Wound Healing Study of Eucalyptus Essential Oil Containing Nanoemulsion in Rat Model

Evaluation of Antidepressant Activity of Capsaicin Nanoemulsion in Nicotine Withdrawal-Induced Depression in Mice

Depression is a low-energy condition that has an impact on a person's thoughts, actions, propensities, emotional state, and sense of wellbeing. According to the World Health Organization (WHO), 5% of adults are depressed. Individuals who are depressed are commonly prescribed antidepressants, and sometimes, individuals may have other psychiatric conditions that share overlapping symptoms with depression. These cooccurring conditions can complicate the diagnostic process, leading to a misdiagnosis and the prescription of antidepressants. Capsaicin (CAP) is a known antidepressant. Hence, this study aimed to assess the antidepressant activity of CAP nanoemulsion in nicotine (NC) withdrawal-induced depression in mice. Mice treated with CAP (3 mg/kg) showed reduced immobility in the forced swimming test (FST), tail-suspension test (TST), and open field test (OFT). During the OFT, the animals treated with nanoemulsion (CAP 3 mg/kg) spent less time in the corners than the control animals. Biochemical parameters, such as superoxide dismutase (SOD) and glutathione (GSH), were observed in reduced quantities in the NC withdrawal model (NWM), where they were slightly increased in the high-dose nanoemulsion (CAP 3 mg/kg) compared to the low-dose nanoemulsion (CAP 1 mg/kg). These results suggest that CAP caused antidepressant activity in the NWM via the nanoemulsion.

Evaluation of the Physicochemical and Antimicrobial Properties of Nanoemulsion-Based Polyherbal Mouthwash

A nanoemulsion-based polyherbal mouthwash (PHFX) of Curcuma longa hydroalcoholic extract was developed and evaluated for its antibacterial effects against a variety of Gram-positive and Gram-negative oral pathogens in comparison to standard chlorhexidine acetate (CHD-A) (positive control). Various nanoemulsion-based mouthwashes of C. longa extract were produced using an aqueous phase titration approach via construction of pseudoternary phase diagrams. The developed nanoemulsion-based PHFX was studied for thermodynamic stability tests. Selected formulations (PHFX1-PHFX5) were characterized physicochemically for droplet diameter, polydispersity index (PDI), refractive index (RI), transmittance, and pH. The drug release studies were performed using the dialysis method. Based on the minimum droplet diameter (26.34 nm), least PDI (0.132), optimal RI (1.337), maximum %T (99.13), optimal pH (6.45), and maximum cumulative drug release (98.2%), formulation PHFX1 (containing 0.5% w/w of C. longa extract, 1.5% w/w of clove oil, 7.0% w/w of Tween-80, 7.0% w/w of Transcutol-HP, and 84.0% w/w of water) was selected for antimicrobial studies in comparison to standard CHD-A. The antibacterial effects and minimum inhibitory concentration were studied against various Gram-positive oral pathogens such as Streptococcus mutans, Staphylococcus aureus, Streptococcus pneumoniae, and Bacillus subtilis and Gram-negative oral pathogens such as Escherichia coli and Klebsiella pneumoniae. The antibacterial effects of PHFX1 were found to be significant over standard CHD-A against most Gram-positive and Gram-negative oral pathogens. The antimicrobial studies showed that the formulation PHFX1 was effective against all oral pathogens even at 3- to 4-fold lower working concentrations. These findings indicated the potential of nanoemulsion-based mouthwash in the treatment of a variety of oral pathogen infections.

Multifunctional lipid-based nanoparticles for wound healing and antibacterial applications: A review

Wound healing primarily involves preventing severe infections, accelerating healing, and reducing pain and scarring. Therefore, the multifunctional application of lipid-based nanoparticles (LBNs) has received considerable attention in drug discovery due to their solid or liquid lipid core, which increases their ability to provide prolonged drug release, reduce treatment costs, and improve patient compliance. LBNs have also been used in medical and cosmetic practices and formulated for various products based on skin type, disease conditions, administration product costs, efficiency, stability, and toxicity; therefore, understanding their interaction with biological systems is very important. Therefore, it is necessary to perform an in-depth analysis of the results from a comprehensive characterization process to produce lipid-based drug delivery systems with desired properties. This review will provide detailed information on the different types of LBNs, their formulation methods, characterisation, antimicrobial activity, and application in various wound models (both in vitro and in vivo studies). Also, the clinical and commercial applications of LBNs are summarized.

Potential of nanoemulsions for accelerated wound healing: innovative strategies

Wounds represent various significant health concerns for patients and also contribute major costs to healthcare systems. Wound healing comprises of overlapped and various coordinated steps such as homeostasis, inflammation, proliferation, and remodeling. In response to the failure of many strategies in delivering intended results including wound closure, fluid loss control, and exhibiting properties such as durability, targeted delivery, accelerated action, along with histocompatibility, numerous nanotechnological advances have been introduced. To understand the magnitude of wound therapy, this systematic and updated review discussing the effectiveness of nanoemulsions has been undertaken. This review portrays mechanisms associated with wound healing, factors for delayed wound healing, and various technologies utilized to treat wounds effectively. While many strategies are available, nanoemulsions have attracted the tremendous attention of scientists globally for the research in wound therapy due to their long-term thermodynamic stability and bioavailability. Nanoemulsions not only aid in tissue repair, but are also considered as an excellent delivery system for various synthetic and natural actives. Nanotechnology provides several pivotal benefits in wound healing, including improved skin permeation, controlled release, and stimulation of fibroblast cell proliferation. The significant role of nanoemulsions in improved wound healing along with their preparation techniques has also been highlighted with special emphasis on mechanistic insights. This article illustrates recent research advancements for the utilization of nanoemulsions in wound treatment. An adequate literature search has been conducted using the keywords 'Nanoemulsions in wound healing', 'Wound therapy and nanoemulsions', 'Herbal actives in wound therapy', 'Natural oils and wounds treatment' etc., from PubMed, Science Direct, and Google Scholar databases. Referred and original publications in the English language accessed till April 2022 has been included, whereas nonEnglish language papers, unpublished data, and nonoriginal papers were excluded from the study.

The Therapeutic Wound Healing Bioactivities of Various Medicinal Plants

The skin serves as the body's first line of defense, guarding against mechanical, chemical, and thermal damage to the interior organs. It includes a highly developed immune response that serves as a barrier against pathogenic infections. Wound healing is a dynamic process underpinned by numerous cellular activities, including homeostasis, inflammation, proliferation, and remodeling, that require proper harmonious integration to effectively repair the damaged tissue. Following cutaneous damage, microorganisms can quickly enter the tissues beneath the skin, which can result in chronic wounds and fatal infections. Natural phytomedicines that possess considerable pharmacological properties have been widely and effectively employed forwound treatment and infection prevention. Since ancient times, phytotherapy has been able to efficiently treat cutaneous wounds, reduce the onset of infections, and minimize the usage of antibiotics that cause critical antibiotic resistance. There are a remarkable number of wound-healing botanicals that have been widely used in the Northern Hemisphere, including Achiella millefolium, Aloe vera, Althaea officinalis, Calendula officinalis, Matricaria chamomilla, Curcuma longa, Eucalyptus, Jojoba, plantain, pine, green tea, pomegranate, and Inula. This review addresses the most often used medicinal plants from the Northern Hemisphere that facilitate the treatment of wounds, and also suggests viable natural alternatives that can be used in the field of wound care.

Garlic and ginger essential oil-based neomycin nano-emulsions as effective and accelerated treatment for skin wounds' healing and inflammation: In-vivo and in-vitro studies

Skin, largest organ of human, is directly exposed to environment and hence is prone to high rates of injuries and microbial infections. Over the passage of time these microbes have developed resistance to antibiotics making them ineffective especially in lower doses and hence, higher dosages or new drugs are required. The current study deals with designing of nano-emulsion (NE) formulations composed of garlic and ginger oils (0.1 %) with neomycin sulphate used in different ratios (0.001, 0.01 and 0.1 %) and combinations. The resulting NEs were characterized for droplet size (145-304 nm), zetapotential (-3.0-0.9 mV), refractive index (1.331-1.344), viscosity (1.10-1.23cP), transmittance (96-99 %), FT-IR and HPLC and found stable over a period of three months. All NEs were also found effective against both gram positive and negative bacterial strains i.e., B. spizizenii, S. aureus, E. coli and S. enterica as compared to pure neomycin sulphate (NS) used as control with highest activity recorded for NE-2 and NE-4 against all strains showing zone of inhibition in range of 22-30 mm and 21-19 mm, respectively. NEs were also tested using rabbit skin excision wound model which potentiates that all the NEs resulted in early recovery with 86-100 % wound healing achieved in 9 days as compared to NS ointment (71 %). The studies confirmed that essential oils when used in combination with traditional drug can lead to much higher efficacies as compared to pure drugs.

Appraisal on the Wound Healing Potential of Deverra tortuosa DC. and Deverra triradiata Hochst Essential Oil Nanoemulsion Topical Preparation

Deverra tortuosa (Desf.) DC. and Deverra. triradiata Hochst. ex Bioss are perennial desert shrubs widely used traditionally for many purposes and they are characteristic for their essential oil. The objective of the present study was to investigate the in vivo wound healing activity of the essential oil (EO) of D. tortuosa and D. triradiata through their encapsulation into nanoemulsion. EO nanoemulsion was prepared using an aqueous phase titration method, and nanoemulsion zones were identified through the construction of phase diagrams. The EO was prepared by hydrodistillation (HD), microwave-assisted hydrodistillation (MAHD), and supercritical fluid extraction (SFE) and analyzed using GC/MS. D. tortuosa oil is rich in the non-oxygenated compound, representing 74.54, 73.02, and 41.19% in HD, MADH, and SFE, respectively, and sabinene represents the major monoterpene hydrocarbons. Moreover, D. triradiata is rich in oxygenated compounds being 69.77, 52.87, and 61.69% in HD, MADH, and SFE, respectively, with elemicin and myristicin as major phenylpropanoids. Topical application of the nanoemulsion of D. tortuosa and D. triradiata (1% or 2%) exhibited nearly 100% wound contraction and complete healing at day 16. Moreover, they exhibit significant antioxidant and anti-inflammatory effects and a significant increase in growth factors and hydroxyproline levels. Histopathological examination exhibited complete re-epithelialization accompanied by activated hair follicles and abundant collagen fibers, especially at a concentration of 2%. Therefore, the incorporation of the two Deverra species into nanoemulsion could professionally endorse different stages of wound healing.

An Investigation for Skin Tissue Regeneration Enhancement/Augmentation by Curcumin-Loaded Self-Emulsifying Drug Delivery System (SEDDS)

Diabetes, one of the global metabolic disorders, is often associated with delayed wound healing due to the elevated level of free radicals at the wound site, which hampers skin regeneration. This study aimed at developing a curcumin-loaded self-emulsifying drug delivery system (SEDDS) for diabetic wound healing and skin tissue regeneration. For this purpose, various curcumin-loaded SEDDS formulations were prepared and optimized. Then, the SEDDS formulations were characterized by the emulsion droplet size, surface charge, drug content/entrapment efficiency, drug release, and stability. In vitro, the formulations were assessed for the cellular uptake, cytotoxicity, cell migration, and inhibition of the intracellular ROS production in the NIH3T3 fibroblasts. In vivo, the formulations' wound healing and skin regeneration potential were evaluated on the induced diabetic rats. The results indicated that, after being dispersed in the aqueous medium, the optimized SEDDS formulation was readily emulsified and formed a homogenous dispersion with a droplet size of 37.29 ± 3.47 nm, surface charge of -20.75 ± 0.07 mV, and PDI value of less than 0.3. The drug content in the optimized formulation was found to be 70.51% ± 2.31%, with an encapsulation efficiency of 87.36% ± 0.61%. The SEDDS showed a delayed drug release pattern compared to the pure drug solution, and the drug release rate followed the Fickian diffusion kinetically. In the cell culture, the formulations showed lower cytotoxicity, higher cellular uptake, and increased ROS production inhibition, and promoted the cell migration in the scratch assay compared to the pure drug. The in vivo data indicated that the curcumin-loaded SEDDS-treated diabetic rats had significantly faster-wound healing and re-epithelialization compared with the untreated and pure drug-treated groups. Our findings in this work suggest that the curcumin-loaded SEDDS might have great potential in facilitating diabetic wound healing and skin tissue regeneration.

Nanodelivery of essential oils as efficient tools against antimicrobial resistance: a review of the type and physical-chemical properties of the delivery systems and applications

This review provides a synthesis of the last ten years of research on nanodelivery systems used for the delivery of essential oils (EOs), as well as their potential as a viable alternative to antibiotics in human and veterinary therapy. The use of essential oils alone in therapy is not always possible due to several limitations but nanodelivery systems seem to be able to overcome these issues. The choice of the essential oil, as well as the choice of the nanodelivery system influences the therapeutic efficacy obtained. While several studies on the characterization of EOs exist, this review assesses the characteristics of the nanomaterials used for the delivery of essential oils, as well as impact on the functionality of nanodelivered essential oils, and successful applications. Two classes of delivery systems stand out: polymeric nanoparticles (NPs) including chitosan, cellulose, zein, sodium alginate, and poly(lactic-co-glycolic) acid (PLGA), and lipidic NPs including nanostructured lipid carriers, solid lipid NPs, nanoemulsions, liposomes, and niosomes. While the advantages and disadvantages of these delivery systems and information on stability, release, and efficacy of the nanodelivered EOs are covered in the literature as presented in this review, essential information, such as the speed of emergence of a potential bacteria resistance to these new systems, or dosages for each type of infection and for each animal species or humans is still missing today. Therefore, more quantitative and in vivo studies should be conducted before the adoption of EOs loaded NPs as an alternative to antibiotics, where appropriate.

Advancement in Nanoformulations for the Management of Diabetic Wound Healing

People with diabetes have a very slow tendency for wound healing. Wound healing is a vast process where several factors inhibit the sequence of healing. Nano formulation plays a major role during acute and chronic wound healing. The present manuscript aims to discuss the role of nanoformulation in the treatment of diabetic wound healing. Diabetes is a common disease that has harmful consequences which lead to bad health. During the literature survey, it was observed that nanotechnology has significant advantages in the treatment of diabetic wound healing. The present manuscript summarized the role of nanomaterials in wound healing, challenges in diabetic wound healing, physiology of wound healing, a limitation that comes during wound repair, and treatments available for wound healing. After a comprehensive literature survey, it can be concluded that health worker needs more focus on the area of wound healing in diabetic patients. Medical practitioners, pharmaceutical and biomedical researchers need more attention towards the utilization of nanoformulations for the treatment of wound healing, specifically in the case of diabetes.

Advanced drug delivery systems containing herbal components for wound healing

Management of chronic wound has an immense impact on social and economic conditions in the world. Healthcare costs, aging population, physical trauma, and comorbidities of diabetes and obesity seem to be the major factors of this increasing incidence of chronic wounds. Conditions of chronic wound could not restore functional epidermis; thus, delaying the closure of the wound opening in an expected manner. Failures in restoration of skin integrity delay healing due to changes in skin pathology, such as chronic ulceration or nonhealing. The role of different traditional medicines has been explored for use in the healing of cutaneous wounds, where several phytochemicals, such as flavonoids, alkaloids, phenolic acids, tannins are known to provide potential wound healing properties. However, the delivery of plant-based therapeutics could be improved by the novel platform of nanotechnology. Thus, the objectives of novel delivery strategies of principal bioactive from plant sources are to accelerate the wound healing process, avoid wound complications and enhance patient compliance. Therefore, the opportunities of nanotechnology-based drug delivery of natural wound healing therapeutics have been included in the present discussion with special emphasis on nanofibers, vesicular structures, nanoparticles, nanoemulsion, and nanogels.

Mechanism of Propofol-Lidocaine Hydrochloride Nano-Emulsion on Retinal Ganglion Cytopathic Effect in Diabetic Rats

The study drew attention to the influence mechanism of propofol and lidocaine hydrochloride nanoemulsion (NE) in the retinal ganglion cell pathology in diabetic rats. Specifically, the propofollidocaine hydrochloride NE was prepared using the emulsification method. The microscope and laser particle size analyser were used to observe the morphology and particle size of NE, respectively. Also, the viscosity of the NE and the recovery rate of the main ingredient were explored. 45 adult male Wistar rats were randomly divided into control group (PBS control), model group (diabetes model), and test group (diabetes model+propofol-lidocaine hydrochloride NE), with 15 rats in each group. The three groups were compared for the blood glucose, body weight, TNF-α and IL-1β mRNA levels in retinal tissue, and the number and apoptosis rate of ganglion cells. It was found that the average particle size of the NE was 89.76 nm, the maximum absorption wavelength was 280.0 nm, and the viscosity was 106.49 N/m/s. The average recovery rate of propofol in NE was 99.91%, and that of lidocaine hydrochloride was 99.80%. At 12th week after modeling, the blood glucose of the test group was lower versus the model group (P < 0.05); the blood glucose and body weight of rats in the control group were lower than those in the other two groups (P < 0.001). The test group exhibited lower mRNA levels of TNF-α and IL-1β and apoptosis index of retinal ganglion cells versus the model group (P < 0.05). The model group showed a lower number of retinal ganglion cells versus the other two groups (P < 0.05). It was inferred that propofol-lidocaine hydrochloride NE of a small particle size and good syringeability can notably reduce blood glucose, TNF-α and IL-1β mRNA levels, and retinal ganglion cell apoptosis index, and at the same time increase the number of retinal ganglion cells.

Development of Chitosan-Based Nanoemulsion Gel Containing Microbial Secondary Metabolite with Effective Antifungal Activity: In vitro and in vivo Characterizations

Purpose

Microbial resistance to antibiotics is one of the most important public health concerns of the 21^st century. We isolated, purified, and structurally elucidated antifungal secondary metabolites from red soil microbes and encapsulated them into chitosan (CS)-based nanoemulsion (NE) gel (NEG).

Methods

Three compounds were isolated and purified of which only one compound (Pure 2) showed potent antifungal activity (MFC: 8–132 µg/mL), which was also significantly (P<0.05) more efficient than fluconazole (MFC: 32–132 µg/mL). Pure 2 was structurally elucidated using 1D- and 2D-NMR before its incorporation into NEG. The formulations were prepared by high-speed homogenization technique. Physicochemical and pharmacological characterizations of formulations (ie, droplet size, PDI, zeta potential, drug content, viscosity, SEM, FTIR, spreadability, in vitro drug release, ex vivo permeation, in vitro antifungal and in vivo antifungal activities) were assessed.

Results

NMR analyses identified the compound as a derivative of phthalic acid ester (PAE). The optimized formulations displayed a droplet size <100 nm, -ve zeta potential, and PDI <0.45. The drug content was within the official limit of pharmacopeia (ie, 100±10%). Insignificant changes (P>0.05) in the viscosity of the formulations stored were observed. The morphology of the formulations indicated mesh-like structure. The FTIR study indicated that there were no interactions between the drug and other ingredients of the formulations. Optimum spreadability was observed in all formulations. NEG released 75.3±1.12% of Pure 2 after 12 hrs while NE released 85.33±1.88% of the compound. The skin permeation of F2 (71.15±1.28%) was significantly different (P<0.05) from F3 (81.80±1.91%) in rabbits. Complete and apparently safe recovery from the fungal infection was achieved in rabbits treated topically with Pure 2-loaded NEGs.

Conclusion

Hence, the NEG-loaded PAE isolated from Pseudomonas fluorescens represents a possible alternative for the treatment of fungal infections as compared to available therapies.

Hepatoprotective Effects of Bioflavonoid Luteolin Using Self-Nanoemulsifying Drug Delivery System

Luteolin (LUT) is a natural pharmaceutical compound that is weakly water soluble and has low bioavailability when taken orally. As a result, the goal of this research was to create self-nanoemulsifying drug delivery systems (SNEDDS) for LUT in an attempt to improve its in vitro dissolution and hepatoprotective effects, resulting in increased oral bioavailability. Using the aqueous phase titration approach and the creation of pseudo-ternary phase diagrams with Capryol-PGMC (oil phase), Tween-80 (surfactant), and Transcutol-HP (co-emulsifier), various SNEDDS of LUT were generated. SNEDDS were assessed for droplet size, polydispersity index (PDI), zeta potential (ZP), refractive index (RI), and percent of transmittance (percent T) after undergoing several thermodynamic stability and self-nanoemulsification experiments. When compared to LUT suspension, the developed SNEDDS revealed considerable LUT release from all SNEDDS. Droplet size was 40 nm, PDI was <0.3, ZP was -30.58 mV, RI was 1.40, percent T was >98 percent, and drug release profile was >96 percent in optimized SNEDDS of LUT. For in vivo hepatoprotective testing in rats, optimized SNEDDS was chosen. When compared to LUT suspension, hepatoprotective tests showed that optimized LUT SNEDDS had a substantial hepatoprotective impact. The findings of this investigation suggested that SNEDDS could improve bioflavonoid LUT dissolution rate and therapeutic efficacy.

Investigating Antiarthritic Potential of Nanostructured Clove Oil (Syzygium aromaticum) in FCA-Induced Arthritic Rats: Pharmaceutical Action and Delivery Strategies

The combined application of clove oil in a lipid nanocarrier opens a promising avenue for bone and joints therapy. In this study, we successfully developed a tunable controlled-release lipid platform for the efficient delivery of clove oil (CO) for the treatment of rheumatoid arthritis (RA). The ultra-small nanostructured lipid carriers co-loaded with CO (CONCs) were developed through an aqueous titration method followed by microfluidization. The CONCs appeared to be spherical (particle size of 120 nm), stable (zeta potential of −27 mV), and entrapped efficiently (84.5%). In toluene:acetone:glacial acetic acid (90:9:1 percent v/v/v) solvent systems, high-performance thin layer chromatography (HPTLC) analysis revealed the primary components in CO as eugenol (R_F = 0.58). The CONCs greatly increased the therapeutic impact of CO in both in vitro and in vivo biological tests, which was further supported by excellent antiarthritic action. The CONC had an antiarthritic activity that was slightly higher than neat CO and slightly lower than standard, according to our data. The improved formulation inhibited serum lysosomal enzymes and proinflammatory cytokines while also improving hind leg function. This study provides a proof of concept to treat RA with a new strategy utilizing essential oils via nanodelivery.

3D-Printed Products for Topical Skin Applications: From Personalized Dressings to Drug Delivery

3D printing has been widely used for the personalization of therapies and on-demand production of complex pharmaceutical forms. Recently, 3D printing has been explored as a tool for the development of topical dosage forms and wound dressings. Thus, this review aims to present advances related to the use of 3D printing for the development of pharmaceutical and biomedical products for topical skin applications, covering plain dressing and products for the delivery of active ingredients to the skin. Based on the data acquired, the important growth in the number of publications over the last years confirms its interest. The semisolid extrusion technique has been the most reported one, probably because it allows the use of a broad range of polymers, creating the most diverse therapeutic approaches. 3D printing has been an excellent field for customizing dressings, according to individual needs. Studies discussed here imply the use of metals, nanoparticles, drugs, natural compounds and proteins and peptides for the treatment of wound healing, acne, pain relief, and anti-wrinkle, among others. The confluence of 3D printing and topical applications has undeniable advantages, and we would like to encourage the research groups to explore this field to improve the patient's life quality, adherence and treatment efficacy.

Nanoemulsification Improves the Pharmaceutical Properties and Bioactivities of Niaouli Essential Oil (Melaleuca quinquenervia L.)

We develop a suitable delivery system for niaouli essential oil (NEO) using a nanoemulsification method for acne vulgaris. Prepared nanoemulsions (NEs) were characterized for droplet dimension, rheology, surface charge, and stability. The ability of NEO formulations against Propionibacterium acnes and Staphylococcus epidermidis was investigated and all formulations showed antiacne potential in vitro. Ex vivo permeation studies indicated significant improvement in drug permeations and steady state flux of all NEO-NEs compared to the neat NEO (p < 0.05). On the basis of the studied pharmaceutical parameters, enhanced ex vivo skin permeation, and marked effect on acne pathogens, formulation NEO-NE4 was found to be the best (oil (NEO; 10% v/v); Kolliphor EL (9.25% v/v), Carbitol (27.75% v/v), and water (53% v/v)). Concisely, the in vitro and ex vivo results revealed that nanoemulsification improved the delivery as well as bioactivities of NEO significantly.

Essential Oils: Pharmaceutical Applications and Encapsulation Strategies into Lipid-Based Delivery Systems

Essential oils are being studied for more than 60 years, but a growing interest has emerged in the recent decades due to a desire for a rediscovery of natural remedies. Essential oils are known for millennia and, already in prehistoric times, they were used for medicinal and ritual purposes due to their therapeutic properties. Using a variety of methods refined over the centuries, essential oils are extracted from plant raw materials: the choice of the extraction method is decisive, since it determines the type, quantity, and stereochemical structure of the essential oil molecules. To these components belong all properties that make essential oils so interesting for pharmaceutical uses; the most investigated ones are antioxidant, anti-inflammatory, antimicrobial, wound-healing, and anxiolytic activities. However, the main limitations to their use are their hydrophobicity, instability, high volatility, and risk of toxicity. A successful strategy to overcome these limitations is the encapsulation within delivery systems, which enable the increase of essential oils bioavailability and improve their chemical stability, while reducing their volatility and toxicity. Among all the suitable platforms, our review focused on the lipid-based ones, in particular micro- and nanoemulsions, liposomes, solid lipid nanoparticles, and nanostructured lipid carriers.

Julbernardia paniculata and Pterocarpus angolensis: From Ethnobotanical Surveys to Phytochemical Characterization and Bioactivities Evaluation

Julbernardia paniculata and Pterocarpus angolensis are two plant species with important application in African traditional medicine, particularly in Angola, in the treatment of several diseases. However, scientific studies concerning these species are scarce. The goal of this work was to know better which medicinal approaches are used by the Huíla population in Angola by means of ethnobotanical surveys. Furthermore, extracts of both plants were phytochemically characterized. Antioxidant, anti-inflammatory, wound-healing activities, and potential cytotoxicity were also studied. With this study it was possible to verify that 67% of the individuals that use medicinal plants are women, and their main therapeutic uses are the treatment of problems of the digestive system and skin disorders. Barks of J. paniculata and leaves of P. angolensis are the most often used plant parts. Through high-performance liquid chromatography coupled to diode-array detector (HPLC-DAD) and GC-MS it was possible to characterize the chemical composition of the two species, which are rich in phenolic compounds, terpenes, terpenoids, sesquiterpenoids and fatty acids. Both plants showed to possess antioxidant, anti-inflammatory proprieties, and wound-healing activity. To the best of our knowledge, this is the most comprehensive study of these two species and the first ethnobotanical and ethnopharmacological study of medicinal plants from this region of Angola.

Deep skin wound healing potential of lavender essential oil and licorice extract in a nanoemulsion form: Biochemical, histopathological and gene expression evidences

Cutaneous wound healing is one of the public health interests. This study aimed to investigate the effects of nanoemulsion cream containing lavender essential oil and licorice extract on the healing of deep skin wound in a rat model. Eighty-five male Wistar rats were randomly divided into five groups including untreated defects as negative control and defects treated with vehicle ointment, lavender essential oil and licorice extract in emulsion and nanoemulsion forms, and phenytoin 1% as the positive control with an excisional wound on the dorsal neck of each rat. On days 2, 7 and 14 oxidative stress factors were evaluated in wound tissue homogenates. The expression of transforming growth factor-β (TGF-β), and type I and type III collagen genes were evaluated. Also, wound tissue samples were processed for Hematoxylin & Eosin and Masson-Trichrome staining. Nanoemulsion reduced the wound area more than other groups significantly. Real-time PCR data demonstrated that nanoemulsion and phenytoin groups have shown the best result in increasing TGF-β1, Type I and type III collagen genes expression compared to the other groups. Reduction in lipid peroxidation level and increasing in SOD and GPx activity was also significant in the nanoemulsion and phenytoin groups. The formation of granular tissue likewise the appearance of collagen in nanoemulsion and phenytoin groups were faster than the other groups. Nanoemulsion cream containing lavender essential oil and licorice extract exhibited a promising wound healing potential towards the excisional wound model in rats.

A novel self-nanoemulsifying drug delivery system for curcumin used in the treatment of wound healing and inflammation

The main objective of this study was to develop and evaluate self-nanoemulsifying drug delivery system (SNEDDS) of curcumin (Cur) to enhance their solubility as well as improve skin permeation; and evaluate wound healing potential of Cur via SNEDDS in comparison with standards pure eucalyptus oil-SNEDDS (Euc-SNEDDS), pure curcumin suspension (Cur-S), and standard fusidic acid followed by their anti-inflammatory action. Curcumin-loaded different SNEDDS formulations were formulated through aqueous phase titration method and the zones of SNEDDS were recognized by the construction of phase diagrams. Eucalyptus oil, Tween 80 (surfactant), and Transcutol HP (co-surfactant) were selected on the basis of their solubility and highest nanoemulsion region. Characterization of thermodynamic stability for Cur-loaded SNEDDS was evaluated by its globule size, zeta potential, polydispersity index, viscosity, % transmittance, refractive index, and surface morphology. Cur-SNEDDS (Cur-SN4) was optimized and selected on the basis of their excellent physicochemical parameters for in vivo activity. The particle size (59.56 ± 0.94 nm), % transmittance (99.08 ± 0.07%), and PDI (0.207 ± 0.011 were observed for optimized Cur-SNEDDS. TEM and SEM showed their smooth and spherical shape of the morphological characterization with zeta potential (- 21.41 ± 0.89), refractive index (1.341 ± 0.06), and viscosity (11.64 ± 1.26 cp) for optimized Cur-SNEDDS. Finally, optimized Cur-SNEDDS was used to enhance skin permeation with improvement in the solubility of Cur. However, optimized Cur-SNEDDS showed significant wound healing activity as compared with pure eucalyptus oil and Cur-S on topical application. Optimized Cur-SNEDDS showed healing of wound as compared to standard fusidic acid. Optimized Cur-SNEDDS exhibited no signs of inflammatory cells on the histopathological studies of treated rats which were recommended the safety and non-toxicity of Cur-SNEDDS. Newly developed Cur-SNEDDS could be successfully used to enhance Cur-solubility and skin permeation, as well as suggested a potential role of Cur-SNEDDS for better improvement of wound healing activity followed by anti-inflammatory action of Cur via topical application.

Phytomedicines containing Matricaria species for the treatment of skin diseases: A biotechnological approach

Skin diseases have a notable impact on the life of the affected and in their health conditions. In order to allow a more effective and economical treatment for such disorders, new therapeutic approaches have been continuously investigated. Due to its high therapeutic and phytochemical potential, Matricaria species emerges as a pleasant alternative, since it is an important source of bioactive secondary metabolites suitable for the treatment of varied skin diseases. Therefore, this review aimed to catalog inventions that have used Matricaria species as the active component for skin disease treatment in order to assess the status of the technological development of the fitomedicines. For this, a search of patents was performed in four specialized patent database, which have reported the discovery of pharmaceutical bioproducts that used Matricaria species in its composition for skin treatment. Therefore, it is possible to notice that the pharmaceutical industry has driven efforts and investment to produce medicines for the dermatopathies, using species of this genus as an active principle. Besides, a trend of growth has been identified for the last years, which is accompanied by the continuous publication of scientific articles on the subject. It is known that a long journey is traversed between the scientific findings and their applications in the pharmaceutical market, creating the perspective that new Matricaria-based medicines may reach the pharmaceutical market in the coming years.

Wound healing evaluation of self-nanoemulsifying drug delivery system containing Piper cubeba essential oil

The objective of this work was to characterize and evaluate wound healing potential of Piper cubeba oil (PO) via self-nanoemulsifying drug delivery system (SNEDDS) in comparison with standard gentamycin. PO loaded SNEDDS was prepared by low energy emulsification technique and characterized for thermodynamic stability, self-emulsification power and various physico-chemical parameters. An optimal formula of PO SNEDDS was subjected to wound healing evaluation, collagen determination and histomorphological examination in female Wistar rats as compared with pure PO and standard antibiotic/gentamycin. An optimal formula of PO SNEDDS showed significant wound healing effects in Wistar female rats in comparison with pure PO. However, wound healing effects of optimized SNEDDS were comparable with standard gentamycin. An optimized formulation also indicated significant enhancement in collagen content (0.82 mg/g) in comparison with pure PO (0.53 mg/g) and negative control (0.33 mg/g). While, the collagen content of SNEDDS (0.82 mg/g) treated rats were comparable with standard gentamycin treated animals (0.98 mg/g). Histopathological examinations of optimized SNEDDS treated animals showed no signs of inflammatory cells which indicated that prepared SNEDDS was safe and nontoxic to rats. The results obtained in this work showed the potential application of SNEDDS in enhancement of the wound healing activity of PO upon oral administration.