Phenolic compounds as well as flavonoids are well-known as antioxidant and many other important bioactive agents that have long been interested due to their benefits for human health, curing and preventing many diseases. This review attempts to demonstrate an overview of flavonoids and other phenolic compounds as the interesting alternative sources for pharmaceutical and medicinal applications. The examples of these phytochemicals from several medicinal plants are also illustrated, and their potential applications in pharmaceutical and medical aspects, especially for health promoting e.g., antioxidant effects, antibacterial effect, anti-cancer effect, cardioprotective effects, immune system promoting and anti-inflammatory effects, skin protective effect from UV radiation and so forth are highlighted.

https://www.mdpi.com/2305-6320/5/3/93/pdf

Flavonoids and Other Phenolic Compounds from Medicinal Plants for Pharmaceutical and Medical Aspects: An Overview.

Chitosan as a bioactive polymer: Processing, properties and applications.

Carboxymethyl chitosan: Properties and biomedical applications.

Chitosan is a biopolymer obtained from chitin, one of the most abundant and renewable materials on Earth Chitin is a primary component of cell walls in fungi, the exoskeletons of arthropods such as crustaceans, eg, crabs, lobsters and shrimps, and insects, the radulae of molluscs, cephalopod beaks, and the scales of fish and lissamphibians The discovery of chitin in 1811 is attributed to Henri Braconnot while the history of chitosan dates back to 1859 with the work of Charles Rouget The name of chitosan was, however, introduced in 1894 by Felix Hoppe-Seyler Chitosan has attracted major scientific and industrial interests from the late 1970s due to its particular macromolecular structure, biocompatibility, biodegradability and other intrinsic functional properties Chitosan and derivatives have practical applications in the food industry, agriculture, pharmacy, medicine, cosmetology, textile and paper industries, and in chemistry In recent years, chitosan has also received much attention in dentistry, ophthalmology, biomedicine and bioimaging, hygiene and personal care, veterinary medicine, packaging industry, agrochemistry, aquaculture, functional textiles and cosmetotextiles, catalysis, chromatography, beverage industry, photography, wastewater treatment and sludge dewatering, and biotechnology Nutraceuticals and cosmeceuticals are actually growing markets, and therapeutic and biomedical products should be the next markets in the development of chitosan Chitosan is also the object of numerous fundamental studies In this review, we highlight a selection of works on chitosan applications published over the past two decades

https://hal.archives-ouvertes.fr/hal-02402948/document

Applications of chitosan in food, pharmaceuticals, medicine, cosmetics, agriculture, textiles, pulp and paper, biotechnology, and environmental chemistry

Hydrogel scaffolds serve as semi synthetic or synthetic extra cellular matrix to provide an amenable environment for cellular adherence and cellular remodeling in three dimensional structures mimicking that of natural cellular environment. Additionally, hydrogels have the capacity to carry small molecule drugs and/or proteins, growth factors and other necessary components for cell growth and differentiation. In the context of drug delivery, hydrogels can be utilized to localize drugs, increase drugs concentration at the site of action and consequently reduce off-targeted side effects. The current review aims to describe and classify hydrogels and their methods of production. The main highlight is chitosan-based hydrogels as biocompatible and medically relevant hydrogels for drug delivery.

http://www.rps.mui.ac.ir/index.php/jrps/article/download/1611/1561

Chitosan based hydrogels: characteristics and pharmaceutical applications.

The rise in solar ultraviolet radiation on the earth's surface has led to a depletion of stratospheric ozone over recent decades, thus accelerating the need to protect human skin against the harmful effects of UV radiation such as erythema, edema, hyperpigmentation, photoaging, and skin cancer. There are many different ways to protect skin against UV radiation's harmful effects. The most popular way to reduce the amount of UV radiation penetrating the skin is topical application of sunscreen products that contain UV absorbing or reflecting active molecules. Based on their protection mechanism, the active molecules in sunscreens are broadly divided into inorganic and organic agents. Inorganic sunscreens reflect and scatter UV and visible radiation, while organic sunscreens absorb UV radiation and then re-emit energy as heat or light. These synthetic molecules have limited concentration according to regulation concern. Several natural compounds with UV absorption property have been used to substitute for or to reduce the quantity of synthetic sunscreen agents. In addition to UV absorption property, most natural compounds were found to act as antioxidants, anti-inflammatory, and immunomodulatory agents, which provide further protection against the damaging effects of UV radiation exposure. Compounds derived from natural sources have gained considerable attention for use in sunscreen products and have bolstered the market trend toward natural cosmetics. This adds to the importance of there being a wide selection of active molecules in sunscreen formulations. This paper summarizes a number of natural products derived from propolis, plants, algae, and lichens that have shown potential photoprotection properties against UV radiation exposure-induced skin damage.

Natural products as photoprotection

Carboxymethyl chitosan is a chitosan derivative of the most intensively investigated due to its water solubility in wider pH range compared with the parent compound, thus extended its use in various applications. In this review, different preparation conditions, which resulting in the N- and O-carboxylated chitosan, diverse degree of substitution and water solubility are recapitulated. Five important features of carboxymethyl chitosan from recent studies, which are moisture absorption-retention, anti-microbial properties, antioxidant capacities, delivery system and emulsion stabilization, have been centred and emphasized for cosmetic utilization. Additionally, cytotoxicity information has been inclusively incorporated to ensure its safety in application.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/ics.12102

Utilization of carboxymethyl chitosan in cosmetics.

Article history: Received on: 28/07/2013 Revised on: 07/08/2013 Accepted on: 25/08/2013 Available online: 30/09/2013 Overexposure to ultraviolet (UV) radiation can cause a number of skin disorders such as erythema, edema, hyperpigmentation, immunosuppression, photoaging, and skin cancer. Since the level of UV radiation is increasing as a result of depletion of the stratospheric ozone and climate change, the protection of human skin against the harmful effects of UV radiation is an urgent need. Topical application of sunscreens is a strategy to protect the deleterious effect of UV radiation on the skin. Sunscreens today contain one or several synthetic UV filter molecules which protect the UV radiation exposed on the epidermis. These molecules are broadly divided into physical and chemical agents. Physical sunscreens reflect and scatter UVB, UVA and visible radiation. Chemical sunscreens act by absorbing ultraviolet radiation and re-emitting chemical energy as heat or light. Several synthetic UV filter molecules are available in the market but they have limited use because these active molecules may create adverse effects on human skin. Some information on possible photon induced reaction such as photoirritation, photosensitization and contact dermatitis by sunscreen products containing synthetic organic sunscreen agents. To overcome these side effects, naturally occurring compounds have gained considerable attention as photoprotective agents. Flavonoids, a group of natural occurring compounds, act as catalysts in the light phase of photosynthesis and as stress protectants in plant cells by scavenging reactive oxygen species (ROS). Natural flavonoids have the potential photoprotection because of their UV absorbing, their ability to act as direct and indirect antioxidants as well as anti-inflammatory and immunomodulatory agents which provide exciting platforms for the development of photoprotection. This review summarizes the structure and potential photoprotection activity of several natural flavonoids.

/pdf/photoprotection-of-natural-flavonoids-48fdem145w.pdf

Photoprotection of natural flavonoids

Objective To determine hydrophilic–lipophilic balance (HLB) value, stability of formulate emulsion and properties of sacha inchi oil. Methods The physiochemical characteristics of sacha inchi oil were first investigated. Free radical scavenging property was studied by DPPH assay. HLB value of sacha inchi oil was experimentally determined by preparing the emulsion using emulsifiers at different HLB value. Sacha inchi oil emulsion was prepared using the obtained HLB and its stability was conducted by centrifugation, temperature cycling, and accelerated stability test. The efficiency of the prepared emulsion was clinically investigated by 15 volunteers. The primary skin irritation was performed using closed patch test. Subjective sensory assessment was evaluated by using 5-point hedonic scale method. Results Peroxide value of sacha inchi oil was 18.40 meq O2/kg oil and acid value was 1.86 KOH/g oil. The major fatty acids are omega-3 (44%), omega-6 (35%) and omega-9 (9%). The vitamin E content was 226 mg/100 g oil. Moreover, sacha inchi oil (167 ppm) and its emulsion showed 85% and 89% DPPH inhibition, respectively. The experimental HLB value of sacha inchi oil was 8.5. The sacha inchi oil emulsion exhibited good stability after stability test. The emulsion was classified as non-irritant after tested by primary skin irritation method. The skin hydration value significantly increased from 38.59 to 45.21 (P  Conclusions This work provides information on HLB value and emulsion properties of sacha inchi oil which is useful for cosmetic and pharmaceutical application.

Determination of hydrophilic–lipophilic balance value and emulsion properties of sacha inchi oil

Purpose : To develop Thai pandan (Pandanus amaryllifolius) as an antioxidant ingredient for topical emulsion. Methods : Dried leaf and root of P. amaryllifolius (Pandanceae) were extracted separately by maceration with either ethanol or propylene glycol. Antioxidant capacity was investigated by 2,2-diphenyl-1-picry hydrazyl radical (DPPH) and linoleic acid peroxidation method. The total phenolic content was measured by Folin-Ciocalteau assay. Oil-in-water topical emulsions containing the individual extracts were prepared and tested for stability. Results : Propylene glycol extract exhibited higher DPPH activity and total phenolic content than the ethanol extract while the DPPH activity of the leaf extract was higher than that of the root. The 50 % inhibition concentration (IC50) value of leaf and root extracts was 0.810 and 2.340 mg/ml, respectively. Although the antioxidant activity of the crude extracts was lower than that of standard vitamin C and butylated hydroxytoluene (BHT), the ethanol/propylene glycol solution extract (ethanol was reduced to 50 % extract volume) showed higher inhibition (90.1 %) of linoleic acid peroxidation than 200 ppm of vitamin C (57.1 %) and BHT (71.1 %). An oil-in-water emulsion containing 3 % of the ethanol and propylene glycol extract showed creamy texture with medium viscosity and demonstrated good stability under accelerated aging test. Conclusion : The results indicate a potential for the development of P. amaryllifolius leaf extract as an antioxidant ingredient in topically applied formulations. Keywords : Pandanus amaryllifolius, Extraction, Antioxidant, Emulsion, Stability.

/pdf/antioxidant-activity-of-pandanus-amaryllifolius-leaf-and-4j6cn708jo.pdf

Ampa Jimtaisong

Papers

Natural products as photoprotection

Utilization of carboxymethyl chitosan in cosmetics.

Photoprotection of natural flavonoids

Determination of hydrophilic–lipophilic balance value and emulsion properties of sacha inchi oil

Antioxidant Activity of Pandanus amaryllifolius Leaf and Root Extract and its Application in Topical Emulsion