Chlorogenic acid, isoorientin, and swertiajaponin were identified as the active constituents in lemongrass that possess antioxidant properties. They help prevent endothelial dysfunction via a nitric oxide-independent vasodilatador effect on blood vessels ⁽⁴⁶⁾. In vitro, anti-inflammatory effects of lemongrass occur through inhibition of IL-1beta ⁽²⁶⁾, and proteasome and nuclear factor-kappaB pathways by chlorogenic acid ⁽⁴⁷⁾. In rat cerebellar granule neuron cultures, neuroprotective effects were attributed to antiapoptotic activity that occurred with cell cycle arrest in the G0G1 phase ⁽²⁷⁾.

In animal models, anti-allergic and anti-inflammatory effects were attributed to the major constituents citral and geranial ⁽³³⁾. The anti-inflammatory effects of citral were further attributed to PPAR-gamma activation ⁽³⁸⁾. Lemongrass inhibits release of the inflammation marker myeloperoxidase from neutrophils and suppresses IL-6 and IL-1alpha production in mice peritoneal macrophages ⁽¹³⁾. A lemongrass hexane extract modulated allergic asthma via inhibition of nuclear factor kappa B activation ⁽³⁴⁾. Analgesic effects by the constituent citronellol are attributed to inhibition of peripheral mediators as well as central inhibitory mechanisms ⁽²²⁾. Anxiolytic activity of lemongrass appeared to be mediated by the GABAergic system ⁽³⁵⁾. It also altered onset and duration of convulsions and potentiated sleep time through GABAergic mechanisms ⁽³⁾, and increased seizure threshold by blocking seizure propagation ⁽¹⁵⁾.

In humans, the erythropoiesis-boosting effects following lemongrass tea consumption are likely due to its nutritional constituents and antioxidant and pharmacologic properties  ⁽⁴³⁾. As aromatherapy to revert reactive anxiety, lemongrass essential oil appears to act through the olfactory or nose-to-brain pathways to restore homeostasis ⁽⁴⁵⁾.

Several constituents in lemongrass demonstrate anticancer activity. Isointermedeol upregulates tumor necrosis factor receptor 1 leading to apoptosis through the extrinsic Fas pathway ^(2) (11). It also increases mitochondrial expression and activation of caspase-9 via the intrinsic cell death pathway. Citral induced apoptosis via caspase-3 enzymatic activity in human leukemia and breast cancer cells ⁽⁸⁾, and induced glutathione S-transferase (GST) through an electrophilic interaction with glutathione in rat liver epithelial cells. GST functions in cell detoxification by rescuing cells from oxidative damage and carcinogenic compounds ^(9) (12). Cytotoxicity was attributed to the presence of an unsaturated aldehyde group, which is specific to the geranial isomer of citral ⁽⁹⁾. Polysaccharides from lemongrass produced cytotoxic and apoptotic effects in cervical and prostate carcinoma cells via caspase 3 upregulation and Bcl-2 downregulation followed by cytochrome c release ⁽²⁹⁾, and antitumor and immunomodulatory activities in sarcoma-180 tumor cells were attributed to immunoenhancement rather than direct cytotoxicity ⁽³¹⁾.