Zingiber ottensii (ZO) Valeton, a local plant in Northern Thailand, has been widely used in traditional medicine. Many studies using in vitro models reveal its pharmacological activities, including the anti-inflammatory activity of ZO essential oil, extracted from ZO rhizomes. However, the scientific report to confirm its anti-inflammatory activity using animal models is still lacking. The present study aimed to evaluate the anti-inflammatory activity and explore the possible mechanisms of action of ZO essential oil in rats. The results revealed that ZO essential oil significantly reduced the ear edema formation induced by ethyl phenylpropiolate. Pre-treatment with ZO essential oil significantly reduced the carrageenan-induced hind paw edema and the severity of inflammation in paw tissue. In addition, pre-treatment with ZO essential oil exhibited decreased COX-2 and pro-inflammatory cytokine TNF-α expression in paw tissue, as well as PGE₂ levels in serum. On this basis, our study suggests that ZO essential oil possesses anti-inflammatory activity in animal models. Its possible mechanisms of action may involve the inhibition of TNF-α expression as well as the inhibition of COX-2 and PGE₂ production. These findings provide more crucial data of ZO essential oil that may lead to new natural anti-inflammatory product development in the future.

Zingiber ottensii Valeton (ZO) exhibits pharmacological activity and has long been used in traditional medicine. However, reports about its safety profiles are limited. The present study aimed to evaluate the phytochemical profile and the toxic effects of ZO essential oil on the development of zebrafish and acute oral toxicity in rats. The essential oil was isolated from ZO rhizomes, and phytochemicals were analyzed using a gas chromatography–mass spectrometer (GC–MS). The embryotoxic and teratogenic effects of ZO essential oil were evaluated in zebrafish embryos and larvae and the acute oral toxicity was determined in rats. GC–MS results showed the essential oil contained zerumbone as a major phytoconstituent (24.73%). The zebrafish embryotoxicity of ZO essential oil appeared to be concentration- and time-dependent manner, with a moderate LC₅₀ (1.003 µg/mL). Teratogenicity in zebrafish embryos also included morphological defects, decreased hatchability, and reduced heart rate. In rats, ZO essential oil (2000 mg/kg, p.o.) resulted in no mortality or significant toxicities. These findings suggest that ZO has embryotoxic and teratogenic effects in zebrafish embryos but does not result in death or acute oral toxicity in rats. Further long-term toxicity studies are needed to confirm the safety of products developed from ZO essential oil.

Black rice is a type of rice in the Oryza sativa L. species. There are numerous reports regarding the pharmacological actions of black rice bran, but scientific evidence on its gastroprotection is limited. This study aimed to evaluate the gastroprotective activities of black rice bran ethanol extract (BRB) from the Thai black rice variety Hom Nil (O. sativa L. indica) as well as its mechanisms of action, acute oral toxicity in rats, and phytochemical screening. Rat models of gastric ulcers induced by acidified ethanol, indomethacin, and restraint water immersion stress were used. After pretreatment with 200, 400, and 800 mg/kg of BRB in test groups, BRB at 800 mg/kg significantly inhibited the formation of gastric ulcers in all gastric ulcer models, and this inhibition seemed to be dose dependent in an indomethacin-induced gastric ulcer model. BRB could not normalize the amount of gastric wall mucus, reduce gastric volume and total acidity, or increase gastric pH. Although BRB could not increase NO levels in gastric tissue, the tissue MDA levels could be normalized with DPPH radical scavenging activity. These results confirm the gastroprotective activities of BRB with a possible mechanism of action via antioxidant activity. The major phytochemical components of BRB comprise carotenoid derivatives with the presence of phenolic compounds. These components may be responsible for the gastroprotective activities of BRB. The 2000 mg/kg dose of oral BRB showed no acute toxicity in rats and confirmed, in part, the safe uses of BRB.

Colorectal cancer (CRC) is the third most diagnosed cancer worldwide, and p53 dysfunction plays a significant role in its pathogenesis by impairing cell cycle control and apoptosis. This study aimed to elucidate the phytochemical composition and anticancer potential of extract of residue from clove hydrodistillation (Syzygium aromaticum, SA) and seed extract from Syzygium nervosum (SN). LC-DAD-MS/MS analysis identified gallic acid (2.68%) and ellagic acid (6.70%) as major constituents in SA, while SN contained gallic acid (0.26%), ellagic acid (3.06%), and 2′,4′-dihydroxy-6′-methoxy-3′,5′-dimethylchalcone (DMC) as major constituents. Both extracts exhibited potent antioxidant effects as evidenced by DPPH and ABTS assays. In vitro assays showed that SA and SN significantly inhibited the proliferation of HCT116 (p53 wild-type) colorectal cancer cells, with minimal effects on HT-29 (p53 mutant) cells. Apoptosis was confirmed in HCT116 via Annexin V-FITC/PI staining and increased caspase-3/7 activity. Cell cycle analysis revealed sub-G1 accumulation, accompanied by upregulated p21 and concurrently downregulated cyclin D1 expression, both hallmarks of p53-mediated checkpoint activation. These molecular effects were not observed in HT-29 cells. In conclusion, SA and SN extracts selectively induce apoptosis and cell cycle arrest in p53-functional CRC cells, likely mediated by their phenolic constituents. These findings support their potential as promising plant-derived therapeutic agents for targeted colorectal cancer treatment.