Ethosomes-based gel formulation of karanjin for treatment of acne vulgaris: in vitro investigations and preclinical assessment

The aim of the present study was to develop and characterize karanjin-loaded ethosomes-based gel formulation for enhanced topical delivery and effective therapy of skin acne. Karanjin-loaded ethosomes (K-ETH) presented a nanometric size of 140.87 ± 2.35 nm, entrapment of 71.41 ± 2.74% and enhanced permeation with 1.9 times increase in the flux and 2.4 times higher skin deposition compared to the hydro-ethanolic solution of karanjin. The DSC analysis confirmed successful entrapment of the karanjin within the ethosomes. The developed ethosomes were incorporated in the carbopol gel for adequate application on the skin surface. The ethosomal gel (K-EGF) also exhibited greater penetration in the rat skin as revealed by CLSM. The optimized K-EGF formulation was non-irritant to the skin as evident by Draize score test and histopathological examination. The highest zone of inhibition, 30.0 ± 1.52 mm and 36.22 ± 0.57 mm was produced by the K-EGF against Propionibacterium acnes and Staphylococcus epidermidis, respectively, indicating substantial antibacterial properties of the K-EGF. DPPH assay indicated its potent antioxidant effects. Substantial anti-inflammatory effects in the carrageenan-induced edema in the rat paw were evident with inhibition of rat paw edema by 66.66% and 70.37% upon application of K-EGF and standard anti-inflammatory agent, respectively. Anti-acne effects were also evident with K-EGF treatment with significant decrease in number and size of sebaceous gland units in dermis. Overall, the above findings vouch for a therapeutic opportunity to improve topical delivery of karanjin in acne treatment employing ethosomal gels as the promising carrier system.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13205-021-02978-3.

Free radical scavenging and anti-acne activities of mangosteen fruit rind extracts prepared by different extraction methods

The ethanol extracts of mangosteen fruit rinds prepared by several extraction methods were examined for their contents of bioactive compounds, DPPH-scavenging activity, and anti-acne producing bacteria against Propionibacterium acnes and Staphylococcus epidermidis. The dried powder of the fruit rind was extracted with 95% ethanol by maceration, percolation, Soxhlet extraction, ultrasonic extraction, and extraction using a magnetic stirrer. Soxhlet extraction promoted the maximum contents of crude extract (26.60% dry weight) and alpha-mangostin (13.51%, w/w of crude extract), and also gave the highest anti-acne activity with MIC 7.81 and 15.63 microg/mL and MBC 15.53 and 31.25 microg/mL against P. acnes and S. epidermidis, respectively. Ethanol 70% and 50% (v/v) were also compared in Soxhlet extraction. Ethanol 50% promoted the extract with maximum amounts of total phenolic compounds (26.96 g gallic acid equivalents/100 g extract) and total tannins (46.83 g tannic acid equivalents/100 g extract), and also exhibited the most effective DPPH-scavenging activity (EC(50) 12.84 microg/mL). Considering various factors involved in the process, Soxhlet extraction carried a low cost in terms of reagents and extraction time. It appears to be the recommended extraction method for mangosteen fruit rind. Ethanol 50% should be the appropriate solvent for extracting free radical-scavenging components, phenolic compounds, and tannins, while 95% ethanol is recommended for extraction of alpha-mangostin, a major anti-acne component from this plant.

A review of phytotherapy of Acne vulgaris

Acne vulgaris (acne) is a cutaneous pleomorphic disorder of the pilosebaceous unit involving abnormalities in sebum production and is characterized by both inflammatory (papules, pustules and nodules) and non-inflammatory (comedones, open and closed) lesions. Propionibacterium acnes and Staphylococcus epidermidis are common pus-forming microbes responsible for the development of various forms of acne. This disease remains a common condition in industrialized societies, with many mainstream treatment options available. There are many acne products on the market, and making an appropriate selection can be daunting. Common therapies that are used for the treatment of acne include topical, systemic, hormonal, herbal and combination therapy. Topically used agents are benzoyl peroxide, antibiotics and retinoid. Systemically used agents are antibiotics and isotretinoin. However, all such treatments carry risks and none is completely satisfactory. Natural alternatives are gaining greater research support, and have much to offer clinically in this disorder. This review focuses primarily on herbal treatments for acne that show scientific evidence of clinical efficacy, as well as the more common herbs shown to be useful in the treatment of this dermatologic disorder.