Southern Magnolia

Traditional use

These are traditional uses, not proven treatments.

• Southeastern peoples recorded these uses:

  • Choctaw: a wash made by boiling the bark, used for the itching of prickly heat (heat rash). A bath made from the plant was also used for prickly heat.
  • Choctaw: mashed bark steeped in water and used in a steam bath for dropsy, an old name for swelling caused by fluid build-up.
  • Koasati: a wash made by boiling the bark, used on sores.

  [1]Traditional text

• A 2024 review of historical records says Native peoples used magnolias, including Southern Magnolia, for rheumatism and fevers. Older writings described the dried bark as a stimulating tonic that may cause sweating and help the stomach. They also noted it was sometimes swapped for the weaker bark of the tulip tree.[3]Study

  Technical detail: described as tonic, stimulant, diaphoretic and stomachic; substituted with Liriodendron bark.

Laboratory & animal research

Lab and animal results show what might be worth studying in people. They don't show that the herb has these effects in humans.

• In lab tests, a seed extract and three compounds from it (magnolol, honokiol and 4-O-methylhonokiol) attached to cannabinoid receptors, the same receptors cannabis acts on, more strongly than to opioid receptors. They bound most strongly to the CB2 type.[4]Study

  Technical detail: n-hexane seed extract; radioligand binding assays; CB2 Ki 0.29–1.94 μM vs CB1 Ki 3.85–17.82 μM for compounds 1–3.

• In lab tests, compounds from a Southern Magnolia extract slowed the growth of the malaria parasite. Two of them were moderately active, and six were weak.[5]Study

  Technical detail: methanol extract; Plasmodium falciparum; known neolignans 3 and 4 IC50 2.8 and 3.4 μM, others 16.5–114 μM.

• In lab tests, the essential oil from the seeds kept yellow fever mosquitoes from biting about as well as DEET, a common insect repellent. Oils from the unripe and ripe fruit were highly toxic to the mosquitoes, while the leaf, flower and seed oils were much less so.[6]Study

  Technical detail: Aedes aegypti; seed oil biting deterrence index 0.89; 1-decanol (3.3% of seed oil) was the most active compound, LC50 4.8 ppm.

• In lab tests, some compounds from the fruit were toxic to five types of human cancer cells. Some also lowered nitric oxide, a signal of inflammation, in mouse immune cells.[7]Study

  Technical detail: sesquiterpenoids; K562, A549, HepG2, MDA-MB-231 and SW480 cells, IC50 6.07–31.15 μM; LPS-induced NO release in RAW 264.7 macrophages, IC50 6.03–14.46 μM.

Research in people

• In a small trial in Iran, 20 adults aged 18 to 35 were split into two groups. One group used a 0.3% Southern Magnolia bark mouthwash and the other a placebo mouthwash for a week. After a week off, they did the same again for another week.

  While using the magnolia mouthwash, people had fewer Streptococcus mutans in their dental plaque than with the placebo or during the week off. This is a bacterium linked to tooth decay. The study was small and short, and the authors say larger studies are needed.[2]Study

  Technical detail: randomized, single-blind, placebo-controlled; hydro-ethanol bark extract; S. mutans counted by culture; difference statistically significant (paired and independent t-tests).