Alpha-Pinene and Beta-Pinene: Occurrence, Measurement, Research and Limits

What the pinenes are

Alpha-pinene and beta-pinene are two related monoterpenes, found in the essential oils of many plants. [1] Both have the formula C10H16, but they are different molecules: PubChem lists alpha-pinene as 2,6,6-trimethylbicyclo[3.1.1]hept-2-ene [2] and beta-pinene as 6,6-dimethyl-2-methylidenebicyclo[3.1.1]heptane. [3] Alpha-pinene is widely distributed in higher plants such as conifers and juniper, and in cannabis. [4] This page is information only and gives no advice to use any terpene.

Alpha-pinene

In cannabis. A study of one hemp variety found (+)-alpha-pinene among the major terpenes made by the plant's enzymes. [5] A 2011 review lists alpha-pinene among the cannabis terpenoids of interest. [6] One study found it higher in CBD-dominant than in THC-dominant varieties. [7]

Forms and lab findings. In laboratory assays, (+)-alpha-pinene and (-)-alpha-pinene showed different profiles for antibacterial and insecticidal activity. [4] Label: preclinical (cells/animals only).

What research shows. The strongest human evidence concerns a popular idea: that pinene offsets the memory problems caused by THC. In a double-blind crossover study, 19 healthy adults inhaled alpha-pinene alone, THC alone, THC with three different pinene amounts, or placebo. Alpha-pinene alone had no significant effects compared with placebo, and adding it to THC did not reduce THC-related memory impairment or change other measured effects. [8] The authors note this is inconsistent with some cannabis industry claims. [8] In cell tests, alpha-pinene and beta-pinene also did not change how THC acted on the TRPA1 and TRPV1 channels. [9] Label: no good evidence of benefit for that claim in this small sample of healthy adults, whose last cannabis use averaged 39 days earlier. [8]

Beta-pinene

In cannabis. Beta-pinene was among the high-amount terpenes in two strains measured by gas chromatography. [10] It was also named among the main terpenoids in 33 cannabis samples. [11]

What research shows. Reviews group alpha- and beta-pinene together and list many reported activities, such as anti-inflammatory, anxiolytic and analgesic effects. [1] Cannabis-terpene pain reviews likewise say that preclinical findings are promising but that clinical translation is limited. [12] In test-tube work, only the positive (+) forms of alpha- and beta-pinene were active against the bacteria and fungi tested. [13] Proper evidence not found for beta-pinene alone in people: the reviews and PubMed searches used for this page located no human trial of beta-pinene by itself. Label: preclinical (cells/animals only) and insufficient evidence.

How pinene is measured and why numbers vary

Labs measure the pinenes by gas chromatography with mass spectrometry or flame ionization detection. [10] One headspace method reported a detection limit of 5 ppm. [11] A pinene value depends on the batch and the method. Ten plants of one strain grown together varied by about 20 percent in the main terpenes. [10] Cultivars in one class can differ substantially in their terpenes. [14] A "pine" description on a menu is an aroma claim, not a measurement. In a comparison of flower and CO2 extract, monoterpenes were lost in extraction, so a concentrate's terpene balance can differ from its source flower. [15]

See Terpene Testing: How Profiles Are Measured and Reported for how to read these results.

Quality and labeling

A pinene figure on a certificate of analysis is a batch measurement. It does not show that a product has a particular effect. See How to Read a Cannabis Certificate of Analysis, The Entourage Effect and Terpenes in Cannabis.