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  • Chemical Name:L-Tryptophan
  • CAS No.:73-22-3
  • MF:C11H12N2O2
  • MW:204.23
  • Purity:>98% or As customer requested
  • Color:White to yellow-white
  • Product Categories: Biochemistry;Nutritional Supplements;L-Amino Acids;Amino Acids; APIs; Biochemical Engineering
  • Test method: HPLC


What is Tryptophan?

Tryptophan is the least plentiful of all 22 amino acids and an essential amino acid in humans (provided by food), Tryptophan is found in most proteins and a precursor of serotonin. Tryptophan is converted to 5-hydroxy-tryptophan (5-HTP), converted in turn to serotonin, a neurotransmitter essential in regulating appetite, sleep, mood, and pain. Tryptophan bulk is a natural sedative and present in dairy products, meats, brown rice, fish, and soybeans.

Basic information   

Product Name: L-Tryptophan
Synonyms: Tryptophan; L-Tryptophane; Tryptophane; Tryptacin; L-Tryptophan(pharm grade); Pacitron; L-Tryptofan
CAS: 73-22-3
MF: C11H12N2O2
MW: 204.23
EINECS: 200-795-6
Product Categories: Biochemistry;Nutritional Supplements;L-Amino Acids;Amino Acids; APIs; Biochemical Engineering
Chemical Structure


Chemical Properties   

Melting point  289-290 °C (dec.)(lit.)
alpha  -31.1 º (c=1, H20)
Boiling point  342.72°C (rough estimate)
density  1.34
refractive index  -32 ° (C=1, H2O)
storage temp.  2-8°C
solubility  20% NH3: 0.1 g/mL at 20 °C, clear, colorless
pka 2.46(at 25℃)
form  powder
color  White to yellow-white
PH 5.5-7.0 (10g/l, H2O, 20℃)
optical activity [α]20/D 31.5±1°, c = 1% in H2O
Water Solubility  11.4 g/L (25 ºC)
Merck  14,9797
BRN  86197
Stability: Stable. Incompatible with strong acids, strong oxidizing agents.
Usage And Synthesis

Tryptophan Benefits       

1. Helps Improve Sleep Quality

There’s evidence that tryptophan has natural sedative effects that can help you sleep better, and as a result it can help improve overall health. A lack of sleep is a risk factor for problems like depression, decline in motor coordination, reduced concentration and memory, muscle aches, weight gain, and more. Tryptophan offers a natural remedy for getting better sleep and reducing problems associated with sleep apnea or insomnia, all without the need for sleep-inducing prescriptions that can cause many unwanted side effects. (3)

The strongest benefits for treating sleep disorders with tryptophan bulk have been found when using supplements, rather than just food sources of tryptophan alone. Supplements have been found to help decrease the amount of time it takes to fall asleep, improve mood the day next following better sleep quality, decrease teeth grinding during sleep (called bruxism) and decrease sleep apnea episodes during sleep (periodically stopping breathing throughout the night).

2. Lifts Your Mood and Reduces Depression and Anxiety

Not only can tryptophan help you sleep more soundly, but it’s also been shown to be a natural mood lifter and offer protection against depression, anxiety and the numerous negative symptoms associated with high stress levels (like irritable bowel syndrome and heart disease, for example). Many studies have found that L-tryptophan converts to calming serotonin in the brain and helps make other essential amino acids more available, which in turn helps control someone’s moods and turn down production of stress hormones.

Some studies have even shown that tryptophan bulk and 5HTP supplementation can work as well as prescription antidepressants. Preliminary studies indicate that 5HTP is beneficial for treating people with mild to moderate depression just as well as medications like fluvoxamine (Luvox). Among 63 participants in one study, 5HTP did just as well as those who received Luvox for lowering depressive symptoms. (4)

Some research has shown that reduced intakes of tryptophan can cause significant reductions in certain brain activities that promote happiness and that low serotonin levels are more common among people with anxiety and depression. Study results show that patients are often successful at lowering negative symptoms related to mood disorders, addictions or hormonal problems like PMS/PMDD (premenstrual dysphoric disorder) when taking six grams of L-tryptophan per day. This amount taken for several months has been shown to decrease mood swings, restlessness, tension and irritability. (5)

3. Can Help with Recovery from Addictions

Supplementing with a combination of calming, anxiety-reducing amino acids and herbs — such as L-tryptophan, St. John’s wort and 5HTP — has been shown to help people overcome addictions by increasing serotonin and melatonin production. L-tryptophan is often given to people trying to quit smoking in order to improve the effectiveness of conventional treatment programs that teach people to control impulses and their emotional states better. (6)

4. Reduces Headaches and Migraines

Studies have found that tryptophan bulk depletion worsens pain associated with tension headaches and migraines, plus can cause aggravated nausea and sleep problems experienced by many migraine sufferers. Increased brain synthesis of serotonin seems to offer natural relief for headaches and migraine symptoms, including sensitivity to light, indigestion, pain and more.

One study conducted by the Murdoch University School of Psychology in Australia found that five to eight hours after consuming a drink with a complete array of 19 different amino acids, including tryptophan, symptoms of migraines were significantly reduced. (7)

5. Can Help You Maintain a Healthy Weight

Tryptophan supplements can be used to help someone stick to a healthy diet and work toward the goal of losing weight. Increased serotonin levels promote calmness, clarity of mind, control over cravings or impulses, and even better metabolic functioning, which all boost weight loss.

Technical Support & Resources

Information provided in the product description is from published literature. Due to the nature of scientific experimentation, your results (e.g., selectivity and effective concentrations) or specific application for this product may differ. If you have questions about how this product fits your application, please contact our technical support staff.

MSDS: MSDS available.

COA: COA can be available if you send us inquiry.

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Packaging and Shipping




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