What is Oryzanol?

Is it Safe?

The Main Source?

Effect on the body in General?

Effective dosage of Oryzanol?

 

What is Oryzanol?

It is a nutrient with a strange sounding name that occurs naturally in many plants, especially the rice plant. The Botanical name for rice is Oryza sativa, from which oryzanol gets its name.

The chemical structure is that of two molecules in one, first a plant sterol and second ferulic acid. The sterol (triterpenyl alcohol) is the largest part of the molecule. Hormones such as testosterone, estrogen, progesterone, DHEA and corticosteroids, etc. are derived from cholesterol and can be thought of as modified sterols1. For this reason you may
consider Oryzanol as a universal hormone precursor.

Ferulic acid is one of the hydroxycinnamic acids, a subgroup of plant phenolic acids2. In its purified state, it tastes and smells like cinnamon. Ferulic acid is a precursor for lignin, the polymer that makes up most physical support structures of plants. In rice, ferulic acid is added on to sterols, forming oryzanol. In other plants it is bound to sugars, cell walls,
cellulose, etc., as well as being found in its free form3.

Oryzanol Component of Rice Bran Oil was first presumed to be a single component. But later it was determined to be a fraction containing ferulate (4-Hydroxy-3 Metoxy Cinnamic Acid) esters of Triterpene Alcohols and plant sterols. Cycloartenyl ferulate, campesteryl Ferulate, 24-methylenecycloartanyl ferulate, Sitosteryl Ferulate are the major components and account for 80 percent Oryzanol.

There is no conclusive evidence of the presence of oryzanol in any other plant than rice. This does not mean rice is the only source of oryzanol in nature; methods of plant analysis for compounds similar to oryzanol usually include hydrolysis, which could easily destroy it leaving sterols and ferulic acid as end products. Since rice is a plentiful and economic
source of the nutrient there is not much incentive to do a systematic search for alternative sources.

Records indicate the Japanese were the first to isolate oryzanol from Rice Bran in 1943.
Today, rice is still the only known source of the nutrient.

 


 

Is it Safe?

A long history of rice consumption by man and animals would suggest that gamma oryzanol does not cause much, if any toxicity. Still, Japanese companies have conducted safety tests on gamma oryzanol to satisfy Japanese government regulations regarding food additives and supplements. These tests began with determining if gamma oryzanol is toxic to animals by injecting ever increasing doses to arrive at the LD50 (lethal dose for 50% of the test animals). Such tests have revealed an acute LD50 of greater than 30gm/kg for mice, which would be equivalent to an average adult being injected with over 2100 grams (about 4 pounds) and surviving, meaning gamma oryzanol is extremely NON-
TOXIC!4 Furthermore, feeding large daily doses to baby mice and chicks led to no harmful effects and even caused an increase in body weight over controls. Thus Safe!


 

The Main Source?

Oryzanol was first isolated from Rice Bran Oil and this oil remains the best natural source for the compound. Various methods for its isolation have been described in Literature. The most economically viable raw material for isolation of oryzanol is the soap stock/acid oil obtained as a by-product during chemical/alkali refining of this Oil and the other being Physically refined Rice Bran Oil as that also retains 85-90% of oryzanol content in it.


 

Effect on the body in General?

 


 

Effective dosage of Oryzanol?

Clinical trials conducted in Japan have shown that 300 mg per day is the effective dose of Oryzanol.

Clinical Trials to study the Pharmacological effects of ‘ORYZANOL’

Study Component Daily Dose Study Design(Study Duration) Number of Subjects Pharmacological effect Ref.
Oryzanol 300 mg RCT*(8 weeks) 40 Post- menopausal women TC, LDL-C, TG, Lipid peroxides, HDL-C Ishihara M, Ito , Nakakita T, Maehama T, Hieda S, Yamamoto K and Ueno N
Nippon SankaFujinkaGokkaiZasshi, 34 (1982) 243-251
  300 mg RCT*(8 weeks) 80 Post- menopausal women TC, LDL-C, TG, Lipid peroxides, HDL-C Ishihara, 1984 Asia Oceania J ObstetGynecol 1984;10:317
  300 mg RCT*(13 weeks) 80 Hyper- cholesterolemics TC, LDL-C, TG, Yoshino G, Kazumi T, Amano M, Tateiwa M, Yamasaki T, Takashima S, Iwai M, Hatanaka H & Baba S, CurrTher Res, 45 (1989) 975
  300 mg RCT*(8 weeks) 20 Hyper- cholesterolemics TC, LDL-C, TG, Apolipoprotein B, Sasaki J, Takada Y &Handa K 1990
ClinTherap, 12 (1990) 263-268
  300 mg RCT*(8 weeks) 8 Hypothyroid Patients TSH Shimomura Y, Kobayashi I, Maruto S, Ohshima K, Mori M, Kamio N, Fukuda Endocrinologia Japonica [1980, 27(1):83-86]

TC - Total Cholesterol
LDL - Low Density lipoprotein
TG – Triglycerides
HDL- High Density Lipoprotein
TSH- Thyroid Stimulating Hormone