Maslinic acid is a pentacyclic triterpene existed in the protective wax-like coating of the leaves and fruit of Olea europaea L [1]. Maslinic acid is an inhibitor of NO, H2O2, IL-6 and TNF-α.

In HT29 colon-cancer cells, treatment with maslinic acid significantly inhibited cell proliferation in a dose-dependent manner with the IC50 value of 28.8 ± 0.9 μg/mL. Maslinic acid inhibited the expression of Bcl-2 whilst increasing that of Bax. Maslinic acid stimulated the release of mitochondrial cytochrome-c and ativated aspase-9 and caspase-3 [1]. Maslinic acid inhibited the activity of serine proteases, key enzymes necessary for the spread of HIV within an individual's body. Maslinic acid decreased the cytopathic effect and p24 antigen levels in MT2 cells [2].

In KK-Ay mice, an animal model of genetic type-2 diabetes, oral administration of MA (10 mg/kg) reduced the blood glucose levels. Administration of maslinic acid (10 mg/kg and 30 mg/kg) for 2 weeks significantly reduced the blood glucose levels [3]. Pretreatment with MA attenuated ischemia-induced translocation of NF-κB p65 subunit to the nucleus [4].

References:
[1] Reyes-Zurita F J, Rufino-Palomares E E, Lupiáez J A, et al.  Maslinic acid, a natural triterpene from Olea europaea L., induces apoptosis in HT29 human colon-cancer cells via the mitochondrial apoptotic pathway[J]. Cancer letters, 2009, 273(1): 44-54.
[2] García, A.  Compound from olive-pomace oil inhibits HIV spread. 070709111536, 1-1 (2007).
[3] Liu J, Sun H, Duan W, et al.  Maslinic acid reduces blood glucose in KK-Ay mice[J]. Biological and Pharmaceutical Bulletin, 2007, 30(11): 2075-2078.
[4] Guan T, Qian Y, Tang X, et al.  Maslinic acid, a natural inhibitor of glycogen phosphorylase, reduces cerebral ischemic injury in hyperglycemic rats by GLT‐1 up‐regulation[J]. Journal of neuroscience research, 2011, 89(11): 1829-1839.