Use of fruit epicarps to formulate pectin-based bioactive films / Utilização de epicarpos de frutos para formulação de filmes bioativos à base de pectinas

The functional properties of biofilms can vary according to the biopolymer used as the raw material; thus, in the search for alternative sources for preparation of biodegradable films, fruits and vegetables have been used to extract compounds of interest with applications in the food industry. The objective of this work was to obtain and characterize bioactive films based on pectin extracted from the epicarps (skin) of the fruit. The genipap (Genipa americana), red pitaya (Hylocereus polyrhizus) and star fruit (Averrhoa carambola) were collected, washed, pulped and dried at 50 °C for 24 h, and their epicarps were ground and subjected to pectin extraction using the casting method. The films were characterized as to their visual appearance, moisture, pH, water solubility and antioxidant activity. The pectin-based films of G. americana and H. polyrhizus showed a yellowish color, while A. carambola was dark brown. The highest pectin yield (29%) and moisture content (13.9%) were obtained from the H. polyrhizus film, while A. carambola showed the highest solubility in water (98.6%) and had the highest pH (3.9). Additionally, the film based on A. carambola showed greater antioxidant potential against ABTS (30.5%) and DPPH (34%), as well as greater reducing power (0.262 absorbance at 750 nm) and content of total phenolic compounds (553 mg GAE/100 g), whereas H. polyrhizus had a higher percentage of chelating ability (27%). The physicochemical characteristics and bioactive properties exhibited make the film formulation a viable alternative for the food industry.

Bioactive Pectin-Murta (Ugni molinae T.) Seed Extract Films Reinforced with Chitin Fibers

This study investigated the biocomposite pectin films enriched with murta (Ugni molinae T.) seed polyphenolic extract and reinforced by chitin nanofiber. The structural, morphological, mechanical, barrier, colorimetric, and antioxidant activity of films were evaluated. The obtained data clearly demonstrated that the addition of murta seed extract and the high load of chitin nanofibers (50%) provided more cohesive and dense morphology of films and improved the mechanical resistance and water vapor barrier in comparison to the control pectin film. The antioxidant activity ranged between 71% and 86%, depending on the film formulation and concentration of chitin nanofibers. The presented results highlight the potential use of chitin nanofibers and murta seed extract in the pectin matrix to be applied in functional food coatings and packaging, as a sustainable solution.

Trimetazidine Topical Delivery Prevents Carrageenan Induced Retinal Damage and Glucose Induced Lens Opacification by Decreasing Drop of Protein Level

Carrageenan induced oxidative stress develops retinal damage and increases lipid peroxidation. Glycation of the lens proteins increases modified proteins and may affect the lens structural integrity and opacification, after increasing glucose concentration in the lens. Trimetazidine (TZ) has been reported to have cytoprotective anti-ischaemic activity after systemic administration in an animal model. Trimetazidine ophthalmic film formulation has been prepared using HPMC as the hydrogel-forming polymer. The cytoprotective role of trimetazidine has been studied on carrageenan-induced retinal damage of rat eye by histologicaland Malondialdehyde (MDA) assay applying sterilized film formulation. Trimetazidine solution was used in combination with a high concentration of glucose solution (55 mM) for examining the protective effect from cataract formation. Formulation showed controlled and extended ophthalmic permeation of the drug for about 5 h. Damage of retinal cells in the ganglionic layer has been decreased significantly in the trimetazidinetreated group. Drug treated control group also showed significant disappearance of pyknotic cells. The addition of trimetazidine to the glucose medium practically retarded the lens opacification by reducing the over-production of reactive oxygen species (ROS) in increased sugar concentration. Presence of trimetazidine probably decreased the drop of protein level in lens under stressed condition and greater preventive effect has been noticed with TZ concentration of 240 µg/ml rather than 120 µg/ml. Trimetazidine ophthalmic film formulation could prevent retinal damage and cataract formation.

Vildagliptin plasticized hydrogel film in the control of ocular inflammation after topical application: study of hydration and erosion behaviour

Vildagliptin (VID) is a dipeptidyl peptidase-4 (DPP-4) inhibitor used in controlling blood glucose level in type 2 diabetes. Vildagliptin improves beta cells function and is also suggested to effectively control the inflammation. The possible ocular anti-inflammatory property of vildagliptin has been explored using topically applied plasticized ocular film formulation. Film formulation was prepared by solvent cast and evaporation method using triethanolamine (TEA), dimethyl sulphoxide (DMSO), and polyethylene glycol 400 (PEG 400) as the plasticizer in HPMC hydrogel matrix base. Anti-inflammatory study was carried out in the carrageenan induced ocular rabbit model. Analytical methods confirmed that the drug was present almost in completely amorphized form in the film formulation. Level of hydration, swelling and erosion rate of the film played the controlling factor in the process of drug release, ocular residence and permeation. Maximum swelling rate of 363 h−1 has been shown by VHT compared to other formulation of VHD and VHP (174 and 242 h−1 respectively). Film containing DMSO exhibited highest in vitro release as well as ex vivo ocular permeation. Film formulation has shown a fast recovery of ocular inflammation in contrast to the untreated eye after inducing inflammation. Plasticized vildagliptin hydrogel film formulation could be utilized in the management and control of ocular inflammation particularly with diabetic retinopathy after proper clinical studies in higher animal and human individuals.