STEARIC ACID

The rising incidence of superficial fungal infections and the limitations of conventional topical therapies necessitate the development of advanced, targeted delivery systems. This study aimed to develop and evaluate a novel quiniodochlor (QD)-loaded nanostructured lipid carrier (NLC) gel for enhanced topical antifungal therapy. QD-loaded NLCs were prepared by hot homogenization using stearic acid (solid lipid) and cinnamon oil (liquid lipid), stabilized with Tween ® 80, and incorporated into a chitosan hydrogel. Formulations were characterized for particle size, polydispersity index (PDI), zeta potential, entrapment efficiency (EE%), drug release, and physicochemical stability. The developed gel was further evaluated for spreadability, extrudability, ex vivo skin permeation/retention, in vitro antifungal activity against Candida albicans, and in vivo skin irritation. The optimized NLCs exhibited nanoscale particle sizes (141.86-250.79) high EE% (> 98%), and low PDI (0.28-0.43). Despite a near-neutral zeta potential, colloidal stability was maintained, attributed to steric stabilization. The NLC gel showed a sustained drug release profile, significantly higher skin retention, and about 1.6-fold larger zone of inhibition against C. albicans compared to a marketed QD cream. Ex vivo studies confirmed enhanced dermal accumulation with negligible transdermal permeation. The formulation demonstrated excellent spreadability and extrudability, and elicited no signs of erythema or edema in an in vivo skin irritation model. The developed QD-NLC-chitosan gel presents a promising, safe, and effective topical strategy with enhanced skin targeting, sustained local release, and superior antifungal activity, demonstrating strong potential as an advanced therapeutic alternative for superficial mycoses.

Despite the extensive use of synthetic and semi-synthetic lipids in nanostructured lipid carrier (NLC) systems, the utilization of Shorea spp. (Illipe butter or tengkawang fat), an indigenous natural solid lipid from Indonesia, remains unexplored. This study aimed to develop and optimize a Nanostructured Lipid Carrier (NLC) formulation using Illipe butter (Shorea spp.) as a natural solid lipid source. The NLC system was designed through a Box-Behnken design to evaluate the influence of solid lipid (Illipe butter and glyceryl monostearate), liquid lipid (oleic acid), and surfactant mixture (Tween 80 and glycerin) on physicochemical characteristics. The optimized formulation Nanostructured Lipid Carrier-Illipe Butter (NLC-IB) was incorporated into a gel base to produce an NLC gel formulation suitable for topical anti-inflammatory application. Characterization of the optimized NLC revealed a particle size of 276.9 nm, PDI of 0.393, and zeta potential of - 53.5 mV, indicating good stability. Transmission electron microscopy showed spherical particles with an imperfect crystal (Type I) matrix. GC-MS analysis confirmed the retention of major fatty acids, particularly stearic acid (31.9%) and palmitic acid (18.2%), in the NLC system. In vitro anti-inflammatory evaluation using the BSA denaturation assay demonstrated moderate activity, with IC₅₀ values of 197.23 ppm (Illipe butter), 146.46 ppm (NLC-IB), and 238.49 ppm (E-NLC-IB). To our knowledge, this study represents one of the first systematic investigations of Illipe butter (Shorea spp.) as a solid lipid matrix in nanostructured lipid carrier systems.

Clobetasol propionate (CP) is a potent Class I corticosteroid widely used to treat dermatological conditions; however, its poor aqueous solubility limits bioavailability. In this study, a nanostructured lipid carrier (NLC)-based gel was developed via the microemulsion method to improve the topical delivery of CP. The formulation was optimized using stearic acid (solid lipid), Captex 300 (liquid lipid), Tween 20 and Span 80 (surfactants), and propylene glycol (co-surfactant), based on solubility and thermodynamic stability assessments. Vitamin E acetate was incorporated as an antioxidant to inhibit lipid oxidation and enhance formulation stability. The optimized CP-NLC (F5) formulation had a particle size of 75.96 ± 4.87 nm, a zeta potential of -23.88 ± 4.10 mV, and a polydispersity index (PDI) of 0.27 ± 0.11. Encapsulation efficiency was 93.72 ± 0.26%, and drug loading reached 100.69 ± 0.62%. Transmission electron microscopy (TEM) confirmed spherical morphology. The gel (CP-NLC-F5-G) prepared with Carbopol 934 demonstrated a pH of 5.58 ± 0.68 and drug content uniformity of 99.03 ± 1.18%. In vitro release studies using Franz diffusion cells revealed sustained CP release compared to a commercial product. Stability studies indicated long-term encapsulation retention, attributed to the antioxidant effect of Vitamin E acetate. These findings suggest the potential of CP-NLC systems for effective, sustained corticosteroid delivery with enhanced dermal retention.

This study aimed to formulate nanostructured lipid carriers loaded with tea seed or lavender oil to enhance hair regrowth via improved follicular penetration, as an alternative to conventional alopecia therapies. NLCs were prepared by ultrasonication of stearic acid: essential oil mixtures into an aqueous phase containing either Tween 80 or Pluronic F127 as surfactants. Particle size, polydispersity index, zeta potential and TEM were measured. In vivo efficacy was evaluated in female Wistar albino rats given selected once-daily topical NLCs for 30 days. DLS analysis showed that formulations F2 and F5 had mean particle sizes of 165 ± 3 nm and 181 ± 6 nm, respectively, whereas the mixed-oil formulation F3 aggregated into large droplets. Zeta potentials of -65 ± 2 mV (F2) and -42 ± 3 mV (F5) confirmed excellent electrostatic stability. TEM images verified roughly spherical, core-shell nanoparticles. In the in vivo study, F2 and F5 treatments increased mean hair lengths by 120% and 132% versus placebo ( p  < 0.001), respectively, compared to a 116% increase with the commercial product. NLCs significantly enhanced follicular density, with the lavender oil formulation showing superior hair shaft integrity. These results demonstrate that Pluronic F127-stabilized NLCs carrying natural oils possess optimal physicochemical properties and promote hair regrowth.

The increasing problem of antibiotic resistance indicates the need for alternative therapeutic strategies for skin wound infections. While probiotics exhibit potential for developing such alternatives, the majority of antimicrobial studies focus on live cells or lysates and oral delivery. Notably, in dermatology, formulating products with live strains poses technical challenges due to stability issues in water-based systems. Postbiotics, substances made from probiotics, offer a promising, stable, and safe alternative. This study addresses the gap by evaluating the antibacterial potential of cell-free supernatants (CFSs) from six probiotic strains, with a specific focus on Lacticaseibacillus paracasei BGP1, against clinically relevant skin pathogens. CFSs were screened in vitro using agar well diffusion and broth microdilution assays against Staphylococcus aureus ATCC 25923, methicillin-resistant S. aureus (MRSA; UTMC 1442), Pseudomonas aeruginosa ATCC 27853, and P. aeruginosa PAO1. GC-MS analysis was used to identify bioactive compounds in the most promising CFS. Among the tested strains, BGP1 demonstrated both consistent inhibitory (MIC: 6.25 mg/mL) and bactericidal (MBC: 12.5 mg/mL) effects. GC-MS analysis identified palmitic acid (33.24%) and stearic acid (46.45%) as dominant bioactive compounds. These findings provide novel evidence that postbiotic metabolites from L. paracasei BGP1 represent a promising, broad-spectrum, stable, and nonliving candidate to conventional therapies for antibiotic-resistant skin wound infections. Further in vivo research is needed to evaluate their therapeutic potential and formulation in clinical settings.

Saturated and branched high molecular weight organic esters are highly valued as emollients in the cosmetic industry due to their superior properties. Their saturated character provides resistance to oxidation and rancidity. Additionally, their branched structure endows them with low melting temperatures, enabling them to remain liquid over a broad temperature range. These esters can be obtained from branched alcohols, branched fatty acids or both, using chemical or enzymatic processes. Among branched alcohols, Guerbet alcohols stand out. Due to their characteristic properties as branched, saturated alcohols with superior oxidative stability and extremely low volatility, they are proposed as excellent substrates for the enzymatic synthesis of these compounds. This study represents the first investigation into the biocatalytic synthesis of three specific esters: those formed between 2-octyl-1-dodecanol (C20 Guerbet alcohol) and the fatty acids myristic (MA), palmitic (PA), and stearic acid (SA). To achieve this, an environmentally sustainable biocatalytic process was developed. The synthesis involves a solvent-free esterification catalyzed by the commercial immobilized lipase, Lipozyme ® 435, conducted within a vertically stirred, thermostated batch tank reactor. Optimal conditions for lipase concentration and temperature were established, and the sustainability of the process was successfully quantified using various "green metrics".

The current research proposes the preparation of Moxifloxacin-loaded solid lipid nanoparticles through a solvent-free double emulsion technique, to overcome chronic wound healing limitation. The independent variables: stearic acid, Span 80, and Tween 80 were optimized via Box-Behnken design, based on entrapment efficiency (EE%), zeta potential (ZP), and particle size (PS). To statistically optimize the formulation variables, a three-factor, three-level (3³) design involving 15 runs was employed and optimization was carried out to attain maximum EE% and ZP and minimum PS yielding an overall desirability of 0.851. Results indicated that increasing stearic acid enhanced EE%, Span 80 increase PS, and Tween 80 improved ZP. The Optimized SLNs formula had a ZP of - 52.4 mV, EE% of ~ 79.6% and PS of 257 nm. Chemical compatibility was emphasized using FTIR, and XRD studies revealed reduced drug crystallinity within the lipid matrix, which confirmed successful encapsulation. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) imaging revealed nanoparticles with defined spherical shape and smooth surface. The optimized formula is anticipated to enhance dermal distribution and prolonged antibiotic release, thereby offering an efficient therapeutic strategy for the management of chronic wounds.

Candida infections pose a significant health threat, and conventional antifungal drugs like nystatin are limited due to poor solubility, skin permeability, and frequent dosage requirements. Nystatin effectively targets Candida species by disrupting cell membranes, but formulation issues hinder clinical use. Lipid-based vesicular carriers, or novasomes, provide controlled, prolonged drug release and enhanced skin penetration. This study focuses on developing nystatin-loaded novasomal gels as an advanced drug delivery system to enhance therapeutic efficacy, bioavailability, and patient compliance. The formulation was prepared using a modified ethanol injection technique, combining stearic acid, oleic acid, Span 60, cholesterol, and Carbopol to produce a stable transdermal gel. Comprehensive in vitro characterization using FTIR, SEM, XRD, and thermal analysis confirmed the chemical compatibility, morphological uniformity, and physical stability of the nystatin-loaded novasomal gel. Entrapment efficiency differed significantly among the formulations ( p < 0.05), with F7 achieving the highest value (80%). All formulations maintained pH levels within the skin-friendly range of 5.5 to 7.0. Viscosity measurements, ranging from 3900 ± 110 to 4510 ± 105 cP, confirmed their appropriate consistency for dermal use. Rheological analysis showed a dominant elastic response, as indicated by storage modulus values consistently higher than the loss modulus. Particle size ranged from 4143 to 9570 nm, while PDI values remained below 0.3, reflecting uniform particle distribution. Zeta potential values were strongly negative, supporting physical stability. XRD studies indicated reduced crystallinity of nystatin within the formulations, while FTIR confirmed drug-excipient compatibility. SEM images showed spherical particles within the micrometer range. In vitro release studies demonstrated sustained drug release over 12 h, with F6 releasing the highest amount. The novasomal gel formulations-maintained stability for 30 days, with no notable alterations in pH, viscosity, or entrapment efficiency. Antifungal evaluation showed a larger inhibition zone (23 ± 2 mm) compared with the plain drug solution (15 ± 1.6 mm), while the MIC value was reduced (4.57 µg/mL), indicating greater potency. Skin irritation assessment in rats revealed only minor, temporary erythema, and the calculated Primary Irritation Index (0.22) confirmed a non-irritant profile. These findings suggest that the developed novasomal gel offers a promising approach for enhancing the treatment of fungal infections by enabling prolonged drug release, minimizing dosing frequency, and improving patient compliance.

There is growing interest in pigment-free, biocompatible systems that generate structural color for cosmetic applications. This study presents pearlescent cosmetic formulations composed of skin-identical long-chain fatty acids, stearic acid (C18) and behenic acid (C22), that self-organize into multilamellar nanosheet structures in aqueous media. These formulations exhibited vivid, composition-dependent structural colors in the visible region, consistent with constructive interference of reflected light within nanosheet-based lamellar domains. Wavelength shifts were observed in the reflectance spectra as the ratio of stearic to behenic acid varied, indicating tunable optical properties. SAXS confirmed multilamellar structures with interlamellar spacing that varied systematically with composition. This study is the first to demonstrate structural color generation from physiologically relevant fatty acids naturally present in the human stratum corneum. These findings offer a skin-compatible, pigment-free design strategy for multifunctional cosmetic formulations that combine visual aesthetics with biological relevance.

Androgenetic alopecia (AGA) is a multifactorial condition driven by dihydrotestosterone (DHT)-induced follicular miniaturization and reduced perifollicular angiogenesis. Existing treatments such as finasteride, minoxidil, and dutasteride often show limited efficacy and systemic side effects like sexual dysfunction or cardiovascular issues, necessitating targeted approaches. The present study developed dual-drug nanostructured lipid carriers (NLCs) co-delivering spironolactone (SL), an anti-androgen, and 2-deoxy-D-ribose (2dDR), a pro-angiogenic agent, for synergistic follicular regeneration. NLCs were prepared by the hot microemulsion method, incorporating stearic acid as a solid lipid and fenugreek oil as a liquid lipid, with Span 80/Tween 80 surfactants. A Central Composite Design (CCD) was optimised to achieve minimal particle size and optimal zeta potential by varying lipid ratios and surfactant levels. The formulations were characterized by particle size analysis and zeta potential measurements, differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and in vitro drug release kinetics. Cytotoxicity and dihydrotestosterone (DHT)-protection assays were performed using human dermal papilla cells (hDPCs). Optimized SL-2dDR NLCs exhibited a particle size of 343.03 ± 9.0 nm, a PDI of 27.97 ± 2.84%, and a zeta potential of -20.13 ± 0.40 mV. Entrapment efficiency reached 99.00 ± 0.5% for SL and 98.75 ± 0.7% for 2dDR. DSC and XRD confirmed amorphous drug dispersion, while SEM revealed irregular, porous morphology favorable for follicular adhesion. In vitro release followed Higuchi kinetics for SL (R 2  = 0.994) and Hixson-Crowell for 2dDR (R 2  = 0.985). MTT assays demonstrated concentration-dependent cytoprotection against DHT-induced cytotoxicity, maintaining 82% cell viability at 50 µg/mL. The dual-drug NLC system represents a promising targeted therapy for AGA, combining anti-androgenic and pro-angiogenic mechanisms while minimizing systemic exposure.

Background : Lewisite, a potent chemical warfare agent, induces rapid and progressive cutaneous damage, necessitating treatment strategies that offer both immediate decontamination and prolonged therapeutic action. This study aimed to develop and evaluate a composite topical formulation comprising 4-phenylbutyric acid (4-PBA)-loaded emulsomes embedded within a foam vehicle to address both aspects of vesicant-induced skin injury intervention. Methods : Emulsomes composed of a stearic acid-cholesterol solid lipid core stabilized by a lecithin shell were prepared via thin film hydration and optimized by varying lipid ratios and drug loading parameters. Formulations were characterized for drug loading, particle size, and zeta potential. Physicochemical compatibility was assessed using Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) analyses. Stability was evaluated under accelerated refrigerated (25 °C/60% RH) and room temperature (40 °C/75% RH) conditions. The optimized formulation was incorporated into a foam base and evaluated for decontamination efficiency, drug release kinetics, in vitro permeation, and in vivo efficacy. Results : The selected formulation (E2) exhibited high drug loading (17.01 ± 0.00%), monodisperse particle size (PDI = 0.3 ± 0.07), and stable zeta potential (-40 ± 1.24 mV). FTIR and DSC confirmed successful encapsulation with amorphous drug dispersion. The emulsome-foam demonstrated dual functionality: enhanced decontamination (66.84 ± 1.27%) and sustained release (~30% over 24 h), fitting a Korsmeyer-Peppas model. In vitro permeation showed significantly lower 4-PBA delivery from E2 versus free drug, confirming sustained release, while in vivo studies demonstrated therapeutic efficacy. Conclusions : This emulsome-foam system offers a promising platform for topical treatment of vesicant-induced skin injury by enabling both immediate detoxification and prolonged anti-inflammatory drug delivery.

The genus Salvia is a rich source of bioactive compounds with diverse applications in traditional medicine, as well as in the food, and pharmaceutical industries. This study evaluated the essential oil content and composition, seed oil yield, and fatty acid profiles of five native Iranian Salvia species ( S. nemorosa , S. spinosa , S. syriaca , S. palaestina , and S. multicaulis ) cultivated under uniform ecological conditions. Essential oils were extracted using a Clevenger apparatus based on the hydrodistillation method, while seed oils were obtained via Soxhlet extraction with hexane as the solvent. Both were subsequently analyzed by GC-MS and GC-FID. Results revealed significant interspecific variation. Essential oil content ranged from 0.014% (v/w) in S. nemorosa to 0.37% (v/w) in S. multicaulis . In contrast, the highest seed oil content (53.3% v/w) was found in S. nemorosa , while the lowest (18% v/w) was recorded in S. syriaca . S. nemorosa was rich in spathulenol and caryophyllene derivatives, whereas S. spinosa was dominated by isopentyl isovalerate. S. syriaca and S. palaestina primarily contained germacrene D, while S. multicaulis showed high levels of isoborneol, bornyl acetate, and 1,8-cineole. Palmitic, stearic, linoleic, and linolenic acids were detected in the seed oil of all studied Salvia species. S. multicaulis exhibited the highest levels of palmitic (10.92% ± 0.33% v/w) and linoleic acid (52.57% ± 4.57% v/w), S. palaestina had the highest stearic acid content (2.92% ± 0.045% v/w), and S. nemorosa contained the highest linolenic acid level (46.3% ± 0.594% v/w). Overall, S. multicaulis stood out for its high essential oil content, rich in isoborneol and bornyl acetate, whereas S. nemorosa exhibited the highest seed oil content dominated by linolenic acid. These findings suggest that S. multicaulis and S. nemorosa are promising candidates for essential oil and edible oil production, respectively, offering valuable potential for application in the pharmaceutical, cosmetic, and food industries.