Potential of quercetin in combination with antioxidants of different polarity incorporated in oil-in-water nanoemulsions to control enzymatic browning of apples

Leishmaniasis is one of the most neglected diseases in the world. Its most severe clinical form, called visceral, if left untreated, can be fatal. Conventional therapy is based on the use of pentavalent antimonials and includes amphotericin B (AmB) as a second-choice drug. The micellar formulation of AmB, although effective, is associated with acute and chronic toxicity. Commercially-available lipid formulations emerged to overcome such drawbacks, but their high cost limits their widespread use. Drug delivery systems such as nanoemulsions (NE) have proven ability to solubilize hydrophobic compounds, improve absorption and bioavailability, increase efficacy and reduce toxicity of encapsulated drugs. NE become even more attractive because they are inexpensive and easy to prepare. The aim of this work was to incorporate AmB in NE prepared by sonicating a mixture of surfactants, Kolliphor® HS15 (KHS15) and Brij® 52, and an oil, isopropyl myristate. NE exhibited neutral pH, conductivity values consistent with oil in water systems, spherical structures with negative Zeta potential value, monomodal size distribution and average diameter of drug-containing droplets ranging from 33 to 132 nm. AmB did not modify the thermal behavior of the system, likely due to its dispersion in the internal phase. Statistically similar antileishmanial activity of AmB-loaded NE to that of AmB micellar formulation suggests further exploring them in terms of toxicity and effectiveness against amastigotes, with the aim of offering an alternative to treat visceral leishmaniasis.

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Natural Tyrosinase Inhibitors: Role of Herbals in the Treatment of Hyperpigmentary Disorders

Mini-Reviews in Medicinal Chemistry ◽

10.2174/1389557519666190116101039 ◽

2019 ◽

Vol 19 (10) ◽

pp. 796-808 ◽

Cited By ~ 6

Author(s):

Kamal Uddin Zaidi ◽

Sharique A. Ali ◽

Ayesha Ali ◽

Ishrat Naaz

Keyword(s):

Critical Role ◽

Enzymatic Browning ◽

Melanin Production ◽

Natural Sources ◽

Pigmentary Disorders ◽

Normal Manner ◽

Abnormal Accumulation ◽

Current Article ◽

Tyrosinase Inhibitors

Cutaneous pigmentation plays critical role in determining the color of skin along with photo protection of skin from dreadful effects of ultraviolet radiations. Conversely, abnormal accumulation of melanin is responsible for hyper pigmentary disorders such as melasma, senile lentigines and freckles. Because of the visible nature of dermatologic diseases, they have a considerable psychosomatic effect on affected patients. Tyrosinase inhibitors are molecules that interrelate in some way with the enzyme to prevent it from working in the normal manner. Past many decades witnessed the quest for the development of natural tyrosinase inhibitors due to imperative role played by tyrosinase in the process of melanogenesis and fungi or fruit enzymatic browning. Mechanism of pigmentation is characterized by the intact process of the synthesis of specialized black pigment within melanosomes. Melanin is synthesized by a cascade of enzymatic and chemical reactions. For this reason, melanin production is mainly controlled by the expression and activation of tyrosinase. In the current article, we discussed tyrosinase inhibitors from the natural sources, which can be an essential constituent of cosmetics products and depigmenting agents for the treatment of hyperpigmentory disorders.

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Nanoemulsions- A better Approach for Anti Diabeticdrugs Delivering

Current Diabetes Reviews ◽

10.2174/1573399817666201209095205 ◽

2020 ◽

Vol 17 ◽

Author(s):

V. Manimaran ◽

Ponnurengam Malliappan Sivakumar ◽

J. Narayanan ◽

Shanmugam Parthasarathi ◽

Pranav Kumar Prabhakar

Keyword(s):

Aqueous Phase ◽

Therapeutic Agent ◽

Antidiabetic Drugs ◽

Optical Behaviour ◽

Antimicrobial Drugs ◽

Drug Degradation ◽

Oil In Water ◽

Drug Technology ◽

Human Use ◽

Poor Absorption

: Conventional delivery of antidiabetic drugs faces many problems like poor absorption, low bioavailability, and drug degradation. Nanoemulsion is a unique drug technology which is very suitable for the delivery of antidiabetic drugs. In recent years the flaws of delivering anti-hypoglycaemic drugs have been overcome by choosing nanoemulsion drug technology. They are thermodynamically stable and also deliver the therapeutic agent for a longer duration. Generally, Nanoemulsions are made up of either oil-in-water or water-in-oil and size of the droplets is from fifty to thousand nanometer. Surfactants are critical substances which are added in the manufacturing of nanoemulsions. Only the surfactants which are approved for human use can be utilized in the manufacturing of nanoemulsions. Generally, the preparation of emulsions includes mixing of the aqueous phase and organic phase and using surfactant with proper agitation. Nanoemulsions are used for antimicrobial drugs, and they are also used in the prophylaxis of cancer, diabetics. Reduction in the droplet size may cause variation in the elastic and optical behaviour of nanoemulsions.

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Plant Oil-Based Nanoemulsions: Preparation and Efficacy for Hair Treatment

Current Applied Polymer Science ◽

10.2174/2452271604999201026191844 ◽

2020 ◽

Vol 04 ◽

Author(s):

Lívia Gonçalves Ferreira Rodrigues ◽

Juliana Falcão Alves de Carvalho ◽

Cristal dos Santos Cerqueira Pinto ◽

Elisabete Pereira Santos ◽

Claudia Regina Elias Mansur

Keyword(s):

Human Hair ◽

Mechanical Tests ◽

Plant Oils ◽

Plant Oil ◽

Oil In Water ◽

Hair Samples ◽

Poly Ethylene Oxide ◽

Treatment Objective ◽

Poly Ethylene ◽

Average Size

Background:: The use of polymers in hair care products is widespread, and silicones in particular are extensively used in cosmetic formulations. In addition, plant oils can also be used for hair treatment. Objective: In the present work, oil-in-water (O/W) nanoemulsions were prepared to repair chemical damage to human hair samples, to investigate the combined use of a silicone polyether copolymer (surfactant) that has a branch composed of poly(ethylene oxide) in its chains, and two types of plant oils: coconut and ojon oil. Materials and Methods:: Surfactant-oil-water formulations were obtained by ultrasonic processing. The nanoemulsions were then applied to human hair strands previously damaged with sodium hydroxide, to compare the treated strands with untreated ones. The efficacy of the formulations was investigated by scanning electron microscopy, thermogravimetric analysis and mechanical tests. Results and Discussion:: Stables nanoemulsions were obtained with average size of the dispersed droplets up to 400 nm. The micrographs suggest that the action mechanism of the nanoemulsions depends not only on the type of plant oil used and size of the droplets dispersed in the system, but also on the type of hair that receives the treatment. The thermal analysis showed that the use of nanoemulsion changed the temperature of keratin interconversion to higher values, which can make hair fibers more resistant to heat. Hair resistance was improved when comparing virgin samples to the damaged ones. Conclusion:: The nanoemulsions were efficient in the treatment of the hair samples, which showed a significant improvement of their mechanical properties.

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