Preparation and optimization of ibuprofen-loaded nanoemulsion formulation

Nanoemulsion containing ibuprofen was developed. However, the composition and method to prepare nanoemulsion were not consistent and needed to be optimised. In this study, nanoemulsion containing a mixture of palm kerneloil esters (PKOE), ibuprofen,Tween 80 (T80), and water was modified from the previous report. It was prepared by a combination of two methods, including low energy and high energy emulsification methods. The composition of nanoemulsion was optimised by a Mixture of Experimental Design (MED), where PKOE, T80, and water were set as variables while droplet size was a response. A total of 15 run experiments were evaluated. An optimum formulation was validated, and the composition of 3.0 wt % of PKOE, 15.0 wt% of Tween 80, 2.0 wt % of ibuprofen and 80.0 wt. % of water with the droplet size of 97.26 nm was obtained.The formulation is stable in the storage at room temperature (25 ± 2 ºC) within 3 months against coalescence process. The polydispersity index and zeta potential of the optimized formulation were 0.271 and -19.8 mV, respectively

Optimization and characterization of palm oil-based nanoemulsion loaded with parthenium hysterophorus crude extract for natural herbicide formulation

The present study revealed the optimization of nanoemulsion containing palm oil derivatives and Parthenium hysterophorus L. crude extract (PHCE) as pre-emergence herbicide formulation against Diodia ocimifolia. The nanoemulsion formulation was prepared by high energy emulsification method, and it was optimized by mixture experimental design (MED). From the optimization process, analysis of variance (ANOVA) showed a fit quadratic polynomial model with an optimal formulation composition containing 30.91% of palm kernel oil ester (PKOE), 28.48% of mixed surfactants (Tensiofix and Tween 80, 8:2), 28.32% of water and 12.29% of PHCE. The reading of both experimental and predicted particle size in the verification experiment were acceptable with a residual standard error (RSE) was less than 2%. Under the optimal condition, the smallest particle size obtained was 140.10 nm, and the particle was shown by morphology analysis to be spherical and demonstrated good stability (no phase separation) under centrifugation and different storage conditions (25 ± 5°C and 45°C). Nanoemulsion stored for 60 days exhibits monodisperse emulsion with a slight increase of particle size. The increase in particle size over time might have contributed by Ostwald ripening phenomenon which is shown by a linear graph from Ostwald ripening rate analysis. In the in vitro germination test, P. hysterophorus nanoemulsion (PHNE) was shown to cause total inhibition of D. ocimifolia seed at lower concentration (5 g L-1) as compared to PHCE (10 g L-1). The finding of the research could potentially serve as a platform for the development of palm oil based formulation containing plant crude extract for green weed management

Optimization of nanoemulsion containing gemcitabine and evaluation of its cytotoxicity towards human fetal lung fibroblast (MRC5) and human lung carcinoma (A549) cells

Background: Gemcitabine (GEM) is a chemotherapeutic agent, which is known to battle cancer but challenging due to its hydrophilic nature. Nanoemulsion is water-in-oil (W/O) nanoemulsion shows potential as a carrier system in delivering gemcitabine to the cancer cell. Methods: The behaviour of GEM in MCT/surfactants/NaCl systems was studied in the ternary system at different ratios of Tween 80 and Span 80. The system with surfactant ratio 3:7 of Tween 80 and Span 80 was chosen for further study on the preparation of nanoemulsion formulation due to the highest isotropic region. Based on the selected ternary phase diagram, a composition of F1 was chosen and used for optimization by using the D-optimal mixture design. The interaction variables between medium chain triglyceride (MCT), surfactant mixture Tween 80: Span 80 (ratio 3:7), 0.9 % sodium chloride solution and gemcitabine were evaluated towards particle size as a response. Results: The results showed that NaCl solution and GEM gave more effects on particle size, polydispersity index and zeta potential of 141.57±0.05 nm, 0.168 and −37.10 mV, respectively. The optimized nanoemulsion showed good stability (no phase separation) against centrifugation test and storage at three different temperatures. The in vitro release of gemcitabine at different pH buffer solution was evaluated. The results showed the release of GEM in buffer pH 6.5 (45.19%) was higher than GEM in buffer pH 7.4 (13.62%). The cytotoxicity study showed that the optimized nanoemulsion containing GEM induced cytotoxicity towards A549 cell and at the same time reduced cytotoxicity towards MRC5 when compared to the control (GEM solution)

Design and development of a nanoemulsion system containing extract of Clinacanthus nutans (L.) leaves for transdermal delivery system by D-optimal mixture design and evaluation of its physicochemical properties

Clinacanthus nutans Lindau (C. nutans) is a well-known medicinal plant in South-East Asia that recently has attracted attention for its therapeutic characteristics and cosmeceutical applications. However, delivering the beneficial attributes of the bioactive ingredients into formulation is challenging due to poor solubility and low bioavailability of bioactive substances, which may hinder their effective transdermal delivery. Therefore, nanoemulsion has been chosen to be a carrier in encapsulation of bioactive ingredients C. nutans extract for pharmaceutical and cosmeceutical formulations. In this work, a D-optimal mixture design was used to determine the optimal composition of nanoemulsion-based system loaded with C. nutans leaves extract. The ultimate goal of the present work was to determine the optimum level of five independent variables (surfactant, oil, xanthan gum, bioactive extract, and water) in the optimal C. nutans nanoemulsion composition with minimum average droplet size. Under the optimal conditions, the predicted average droplet size was 99.99 nm. The actual response showed that the model was in good agreement with the predicted value with residual standard error (RSE) of 2.61%. The optimal nanoemulsion composition was observed to be stable under an accelerated stability study during storage at 25 and 45 ˚C for 90 days, centrifugal force and freeze–thaw cycles. Physicochemical characterizations of the optimal nanoemulsion showed its suitability for transdermal application due to its stability against phase separation

Predicting the optimum compositions of a transdermal nanoemulsion system containing an extract of Clinacanthus nutans leaves (L.) for skin antiaging by artificial neural network model

A nanoemulsion-based formulation containing leaf extracts of Clinacanthus nutans Lindau (C. nutans) was prepared for therapeutic use and optimized by artificial neural network (ANN). The model was applied to optimize the particle size of the transdermal nanoemulsion system containing an extract of C. nutans leaves for skin antiaging. Five universal learning algorithms—incremental back propagation, batch back propagation, quick propagation, genetic algorithm, and Levenberg-Marquardt—were used in the ANN to achieve the optimum topologies. The optimum topologies were selected among the learning algorithms trained with lowest root mean square values. Genetic Algorithm-5-13-1 was found to be the optimum topology for the final model to predict the optimum particle size. Under these conditions, the actual particle size of the optimum nanoemulsion compared well with the predicted values with the residual standard error of less than 1.5%. The final formulation was observed to be stable against phase separation under an accelerated stability study and during storage at room temperature and 45°C for 90 days. The dermal irritation assay demonstrated that the developed nanoemulsion was found to be compatible with human skin and could be classified as nonirritant. In vivo ultrasound attributes of the skin study showed that the collagen content increased significantly with the application of the C. nutans nanoemulsion among all 21 volunteers during the 21 days of the treatment period. Hence, ANN was found to be an effective tool for optimizing the nanoemulsion containing C. nutans leaves extract with efficacy to protect collagen from breakdown

Optimization and kinetic study of lipase-catalyzed synthesis of palm-based kojic acid ester

Palm-based kojic acid ester was produced through lipase-catalyzed esterification of kojic acid with oleic acid using lipase as a catalyst. The chemical and physical characterization of pure palm-based kojic acid ester was analyzed in order to be effectively applied in cosmetic application. The chemical characterization was determined by Fourier-Transform Infrared spectroscopy, Gas Chromatography- Flame Ionization Detector and Nuclear Magnetic Resonance in order to verify and elucidate the structure of product. It was found that kojic acid was esterified at C-5 position to produce palm-based kojic acid ester and the chemical’s name was (E)-6-(hydroxymethyl)-4-oxo-4H-pyran-3-yloctadec-9-enoate. The important physicochemical property of the ester such as skin irritancy test was found to be non-irritating with Human Irritancy Equivalent (HIE) score between 0.55-0.83. Response Surface Methodology and 5-level-4-factor central composite rotatable design were employed in optimizing the synthesis of palm-based kojic acid ester catalyzed by immobilized lipase from Rhizomucor meihei (Lipozyme RM IM) in acetonitrile. Four parameters such as temperature (°C), amount of enzyme (g), substrate molar ratio (kojic acid: oleic acid) and reaction time (h) were studied and their interaction effects were investigated. The optimized reaction conditions obtained after analysis with backward elimination are 0.17 g of enzyme and molar ratio of substrates (OA:KA) corresponding to 1:4 at 52.50°C for 42 h of reaction. Under this condition, the percentage yield of palm-based kojic acid ester produced was 37.2%. The improvement of the synthesis process was carried out in a 2 L stirred-tank reactor (STR) equipped with a multi-impeller design. The types of impeller used were Rushton Turbine (RT), High Efficiency (HE) and Half-pitched Helical Ribbon (HR). The configuration of HE-RT combination showed the highest conversion yield with 77.20% as compared to RT-HE (72.45%) and HR (63.68%). The high Reynolds Number, NRE (3463.89) was achieved at 250 rev/min using HR, which exhibits a transition flow pattern. The production of palm-based kojic acid ester in a 2 L stirred-tank reactor follows Newton’s Law due to the linear relationship in between the shear stress and shear rate. A heterogenous enzyme particles suspension was obtained at 250 rev/min and 30 mm of distance in between the two impellers (RT-HE). A kinetic study, using the experimental data obtained from the batch-mode of 2 L stirred-tank reactor was evaluated for the synthesis of palm-based kojic acid ester. This study was aimed to develop a kinetic model by focusing on the substrates concentration. Different acid and alcohol concentrations were tested systematically and the results were used to identify the best reaction scheme to describe the results obtained over an extended range of conditions. As a result, the kinetic of the reaction can be described by Ping-Pong Bi-Bi mechanism with acid inhibition (palm-based oleic acid). The values of the apparent kinetic parameters were estimated by non-linear regression analysis and computed as: υmax: 4.58 x 10 mmol/L.h.g; Km(KA): 1.87 x 10-7 mmol/L.h.g; Km(OA): 8.31 x 102 mmol/L.h.g ; Ki(OA): 5.32 x 106 mmol/L.h.g. A good agreement between the calculated and the observed value was found. Lipase-catalyzed esterification in a solvent-free system using Novozym 435 lipase was also investigated as a method for kinetic modeling of palm-based kojic acid ester. The structure of palm-based kojic acid ester was also elucidated. It was found that kojic acid was easily esterified at C-7 position to produce palm-based kojic acid ester and the chemical’s name was found to be (E)-(5-hydroxy-4-oxo-4H-pyran-2-yl)methyl octadec-9-enoate. The rate expression of this ester was developed using irreversible second-order power model as a first approach. The activation energy (Ea) shows a value of 7.90 x 104 J/mol and the kinetic reaction constant (ko) of 5.30 x 108 L.mol-1.min-1.gCAT -1. The adsorption value (KKAE) of 1.90 x 10-17 gCAT .gKAE -1 between catalyst and ester was correlated with the Langmuir-Hinshelwood-Hougen-Watson model as a second approach. The Gibbs energy, enthalpy and entropy changes for reaction at different temperature were calculated from the measured equilibrium constant using the integrated Van’t Hoff’s equation. The calculated values for the thermodynamic quantities of Gibbs energy, enthalpy and entropy changes are 2.77 x 104 J/mol, 9.85 x 105 J/mol and 4.77 x 102 J/mol.K, respectively

Development of a kojic monooleate-enriched oil-in-water nanoemulsion as a potential carrier for hyperpigmentation treatment

Introduction: Kojic monooleate (KMO) is an ester derived from a fungal metabolite of kojic acid with monounsaturated fatty acid, oleic acid, which contains tyrosinase inhibitor to treat skin disorders such as hyperpigmentation. In this study, KMO was formulated in an oil-in-water nanoemulsion as a carrier for better penetration into the skin. Methods: The nanoemulsion was prepared by using high and low energy emulsification technique. D-optimal mixture experimental design was generated as a tool for optimizing the composition of nanoemulsions suitable for topical delivery systems. Effects of formulation variables including KMO (2.0%–10.0% w/w), mixture of castor oil (CO):lemon essential oil (LO; 9:1) (1.0%–5.0% w/w), Tween 80 (1.0%–4.0% w/w), xanthan gum (0.5%–1.5% w/w), and deionized water (78.8%–94.8% w/w), on droplet size as a response were determined. Results: Analysis of variance showed that the fitness of the quadratic polynomial fits the experimental data with F-value (2,479.87), a low P-value (P100 µg/mL. Conclusion: The survival rate of 3T3 cell on KMO formulation (54.76%) was found to be higher compared to KMO oil (53.37%) without any toxicity sign. This proved that the KMO formulation was less toxic and can be applied for cosmeceutical applications

Response factorial design analysis on papaingenerated hydrolysates from actinopyga lecanora for determination of antioxidant and antityrosinase activities

Actinopyga lecanora (A. lecanora) is classified among the edible species of sea cucumber, known to be rich in protein. Its hydrolysates were reported to contain relatively high antioxidant activity. Antioxidants are one of the essential properties in cosmeceutical products especially to alleviate skin aging. In the present study, pH, reaction temperature, reaction time and enzyme/substrate ratio (E/S) have been identified as the parameters in the papain enzymatic hydrolysis of A. lecanora. The degree of hydrolysis (DH) with antioxidant activities of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP) assays were used as the responses in the optimization. Analysis of variance (ANOVA), normal plot of residuals and 3D contour plots were evaluated to study the effects and interactions between parameters. The best conditions selected from the optimization were at pH 5.00, 70 °C of reaction temperature, 9 h of hydrolysis time and 1.00% enzyme/substrate (E/S) ratio, with the hydrolysates having 51.90% of DH, 42.70% of DPPH activity and 109.90 Fe2+μg/mL of FRAP activity. The A. lecanora hydrolysates (ALH) showed a high amount of hydrophobic amino acids (286.40 mg/g sample) that might be responsible for antioxidant and antityrosinase activities. Scanning electron microscopy (SEM) image of ALH shows smooth structures with pores. Antityrosinase activity of ALH exhibited inhibition of 31.50% for L-tyrosine substrate and 25.40% for L-DOPA substrate. This condition suggests that the optimized ALH acquired has the potential to be used as a bioactive ingredient for cosmeceutical applications

Identification and Optimisation of Lipase-Catalysed Synthesis of Betulinic Acid Amide in a Solvent System

Betulinic acid amide was synthesized from the enzymatic reaction of betulinic acid and butylamine catalysed by Novozym 435. The effects of different reaction parameters, such as effect of reaction time, reaction temperature, amount of enzyme, and substrate molar ratio (betulinic acid : butylamine), were studied and conventionally optimised. Based on this study, the enzymatic synthesis of betulinic acid amide was found to be 64.6% at the optimum conditions of 24 h, 40°C, 100 mg enzyme, and 1 : 1 substrate molar ratio in 9 : 1 mixture of chloroform and hexane as solvent. The identification of final product was carried out using TLC, melting point, and FTIR and NMR showed the presence of betulinic acid amide

In vitro kinetic release study, in vivo hydration and moisturizing effect of peel-off oil-in-water (O/W) nanoemulsion containing kojic monooleate for topical application

A derivative of kojic acid, kojic monooleate (KMO) contains tyrosinase inhibitor, and exhibits strong antioxidant activity makes it a good candidate to be incorporated into a formulation for topical application. A peel-off was chosen to ensure a better hydration effect and permeability of KMO into the skin. The objectives of this research were to analyze the kinetic release study of peel-off oil-in-water O/W nanoemulsion containing KMO and evaluate the moisturizing and hydration effect towards human volunteers. The peel-off formulation was developed by adding 27.61% w/w polyvinyl alcohol (PVA) and 1.05% w/w propylene glycol (PG). The study was performed by using Franz cell, tewameter and corneometer to analyze the release rate of KMO from peel-off O/W nanoemulsion, moisturizing, and hydration effect of formulation towards humans after 180 min of application, respectively. The final formulation has a pH of 4.74, conductivity of 7.47 ± 4.05 x 10-3 microS/cm, viscosity 0.1058 Pa·s and spreadability of 61.86 ± 1.71 g·cm/s. It also disports 79.99 ± 2.53 % released of KMO across the cellulose acetate membrane after 180 min of study time. The results of the hydration effect of the formulation towards human volunteers’ skin suggested that the peel-off O/W nanoemulsion containing KMO does increase the hydration of the skin by 12.33% due to the occlusive effect of KMO. In summary, this study presents new findings in kinetic release study, hydration and moisturizing effect of peel-off O/W nanoemulsion containing KMO for topical application