Anticancer activity of Curcuma aeroginosa essential oil and its nano-formulations: cytotoxicity, apoptosis and cell migration effects.

BACKGROUND AND AIMS: Curcuma aeruginosa, commonly known as "kha-min-dam" in Thai, holds significance in Asian traditional medicine due to its potential in treating various diseases, having properties such as anti-HIV, hepatoprotective, antimicrobial and anti-androgenic activities. This study explores the anticancer activity of C. aeruginosa essential oil (CAEO) and its nano-formulations. METHODS: CAEO obtained from hydrodistillation of C. aeruginosa fresh rhizomes was examined by gas chromatography mass spectroscopy. Cytotoxicity of CAEO was determined in leukaemic K562 and breast cancer MCF-7 cell lines using an MTT assay. Cell cycle analysis and cell apoptosis were determined by flow cytometry. Cell migration was studied through a wound-healing assay. RESULTS: Benzofuran (33.20%) emerged as the major compound of CAEO, followed by Germacrene B (19.12%) and Germacrone (13.60%). Two types of CAEO loaded nano-formulations, nanoemulsion (NE) and microemulsion (ME) were developed. The average droplet sizes of NE and ME were 13.8 ± 0.2 and 21.2 ± 0.2 nm, respectively. In a comparison with other essential oils from the fresh rhizomes of potential plants from the same family (Curcuma longa, Curcuma mangga and Zingiber officinale) on anticancer activity against K562 and MCF-7 cell lines, CAEO exhibited the highest cytotoxicity with IC50 of 13.43 ± 1.09 and 20.18 ± 1.20 µg/mL, respectively. Flow cytometry analysis revealed that CAEO significantly increased cell death, evidenced from the sub-G1 populations in the cell cycle assay and triggered apoptosis. Additionally, CAEO effectively inhibited cell migration in MCF-7 cells after incubation for 12 and 24 h. The developed NE and ME formulations significantly enhanced the cytotoxicity of CAEO against K562 cells with an IC50 of 45.30 ± 1.49 and 41.98 ± 0.96 µg/mL, respectively. CONCLUSION: This study's finding suggest that both nano-formulations, NE and ME, effectively facilitated the delivery of CAEO into cancer cells.

Clerodendrum chinense Stem Extract and Nanoparticles: Effects on Proliferation, Colony Formation, Apoptosis Induction, Cell Cycle Arrest, and Mitochondrial Membrane Potential in Human Breast Adenocarcinoma Breast Cancer Cells.

Breast cancer stands out as the most widespread form of cancer globally. In this study, the anticancer activities of Clerodendrum chinense (C. chinense) stem ethanolic extract were investigated. High-performance liquid chromatography (HPLC) analysis identified verbascoside and isoverbascoside as the major bioactive compounds in the C. chinense stem extract. Successfully developed nanoparticles exhibited favorable hydrodynamic diameter, polydispersity index, and surface charge, thus ensuring stability after four months of storage. The total phenolic content and total flavonoid contents in the nanoparticles were reported as 88.62% and 95.26%, respectively. The C. chinense stem extract demonstrated a dose-dependent inhibitory effect on MCF-7, HeLa, A549, and SKOV-3 cancer cell lines, with IC50 values of 109.2, 155.6, 206.9, and 423 µg/mL, respectively. C. chinense extract and NPs exhibited dose-dependent cytotoxicity and the highest selectivity index values against MCF-7 cells. A dose-dependent reduction in the colony formation of MCF-7 cells was observed following treatment with the extract and nanoparticles. The extract induced cytotoxicity in MCF-7 cells through apoptosis and necrosis. C. chinense stem extract and nanoparticles decreased mitochondrial membrane potential (MMP) and induced G0/G1 phase arrest in MCF-7 cells. In conclusion, use of C. chinense stem extract and nanoparticles may serve as a potential therapeutic approach for breast cancer, thus warranting further exploration.

Biosynthesis of copper oxide nanoparticles using Caesalpinia sappan extract: In vitro evaluation of antifungal and antibiofilm activities against Candida albicans.

Synthesis of nanoparticles using natural organic substances has attracted more attention due to avoiding inorganic toxicity. This work aimed to synthesize copper oxide nanoparticles (CuONPs) using Caesalpinia sappan heartwood extract as a reducing agent. The effects of pH of synthesis reaction were investigated. The obtained CuONPs were characterized using UV-visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. Their particle size, size distribution, and zeta potential were determined using photon correlation spectrophotometry. Candida albicans is a major cause of chronic fungal infections due to its biofilms leading to severe drug resistance problems. In this study, in vitro antifungal and antibiofilm activities as well as killing kinetics of the synthesized CuONPs against C. albicans were investigated. Additionally, fungal biofilm was observed by using confocal laser scanning microscopy. The results showed that the pH of the synthesis reaction played an important role in the physicochemical properties and antifungal activities of the obtained CuONPs. CuONPs synthesized at pH 10 and 12 showed the relatively small and narrow size distribution with high negative zeta potential and time-dependent killing kinetics. Confocal laser scanning microscopy confirms obvious fungal biofilm reduction and increased fungal cell death after exposure to CuONPs. These findings suggest the optimal pH of CuONPs synthesis using C. sappan extract as a reducing agent. The results on antifungal and antibiofilm activities indicate that the obtained CuONPs can be a promising agent for treating fungal infection.

Biological activities of extracts and compounds from Thai Kae-Lae (Maclura cochinchinensis (Lour.) Corner).

BACKGROUND AND AIMS: The purpose of this study was to investigate the biological properties of Kae-Lae (Maclura cochinchinensis (Lour.) Corner), a traditional medicinal plant used in Ayurvedic recipes in Thailand. To achieve this objective, heartwood samples were collected from 12 sources across Thailand. Fractional extracts (n-hexane, ethyl acetate, and ethanol) and the dominant compounds (morin, resveratrol, and quercetin) were examined for their abilities on cytotoxicity, antioxidant, anti-inflammation, and antileukaemic activity (Wilms' tumour 1 protein was used as a well-known biomarker for leukaemic cell proliferation). METHODS: The study used MTT to assess cytotoxicity in leukaemic cells (K562, EoL-1, and KG-1a). Antioxidant activities were evaluated using ABTS, DPPH, and FRAP assays. The anti-inflammatory activity was investigated by detecting IL-2, TNF-α, and NO using appropriate detection kits. Wilms' tumour 1 protein expression was measured by Western blotting to determine the anti-leukaemic activity. The inhibition of cell migration was also analyzed to confirm anticancer progression. RESULTS: Among the tested extract fraction, ethyl acetate No. 001 displayed strong cytotoxicity specifically in EoL-1 cells, while n-hexane No. 008 demonstrated this effect in three cell lines. Resveratrol, on the other hand, displayed cytotoxicity in all the tested cells. Additionally, the three major compounds, morin, resveratrol, and quercetin, exhibited significant antioxidant and anti-inflammatory properties. In particular, resveratrol demonstrated a noteworthy decreased Wilms' tumour 1 protein expression and a reduction in cell proliferation across all cells. Moreover, ethyl acetate No. 001, morin, and resveratrol effectively inhibited MCF-7 cell migration. None of these compounds showed any impact on red blood cell haemolysis. CONCLUSION: Based on these findings, it can be concluded that Kae-Lae has promising chemotherapeutic potential against leukaemic cells, with fractional extracts (ethyl acetate and n-hexane) and resveratrol exhibiting the most potent cytotoxic, antioxidant, anti-inflammatory, and anti-cell migration activities.

Antioxidant, antiglycation, and anti-inflammatory activities of Caesalpinia mimosoides.

Oxidative stress, glycation and inflammation are the main causes of many severe diseases. To date, no single extract has been shown to simultaneously inhibit these three reactions. In this study, the antioxidant, antiglycation and anti-inflammatory activities of ethanol extracts from four edible plants that are commonly used as Thai folk medicine were compared. Among these extracts, Caesalpinia mimosoides extract (CME) showed the highest antioxidant potential with Trolox equivalent antioxidant activity (TEAC) of 5.9 ± 0.1 mM/mg followed closely by Zingiber officinale extract (ZOE) with a TEAC value of 5.4 ± 0.2 mM/mg. However, CME showed no cytotoxicity, whereas ZOE greater than 60 µg/mL showed cytotoxicity to normal human cells. Antiglycation assay using bovine serum albumin-ribose showed comparable potency between CME and Spondias dulcis extract (SDE). However, CME exhibited a high anti-inflammatory activity, significantly higher than SDE and activity depending on the dose. At a concentration of 60 µg/mL, approximately 85% of the interleukin-6 pro-inflammatory cytokine produced from human monocytes, induced by lipopolysaccharides, was completely inhibited by CME whereas SDE showed no inhibition. In summary, CME is the most potential extract with simultaneously activity of these three reactions. CME has the highest total phenolic content expressed as gallic acid equivalent to 301 ± 8 mg/g. Identification using high-performance liquid chromatography revealed the presence of at least four phenolic compounds, gallic acid, syringic acid, p-coumaric acid, and ellagic acid are existed in CME. Our finding suggests that CME is a promising natural source for inhibition of oxidative stress, glycation, and inflammation.

Mucuna pruriens Seed Aqueous Extract Improved Neuroprotective and Acetylcholinesterase Inhibitory Effects Compared with Synthetic L-Dopa.

L-dopa, a dopaminergic agonist, is the gold standard for the treatment of Parkinson's disease. However, due to the long-term toxicity and adverse effects of using L-dopa as the first-line therapy for Parkinson's disease, a search for alternative medications is an important current challenge. Traditional Ayurvedic medicine has suggested the use of Mucuna pruriens Linn. (Fabaceae) as an anti-Parkinson's agent. The present study aimed to quantify the amount of L-dopa in M. pruriens seed extract by HPLC analysis. The cytotoxicity and neuroprotective properties of M. pruriens aqueous extract were investigated by two in vitro models including the serum deprivation method and co-administration of hydrogen peroxide assay. The results showed the significant neuroprotective activities of M. pruriens seed extracts at a concentration of 10 ng/mL. In addition, the effects of L-dopa and M. pruriens seed extract on in vitro acetylcholinesterase activities were studied. M. pruriens seed extract demonstrated acetylcholinesterase inhibitory activity, while synthetic L-dopa enhanced the activity of the enzyme. It can be concluded that the administration of M. pruriens seed might be effective in protecting the brain against neurodegenerative disorders such as Parkinson's and Alzheimer's diseases. M. prurience seed extract containing L-dopa has shown less acetylcholinesterase activity stimulation compared with L-dopa, suggesting that the extract might have a superior benefit for use in the treatment of Parkinson's disease.

Anticancer activity of Zingiber ottensii essential oil and its nanoformulations.

Zingiber ottensii, is widely used in Asian traditional remedies for the treatment of many diseases. The present study explores anticancer activity of Z. ottensii essential oil (ZOEO) and its nanoformulations. ZOEO obtained from hydrodistillation of Z. ottensii fresh rhizomes was analysis using gas chromatography mass spectroscopy. Zerumbone (25.21%) was the major compound of ZOEO followed by sabinene (23.35%) and terpene-4-ol (15.97%). Four types of ZOEO loaded nanoformulations; nanoemulsion, microemulsion, nanoemulgels, and microemulgel, were developed. The average droplet size of the nanoemulsion and microemulsion was significantly smaller than that of the nanoemulgel and microemulgel. Comparison with other essential oils of plants of the same family on anticancer activity against A549, MCF-7, HeLa, and K562, ZOEO showed the highest cytotoxicity with IC50 of 43.37±6.69, 9.77±1.61, 23.25±7.73, and 60.49±9.41 µg/mL, respectively. Investigation using flow cytometry showed that ZOEO significantly increased the sub-G1 populations (cell death) in cell cycle analysis and induced cell apoptosis by apoptotic analysis. The developed nanoformulations significantly enhanced cytotoxicity of ZOEO, particularly against MCF-7 with the IC50 of 3.08±2.58, 0.74±0.45, 2.31±0.91, and 6.45±5.84 µg/mL, respectively. Among the four nanoformulations developed in the present study, nanoemulsion and microemulsion were superior to nanoemulgel and microemulgel in delivering ZOEO into cancer cells.

Essential Oil from Zingiber ottensii Induces Human Cervical Cancer Cell Apoptosis and Inhibits MAPK and PI3K/AKT Signaling Cascades.

Zingiber ottensii (ZO) is a local plant in Thailand and has been used as a Thai traditional therapy for many conditions. ZO has been reported to exhibit many pharmacological effects, including anti-cancer activity. Nevertheless, its anti-cancer effects explored at the signaling level have not been elucidated in cervical cancer, which is one of the leading causes of fatality in females. We discovered that the essential oil of ZO significantly increased the apoptosis of human cervical cancer cells (HeLa) after 24 h of treatment in a concentration-dependent manner. Our data also clearly demonstrated that ZO essential oil reduced IL-6 levels in the culture supernatants of the cancer cells. Moreover, Western blot analysis clearly verified that cells were induced to undergo apoptotic death via caspase activation upon treatment with ZO essential oil. Interestingly, immunofluorescence studies and Western blot analyses showed that ZO essential oil suppressed epidermal growth factor (EGF)-induced pAkt and pERK1/2 signaling pathway activation. Together, our study demonstrates that ZO essential oil can reduce the proliferation and survival signaling of HeLa cervical cancer cells. Our study provides convincing data that ZO essential oil suppresses the growth and survival of cervical cancer cells, and it may be a potential choice for developing an anti-cancer agent for treating certain cervical cancers.

Phytochemical and Safety Evaluations of Zingiber ottensii Valeton Essential Oil in Zebrafish Embryos and Rats.

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.

Formulation optimization, anesthetic activity, skin permeation, and transportation pathway of Alpinia galanga oil SNEDDS in zebrafish (Danio rerio).

Alpinia galanga oil (AGO) has an anesthetic activity but its water insoluble property limits its clinical applications. The aim of the present study was to develop a self-nanoemulsifying drug delivery system of AGO (SNEDDS-AGO) to avoid the use of organic solvent and investigate AGO transportation pathway and anesthetic activity. Three optimized formulations from a contour plots of droplet size; SNEDDS-AGO-1, SNEDDS-AGO-2, and SNEDDS-AGO-3, composed of AGO, Miglyol 812, Cremophor RH 40, Capmul MCM EP, and ethanol at the ratios of 40:10:35:10:5, 40:20:15:20:5, and 60:10:15:10:5, respectively were selected as they possessed different droplet size of 62 ± 0.5, 107 ± 2.8, and 207 ± 4.3 nm, respectively. It was found that the droplet size played an important role in fish anesthesia. SNEDDS-AGO-3 showed the longest anesthetic induction time (270 sec) (p < 0.03). Transportation pathway and skin permeation of SNEDDS-AGO-2 were investigated using nile red labelled AGO and detected by fluorescence microscope. AGO was found mostly in brain, gills, and skin suggesting that the transportation pathway of AGO in zebrafish is passing through the gills and skin to the brain. SNEDDS-AGO formulations showed significantly higher permeation through the skin than AGO ethanolic solution. In conclusion, SNEDDS is a promising delivery system of AGO.

Curcuma amarissima Extract Activates Growth and Survival Signal Transduction Networks to Stimulate Proliferation of Human Keratinocyte.

Many medicinal plants have been used to treat wounds. Here, we revealed the potential wound healing effects of Curcuma amarissima (CA). Our cell viability assay showed that CA extract increased the viability of HaCaT cells that were cultured in the absence of serum. This increase in cell viability was proved to be associated with the pharmacological activities of CA extract in inducing cell proliferation. To further define possible molecular mechanisms of action, we performed Western blot analysis and immunofluorescence study, and our data demonstrated that CA extract rapidly induced ERK1/2 and Akt activation. Consistently, CA extract accelerated cell migration, resulting in rapid healing of wounded human keratinocyte monolayer. Specifically, the CA-induced increase of cell monolayer wound healing was blocked by the MEK inhibitor (U0126) or the PI3K inhibitor (LY294002). Moreover, CA extract induced the expression of Mcl-1, which is an anti-apoptotic protein, supporting that CA extract enhances human keratinocyte survival. Taken together, our study provided convincing evidence that Curcuma amarissima can promote proliferation and survival of human keratinocyte through stimulating the MAPK and PI3K/Akt signaling cascades. These promising data emphasize the possibility to develop this plant as a wound healing agent for the potential application in regenerative medicine.

Effects of Quercetin and Curcumin Combination on Antibacterial, Antioxidant, In Vitro Wound Healing and Migration of Human Dermal Fibroblast Cells.

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.

Boesenbergia rotunda extract accelerates human keratinocyte proliferation through activating ERK1/2 and PI3K/Akt kinases.

Boesenbergia rotunda (BR) has long been used as tradition medicine. For its pharmacological effects on wound healing, previous studies in an animal model provided convincing results that the ethanolic extract from the rhizome of this plant can stimulate wound healing. However, the mechanism about how this plant promotes wound healing at the molecular level has not been elucidated. As a step towards the development of wound healing agents, our current study utilized a human keratinocyte cell line (HaCaT) as an in vitro model to define the potential molecular mechanisms of BR extract in enhancing wound-healing. Our HPLC results showed that BR extract contained kaempferol as one of its potential compounds. The extract strongly promoted wound healing of HaCaT cell monolayer. This effect was eventually defined to be regulated through the ability of BR extract to induce cell proliferation. At the signaling level, we discovered that BR extract rapidly activated ERK1/2 and Akt phosphorylation upon the addition of the extract. Additionally, our experiments where specific inhibitors of MEK (U0126) and PI3K (LY294002) were utilized verified that BR enhanced cell proliferation and wound healing through stimulating the MAPK and PI3K/Akt signal transduction pathways. Moreover, direct inhibition of keratinocyte DNA synthesis by mitomycin C (MMC) could completely block the proliferative effects of BR extract. Nevertheless, data from Transwell migration assay revealed that BR extract did not promote keratinocyte migration. Altogether, we provided more evidence that BR possesses its wound healing-promoting action through the activation of proliferation and survival pathways, and our study suggests that BR is an interesting candidate to be developed as a wound healing-promoting agent.

Isolation and biological activity of agrostophillinol from kaffir lime (Citrus hystrix) leaves.

The leaves of the kaffir lime (Citrus hystrix) are commonly used in cuisine and folk medicine. The aim of this study was to isolate a bioactive compound in kaffir lime leaves and characterize its biological activity. The compound was isolated from a hexane fractional extract and identified as agrostophillinol. This is the first report of agrostophillinol isolated from kaffir lime leaves. In terms of cytotoxicity, agrostophillinol exhibited IC50 values of 36.27 ± 7.30 and 53.44 ± 10.63 µg/mL against EoL-1 and HL60 cells, respectively. Agrostophillinol also exhibited potent anti-inflammatory activity, significantly inhibiting IL-6 secretion.

Antileukemic Cell Proliferation of Active Compounds from Kaffir Lime (Citrus hystrix) Leaves.

Kaffir lime (Citrus hystrix) is a plant member of family Rutaceae, and its leaves are commonly used in folk medicine. The present study explores antileukemic effects of the extracts and purified active compounds from the leaves. The antileukemic activity was investigated via inhibition of Wilms' tumor 1 (WT1), which is a protein that involves in leukemic cell proliferation. In addition, the compounds were investigated for their effects on WT1 gene expression using real time RT-PCR and Western blotting. Cell cycle arrest and total cell number were investigated using flow cytometry and trypan blue exclusion method, respectively. The results demonstrated that the hexane fractionated extract had the greatest inhibitory effect on WT1 gene expression of many leukemic cell lines and significantly decreased WT1 protein levels of K562 cells (representative of the leukemic cells), in a dose- and time-dependent manner. Subfraction No. 9 (F9) after partial purification of hexane fractioned extract showed the highest suppression on WT1 protein and suppressed cell cycle at G2/M. The organic compounds were isolated from F9 and identified as phytol and lupeol. The bioassays confirmed antiproliferative activities of natural products phytol and lupeol. The results demonstrated anticancer activity of the isolated phytol and lupeol to decrease leukemic cell proliferation.

Phytochemical and Safety Evaluations of Volatile Terpenoids from Zingiber Cassumunar Roxb. On Mature Carp Peripheral Blood Mononuclear Cells and Embryonic Zebrafish.

Pharmaceutical products of essential oil from Zingiber cassumunar Roxb. are extensively being developed, while the research on their safety is seldom documented. The aim of the present study was to evaluate the phytochemical profile and the effect of cassumunar ginger oil on cell-based assay and the zebrafish model. The essential oil was isolated from fresh rhizomes of Z. cassumunar using simultaneous steam-distillation. Chemical composition was analyzed using gas chromatograph coupled to a mass spectrometer (GC-MS). Effect of cassumunar ginger oil on adult carp fish peripheral blood mononuclear cells (PBMCs) was investigated using MTT assay. The embryotoxic and teratogenic effects of cassumunar ginger oil were studied in zebrafish embryos. GC-MS results showed that the essential oil was composed of sabinene (43.54%) and terpinen-4-ol (29.52%) as the major phytoconstituents. No fish PBMC cytotoxic effect was observed with the concentration less than 50 µg/mL of cassumunar ginger oil. Our results showed for the first time the embryotoxic and teratogenic effects of cassumunar ginger oil in zebrafish embryos. The result indicated that the cassumunar ginger oil induced zebrafish embryotoxicity in a concentration-dependent manner. At 500 µg/mL of cassumunar ginger oil demonstrated significantly moderated embryotoxicity within 24 h (p < 0.05). The survival rate of 100 µg/mL of cassumunar ginger group was markedly declined to zero at 96-h post-fertilization (log-rank test, p = 0.001). However, survival rates of zebrafish embryo in the 1 and 10 µg/mL cassumunar ginger groups were more than 90% throughout the trial period. Moreover, very low teratogenicity to the zebrafish embryo was also observed in 1 and 10 µg/mL of cassumunar ginger groups. Our findings suggest that there is hardly any cytotoxicity, embryotoxicity and teratogenicity at concentrations less than 10 µg/mL of cassumunar ginger oil. However, the toxicity assessment of its pharmaceutical product should prove for further consumer protection.

Antifungal activity of polymeric micelles of silver nanoparticles prepared from Psidium guajava aqueous extract.

In the present study, silver nanoparticles (AgNPs) were synthesized by green synthesis using Psidium guajava aqueous extract (PE) as a reducing agent and silver nitrate (AgNO3) as a precursor. The obtained AgNPs showed maximum absorbance at 455 nm. The results from energy-dispersive X-ray spectroscopy demonstrate Ag signal at 88.33% weight. The particle image under scanning electron microscopy is spherical shape. The average size of the freshly prepared AgNPs is 96 ± 4 nm but is dramatically increases during storage due to particle aggregation. Coating AgNPs with polymeric micelles of poloxamer 407 (F127) at the suitable ratio can decrease the size of the freshly prepared AgNPs to 70.4 ± 0.8 nm and significantly prevent AgNPs from aggregation. The obtained coated AgNPs showed high effective on inhibition of Candida albicans. Isotonic solutions of 0.9% NaCl and phosphate buffer solution pH 7.4 can cause some extend of aggregation and increase the particle size of the coated AgNPs but the increased size is in the colloidal range that no precipitation occurs during 90 days at room temperature. From our results, it is suggested that the 1:1 ratio of AgNPs/F127 is the most suitable ratio to obtain the AgNPs loaded polymeric micelles with high stability, small particle size, and high inhibitory activity against C. albicans. These AgNPs are the promising antifungal nanomaterials for further study in animal model.

Antioxidant activity and potential of Caesalpinia sappan aqueous extract on synthesis of silver nanoparticles.

The aim of this study was to investigate the antioxidant activity of Caesalpinia sappan aqueous extract (CE) and its potential on synthesis of silver nanoparticles (AgNPs). The antioxidant activity of CE was investigated using ferric reducing antioxidant power (FRAP) assay and two radical scavenging methods using 2,20-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) as free radicals. Silver nitrate (AgNO3) was used as precursor for the synthesis of AgNPs. Effects of AgNO3 concentration, reaction temperature, and duration of reaction were investigated. The obtained AgNPs was characterized using UV-Vis and photon correlation spectrophotometers. The antimicrobial activity of AgNPs was studied by means of diffusion method. The results from FRAP demonstrated that CE had high reducing property of 78.7 ± 2.4 mM Fe2+/mg. The trolox equivalent antioxidant capacity of CE determined by ABTS was 64.8 ± 4.2 µM/mg. The concentration of CE that can inhibit 50% of DPPH radicals (IC50) was 51.2 ± 3.2 µM. These results indicated that CE possesses strong antioxidant and reducing activities. The present study also showed that CE can act as reducing agent to produce AgNPs. The concentration of AgNO3, reaction temperature, and reaction time play an important role on the particles size and zeta potential of the obtained AgNPs. The antimicrobial activity of the AgNPs against Escherichia coli, Candida albicans, and Streptococcus mutants was stronger than against Staphylococcus aureus.

Effect of rice variety and reaction parameters on synthesis and antibacterial activity of silver nanoparticles.

In the present study, three different rice varieties; Jasmine (JM), Niaw Koko-6 (NKK), and Saohai (SH) were determined for reducing power using ferric reducing antioxidant power (FRAP) assay. SH showed the highest reducing property followed by JM and NKK, respectively. All modified rice samples were used to fabricate silver nanoparticles (AgNPs) by reducing silver nitrate (AgNO3) to metallic Ag. The obtained AgNPs from JM, NKK, and SH namely JM-AgNPs, NKK-AgNPs, and SH-AgNPs, respectively, showed maximum absorption at 410, 408, and 409 nm, respectively, which confirmed the spectra of AgNPs. Reaction parameters such as AgNO3 and modified rice concentration as well as the reaction period were investigated. It was found that increasing of these parameters gave better AgNPs until the concentration of modified rice and AgNO3 reached to 0.3% and 10 mM, respectively and the reaction period reached to 60 min, the most suitable AgNPs were obtained. Among the three rice varieties, SH showed the most potential for synthesis of AgNPs. SH-AgNPs showed the smallest size of 80.4 ± 2.8 nm and the highest zeta potential of - 45.9 ± 1.4 mV. The AgNPs obtained from all three rice varieties showed effective against Escherichia coli than Staphylococcus aureus and SH-AgNPs showed significantly higher antibacterial activity than JM- AgNPs and NKK-AgNPs.

Preparation and characterization of rice gels containing tooth bleaching agent.

In the present study, the modified white rice of Jasmine (JM) and Saohai (SH) were used to prepare the rice gels. Carbamide peroxide (CP) containing rice gels (CP rice gels) of JM (CP-JM) and SH (CP-SH) were prepared. The rice gels and CP rice gels show homogenous texture. Rice variety influences the characteristics and properties of the rice gels. Amylose content of JM was lower than SH. Rheological behavior of JM and CP-JM was pseudoplastic without thixotropy whereas that of SH and CP-SH was pseudoplastic with thixotropy. CP-SH showed higher adhesive property and viscosity than CP-JM whereas CP-JM showed faster in vitro drug release than CP-SH. For ex vivo efficacy evaluation, 55 normal human teeth were subjected to the CP rice gels. Samples were applied on tooth surface according to the dental bleaching techniques. For at-home bleaching technique, the CP rice gels with 10% and 20% CP were used with bleaching time of 8h and 4h, respectively. For in-office bleaching technique, the CP rice gels with 35% CP was used with bleaching time of 1 h. The developed CP rice gels showed significantly higher efficacy than the positive and negative controls. For at-home bleaching technique, CP-SH was the most effective gels whereas for in-office bleaching technique, CP-JM was the most effective gels.