Absorption, Distribution and Excretion
In the small intestine, most triglycerides are split into monoglycerides, free fatty acids, and glycerol, which are absorbed by the intestinal mucosa. Within the epithelial cells, resynthesized triglycerides collect into globules along with cholesterol and phospholipids and are encased in a protein coat as chylomicrons . Chylomicrons are transported in the lymph to the thoracic duct and eventually to the venous system. The chylomicrons are removed from the blood as they pass through the capillaries of adipose tissue. Fat is stored in adipose cells until it is transported to other tissues as free fatty acids which are used for cellular energy or incorporated into cell membranes.
When 14C-labeled long-chain triglycerides are administered intravenously, 25% to 30% of the radiolabel is found in the liver within 30 to 60 minutes, with less than 5% remaining after 24 hours. Lesser amounts of radiolabel are found in the spleen and lungs. After 24 hours, nearly 50% of the radiolabel has been expired in carbon dioxide, with 1% of the carbon label remaining in the brown fat. The concentration of radioactivity in the epididymal fat is less than half that of the brown fat.
The absorption of [1- 14C]tristearin was evaluated using groups consisting of six to seven male Wistar rats (weights =200 to 250 g). The rats were prepared either with an external bile fistula or a sham operation (control group), and then allowed to recover for 6 to 12 hours. Weighed doses of [1- 14C]tristearin were fed in a pellet of bran. Doses of 25, 50, 100, and 200 mg were administered to four groups, respectively. The rats were killed after 16 hours and lipid from the stomach, small gut, and colon (with feces) was extracted. Absorption was expressed as the percentage of the dose that had left the stomach. Only rats in which 80% or more of the dose had left the stomach were used. Tristearin absorption was classified as poor at all administered doses. Significantly lower absorption of tristearin was noted only in the 200 mg dose group ( p <.02, n=6)
Feeding expt with (14)C-labelled tristearin indicated that ruminal bacteria actively hydrogenated, degraded, and synthesized fatty acids. Stearic acid seemed to be absorbed from small intestine at slower rate than other fatty acids.

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Metabolism / Metabolites
Hydrolysis of /Tristearin/ by hepatic triacylglycerol lipase in plasma from ICR mice has been demonstrated in vitro.

[1]. Molecular Insights into the Eutectic Tripalmitin/Tristearin Binary System. J Am Chem Soc. 2018 Oct 3;140(39):12405-12414.

Tristearoylglycerol is a triglyceride that is glycerol in which all three hydroxy groups have been formally esterified with stearic acid. It has a role as a plant metabolite and a Caenorhabditis elegans metabolite. It is functionally related to an octadecanoic acid.
Tristearin has been reported in Sciadopitys verticillata, Lysiphlebia japonica, and other organisms with data available.
TG(18:0/18:0/18:0) is a metabolite found in or produced by Saccharomyces cerevisiae.
See also: Hydrogenated cottonseed oil (annotation moved to).

C57H110O6

891.5

890.83

555-43-1

Tristearin-d105;125941-88-0;Tristearin-d40;33048-69-0;Tristearin-d5;55256-03-6;Tristearin-d9;285979-76-2

11146

White to off-white solid powder

0.9±0.1 g/cm3

813.0±32.0 °C at 760 mmHg

72-75 °C

299.4±25.2 °C

0.0±2.9 mmHg at 25°C

1.466

25.27

0

6

56

63

886

0

DCXXMTOCNZCJGO-UHFFFAOYSA-N

InChI=1S/C57H110O6/c1-4-7-10-13-16-19-22-25-28-31-34-37-40-43-46-49-55(58)61-52-54(63-57(60)51-48-45-42-39-36-33-30-27-24-21-18-15-12-9-6-3)53-62-56(59)50-47-44-41-38-35-32-29-26-23-20-17-14-11-8-5-2/h54H,4-53H2,1-3H3

2,3-di(octadecanoyloxy)propyl octadecanoate

Glyceryl tristearate; Stearin; Tristearin

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Ethanol : ~10 mg/mL (~11.22 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)