

Betulin is a naturally occurring pentacyclic triterpenoid – a crystalline, white organic substance found in birch sap. It is the betulin that gives the birch trunk its white colour. Due to its unique anti-inflammatory, antiviral and antibacterial properties, betulin has huge potential in the pharmaceutical, cosmetic and food industries.
Due to the antibacterial properties of betulin, birch wood naturally decomposes much more slowly than birch wood. Birch bark dry extract also contains lupane, lupeol, betulin acetate, allobetulin, isobetulenol, and oleic acid. Betulin is insoluble in water, which provides additional opportunities for its use in a variety of water-repellent coatings.

Superpowers of Betulin

• Suppresses viral and microbial activity
• Extends life expectancy
• Strengthens immunity
• Fights cancer cells
• Lowers blood cholesterol
• Antimutagenicity
• Promotes skin regeneration

COSMOS Ecocert approval is a highly valued certification in the cosmetics industry, certifying that Betulin Lab’s birch bark extracts, manufacturing process and overall product quality meet strict sustainability criteria and that natural, plant-derived solvents are used in production.

Betulin research in Latvia

Latvian State Institute of Wood Chemistry

More than 10 years ago, the country’s leading wood science centre laid the foundations for betulin research in Latvia.

Senior researchers at the Latvian State Institute of Wood Chemistry Dr.sc.ing. Aigars Pāže and Dr.sc.ing. Jānis Rižikovs are latvian pioneers in the study of complex processing of birch bark. Thanks to the technologies they have developed, 100% of it can be processed into high added value products.

Find out more about the Institute’s biorefinery laboratory research: http://www.kki.lv/laboratorijas/biorafinesanas-laboratorija

Riga Technical University

RTU’s Institute of Organic Chemical Technology regularly conducts research on the potential applications of betulin in pharmaceuticals and cosmetics.

In cooperation with Latvijas Finieris, industrial research is looking for new opportunities to use betulin in polymer technologies and innovative materials.

International studies on betulin

Due to its anticancer, antiviral, antifungal, anti-inflammatory and antibacterial abilities, betulin is a widely studied natural compound worldwide.

Potential future medical applications

• In the treatment of arthritis, including rheumatoid arthritis
• Reducing skin ageing
• In the treatment of neurodegenerative diseases
• Extending life expectancy
• In liver cell protection (hepatoprotection)
• In the prevention of atherosclerosis
• HIV and cancer treatment

Betulin – synthesised in nature, perfected in the lab!

Betulin in supramolecular gels

Betulin is hydrophobic and insoluble in water, so it is poorly absorbed by the body in its natural form, posing a major challenge for its effective use in pharmaceuticals.

Colloidal betulin oleogel

Oleogel is obtained from dry safflower oil and a concentration of very small (colloidal) birch bark extract powder particles. They act as an eco-friendly gelling agent as well as a preservative and antioxidant. The chemical compounds in the extracts accelerate the healing of skin wounds. Oleogel can be used as a raw material for cosmetic creams and nutritional supplements, as well as to reduce pigmentation spots on the skin.

Colloidal betulin hydrogel

The hydrogel is obtained from very small (colloidal) particles of birch bark extract powder dispersed uniformly in water or aqueous solution at a given concentration. This hydrogel can be used as an organic emulsifier, preservative and antioxidant in body cream emulsions, thus replacing several synthetic ingredients at the same time.

In the future, betulin may be able to replace many of the synthetic surfactants currently used in cosmetic products.

Filsuvez – the first betulin-based medicine

Although betulin is now widely used in folk medicine, homeopathic remedies and dietary supplements, its journey to the first modern, clinically approved medicines has not been a fast one. Medical research takes many years. ​

Filsuvez, a skin wound healing gel from Amryt Pharmaceuticals, an international biopharmaceutical company based in Ireland, was approved by the European Medicines Agency in June 2022 and by the US Food and Drug Administration in December 2023.

This is the first precedent for the international recognition of triterpene-based medicines, with others likely to follow in the near future.

​Herbal description of Filsuvez gel:

https://www.ema.europa.eu/lv/documents/product-information/filsuvez-epar-product-information_lv.pdf

Supports liver function

• Reduces fatty liver dystrophy
• Reduces the side effects of long-term use of medicines
• Helps faster recovery in complex hepatitis A, B, C therapy
• Promotes faster detoxification from toxic substances, alcohol, and drugs

For complex therapy of oncological diseases

• Inhibits the spread and invasion of different types of cancers
• Inhibits tumour cell growth by preventing the formation of new blood vessels in the tumour mass
• Increases the effectiveness of chemotherapy and reduces the incidence and severity of side effects

For the treatment of inflammations

• Reduces chronic and acute inflammation in the pharyngitis, tonsillitis, bronchitis and other types of inflammation

For exposure to viruses

• Inhibits the development of herpes, ECHO, adenovirus, cytomegalovirus infections

Reduces blood lipid levels

• Reduces triglycerides and cholesterol in the blood
• Inhibits the development of atherosclerosis, heart and cerebral circulatory disorders, hypertensive disease, chronic heart failure, memory impairment caused by atherosclerosis, circulatory disorders in the legs

When betulin is recommended

• Chronic inflammatory processes in the body
• Prolonged use of medication
• Frequent contact with toxic substances
• Acute viral infections
• Weakness of the immune system
• Alcoholism, acute hangover syndrome, drug intoxication
• In the case of antibiotic resistance

Betulin in food supplements

Artūrs Tereško is a well-known physician, phytotherapist, and head of the company ZS “Doctus”. Ambassador for betulin, who researches and develops its use in food supplements on a daily basis. Artūrs Tereško and his company “Doctus” work closely with the Latvian State Institute of Wood Chemistry in the development of betulin products.

For more information on the supplements developed, how to use them and where to buy them, see: www.fitoterapija.lv

Explore the Research: References to Studies Supporting the Exhibit

General

Jager S., Laslzcuk M. N., Scheffler A. A. preliminary pharmacokinetic study of betulin, the main pentacyclic triterpene from extract of outer bark of birch (Betulae alba cortex). Betulin as a Multitarget Compound.

S. Grīnberga, H. Cīrule, E. Sevostjanovs. Salīdzinošs pētījums par betulīna nanosuspensijas biopieejamību. Organiskās Sintēzes institūts. 17.01.2023.

Una Riekstiņa, Kaspars Jēkabsons, Karīna Goluba „Pētījums par augstas īpatnējās virsmas bērza tāss betulīna daliņu ietekmi uz cilvēka ādas šūnām”.

I. Hartmane, I. Mikažāns, V.Bondare-Ansberga, Kristīne Saliniece, Artūrs Tereško, pētījums “Augstas īpatnējās virsmas bērza tāss ekstraktu saturoša kosmētiskā produkta Betulogel spējas mazināt ādas pigmentāciju” 01.09. – 30.10. 2023.

Novel development method of oleogel as solution to improve bioavailability of birch bark extracts compared with other dispersed systems. Authors: Laura Andze, Sanita Vitolina, Rudolfs Berzins, Janis Rizhikovs, Daniela Godina, Arturs Teresko, Solveiga Grinberga, Eduards Sevostjanovs, Helena Cirule, Edgars Liepins, Aigars Paze

Evaluation of Oleogels Stabilized by Particles of Birch Outer Bark Extract Through a Novel Approach. Authors: Sanita Vitolina *, Rudolfs Berzins, Janis Rizhikovs, Daniela Godina, Arturs Teresko, Aigars Paze

Szlasa, W., Ślusarczyk, S., Nawrot-Hadzik, I. et al. Betulin and Its Derivatives Reduce Inflammation and COX-2 Activity in Macrophages. Inflammation 46, 573–583 (2023). https://doi.org/10.1007/s10753-022-01756-4

Clinical studies

Barret JP, Podmelle F, Lipový B, Rennekampff HO, Schumann H, Schwieger-Briel A, Zahn TR, Metelmann HR; BSH-12 and BSG-12 study groups. Accelerated re-epithelialization of partial-thickness skin wounds by a topical betulin gel: Results of a randomized phase III clinical trials program. Burns. 2017 Sep;43(6):1284-1294. doi: 10.1016/j.burns.2017.03.005. Epub 2017 Apr 8. PMID: 28400148.

Frew Q, Rennekampff HO, Dziewulski P, Moiemen N; BBW-11 Study Group; Zahn T, Hartmann B. Betulin wound gel accelerated healing of superficial partial thickness burns: Results of a randomized, intra-individually controlled, phase III trial with 12-months follow-up. Burns. 2019 Jun;45(4):876-890. doi: 10.1016/j.burns.2018.10.019. Epub 2018 Dec 14. PMID: 30559054.

Liver protection

Szuster-Ciesielska A., Kandefer-Szerszeń M. Protective effects of betulin and betulinic acid against ethanol-induced cytotoxicity in Hep G2 cells. 2005.

Szuster-Ciesielska, A.; Pilipów, K.; Kandefer-Szerszeń, M. Protective effect of betulin and betulinic acid on acetaminophen and ethanol-induced cytotoxicity and reactive oxygen species production in HepG2 cells. J. Pre-Clin. Clin. Res. 2010, 4, 96–100.

Bai T, Yang Y, Yao YL, Sun P, Lian LH, Wu YL, Nan JX. Betulin alleviated ethanol-induced alcoholic liver injury via SIRT1/AMPK signaling pathway. Pharmacol Res. 2016 Mar;105:1-12. doi: 10.1016/j.phrs.2015.12.022. Epub 2016 Jan 15. PMID: 26776965.

Buko V, Kuzmitskaya I, Kirko S, Belonovskaya E, Naruta E, Lukivskaya O, Shlyahtun A, Ilyich T, Zakreska A, Zavodnik I. Betulin attenuated liver damage by prevention of hepatic mitochondrial dysfunction in rats with alcoholic steatohepatitis. Physiol Int. 2019 Dec 1;106(4):323-334. doi: 10.1556/2060.106.2019.26. Epub 2019 Oct 17. PMID: 31619044.

Cholesterol reduction

Inhibition of SREBP by a small molecule, betulin, improves hyperlipidemia and insulin resistance and reduces atherosclerotic plaques. (Tang J., J. J., T.,Li J. G., Qi W., Qiu W.W., Li P. S., Li B. L., Song B. L.) Cell Metab. 2011.

Treatment of hepatitis

Alexander N., Shikova, B., Georgy I., Djachuka, Dmitry V., Sergeeva C., Pozharitskaya O. C N., Esaulenkoc Elena V., Kosmanb Valery ,Vera M., Makarov G. C Birch bark extract as therapy for chronic hepatitis C – A pilot study.

Strengthening immunity

Yamashita, K.; Lu, H.; Lu, J.; Chen, G.; Yokoyama, T.; Sagara, Y.; Manabe, M.; Kodama, H. Effect of three triterpenoids, lupeol, betulin, and betulinic acid on the stimulus-induced superoxide generation and tyrosyl phosphorylation of proteins in human neutrophils. Clin. Chim. Acta 2002, 325, 91–96. [Google Scholar] [CrossRef]

Antioxidant activity

Kruszniewska-Rajs, C.; Strzałka-Mrozik, B.; Kimsa-Dudek, M.; Synowiec-Wojtarowicz, A.; Chrobak, E.; Bębenek, E.; Boryczka, S.; Głuszek, S.; Gola, J.M. The Influence of Betulin and Its Derivatives EB5 and ECH147 on the Antioxidant Status of Human Renal Proximal Tubule Epithelial Cells. Int. J. Mol. Sci. 2022, 23, 2524. [Google Scholar] [CrossRef] [PubMed]

Effect of three triterpenoids, lupeol, betulin, and betulinic acid on the stimulus-induced superoxide generation and tyrosyl phosphorylation of proteins in human neutrophils. Yamashita K.., Lu H., Lu, Chen G., Yokoyama T., Sagara Y., Manabe M., Kodama H.

Anti-virus activity

Pavlova N. I ., Savinova O. V., Nikolaeva S. N., Boreko E. I., Flekhter O. B. Antiviral activity of betulin, betulinic and betulonic acids against some enveloped and non-enveloped viruses.

Antitumor activity

Schwiebs A., Radeke H. H. Immunopharmacological Activity of Betulin in Inflammation-associated Carcinogenesis.

Comprehensive Review on Betulin as a Potent Anticancer Agent Sylwia Katarzyna Król, 1 , * Michał Kiełbus, 1 Adolfo Rivero-Müller, 1 , 2 , 3 and Andrzej Stepulak National Institutes of Health 2015.

Wound healing

“From a traditional medicinal plant to a rational drug: understanding the clinically proven wound healing efficacy of birch bark extract”. Ebeling S, Naumann K, Pollok S2, Wardecki T, Vidal-Y-Sy S, Nascimento JM, Boerries M, Schmidt G, Brandner JM, Merfort I

For the treatment of necrotic herpes

Topical treatment of necrotising herpes zoster with betulin from birch bark. Weckesser S., Laszczyk MN, Müller ML, Schempp CM, Schumann H. 2010

Treatment of injuries

Armin Scheffler ”The Wound Healing Properties of Betulin from Birch Bark from Bench to Bedside”.

Anti-inflammatory effect

Lopez-Otin, C, Blasco M.A, Partridge L, Serrano M, Kroemer G. Hallmarks of aging: An expanding universe. Cell Volume 186, Issue 2, 19 January 2023, Pages 243-278, https://doi.org/10.1016/j.cell.2022.11.001

Oliveira-Costa JF, Meira CS, Neves MVGD, Dos Reis BPZC, Soares MBP. Anti-Inflammatory Activities of Betulinic Acid: A Review. Front Pharmacol. 2022 May 23;13:883857. doi: 10.3389/fphar.2022.883857. PMID: 35677426; PMCID: PMC9168372.

Ou, Z., Zhao, J., Zhu, L., Huang, L., Ma, Y., Ma, C., et al. (2019). Anti-inflammatory Effect and Potential Mechanism of Betulinic Acid on λ-carrageenan-induced Frontiers in Pharmacology | www.frontiersin.org 8 May 2022 | Volume 13 | Article 883857 Oliveira-Costa et al. Betulinic Acid as Anti-Inflammatory Agent Paw Edema in Mice. Biomed. Pharmacother. 118, 109347. doi:10.1016/j.biopha. 2019.109347

Oyebanji BO, Saba AB, Oridupa OA. Studies on the anti-inflammatory, analgesic and antipyrexic activities of betulinic acid derived from Tetracera potatoria. Afr J Tradit Complement Altern Med. 2013 Nov 2;11(1):30-3. PMID: 24653551; PMCID: PMC3957239.

Li, N., Gong, Z., Li, X., Ma, Q., Wu, M., Liu, D., et al. (2019). Betulinic Acid Inhibits the Migration and Invasion of Fibroblast-like Synoviocytes from Patients with Rheumatoid Arthritis. Int. Immunopharmacol. 67, 186–193. doi:10.1016/j. intimp.2018.11.042

Huimin, D., Hui, C., Guowei, S., Shouyun, X., Junyang, P., and Juncheng, W. (2019). Protective Effect of Betulinic Acid on Freund’s Complete AdjuvantInduced Arthritis in Rats. J. Biochem. Mol. Toxicol. 33, e22373. doi:10.1002/jbt. 22373

Yoganathan Kamaraj and others, Triterpenoid compound betulin attenuates allergic airway inflammation by modulating antioxidants, inflammatory cytokines and tissue transglutaminase in ovalbumin-induced asthma mice model, Journal of Pharmacy and Pharmacology, Volume 73, Issue 7, July 2021, Pages 968–978, https://doi.org/10.1093/jpp/rgab015

Antiatherosclerosis effect

Juan Zhang, Hesham S. Almoallim, Sulaiman Ali Alharbi, Baihui Yang, Anti-atherosclerotic activity of Betulinic acid loaded polyvinyl alcohol/methylacrylate grafted Lignin polymer in high fat diet induced atherosclerosis model rats, Arabian Journal of Chemistry,Volume 14, Issue 2, 2021, 102934, ISSN 1878-5352, https://doi.org/10.1016/j.arabjc.2020.102934

Jung Joo Yoon, Yun Jung Lee, Byung Hyuk Han, Eun Sik Choi, Min Chul Kho, Ji Hun Park, You Mee Ahn, Hye Yoom Kim, Dae Gill Kang, Ho Sub Lee, Protective effect of betulinic acid on early atherosclerosis in diabetic apolipoprotein-E gene knockout mice, European Journal of Pharmacology, Volume 796, 2017, Pages 224-232, ISSN 0014-2999, https://doi.org/10.1016/j.ejphar.2016.11.044.

Neuroprotection

Huang Y, Zhu Z, Luo C, Ma C, Zhu L, Kong L, Li R, Wu J, Yuan Z, Yi J. Betulinic acid attenuates cognitive dysfunction, oxidative stress, and inflammation in a model of T-2 toxin-induced brain damage. Environ Sci Pollut Res Int. 2022 Jul;29(34):52098-52110. doi: 10.1007/s11356-022-19498-z. Epub 2022 Mar 7. PMID: 35254615.

For lung health

Yue Q, Deng X, Li Y, Zhang Y. Effects of Betulinic Acid Derivative on Lung Inflammation in a Mouse Model of Chronic Obstructive Pulmonary Disease Induced by Particulate Matter 2.5. Med Sci Monit. 2021 Feb 12;27:e928954. doi: 10.12659/MSM.928954. PMID: 33612710; PMCID: PMC7885291.

For the treatment of psoriasis

Liu C, Chen Y, Lu C, Chen H, Deng J, Yan Y, Xu YY, Liu H, Huang H, Wei J, Han L, Dai Z. Betulinic acid suppresses Th17 response and ameliorates psoriasis-like murine skin inflammation. Int Immunopharmacol. 2019 Aug;73:343-352. doi: 10.1016/j.intimp.2019.05.030. Epub 2019 May 23. PMID: 31129421.

Studies on birch bark

Babitskaya, V.G., V.V. Shcherba, and N.V. Lkonnikova. 2000. Melanin complex of the fungus Inonotus obliquus. Applied Biochemistry and Microbiology 36: 377–381.

Chen, H., X. Lu, Z. Qu, Z. Wang, and L. Zhang. 2010. Glycosidase inhibitory activity and antioxidant properties of a polysaccharide from the mushroom Inonotus obliquus. Journal of Food Biochemistry. 34: 178–191.

Choi, S.Y., S.J. Hur, C.S. An, Y.H. Jeon, Y.J. Jeoung, J.P. Bak, and B.O. Lim. 2010. Anti-Inflammatory effects of Inonotus obliquus in colitis induced by dextran sodium sulfate. Journal of Biomedicine and Biotechnology 2010 (Article ID 943516): 1–5.

Chung, M.J., C.K. Chung, Y. Jeong, and S.S. Ham. 2010. Anticancer activity of subfractions containing pure compounds of Chaga mushroom (Inonotusobliquus) extract in human cancer cells and in Balbc/c mice bearing Sarcoma-180 cells.Nutrition Research and Practice.

Moghaddam, M.G., F.B.H. Ahmad, and A.Samzadeh-Kermani. 2012. Biological activity of betulinic ahttps://mapi.inbox.lv/mailbox/arturs_teresko%40inbox.lv/folders/INBOX%2Fdraft/messages/1432/inline?partid= a review. Pharmacology & Pharmacy 3: 119-123.

Giridhan, V.V., R.A. Thandavarayan, and T. Konishi. 2011. Amelioration of scopolamine induced cognitive dysfunction and oxidative stress by Inonotus obliquus – a medicinal mushroom. Food and Function 6: 320–327.

Hu, H., Z. Zhang, Z. Lei, Y. Yang, and N. Sugiura1. 2009. Comparative study of antioxidant activity and antiproliferative effect of hot water and ethanol extracts from the mushroom Inonotus obliquus. Journal of Bioscience and Bioengineering 107: 42–48.

Kahlos, K. 1996. Preliminary test of antiviral activity of two Inonotus obliquus strains. Fitoterapia 67: 344–347.

Kim, H.-G., D.-H. Yoon, C.-H. Kim, B. Shrestha, W.-C. Chang, S.-Y. Lim, W.-H. Lee, S.-G. Han, J.-O Lee, M.-H. Lim, G.-Y. Kim, S. Choi, W.O Song, J.-M. Sung, K.-C. Hwang, T.-W. Kim. 2007. Ethanol extract of Inonotus obliquus inhibits lipopolysaccharide-induced inflammation in RAW 264.7 macrophage cells. Journal of Medicinal Food 10: 80–89.

Inonotus obliquus Journal of the Korean Society for Applied Biological Chemistry 54: 287–294.

Lee, S.H., H.S. Hwang, and J.W. Yun. 2009. Antitumor activity of water extract of a

mushroom, Inonotus obliquus, against HT-29 human colon cancer cells. Phytotherapy Research, online publication by Wiley Interscience, DOI: 10.1002/ptr.

Lu, X., H. Chen, P. Dong, and X. Zhang. 2010. Phytochemical characteristics and hypoglycaemic activity of fraction from mushroom Inonotus obliquus. Journal of the Science of Food and Agriculture 90: 276–80.

Najafzadeh M, P.D. Reynolds, A. Baumgartner, D. Jerwood , and D. Anderson. 2007.

Chaga mushroom extract inhibits oxidative DNA damage in lymphocytes of patients with inflammatory bowel disease. Biofactors 31: 191–200.

Pavlova, N.I., O.V. Savinova, S.N. Nikolaeva, E.I. Boreko, and O.B. Flekhter. 2003. Antiviral activity of betulin, betulinic and betulonic acids against some enveloped and non-enveloped viruses. Fitoterapia 74: 489–492.

Rogers, R. 2011. The Fungal Pharmacy. North Atlantic Books, Berkeley, CA.

Shibnev, V.A., D.V. Mishin, T.M. Garaev, N.P. Finogenova, A.G. Botikov, and P.G. Deryabin. 2011. Antiviral activity of Inonotus obliquusfungus extract towards infection caused by hepatitis C virus in cell cultures. Bulletin of Expirmental Biology and Medicine 151: 612-614.

Spinosa, R. 2006. The chaga story. The Mycophile 47: 1, 8, 23.

Wasser, S.P. 2002. Medicinal mushrooms as a source of antitumor and immunomodulating polysaccharides. Applied Microbiology and Biotechnology 60: 258–274.

Youn, M.-J., J.-K. Kim, S.-Y. Park, Y. Kim, S.-J. Kim, J.S. Lee, K.Y. Chai, H.-J. Kim, M.-X. Cui, H.S. So, K.-Y. Kim, R. Park. 2008. Chaga mushroom (Inonotus obliquus) induces G0/G1arrest and apoptosis in human hepatoma HepG2 cells. World Journal of Gastroenterology 14: 511–517.

C. Park, E.S. Kim, K.I. Park, H.S. So, and R. Park. 2009. Potential anticancer properties of the water extract of Inonotus [corrected] obliquus by induction of apoptosis in melanoma B16-F10 cells. Journal of Ethnopharmacology 121: 221–228.