Dendroxine

Dendroxine: A Comprehensive Reference

1. Identity and Botanical/Chemical Description

Dendroxine is a naturally occurring alkaloid compound identified by its molecular formula C₁₇H₂₅NO₃ and recorded in chemical databases under PubChem Compound ID 101286284. Dendroxine has the molecular formula C₁₇H₂₅NO₃ and is catalogued with physical, chemical, and biological activity data. Dendroxine contains three oxygen atoms and has a molecular weight of approximately 291.39 grams per mole.

Nobilonine and dendroxine represent more highly oxygenated derivatives within the dendrobane alkaloid family. Both compounds maintain the characteristic tetracyclic framework but incorporate additional hydroxyl functionalities that distinguish them from the parent dendrobane structure.

Dendroxine belongs to the class of sesquiterpene alkaloids based on the picrotoxane skeleton. The stems and pseudo-bulbs of Dendrobium nobile contain the alkaloids dendrobine, 3-hydroxy-2-oxodendrobine, dendroxine, dendramine (= 6-oxydendrobine), and 6-oxydendroxine. Biochemically, all are pseudo-alkaloids: the carbon skeleton of the molecule is derived from a sesquiterpene instead of an amino acid.

Dendroxine was first characterized structurally in a landmark 1966 publication. Okamoto et al. published "The Structure of Dendroxine. The Third Alkaloid from Dendrobium nobile" in Chemical & Pharmaceutical Bulletin, vol. 14, no. 6, 1966, pp. 672–675. This study, conducted at the Faculty of Pharmaceutical Sciences, University of Tokyo, established dendroxine as the third distinct alkaloid isolated from Dendrobium nobile, after dendrobine and dendramine.

A concise enantioselective total synthesis of three sesquiterpenoid alkaloids—(−)-dendrobine, (−)-mubironine B, and (−)-dendroxine—has been achieved, utilizing enantioselective Diels–Alder chemistry. This work, published in Organic Letters (2018), confirmed the stereochemical identity of the natural compound and demonstrated the chemical complexity of the picrotoxane skeleton shared by all three alkaloids.

1.1 Natural Source: Dendrobium nobile and Related Species

Dendroxine is found exclusively within the genus Dendrobium, a large genus of orchids in the family Orchidaceae. Dendrobium is a genus of flowering plants belonging to the Orchidaceae family with more than 1,400 species, and many Dendrobium species have been used as medicinal plants in several Asian countries for thousands of years.

The primary source species is Dendrobium nobile Lindl. Dendrobium nobile Lindl. (DNL) is one of the main sources of traditional Chinese medicine, Shihu (Dendrobii caulis). Dendrobium nobile Lindl. is registered in the Chinese Pharmacopoeia as a traditional medicine.

Dendroxine co-occurs in D. nobile alongside a suite of related alkaloids. Alkaloids extracted and isolated from the dried stems of Dendrobium contain mainly dendrobine, dendrobine-N-oxide, nobilonine, dendroxine, 6-hydroxy-nobilonine, 13-hydroxy-14-oxodendrobine, mubironine, 6-hydroxynobiline, and dendramine. Additional hydroxylated derivatives of dendroxine itself—namely 6-hydroxydendroxine and 4-hydroxydendroxine—have also been identified in D. nobile extracts. Dendrobium nobile powder extract contains alkaloids at approximately 0.3% total content, including dendrobine, nobilonine, dendramine, dendroxine, 6-hydroxydendroxine, 4-hydroxydendroxine, nobilmethylene, and others.

The geographical range of D. nobile spans much of tropical and subtropical Asia. Dendrobium nobile, an enduring epiphytic herb belonging to the Orchidaceae family, is primarily found in regions south of the Yangtze River, encompassing Guizhou, Yunnan, Guangxi, and other subtropical areas of China. The plant is also found in India, Nepal, Thailand, Vietnam, Laos, and other parts of Southeast and South Asia.

The stem (caulis) is the primary harvested part. Generally, the fibrous stems of Dendrobium are employed as the officinal parts in ethnopharmacology, preserved by dry processing. In practice, the stems of 3-year-old D. nobile are usually used as the main source of Dendrobii Caulis. Dozens of alkaloids with different structures have been separated and extracted from Dendrobium, mainly enriched in the rhizome of Dendrobium. The content of alkaloids is not only related to the species of Dendrobium, but also to the growth age and distribution parts of the plants.

1.2 Common Forms and Preparations

Dendroxine as an isolated, purified compound is primarily a research chemical and is not sold individually as a dietary supplement. In the supplement industry, it is encountered as a constituent of Dendrobium nobile stem extracts standardized for alkaloid content. The label of a commercial supplement product described its dendrobium extract as "concentrated for alkaloid content including Dendrobine, Dendroxine, Dendramine, B-Phenylethylamine, N,N-Dimethyl-B-Phenylethylamine, and N,N-Diethyl-B-Phenylethylamine."

Traditional preparations of the source plant include dried stems for decoctions and teas. A tea made from the stems of Dendrobium species is taken for complaints such as fever, sunstroke, and excessive perspiration. The stems are usually used either alone or mixed with other tonic Chinese herbs, such as American ginseng and Barbary wolfberry fruit. Modern supplement forms include standardized powdered extracts, capsules, and pre-workout powder blends.

2. Traditional and Historical Use

The medicinal use of Dendrobium nobile—the principal botanical source of dendroxine—has a documented history spanning approximately 1,500 years in Chinese medicine. The history of the utilization of medicinal Dendrobium is one of 1,500 years in China, and the first record of its use was found in the Shen Nong Ben Cao Jing (Shennong's Classic of Materia Medica). As described in "Shennong Herbal Medicine" as early as 2000 years ago, the most notable health benefits of Dendrobium have been shown to include therapeutic effects such as "nourishing yin," "promoting the production of body fluids," "clearing heat," and "supplementing stomach."

Dendrobium, together with Dong Chong Xiao Cao (Cordyceps sinensis), Ren Shen (Radix Ginseng), and Ling Zhi (Ganoderma lucidum), has been regarded as one of the precious and top-grade traditional Chinese medicines (TCM) in China for thousands of years.

The Compendium of Materia Medica (also known as Bencao Gangmu), a Chinese herbology volume written by Li Shizhen during the Ming dynasty, also recorded that Dendrobium has the effect of removing arthralgia, lowering "qi," strengthening yin, and nourishing essence.

Dendrobium is widely used as a traditional medicine for nourishing yin, clearing heat, relieving coughs, brightening eyes, strengthening body constitution, and promoting longevity. Dendrobium has been used in traditional Chinese medicine for many centuries to treat thirst, fever, diabetes, infection, inflammation, cancer, protect eyesight, and improve appetite and digestion.

Among the Dendrobium species, Dendrobium nobile Lindl. is one of the 50 fundamental herbs used in traditional Chinese medicine (TCM). It is associated with the Stomach, Kidney, and Lung meridians in TCM theory. It is well known as a Lung, Stomach, and Kidney Yin tonifying herb.

The ethnobotanical use of Dendrobium extends beyond China. Many Dendrobium species have been used as medicinal plants in several Asian countries for thousands of years. In Thailand, the flowers are deep-fried and eaten as snacks; in Nepal, the flowers are pickled.

In the context of traditional systems, the properties attributed to dendroxine-containing plant preparations were not attributed to any single alkaloid constituent, but to the whole plant or its extracts. Dendroxine itself was not isolated and chemically characterized until 1966, meaning all traditional use refers to the whole-plant material and its alkaloid-containing preparations.

3. Key Constituents, Chemical Context, and Active Compounds

To understand dendroxine's place in the pharmacological landscape, it is essential to situate it within the broader phytochemical profile of D. nobile.

3.1 Alkaloid Class

Alkaloids are the first compounds isolated and purified from Dendrobium and are also important active components of the plant. Alkaloids have a wide range of pharmacological activities including antioxidant, anti-anxiety, anti-inflammatory, and antidepressant properties, as well as neuroprotective effects.

The stems of D. nobile contain alkaloids, polysaccharides, sesquiterpenes, phenanthrenes, benzenes, and other chemical components. Among them, alkaloids and polysaccharides have been regarded as the main active constituents, with dendrobine as the characteristic component. As many as 213 compounds have been isolated from D. nobile, and 101 compounds have been identified from its flowers via gas chromatography-mass spectrometry (GC–MS).

The principal alkaloid of D. nobile is dendrobine. Dendrobine makes up 92.6% of the total alkaloid fraction (DNLA) of Dendrobium nobile. Dendroxine is quantitatively a minor constituent compared to dendrobine but is structurally closely related. The main alkaloids found in the stem of D. nobile are dendrobine, dendroxine, dendramine, dendrine, dendrobine N-oxide, nobilonine, dendrochrysine, and moscatiline. These alkaloids are primarily responsible for the analgesic, anti-inflammatory, and antipyretic effects.

3.2 Structural Classification of Dendroxine

Dendroxine belongs to the picrotoxane-type sesquiterpene alkaloid class. The picrotoxane-type sesquiterpenes, including dendrobine and its analogs, are characterized by a highly oxidized cis-hydrindene core with lactone rings and various oxidation states. Picrotoxane sesquiterpenoids are a special category of natural products characterized by a picrotoxane skeleton with a highly oxidised cis-hydrindene core, lactone rings, and epoxide functionalities. Since the first picrotoxane was isolated from Menispermum cocculus in the early 19th century, these compounds have attracted attention for their particular structures and powerful biological activities.

The structural identity of dendroxine as the "third alkaloid" of D. nobile was established by Okamoto and colleagues in 1966 at the University of Tokyo, published in the Chemical & Pharmaceutical Bulletin (PubMed PMID: 5964635). A 2018 total synthesis study published in Organic Letters confirmed the absolute configuration of (−)-dendroxine through enantioselective catalytic methods.

3.3 Relationship to Dendrobine (the Primary Active Alkaloid)

Scientific literature on the pharmacology of D. nobile alkaloids typically investigates the total alkaloid fraction (DNLA) or the primary alkaloid dendrobine specifically. The pharmacological activity attributed individually to dendroxine in the peer-reviewed literature is limited; most biological activity studies use the total alkaloid extract or dendrobine as the representative agent. Extracts from dendrobium contain the chemicals dendrobine, dendroxine, dendramine, and several others. Of these, dendrobine has pharmacologic effects that include analgesic (pain-killing) and anti-fever effects.

The 2023 PubMed study by Zunyi Medical University identified two new structural analogs—dendroxine B and denrine B—from ethanol extracts of D. nobile stems, alongside the known compound dendrobine. Phytochemical investigation of the ethanol extract of D. nobile stems yielded three alkaloid compounds, including two new compounds dendroxine B (2) and denrine B (3) as well as one known compound dendrobine (1). The structures of these compounds were identified using spectroscopic analyses. Compounds 1–3 were found to show protective effects against amyloid-β 1-42 (Aβ1-42)-induced neurotoxicity in rat pheochromocytoma (PC12) cells. This is the most specific direct pharmacological study linking dendroxine-type alkaloids to neuroprotection; however, the study focused primarily on dendrobine as the most potent agent.

4. Mechanisms of Action (Total Alkaloid Fraction and Dendrobine as Context)

Because dendroxine has not been studied extensively in isolation at the mechanism level, the following section describes the established mechanisms of the total alkaloid fraction (DNLA) and the closely related compound dendrobine, which constitutes the preponderance of the alkaloid fraction and shares the same picrotoxane scaffold.

4.1 Neurological Mechanisms

Dendrobine is a strongly selective competitive antagonist of β-alanine, taurine, and glycine. The chemical framework of dendrobine is closely related to picrotoxinin, giving it ability to block the glycinergic receptor at the picrotoxin binding site. In the spinal cord, the Renshaw cells secrete glycine, which stimulates glycinergic receptors, resulting in inhibition of motoneurons. This mechanism is shared across the dendrobane-type alkaloids due to common structural features of the picrotoxane skeleton.

In preclinical models of neurodegeneration, the total alkaloid fraction of D. nobile (DNLA) has shown neuroprotective activity. Studies have shown that the total alkaloids in Dendrobium regulate hepatic lipids and gluconeogenesis, reduce high blood pressure, and exhibit effects on the nervous system, as well as anti-inflammatory, anti-diabetic, anti-tumor, and anti-viral properties. Dendrobium alkaloids play a prominent role in neuroprotection.

4.2 Hepatic Metabolic Mechanisms

Previous studies have shown that Dendrobium alkaloids extracted from the stems of Dendrobium have beneficial effects on gene expression of glucose and lipid metabolism in the liver, and enhance gene expression of the Nrf2-antioxidant pathway, and increase the expression levels of peroxisome proliferator-activated receptor-α and glucose transporter-4 in the liver or adipose tissues, which may play a comprehensive role in the regulation of metabolic disorders.

Studies also showed that Dendrobium alkaloids could improve lipid metabolism of C57BL/6 mice with hepatic lipid accumulation via enhancing highly hydrophilic taurine-conjugated bile acids and decreasing the CA/CDCA ratio; the specific mechanism of liver protection of Dendrobium alkaloids was related to the promotion of cholesterol excretion.

4.3 Anti-tumor Mechanisms

The representative alkaloid in the Dendrobium genus is dendrobine, which is based on the picrotoxane skeleton and has been found to exert inhibitory effects on various tumors. The primary anti-tumor mechanism of dendrobine involves inhibiting the activation of proto-oncogenes and increasing the expression of oncogenes, thus suppressing the abnormal proliferation and differentiation of cells.

Dendrobine, by targeting JNK stress signaling, enhances cisplatin toxicity in vivo during chemotherapy for non-small cell lung cancer cells.

5. Scientific Evidence by Area of Use

Important caveat: The great majority of available scientific studies on this alkaloid family concern the total alkaloid fraction (DNLA) or the isolated compound dendrobine, rather than dendroxine itself. Wherever the evidence base relates specifically to dendroxine, that is noted. In all other cases, the evidence applies to the broader alkaloid context of the source plant. No human clinical trials have specifically investigated dendroxine as an isolated compound.

5.1 Neuroprotection and Cognitive Function

Evidence level: Preclinical (animal and cell-based); no human clinical trials for dendroxine specifically.

Phytochemical investigation of D. nobile stems yielded three alkaloid compounds—including the new compound dendroxine B (2) and one known compound dendrobine (1). Compounds 1–3 were found to show protective effects against amyloid-β 1-42 (Aβ1-42)-induced neurotoxicity in rat pheochromocytoma (PC12) cells. This is a cell-based assay only; results cannot be extrapolated to human therapeutic effects without further investigation.

Dendrobium sesquiterpenes (DSS) exhibit diverse pharmacological activities, especially sesquiterpene alkaloids and sesquiterpene glycosides. D. nobile, whose pharmacological activities have been studied by focusing on total alkaloids extracted from D. nobile (DNLA) and its representative compound dendrobine, has shown significant effects in blood glucose regulation, neuroprotection, and anti-tumor activity.

5.2 Metabolic Associated Fatty Liver Disease (MASLD)

Evidence level: One small open-label human trial; preliminary only.

In an open-label, single-arm, non-randomized, exploratory clinical study conducted from May 2020 to May 2021, 33 patients meeting the diagnostic criteria for MASLD were enrolled from the outpatient clinic of Longhua Hospital, affiliated with Shanghai University of Traditional Chinese Medicine. The primary objective was to evaluate the safety and clinical efficacy of Dendrobium nobile in the treatment of MASLD. The study was registered with the Chinese Clinical Trial Registry (ChiCTR2000034550). The study demonstrated significant improvement in liver function among MASLD patients treated with Dendrobium nobile. Network pharmacology identified key targets including PPARG, IL6, TNF, IL1B, and AKT1, with molecular docking confirming their interactions. The study's open-label, single-arm, non-randomized design represents a significant methodological limitation; these results are considered preliminary and require confirmation in randomized controlled trials.

5.3 Anti-tumor Activity

Evidence level: Preclinical (cell lines and animal models); no human clinical trials.

Experimental research on Dendrobium nobile Lindl. is focused primarily on oncologic, nervous system, cardiovascular, ophthalmic, and gastrointestinal diseases. D. nobile has a marked inhibitory effect on a variety of tumor cells.

Dendrobine, the primary alkaloid in the same chemical class as dendroxine, decreases viability of A549 non-small cell lung cancer cells at concentrations ranging from 2.5 to 15 µg/ml, induces apoptosis at 1 to 10 µg/ml, and reduces tumor growth in an A549 mouse xenograft model at 50 mg/kg per day. These are preclinical in vitro and animal results only.

5.4 Antidiabetic / Hypoglycemic Effects

Evidence level: Animal studies; one network pharmacology/clinical pilot study on the source plant.

D. nobile alkaloids have been used in traditional Chinese medicines to treat senile nervous system diseases such as obesity, hyperglycemia, and hyperlipidemia, with some clinical trial support. As a traditional Chinese medicine, Dendrobium is widely used in diabetes and neurodegenerative diseases related to aging.

DNLA has significant therapeutic effects on diabetes in animal studies. In D. nobile, most of the metabolites were identified as alkaloids and sesquiterpene glycosides. Alkaloids, represented by dendrobine, were enriched in D. nobile from year 1. D. nobile cultivated at year 1 was more recommended for hyperglycemic syndrome treatment; alkaloids were recommended to be used as markers to control quality for hyperglycemic syndrome treatment. These results are from animal and metabolomic studies, not human clinical trials.

5.5 Hepatoprotective Effects

Evidence level: Animal and cell-based studies.

Recent studies have shown that Dendrobium alkaloids play a role in protecting the liver. Despite the impressive pharmacological effects of Dendrobium extract, its poor bioavailability remains a challenging issue which limits its application. Accumulating data demonstrate that Dendrobium displays beneficial effects on liver injuries, which has potential for the prevention and treatment of hepatotoxicity and liver disorders.

5.6 Athletic Performance (Pre-workout Supplement Context)

Evidence level: No credible clinical evidence.

Dendrobium is now an ingredient in some pre-workout dietary supplements marketed to enhance physical or athletic performance. However, little evidence indicates that dendrobium is effective for this purpose. The U.S. Department of Defense's Operation Supplement Safety (OPSS) program has specifically reviewed this application and reached the same conclusion. No controlled human trials have established efficacy of dendroxine or total Dendrobium alkaloids for athletic performance enhancement.

6. Body Systems and Health Areas Associated with Dendroxine-Containing Preparations

Based on the body of peer-reviewed preclinical and limited clinical research, the following body systems have been subjects of investigation in association with D. nobile alkaloids (of which dendroxine is a constituent):

• Nervous system: The pharmacological effects of alkaloids include neuroprotective effects and regulatory effects on glucose and lipid metabolism.
• Hepatic/metabolic system: The alkaloids of Dendrobium nobile Lindl. (DNLA) are considered to have beneficial effects on liver metabolism, hepatic lipid homeostasis, neuronal activity, and resistance effects on tumors, cancers, and virus based on previous studies.
• Immune/inflammatory system: The pharmacological profile of D. nobile has been investigated in various domains. Notably, its strong antioxidant activity and ability to scavenge free radicals have been shown to support its immune-modulating, anti-inflammatory, and neuroprotective effects.
• Gastrointestinal system: In traditional Chinese medicine, it has been demonstrated that Dendrobium officinale can promote glandular secretion and protect the digestive tract, lungs, kidney, and eyes.
• Endocrine/blood glucose regulation: Addressed in the antidiabetic section above.
• Musculoskeletal system: Dendrobine, as a primary bioactive alkaloid isolated from Dendrobium nobile Lindl., has potential efficacy on osteoporosis due to the traditional use of Dendrobium nobile Lindl. in musculoskeletal disease.

7. Dosage Forms and Reported Dosages

No specific dosage recommendations for isolated dendroxine exist in the peer-reviewed clinical literature. Dendroxine is encountered in practice only as a constituent of total Dendrobium alkaloid extracts or whole-plant preparations. The following dosages reflect what has been reported in published scientific studies involving the source plant or its total alkaloid fraction:

• The pharmacological effects of dendrobine on animals were documented in 1935 by Chen and Chen. Dendrobine exhibited a weak analgesic effect when administered to mice at 5–15 mg/kg, and an antipyretic effect when administered to rabbits at 8.5 mg/kg.
• In a mouse model of postoperative cognitive dysfunction, dendrobine was administered at 10 or 20 mg/kg, with cognitive outcomes evaluated by Morris Water Maze and Novel Object Recognition tests.
• In an A549 non-small cell lung cancer mouse xenograft model, dendrobine at 50 mg/kg per day reduced tumor growth.
• In a subchronic safety assessment study in SD rats, Dendrobium extract was given by gavage at 800, 1600, or 2400 mg/kg daily; the no-observed-adverse-effect level was found to be greater than 2400 mg/kg.
• In the human clinical pilot study of MASLD, 33 patients were enrolled in an open-label, single-arm, non-randomized, exploratory clinical study using Dendrobium nobile preparations; specific daily dosages were not extractable from publicly available summaries of that record.

There are no established human dosages for dendroxine as an isolated compound. Despite the pharmacological effects reported for Dendrobium extract, poor bioavailability remains a challenging issue which limits its application; novel carriers such as liposomes, microspheres, nanoparticles, and transferosomes are being studied to improve bioavailability.

8. Safety Considerations and Known Interactions

8.1 Toxicity Profile of the Source Alkaloids

Dendrobium nobile herb is of very low toxicity and clinically tends to be considered non-toxic at regular dosage. However, overdose may cause convulsions, which can be relieved by sodium amytal. Clinically, allergic dermatitis has been reported.

The primary alkaloid of the same chemical class, dendrobine, has well-characterized toxicity at higher doses. Hypotensive effects were reported in experiments with frogs, cats, and a dog. The minimum lethal doses by intravenous injection are 20 mg/kg for mice and rats, 22 mg/kg in guinea pigs, and 17 mg/kg in rabbits. As a purified compound, dendrobine was found to produce progressive paralysis of peristaltic movement; it seems to act directly on muscles and also causes violent uterine contractions. For white mice, the lethal dose is 20 mg/kg, with effects being very rapid and resulting in convulsions and paralysis.

In addition to the effects mentioned above, dendrobine taken in sufficient amounts can slow breathing and heart rate and cause an unsafe drop in blood pressure. If Dendrobium nobile is part of a proprietary blend, there is no way to assess the exact dose present.

8.2 Metabolic Considerations

Dendrobine is the main sesquiterpene alkaloid of Dendrobium nobile Lindl. and exhibits potent neuroprotective activity. In rat and human liver microsomal studies, the elimination of dendrobine was very rapid (the in vitro elimination t_1/2 in rat and human liver microsomes was 1.35 and 5.61 minutes, respectively). After oral administration of dendrobine at 50 mg/kg in rats, low systemic exposure was observed (AUC_0-∞ = 629.2 ± 56.4 ng·h/mL). This rapid hepatic clearance has direct implications for bioavailability and pharmacological activity of the alkaloid fraction, including dendroxine-type compounds with closely related structures.

8.3 Seizure Risk

Because dendrobane alkaloids including dendrobine act as glycinergic receptor antagonists with structural similarity to picrotoxinin, there is a pharmacologically plausible concern regarding seizure risk at high doses. Overdose of Dendrobium nobile herb may cause convulsions, which can be relieved by sodium amytal.

8.4 Adulteration Concerns in Commercial Supplements

A major safety concern specific to the supplement context is adulteration. There have been some claims that dendrobium extracts can contain phenylethylamines (PEAs), a type of stimulant that can have effects similar to those of amphetamines. So far, however, no reliable evidence indicates that PEAs occur naturally in any dendrobium species, which suggests some dendrobium-containing products may have been "spiked."

A methamphetamine analog, N,α-diethyl-phenylethylamine (N,α-DEPEA), was identified in a mainstream dietary supplement. Several athletes have been disqualified from competition after testing positive for this banned stimulant. Three samples from different lot numbers of the supplement Craze were analyzed; two labs independently identified N,α-DEPEA in the supplement using UHPLC coupled to mass spectrometry.

At least one popular dendrobium-containing supplement (Craze, Driven Sports) has been identified by the U.S. Food and Drug Administration (FDA) as being adulterated with a stimulant drug.

8.5 Regulatory Status

According to the American Herbal Products Association (AHPA) composite list of old dietary ingredients (ODIs), both Dendrobium nobile Lindl. and Dendrobium officinale are old dietary ingredients. This designation pertains to the whole botanical, not to dendroxine as an isolated chemical entity.

Dendrobium nobile Lindl. was listed as the original species of medicinal dendrobium in the 2010 edition of the Chinese Pharmacopoeia.

8.6 Conservation Status

Due to the destruction of wild environments and increasing market demand, wild D. nobile (listed on the National Key Protected Wild Medicinal Plants) is being increasingly depleted. This conservation concern means that the majority of commercially available D. nobile extract is sourced from cultivated plants rather than wild harvest.

9. Summary of Evidence Limitations

The evidence base for dendroxine as a specific bioactive compound is highly limited. Most published pharmacological research uses the total alkaloid fraction of D. nobile (DNLA) or the isolated primary alkaloid dendrobine, not dendroxine in isolation. The 2023 PubMed study (PMID: 36658700) that characterizes dendroxine B represents among the most specific direct data available for any dendroxine-type compound, and it is a cell-based (in vitro) study.

More than sixty alkaloids have been isolated and identified from the Dendrobium genus. The pharmacological effects of Dendrobium alkaloids as hepatic lipid and gluconeogenesis regulation, as neuroprotection, and as anti-tumor, anti-inflammatory, anti-diabetes, and anti-virus factors have been described. However, attribution of specific activities to dendroxine specifically, as opposed to dendrobine or the mixture, remains an open scientific question. Human clinical data on D. nobile alkaloid preparations are sparse and methodologically weak (small sample sizes, open-label designs, lack of placebo controls).

References

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