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The skin has a solid protective system that includes the stratum corneum as the primary barrier and a complete antioxidant defence system to maintain the skin's normal redox homeostasis. The epidermal and dermal cells are continuously exposed to physiological levels of reactive oxygen species (ROS) originating from cellular metabolic activities. Environmental insults, such as ultraviolet (UV) rays and air pollutants, also generate ROS that can contribute to structural damage of the skin. The antioxidant defence system ensures that the ROS level remains within the safe limit. In certain skin disorders, oxidative stress plays an important role, and there is an established interplay between oxidative stress and inflammation in the development of the condition. Lower levels of skin antioxidants indicate that oxidative stress may mediate the pathogenesis of the disorder. Accordingly, the total antioxidant level was also found to be lower in individuals with skin disorders in individuals with normal skin conditions. This review attempts to summarise the skin oxidant sources and antioxidant system. In addition, both skin and total antioxidant status of individuals with psoriasis, acne vulgaris, vitiligo and atopic dermatitis (AD), as well as their associations with the progression of these disorders will be reviewed. [ABSTRACT FROM AUTHOR]

Supercritical carbon dioxide (sc-CO2) extraction was carried out on Stereospermum fimbriatum's stem bark in order to obtain an enriched extract containing the targeted active compound. The recovery of its active compound, C1, was compared with the most active Soxhlet's extract of dichloromethane. A minimum inhibitory concentration (MIC) assay was done to examine the antibacterial activity of extracts against methicillin-resistant Staphylococcus aureus. The optimum condition for an enriched extract of sc-CO2 to have a maximum recovery of C1 at MIC value of 400 µg/mL was suggested to be operated at 40°C and pressure at 30 MPa, with addition of 6% co-solvent. [ABSTRACT FROM AUTHOR]

Stereospermum fimbriatum or locally known as "Chicha" is traditionally used for itchy skin, earache, stomachache and postpartum treatments. This study was designed to evaluate the antimicrobial potential of S. fimbriatum's stem bark against 11 pathogens and isolate its bioactive compound. Successive soxhlet extraction was conducted using n-hexane, dichloromethane (DCM) and methanol. Disc diffusion, minimum inhibitory and bactericidal concentration (MIC & MBC) assays were done to examine the antimicrobial activity. Bioassay-guided isolation was conducted on S. fimbriatum's extract. The DCM extract of stem bark (DS) was the most potent extract followed by n-hexane extract of the stem bark (NS). A novel compound was isolated and coded as C1 which demonstrated potent antibacterial effects with the MIC values as low as 3.13 µg/mL to 6.25 µg/mL, against S. epidermidis, MRSA and S. aureus. Thus, S. fimbriatum could be a potential source of antimicrobial agents for the treatment of skin infections, specifically, MRSA. [ABSTRACT FROM AUTHOR]

The development of hydrogel films as wound healing dressings is of a great interest owing to their biological tissue-like nature. Polyvinyl alcohol/polyethylene glycol (PVA/PEG) hydrogels loaded with asiaticoside, a standardized rich fraction of Centella asiatica, were successfully developed using the freeze-thaw method. Response surface methodology with Box-Behnken experimental design was employed to optimize the hydrogels. The hydrogels were characterized and optimized by gel fraction, swelling behavior, water vapor transmission rate and mechanical strength. The formulation with 8% PVA, 5% PEG 400 and five consecutive freeze-thaw cycles was selected as the optimized formulation and was further characterized by its drug release, rheological study, morphology, cytotoxicity and microbial studies. The optimized formulation showed more than 90% drug release at 12 hours. The rheological properties exhibited that the formulation has viscoelastic behavior and remains stable upon storage. Cell culture studies confirmed the biocompatible nature of the optimized hydrogel formulation. In the microbial limit tests, the optimized hydrogel showed no microbial growth. The developed optimized PVA/PEG hydrogel using freeze-thaw method was swellable, elastic, safe, and it can be considered as a promising new wound dressing formulation. [ABSTRACT FROM AUTHOR]

Supercritical fluid extraction (SFE) using carbon dioxide (CO2) and liquid CO2using Soxhlet (CO2-Soxhlet) extraction were employed to extract three (3) antidiabetic compounds viz. stigmasterol, quercetin, and avicularin fromMimosa pudica. Various extraction parameters were studied. Extracts were analyzed pharmacologically, qualitatively and quantitatively to ascertain enrichment levels. All three antidiabetic compounds were effectively enriched under optimized conditions of temperature 60°C, pressure 40 MPa, co-solvent ratio 30%, and CO2flow rate of 5 ml min−1. SFE was found to be the better method for enrichment of the antidiabetic compounds than the CO2-Soxhlet method. Extraction conditions were seen to affect the enrichment of desired compounds. [ABSTRACT FROM AUTHOR]

This study aims to investigate the use of palm olein as the oil phase for betamethasone 17-valerate (BV) emulsions. The physicochemical properties of the formulations were characterized. In vitro drug release study was performed with the Hanson Vertical Diffusion Cell System; the samples were quantified with HPLC and the results were compared with commercial products. Optimized emulsion formulations were subjected to stability studies for 3 months at temperatures of 4, 25, and 40°C; the betamethasone 17-valerate content was analyzed using HPLC. The formulations produced mean particle size of 2-4 μm, viscosities of 50-250 mPa.s, and zeta potential between −45 and −68 mV. The rheological analyses showed that the emulsions exhibited pseudoplastic and viscoelastic behavior. The in vitro release of BV from palm olein emulsion through cellulose acetate was 4.5 times higher than that of commercial products and more BV molecules deposited in rat skin. Less than 4% of the drug was degraded in the formulations during the 3-month period when they were subjected to the three different temperatures. These findings indicate that palm olein-in-water emulsion can be an alternative vehicle for topical drug delivery system with superior permeability. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare α-glucosidase inhibitory activity of Phaleria macrocarpa extracts using subcritical carbon dioxide (subCO2) soxhlet extraction method with sonication and solvent extraction methods. The extraction was performed by subCO2 soxlet using carbon dioxide and the conventional organic solvent-based sonication using ethanol and water, solvent extraction using methanol, and n-hexane solvents. The yields and α-glucosidase inhibitory activity of the P. macrocarpa extracts were analyzed. The yields using sonication, solvent extraction, and subCO2 soxhlet extraction were approximately 10.2 ± 1.0 to 25.4 ± 0.6% and 0.9 ± 0.1 to 2.0 ± 1.0%. The IC50 value of subCO2 soxhlet, sonication, and solvent extraction methods were 4.35, 7.34, and 1.9 µg/mL, respectively. The α-glucosidase inhibitory activity of P. macrocarpa extract using subCO2 soxhlet method was higher than the conventional sonication method and lower than the solvent extraction method. Overall, subCO2 soxhlet extraction of P. macrocarpa represents a promising method to produce organic solvent free and highly α-glucosidase inhibitory compounds containing extracts. Practical applications This study compared the conventional and nonconventional extraction methods for separating bioactive compounds from P. macrocarpa. Plant extracts contain a large variety of bioactive compounds with many other constituents including pharmaceuticals that require separations, purifications, and fractionations for further processing. Pharmaceutical industries are always looking for green processing methods obtaining green products. Nonconventional methods are of great interest owing to their efficiency such as fast, organic-residues-free, low temperature processing, and cost-effective compare to any conventional method. Moreover, nonconventional methods are technologically advanced and claimed to be green with innumerable applications. Bioactive compounds of P. macrocarpa extracted by nonconventional methods may retain the natural quality that is of organic residues free and can be further exploited for the pharmaceutical, cosmetic, functional foods, and neutraceuticals industries. The environmental issues and health concerns of society are also demanding the green technology in our daily life. [ABSTRACT FROM AUTHOR]

A new naturally occurring dibenzylbutyrolactone lignan named isocubebinic ether has been isolated from Knema patentinervia. The structure was established by spectroscopic methods, which include Ultraviolet, Infrared, Nuclear Magnetic Resonance and Mass Spectrometry. The compound showed activity in the stimulation of glucose uptake by 3T3-L1 adipocytes. [ABSTRACT FROM AUTHOR]

Background: Increased usage of cosmetic products has caused a growing concern about the safety of these products, and yet little is known about cosmetics from the consumers' perspective. Hence, this study's aim is to develop a valid and reliable tool for assessing consumers' awareness, perceptions, and attitudes toward cosmetic products. Materials and Methods: A questionnaire was developed in the English language based on information collected from a literature search, in-depth interviews conducted with consumers prior to this study and consultations with experts. Subsequently, the questionnaire was subjected to translation, validation, and test-retest reliability. A final version of the questionnaire was piloted among 66 consumers via convenient sampling. A descriptive analysis was performed, and the internal consistency and the differences between variables in the questionnaire were analyzed. Results: The developed and translated questionnaire produced repeatable data for each of the domains (Spearman's correlation ≥ 0.7, P < 0.001). The internal consistency for awareness, perceptions and attitudes indicates good internal consistency (Cronbach's alpha value of more than 0.7 for each domain). Significant differences were found between the perception scores for the race, religion, and monthly expenses for cosmetic products, respectively, and the same pattern was found for the attitude scores, but monthly expenses for cosmetic products was replaced by monthly income. Conclusion: The results achieved via the Bahasa Malaysia questionnaire indicated that the developed and translated questionnaire can be used as a valid and reliable tool for assessing consumers' awareness, perceptions, and attitudes toward cosmetic products in Malaysia in future studies. [ABSTRACT FROM AUTHOR]

An oral sustained-release floating tablet formulation of metformin HCl was designed and developed. Effervescence and swelling properties were attributed on the developed tablets by sodium bicarbonate and HPMC-PEO polymer combination, respectively. Tablet composition was optimized by response surface methodology (RSM). Seventeen (17) trial formulations were analyzed according to Box-Behnken design of experiment where polymer content of HPMC and PEO at 1: 4 ratio (A), amount of sodium bi-carbonate (B), and amount of SSG (C) were adopted as independent variables. Floating lag time in sec (Y1), cumulative percent drug released at 1 h (Y2) and 12 h (Y1) were chosen as response variables. Tablets from the optimized formulation were also stored at accelerated stability condition (40[degrees]C and 75% RH) for 3 months to assess their stability profile. RSM could efficiently optimize the tablet composition with excellent prediction ability. In-vitro drug release until 12 h, floating lag time, and duration of floating were dependent on the amount of three selected independent variables. Optimized tablets remained floating for more than 24 h with a floating lag time of less than 4 min. Based on best fitting method, optimized formulation was found to follow Korsmeyer-Peppas release kinetic. Accelerated stability study revealed that optimized formulation was stable for three months without any major changes in assay, dissolution profile, floating lag time and other physical properties. [ABSTRACT FROM AUTHOR]

BACKGROUND: Catechin-rich oil palm ( Elaeis guineensis) leaf extract (OPLE) has good cardiovascular and phytoestrogenic properties. The OPLE (0.5 g day−1) was supplemented to young, healthy, adult human volunteers, and their cognitive learning abilities were compared to placebo-controlled groups ( N = 15). Their short-term memories, spatial visualisations, processing speeds, and language skills, were assessed over 2 months by cognitive tests computer programs. RESULTS: Relative to the controls, volunteers taking OPLE had improved ( P < 0.05) short-term memory, after 1 month of intervention which became highly significant ( P < 0.005) after 2 months. The spatial visualisation ability and processing speed improved ( P < 0.05) after 2 months consumption. The dietary OPLE showed neuroprotection in nitric oxide-deficient rats. The mechanisms involved systemic and cellular modulations that eventually enhance neuron survival. The longer the duration of OPLE consumption, the more significant was the enhancement, as shown for short-term memory. CONCLUSION: This is the first report on the cognitive-enhancing effects of dietary OPLE in humans. The computer-assisted cognitive tests were simple, low in cost, errors and man hours, and hence are better than conventional cognitive test methods. In rats, the equivalent OPLE dose showed brain antioxidant enzymes modulating properties and neuroprotection under nitric oxide deficiency, with possibly neurogenesis in normal rats. This supported the effects in humans. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

An alkaloid from Maclurodendron porteri has been isolated and characterized. Extraction process was conducted by acid-base extraction method followed by column chromatography. The structure was established by nuclear magnetic resonance spectroscopy and mass spectrometry. The compound was identified as haplophytin B which occurs commonly in the Rutaceae family. However, this is the first time this alkaloid was isolated and reported from the species. The compound showed no inhibition against Staphylococus aureus, Pseudomonas aeruginosa, Bacillus cereus and Escherichia coli and no cytotoxic activity against H199 and A549 cell lines. [ABSTRACT FROM AUTHOR]