Laurus nobilis

 

Laurus nobilis

Synonyms

No documentation

Vernacular Name

Bay, bay laurel, bay tree, daphne, grecian laurel, laurel, mediterranean bay, noble laurel, roman laurel, true bay.

Description

Sweet Bay, or Laurus nobilis, has a long history of use as a flavoring agent, medicinal herb and source of essential oil. Historically, this tree was sacred to the ancient Greeks; the bay leaves were used to make the head wreaths to crown the Olympians.

L. nobilis, an aromatic evergreen tree, can grow to an extreme height of 18m. The tree has either male or female flowers and must be pollinated by bees.  The small leaves average 8cm long and 3cm wide.  The serrated leaves have a wrinkled margin and are used for many purposes including as a flavoring of foods. 

Origin / Habitat

L. nobilis is native to the Mediterranean area and grows well there and in areas of the Middle East where it can have well-drained soil and the amount of sunlight that it requires.

Chemical Constituents

Flavonoids, including kaempferol; alpha tocopherol, sesquiterpene lactones. [1],[2]

Plant Part Used

Leaf

Medicinal Uses

General

Antioxidant

Antibacterial

Cancer

Improves lipid profile

Improves glucose regulation

 

Most Frequently Reported Uses

Antioxidant

Antibacterial

Dosage

Dosage Range

Dried leaf: 1-3gm daily in divided doses.

Most Common Dosage

One gram powdered herb per day, typically in infusion.

Standardization Dosage 

No standardization known

Pharmacology

Pre-clinical

Laboratory studies report that extracts of L. nobilis leaf have antioxidant activity.[3] One study found the leaf extract to inhibit nitric oxide formation and decrease lipid peroxide formation (highest in bark).[4],[5]

L. nobilis leaf has antibacterial activity, as reported in laboratory studies. One study found that L. nobilis leaf had components active against methicillin-resistant Staphylococcus aureus (MRSA).[6],[7] Also of interest is in laboratory studies, extracts of L. nobilis leaf are reported to inhibit the absorption of alcohol.[8]

In vitro laboratory studies suggest that 1,8-cineole and hot water-soluble sesquiterpenes purified from L. nobilis have an inhibitory effect against human leukemia cells.[9],[10]

Clinical

A small study consisting of 40 patients with type 2 diabetes found that L. nobilis leaf administration (1-3gm daily, dried leaf) improved symptoms associated with diabetes including lowering LDL cholesterol (32-40%), triglycerides (25-34%) and total cholesterol (20-24%) levels while improving HDL (20-29%) and reducing serum glucose levels (from 21-26% after 30 days).[11] The authors concluded that L. nobilis leaf consumption may decrease the risk factors for diabetes and cardiovascular diseases and suggests that L. nobilis leaves may be beneficial for people with type 2 diabetes.

Interaction and Depletions

Interaction with other Herbs

No documentation

Interaction with Drugs

Based on pharmacology, use with caution in individuals with bleeding disorders or those taking blood-thinning medications such as aspirin or warfarin (Coumadin).

Precautions and Contraindications

Side effects

The essential oil of L. nobilis leaf has reported anticonvulsant activity – use only under the supervision of a doctor if you have a seizure disorder.[13]

L. nobilis has been reported safe in recommended doses.

Pregnancy

Not to be used by pregnant or nursing women

Age limitation

No documentation

Adverse reaction

Components in L. nobilis may decrease platelet aggregation, so only use under the supervision of a doctor if a bleeding disorder exists.[12]

Discontinue if allergy occurs.

Read More

  1) Essential Oil

References

  1. Puoci F, Cirillo G, Curcio M, Iemma F, Spizzirri UG, Picci N. Molecularly imprinted solid phase extraction for the selective HPLC determination of alpha-tocopherol in bay leaves. Anal Chim Acta. 19Jun2007;593(2):164-170.
  2. Dall'Acqua S, Viola G, Giorgetti M, Loi MC, Innocenti G. Two new sesquiterpene lactones from the leaves of Laurus nobilis. Chem Pharm Bull (Tokyo). Aug2006;54(8):1187-1189.
  3. Dall'Acqua S, Cervellati R, Speroni E, et al. Phytochemical composition and antioxidant activity of Laurus nobilis L. leaf infusion. J Med Food. Aug2009;12(4):869-876.
  4. De Marino S, Borbone N, Zollo F, et al. New sesquiterpene lactones from Laurus nobilis leaves as inhibitors of nitric oxide production. Planta Med. Aug2005;71(8):706-710.
  5. Simić M, Kundaković T, Kovacević N. Preliminary assay on the antioxidative activity of Laurus nobilis extracts. Fitoterapia. Sep2003;74(6):613-616.
  6. Liu MH, Otsuka N, Noyori K, et al. Synergistic effect of kaempferol glycosides purified from Laurus nobilis and fluoroquinolones on methicillin-resistant Staphylococcus aureus. Biol Pharm Bull. Mar2009;32(3):489-492.
  7. Otsuka N, Liu MH, Shiota S, et al. Anti-methicillin resistant Staphylococcus aureus (MRSA) compounds isolated from Laurus nobilis. Biol Pharm Bull. Sep2008;31(9):1794-1797.
  8. Yoshikawa M, Shimoda H, Uemura T, Morikawa T, Kawahara Y, Matsuda H. Alcohol absorption inhibitors from bay leaf (Laurus nobilis): structure-requirements of sesquiterpenes for the activity. Bioorg Med Chem. Aug2000;8(8):2071-2077.
  9. Komiya T, Yamada Y, Moteki H, Katsuzaki H, Imai K, Hibasami H. Hot water soluble sesquiterpenes [anhydroperoxy-costunolide and 3-oxoeudesma-1,4(15),11(13)triene-12,6alpha-olide] isolated from laurel (Laurus nobilis L.) induce cell death and morphological change indicative of apoptotic chromatin condensation in leukemia cells. Oncol Rep. Jan2004;11(1):85-88.
  10. Moteki H, Hibasami H, Yamada Y, Katsuzaki H, Imai K, Komiya T. Specific induction of apoptosis by 1,8-cineole in two human leukemia cell lines, but not a in human stomach cancer cell line. Oncol Rep. Jul-Aug2002;9(4):757-760.
  11. Khan A, Zaman G, Anderson RA. Bay leaves improve glucose and lipid profile of people with type 2 diabetes. J Clin Biochem Nutr. Jan2009;44(1):52-56.
  12. Ben Amor N, Bouaziz A, Romera-Castillo C, et al. Characterization of the intracellular mechanisms involved in the antiaggregant properties of cinnamtannin B-1 from bay wood in human platelets. J Med Chem. 9Aug 2007;50(16):3937-3944.
  13. Sayyah M, Valizadeh J, Kamalinejad M. Anticonvulsant activity of the leaf essential oil of Laurus nobilis against pentylenetetrazole- and maximal electroshock-induced seizures. Phytomedicine.