Limonene

Limonene (D-limonene) is the second-most common terpene in cannabis after myrcene, present in the majority of sativa and sativa-dominant hybrid strains. Limonene's aroma is unmistakable — bright, sharp citrus notes resembling fresh lemon zest, orange peel, or lime. The terpene is responsible for the entire citrus-family of cannabis aromas: lemon, grapefruit, tangerine, lime. Limonene is the dominant aroma compound in the rinds of all citrus fruits and is widely used in food flavoring, perfumes, and cleaning products. Pharmacology: limonene readily absorbs through inhalation and topical application, crossing the blood-brain barrier and exhibiting documented therapeutic effects. Anti-anxiety activity through serotonin and dopamine system modulation (multiple studies show limonene reduces anxiety in mice with effects comparable to anxiolytic medications). Antidepressant activity through serotonin elevation and neurogenesis stimulation. Anti-inflammatory effects through COX-2 inhibition. Anti-cancer activity in clinical trials (limonene induces apoptosis in breast cancer cells; phase I/II clinical trials in the 1990s showed limonene-rich diets reduced breast tumor recurrence in human subjects). Anti-acid reflux and gastric protection. Cancer prevention via increased levels of liver enzymes that metabolize carcinogens. Strains naturally high in limonene: Super Lemon Haze (1.0-1.8% limonene), Tangie (0.8-1.5%), Wedding Cake (0.6-1.0%), Lemon Skunk (0.7-1.2%), Jack the Ripper (0.6-1.1%), Banana Kush (0.5-0.9%), Do-Si-Dos (0.4-0.8%). The cerebral, motivating, uplifting "sativa effect" is largely driven by high limonene combined with low myrcene — strains with this profile produce energetic mood-elevation suitable for daytime use. Limonene evaporates at 348°F, preserved by vaporizing at lower temperatures. Limonene degrades quickly in light, so high-limonene strains lose their citrus character within 60-90 days unless stored in dark airtight containers.