Some works directly mention the alpha and beta designated substances – that were (incl. gamma) rather fractions obtained during first historic isolations:<sup>\[1\]</sup>
 
> (…) Oryzanol occurs in the unsaponifiable fraction of rice bran oil and is so named because it was first discovered in rice bran oil (*Orysae Sativa L.*) (Kaneko and Tsuchiya, 1954)<sup>\[2\]</sup> and contained a hydroxyl group. Oryzanol was originally considered a single compound but later was determined to be a mixture of ferulic acids esterified with normal sterols or triterpene alcohols, called **α-**, **β-** and **γ-oryzanol**, of which γ-oryzanol has been the most commonly mentioned. The sterol components of γ-oryzanol are primarily campesterol and sitosterol, and the triterpene alcohol components are cycloartenol and 24-methylene cycloartanol (…)

Other text sound like alpha a beta fractions were not oryzanol at all:<sup>\[3\]</sup>

> (…) During their studies, a number of lipid fractions were isolated from rice bran oil; the third (**gamma**) fraction isolated was **oryzanol**<sup>\[2\]</sup>. Its chemical composition was later identified as a mixture of 
ferulic acid esters of various plant sterols (…)

(Hard to tell, the article<sup>\[2\]</sup> is in Japanese.)

As airhuff already said in his answer, **γ-oryzanol** (or just **oryzanol**) is a mixture of various sterol [ferulates](https://en.wikipedia.org/wiki/Ferulic_acid), which now usually are listed by their chemical names, however a couple of notable compendia<sup>\[4,5\]</sup> list the two major<sup>\[6\]</sup> formerly isolated constituents under names **oryzanol A** and **C** (since B turned out to be a mixture of A and C<sup>\[7\]</sup>).

![Fig. - structures][1]

-   (I) **oryzanol A**, CAS 21238-33-5, cycloartenyl ferulate,  
9,19-cyclo-5α-lanost-24-en-3β-yl (2<i>E</i>)-3-(4-hydroxy-3-methoxyphenyl)prop-2-enoate

-   (II) **oryzanol C**, CAS 469-36-3, 24-methylenecycloartanyl ferulate,  
24-methylidene-9,19-cyclo-5α-lanostan-3β-yl (2<i>E</i>)-3-(4-hydroxy-3-methoxyphenyl)prop-2-enoate

Your structure happens to be oryzanol A (with tiny doubts about some hydrogen stereochemical representation).

---

References:

1.  Huang, C. J. [Potential Functionality and Digestibility of Oryzanol as Determined Using in Vitro Cell Culture Models](https://digitalcommons.lsu.edu/gradschool_dissertations/261), Dissertation thesis, Louisiana State University and Agricultural and Mechanical College, **2003**.
2.  Kaneko, R.; Tsuchiya, T. [New Compound in Rice Bran and Germ Oils](https://doi.org/10.1246/nikkashi1898.57.526). *J. Chem. Soc. Jpn.* **1954**, *57*, 526–529.
3.  Wheeler, K. B.; Garleb, K. A. [Gamma Oryzanol—Plant Sterol Supplementation: Metabolic, Endocrine, and Physiologic Effects](https://doi.org/10.1123/ijsn.1.2.170). *International Journal of Sport Nutrition* **1991**, *1* (2), 170–177.
4.  O’Neil, M. J.; Heckelman, P.; Koch, C.; Roman, K. *The Merck Index*, 14th ed.; **2006**.
5.  Hill, R. A.; Makin, H.; Kirk, D.; Murphy, G. Dictionary of Steroids; CRC Press, **1991**.
6. Xu, Z.; Godber, J. S. [Purification and Identification of Components of γ-Oryzanol in Rice Bran Oil](https://doi.org/10.1021/jf981175j). *J. Agric. Food Chem*. **1999**, *47* (7), 2724–2728. 
7.  Shimizu, M.; Ohta, G. [Studies on the Constituents of Rice Bran Oil. V. Reexamination of Oryzanol-B](https://doi.org/10.1248/cpb.8.108). *Chem. Pharm. Bull.* **1960**, *8* (2), 108–111.


  [1]: https://i.sstatic.net/OHIKt.png