Pinolenic Acid Ethyl Ester: Properties, Uses & Lab Guide

Pinolenic Acid ethyl ester is a polyunsaturated fatty acid ester derived from pinolenic acid, the characteristic omega-6 fatty acid of pine nut oil, and is used as a research tool in lipid metabolism, appetite regulation, and nutritional biochemistry studies.

Chemical Class

Polyunsaturated fatty acid ethyl ester (PUFA ester)

Parent Fatty Acid

Pinolenic acid (all-cis-5,9,12-octadecatrienoic acid, 18:3 Δ5,9,12)

SKU

P1074224

Recommended Storage

Store under inert atmosphere, protected from light, at low temperature (−20 °C recommended); avoid repeated freeze-thaw cycles

Solubility

Soluble in organic solvents such as ethanol, DMSO, and chloroform; essentially insoluble in water

Primary Research Areas

Lipid metabolism, appetite and satiety signalling, nutritional biochemistry, adipocyte biology

Chemical Identity and Structure

Pinolenic Acid ethyl ester is the ethyl ester of pinolenic acid, a rare all-cis C18 polyunsaturated fatty acid with three double bonds at positions Δ5, Δ9, and Δ12 (systematic name: ethyl all-cis-5,9,12-octadecatrienoate). Pinolenic acid is the most abundant and characteristic fatty acid found in the seed oil of Korean pine (Pinus koraiensis) and related pine species, typically comprising 15–20% of the total fatty acid content of pine nut oil.

The ethyl ester form offers improved chemical stability and handling convenience compared with the free acid, making it well-suited for in vitro biological assays and formulation studies. The compound belongs to the non-methylene-interrupted (NMI) fatty acid family, a structural class distinct from the conventional n-3 and n-6 series, which contributes to its unique biological profile.

Biological Activities and Research Applications

Pinolenic acid and its derivatives have attracted significant scientific interest for their effects on appetite regulation and lipid metabolism. Key reported activities that make Pinolenic Acid ethyl ester a valuable research tool include:

• Appetite and satiety modulation: Pinolenic acid has been reported to stimulate the release of cholecystokinin (CCK) and glucagon-like peptide-1 (GLP-1), gut hormones involved in satiety signalling. Researchers studying appetite-regulatory mechanisms may use the ethyl ester form in cell-based or ex vivo intestinal models.
• Lipid metabolism: Studies have investigated the effects of pinolenic acid on fatty acid oxidation pathways, lipogenic enzyme activity, and triglyceride accumulation in hepatocyte and adipocyte model systems.
• Anti-inflammatory potential: The NMI triene structure has been investigated in the context of eicosanoid biosynthesis modulation and inflammatory signalling pathways.
• Nutritional biochemistry: Used as a reference standard or bioactive substrate in studies examining the bioavailability and metabolism of pine nut oil components.

The ethyl ester form is particularly appropriate for in vitro cell culture experiments where controlled delivery of a lipophilic substrate is required.

Handling, Storage, and Solubilisation Protocol

Proper handling is essential to maintain the chemical integrity of Pinolenic Acid ethyl ester, as polyunsaturated fatty acid esters are susceptible to oxidative degradation.

Storage

• Store at −20 °C in a tightly sealed vial under inert gas (nitrogen or argon).
• Protect from light to prevent photo-oxidation of the polyene system.
• Avoid repeated freeze-thaw cycles; consider preparing single-use aliquots upon first opening.

Solubilisation

• Organic solvent stock solutions: Dissolve in anhydrous ethanol, DMSO, or chloroform to prepare a concentrated stock (e.g., 10–100 mM). Store stock solutions under inert atmosphere at −20 °C.
• Aqueous delivery for cell culture: For cell-based assays, prepare an ethanol or DMSO stock and dilute into culture medium immediately before use. Complexation with fatty acid-free bovine serum albumin (BSA) at a molar ratio of approximately 2:1 to 5:1 (fatty acid:BSA) can improve aqueous dispersibility and reduce cytotoxicity from the solvent vehicle.
• Solvent control: Always include a vehicle-only control at the same final solvent concentration used in experimental wells.

Oxidation Prevention

Work under subdued light conditions. When preparing solutions, briefly purge vessels with nitrogen or argon before capping. Antioxidant additives (e.g., BHT at 0.01%) may be considered for long-term stock solutions but must be documented and accounted for in downstream assays.

Quality Considerations and Purity Assessment

When using Pinolenic Acid ethyl ester in quantitative or mechanistic studies, researchers should be aware of the following quality considerations:

• Purity verification: GC-FID or HPLC analysis of fatty acid methyl/ethyl ester profiles is the standard method for confirming purity and positional isomer content. Confirm that the product certificate of analysis (CoA) specifies the method and purity grade used.
• Isomeric identity: Pinolenic acid (Δ5,9,12) must be distinguished from structurally similar isomers such as γ-linolenic acid (Δ6,9,12) or sciadonic acid (Δ5,11,14). Request GC-MS or NMR data from the supplier if positional isomer confirmation is critical to the experimental design.
• Oxidation indicators: Discard solutions that show yellow/brown discolouration or off-odours indicative of oxidative rancidity. Peroxide value testing can be used to assess oxidative status of lipid stocks.
• Lot-to-lot consistency: Record the lot number for every experiment and retain CoA documentation for regulatory or publication purposes.

Regulatory and Safety Information

Pinolenic Acid ethyl ester is supplied as a research reagent intended for laboratory use only. It is not approved for use in humans or animals as a drug or dietary supplement and must not be used in clinical or veterinary settings without appropriate regulatory authorisation.

Consult the product Safety Data Sheet (SDS) before use. Standard laboratory precautions for handling lipophilic organic compounds apply:

• Use appropriate personal protective equipment (PPE): lab coat, chemical-splash goggles, and nitrile gloves.
• Handle organic solvent stock solutions in a well-ventilated fume hood.
• Dispose of solvent waste in accordance with local institutional and governmental hazardous-waste regulations.

For the most current safety and regulatory information specific to this product, refer to the Aladdin Scientific SDS for SKU P1074224.

Frequently asked questions

What is the difference between pinolenic acid and its ethyl ester, and why does it matter for experiments?

Pinolenic acid is the free polyunsaturated fatty acid, while the ethyl ester is formed by esterification of the carboxylic acid with ethanol. The ethyl ester form is more chemically stable, less prone to ionisation at physiological pH, and easier to handle gravimetrically. In cell-based assays the ester must be hydrolysed by intracellular or extracellular lipases to release the free acid; researchers should confirm that the cell model expresses relevant esterase/lipase activity when choosing between the free acid and ester forms.

How should I prepare an aqueous working solution of Pinolenic Acid ethyl ester for cell culture?

First, dissolve the compound in anhydrous ethanol or DMSO to make a concentrated stock solution (e.g., 10–50 mM) under inert atmosphere. For aqueous delivery, dilute the stock into serum-free or low-serum culture medium immediately before use, keeping the final vehicle concentration ≤0.1% (v/v). To improve dispersibility and mimic physiological delivery, pre-complex the fatty acid ester with fatty acid-free BSA at a molar ratio of approximately 2:1 to 5:1 before adding to cells. Always include a matched vehicle control.

What are the main signs that Pinolenic Acid ethyl ester has degraded, and how can I prevent oxidation?

Oxidative degradation is indicated by a yellow or brown colour change, an off-rancid odour, and reduced biological activity in functional assays. To prevent oxidation: store at −20 °C under nitrogen or argon in the dark, prepare single-use aliquots to avoid repeated freeze-thaw, work under subdued light, and purge all vessels with inert gas before sealing. Peroxide value measurement can quantify the degree of lipid oxidation in stock solutions.

Is Pinolenic Acid ethyl ester the same as gamma-linolenic acid (GLA) ethyl ester?

No. Although both are C18 triene fatty acid ethyl esters, they differ in the positions of their double bonds. Pinolenic acid has double bonds at Δ5, Δ9, and Δ12 (non-methylene-interrupted pattern), whereas GLA has double bonds at Δ6, Δ9, and Δ12 (methylene-interrupted, conventional n-6 series). This structural difference results in distinct biological properties, enzyme substrate specificities, and eicosanoid precursor relationships. Always confirm the regiochemical identity of your material by GC-MS or NMR.

References

1. Druart C, et al. Nutritional intervention with pine nut oil and pinolenic acid: effects on appetite and lipid metabolism. A review of available evidence. (General reference — specific details require verification)
2. Yun G, et al. Pinolenic acid stimulates cholecystokinin (CCK) secretion from intestinal STC-1 cells. (Specific publication details require verification)
3. Barre DE. The role of consumption of alpha-linolenic, eicosapentaenoic and docosahexaenoic acids in human metabolic processes. General textbook-level fatty acid biochemistry reference. (Specific title/authors need verification)

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.