Abstract
Structures of some bioactive phytochemicals in bran extract of the black rice cv. Riceberry that had demonstrated anti-cancer activity in leukemic cell line were investigated. After saponification with potassium hydroxide, separation of the unsaponified fraction by reversed-phase high performance liquid chromatography (HPLC) resulted in four sub-fractions that had a certain degree of anti-proliferation against a mouse leukemic cell line (WEHI-3 cell), this being IC50 at 24 h ranging between 2.80-467.11 μg/mL. Further purification of the bioactive substances contained in these four sub-fractions was performed by normal-phase HPLC. Structural characterization by gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance spectroscopy (NMR) resulted in, overall, the structures of seven phytosterols and four triterpenoids. Four phytosterols, 24-methylene-ergosta-5-en-3β-ol, 24-methylene-ergosta-7-en-3β-ol, fucosterol, and gramisterol, along with three triterpenoids, cycloeucalenol, lupenone, and lupeol, were found in the two sub-fractions that showed strong anti-leukemic cell proliferation (IC50 = 2.80 and 32.89 μg/mL). The other sterols and triterpenoids were campesterol, stigmasterol, β-sitosterol and 24-methylenecycloartanol. Together with the data from in vitro biological analysis, we suggest that gramisterol is a significant anti-cancer lead compound in Riceberry bran extract.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Animals
-
Antineoplastic Agents, Phytogenic / chemistry
-
Antineoplastic Agents, Phytogenic / isolation & purification
-
Antineoplastic Agents, Phytogenic / pharmacology
-
Antineoplastic Agents, Phytogenic / therapeutic use*
-
Cell Line, Tumor
-
Cholesterol / analogs & derivatives
-
Cholesterol / chemistry
-
Cholesterol / isolation & purification
-
Cholesterol / pharmacology
-
Cholesterol / therapeutic use
-
Chromatography, High Pressure Liquid
-
Gas Chromatography-Mass Spectrometry
-
Leukemia / drug therapy*
-
Mass Spectrometry
-
Mice
-
Molecular Structure
-
Oryza / chemistry*
-
Pentacyclic Triterpenes / chemistry
-
Pentacyclic Triterpenes / isolation & purification
-
Pentacyclic Triterpenes / pharmacology
-
Pentacyclic Triterpenes / therapeutic use
-
Phytosterols / chemistry
-
Phytosterols / isolation & purification
-
Phytosterols / pharmacology
-
Phytosterols / therapeutic use*
-
Phytotherapy*
-
Plant Extracts / chemistry
-
Plant Extracts / pharmacology
-
Plant Extracts / therapeutic use
-
Seeds / chemistry*
-
Sitosterols / chemistry
-
Sitosterols / isolation & purification
-
Sitosterols / pharmacology
-
Sitosterols / therapeutic use
-
Stigmasterol / analogs & derivatives
-
Stigmasterol / chemistry
-
Stigmasterol / isolation & purification
-
Stigmasterol / pharmacology
-
Stigmasterol / therapeutic use
-
Triterpenes / chemistry
-
Triterpenes / isolation & purification
-
Triterpenes / pharmacology
-
Triterpenes / therapeutic use*
Substances
-
Antineoplastic Agents, Phytogenic
-
Pentacyclic Triterpenes
-
Phytosterols
-
Plant Extracts
-
Sitosterols
-
Triterpenes
-
lupenone
-
fucosterol
-
campesterol
-
gamma-sitosterol
-
cycloleucalenol
-
Cholesterol
-
Stigmasterol
-
lupeol