Quercetin has been isolated for the first time from ethyl acetate extract of Caesalpinia mimosoides Lamk. C. mimosoides Lamk. (Fabaceae) or Cha rueat (Thai name) is an indigenous plant found in mixed deciduous forest in northern and north-eastern parts of Thailand. Thai rural people consume its young shoots and leaves as a fresh vegetable, as well as it is used for medicinal purposes.The antioxidant capacity in terms of radical scavenging activity of quercetin was determined as IC50 of 3.18 ± 0.07 µg/mL, which was higher than that of Trolox and ascorbic acid (12.54 ± 0.89 and 10.52 ± 0.48 µg/mL, resp.). The suppressive effect of quercetin on both purified and cellular acetylcholinesterase (AChE) enzymes was investigated as IC50 56.84 ± 2.64 and 36.60 ± 2.78 µg/mL, respectively. In order to further investigate the protective ability of quercetin on neuronal cells, P19-derived neurons were used as a neuronal model in this study. As a result, quercetin at a very low dose of 1 nM enhanced survival and induced neurite outgrowth of P19-derived neurons. Furthermore, this flavonoid also possessed significant protection against oxidative stress induced by serum deprivation. Altogether, these findings suggest that quercetin is a multifunctional compound and promising valuable drugs candidate for the treatment of neurodegenerative disease.

Moringa oleifera seed oil has been recognized for its benefits in relation to the skin. The objective of this study was to evaluate the chemical composition and antioxidant activity of moringa seed oil, to formulate a moringa seed oil cream, and to determine the efficacy of moringa seed oil cream in vivo. The chemical components of moringa seed oil were analyzed by high-performance liquid chromatography and gas chromatography. The antioxidant activity of the oil was determined by a 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging assay. An oil-in-water cream containing moringa seed oil was developed and characterized for antioxidant activity. The moringa seed oil cream was further subjected to the accelerated stability test of heating–cooling cycles for six cycles and stored isothermally at 4, 30, and 45 °C for 28 days. The efficacy of moringa seed oil cream was investigated in 32 participants by measuring their skin hydration, erythema, melanin values, and visco-elasticity. The results showed that moringa seed oil contained α-tocopherol, plant sterols, and fatty acids. The oil had antioxidant activity with a 50% of initial concentration (IC50) value of 121.9 mg/mL. The stability study indicated that the pH, viscosity, and rheological behavior of the cream containing moringa seed oil were not significantly changed after storage at 4, 30, and 45 °C for 28 days and six heating–cooling cycles. The moringa seed oil cream exhibited in vitro antioxidant activity and increased the in vivo skin hydration level compared with the cream base. There was no report of skin irritation from moringa seed oil cream application, suggesting that the moringa seed oil cream developed in this study was appropriate for pharmaceutical and cosmetic uses. A M. oleifera seed oil cream was successfully developed. The moringa seed oil cream possessed antioxidant activity, enhanced the skin hydration level, and reduced skin erythema, but did not affect the melanin content and skin visco-elasticity. The moringa seed oil cream did not induce skin irritation and, thus, was safe to use.

Wound healing impairment due to a postponed, incomplete, or uncoordinated healing process has been a challenging clinical problem. Much research has focused on wound care, particularly on discovery of new therapeutic approaches for acute and chronic wounds. This study aims to evaluate the effect of the combination of quercetin and curcuminoids at three different ratios on the antimicrobial, antioxidant, cell migration and wound healing properties. The antioxidant activities of quercetin, curcuminoids and the mixtures were tested by DPPH and ABTS free radical scavenging assays. The disc diffusion method was performed to determine the antibacterial activities of quercetin, curcuminoids and the mixtures against S. aureus and P. aeruginosa. The cytotoxicity and cell migratory enhancing effects of quercetin, curcuminoids and the mixtures against human dermal fibroblasts were investigated by MTT assay, scratch assay and Transwell migration assay, respectively. The results showed the synergism of the quercetin and curcuminoid combination to inhibit the growth of S. aureus and P. aeruginosa, with the inhibition zone ranging from 7.06 ± 0.25 to 8.78 ± 0.38 mm, respectively. The DPPH free radical scavenging assay demonstrated that the combination of quercetin and curcuminoids yielded lower IC50 values (15.38–23.70 µg/mL) than curcuminoids alone (25.75 µg/mL). Quercetin and a 3:1 quercetin/curcuminoid mixture at non-toxic concentrations showed the ability to stimulate the migration of fibroblasts across the matrix, whereas only quercetin alone accelerated the wound closure of fibroblasts. In conclusion, the mixture of quercetin and curcuminoids at a 3:1 ratio was the best formulations for use in wound healing due to the antimicrobial, antioxidant and cell-migration-enhancing activities.

Neuritogenic and neuroprotective activities of litchi (Litchi chinensis Sonn., Sapindaceae) and salacca (Salacca edulis Reinw., Arecaceae) pericarp, and sapodilla (Achras sapota L., Sapotaceae) and tamarind Srichompu cultivar (Tamarindus indica L., Caesalpiniaceae) seed coat extracts were evaluated on cultured cholinergic P19-derived neurons. All the extracts, at a very low concentration (1 ng/mL of litchi and salacca pericarp extracts, 10 ng/mL of sapodilla and 100 ng/mL of tamarind seed coat extracts), enhanced the survival of cultured neurons (% viability more than 100%) by XTT reduction assay. The extracts were further evaluated for their neuritogenicity by observing cell morphology by phase-contrast microscopy and neuroprotective activity in serum deprivation and pre-and co-administration of hydrogen peroxide models. The phase-contrast micrographs displayed that all of the extracts possessed neurogenic activity by promoting the neurite outgrowth of the cultured neurons. Moreover, these extracts can protect neurons from oxidative stress-caused cell death in a serum deprivation model, and prevent and protect neuron cells from the toxicity of hydrogen peroxide. In this study we assured that the neuritogenic and neuroprotective activities of these extracts derived from the phenolic components and flavonoids contained in the extracts by acting as signaling molecules to enhance neuron survival and promote neurite outgrowth. These results suggest that all of the extracts are potentially sources of neuritogenic and neuroprotective components which might be used either as pharmaceutical products or dietary supplements for neurodegenerative disorder patients, for example, those suffering from Alzheimer's disease.

Context: Pluchea indica (L.) Less (Asteraceae) is an herb used as a traditional medicine for wound healing. The chemical compounds found in Pluchea indica leaves are phenolic acids, flavonoids, anthocyanins and carotenoids.Objective: This study investigates the effect of Pluchea indica leaf ethanol extract and its nanoparticles (NPs) on cytotoxicity, cell survival and migration of human oral squamous carcinoma cell line. Materials and methods: Cell viability was measured using MTT assay to assess the effect of Pluchea indica leaf extract and NPs (1-500 lg/mL) on cytotoxicity and cell survival. The effect of Pluchea indica leaf extract and NPs on cell migration was determined by scratch assay. The % relative migration was calculated after 24, 48 and 72 h of treatment.Results: The sizes of Pluchea indica leaf extract NPs were in a range of nanometers. NPs possessed negative charge with the polydispersity index (PDI) smaller than 0.3. After the treatment for 24, 48 and 72 h, Pluchea indica leaf extract had IC 50 value of 443.2, 350.9 and 580.5 lg/mL, respectively, whereas the IC 50 value of NPs after the treatment for 24, 48 and 72 h were 177.4, 149.2 and 185.1 lg/mL, respectively. The % relative migration of cells was significantly increased when the cells were treated with 62.5 and 125 lg/mL of the extract and 62.5 lg/mL of NPs. Discussion and Conclusions: NPs increased cytotoxicity of the Pluchea indica leaf extract, increased the migration of cells at low concentration and increased colloidal stability of the extract in an oral spray formulation. ARTICLE HISTORY