Antioxidant and In Vitro Anti-Inflammatory Screening of Ten Nutraceutical Ingredients: Black Ginger (Kaempferia parviflora) Strongly Inhibits Heat-Induced Protein Denaturation

Nutraceutical formulators frequently combine botanical extracts with vitamins, colostrum and tocotrienols, but these ingredients are rarely compared under identical assay conditions. This study evaluated ten ingredients—elderberry, ginseng, astragalus, black ginger (Kaempferia parviflora), ginger, garlic and turmeric extracts, bovine colostrum, tocotrienol and liposomal vitamin C—using two radical-scavenging assays (2,2-diphenyl-1-picrylhydrazyl, DPPH; 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), ABTS) and two in vitro anti-inflammatory assays (lipoxygenase inhibition and inhibition of heat-induced albumin denaturation). Liposomal vitamin C and tocotrienol were the most potent radical scavengers (DPPH half-maximal inhibitory concentrations, IC50, 0.12 and 1.1 mg/mL), followed by turmeric (3.1 mg/mL). Most ingredients inhibited lipoxygenase by approximately 50% at 12.5 mg/mL, and 69–76% at 25 mg/mL. Black ginger extract, despite weak radical scavenging (≤35%), inhibited albumin denaturation by 93.8 ± 2.1% at 25 mg/mL with a sharp threshold between 12.5 and 18.75 mg/mL, the highest maximal inhibition of all samples. The dissociation between radical scavenging and anti-denaturation activity in black ginger indicates a non-radical mechanism and supports its further study as a functional anti-inflammatory ingredient.