Processing and stabilization of Aloe Vera leaf gel by adding chemical and natural preservatives

Background and objectives: Aloe vera has been used as a medicinal herb for thousands of years. Aloe vera leaves can be separated into latex and gel which have biological effects. Aloe gel is a potent source of polysaccharides. When the gel is exposed to air, it quickly decomposes and decays and loses most of its biological activity. There are various processing techniques for sterilizing and stabilizing the gel. The aim of this study was to improve stabilization of the gel by adding some chemical and natural preservatives. Methods: The gel was obtained from Aloe vera leaves and after some processing chemical and natural preservatives were added. Chemicals included citric acid, ascorbic acid, vitamin E and potassium sorbate while natural preservatives were two essential oils derived from Cinnamomum zeylanicum and Eugenia caryophyllata. All these operations were performed under sterile conditions and they were evaluated at different temperatures and times. Appearance and taste changes of gel were studied organoleptic. Microbiological tests and some physical assays such as pH, refractometry and viscosity properties as well as determination of total sugars were measured. NMR and FT-IR analyses were performed for determining the quality of samples. Results: After data analyzing, the results showed that the samples formulated with chemical additives together with essential oils were more suitable and stable compared to the control samples after 90 days and the effective ingredient acemannan, remained stable. Conclusion: The stable gel can be considered for therapeutic properties and be used for edible and medicinal purposes

Encapsulation of thyme essential oil in polymeric capsules using electrospray method

Background and objectives: Essential oils (EOs) of medicinal herbs are prone to degradation by oxidation, heating, or light. Encapsulation of EOs can protect these fragile volatile natural products from degradation. Thymus vulgaris (thyme) is a well-known herb which has been used as food additive as well as medicine since ancient times. Electrospraying is a novel technology to encapsulate food and pharmaceutical materials. The aim of this study was to apply electrospray method for encapsulation of thyme essential oil in polymeric capsules. Methods: The thyme essential oil was obtained by hydrodistillation. Ploylactic acid (PLA) capsules, loaded by thyme EO, were synthesized by electrospraying. The applied voltage was set at 18 kV and the flow rate of solution in injector was 0.5 mL/h. Polymethyl methacrylate (PMMA) capsules were also prepared. The distance between metal nozzle and collector plate was 25 cm. The solution was injected at the flow rate of 0.5 mL/h and the applied voltage was set at 8 kV. SEM micrographs of the produced micro/nanocapsules were analyzed using image j software. Results: The findings indicated that the mean diameter of PLA capsules were about 162 nm while in the case of PMMA capsules, the mean diameter of fabricated particles was about 5.4 µm. Conclusion: The major conclusion of this study was that the particle size and morphology of synthesized particle was directly affected by the type of polymer utilized for electrospraying

In vitro wound healing activity of luteolin

Background and objectives: Luteolin (3′,4′,5,7-tetrahydroxy flavone) is one of the most common flavones, which is naturally found in several edible plants and traditional medicine. It is known as a non-toxic compound with anti-inflammatory, antinociceptive, anticarcinogenic, antimutagenic, and antiangiogenic properties. Luteolin has antiproliferative activity against different human hormone dependent cancer cells e.g. breast, prostate, and thyroid. Due to its bacteriostatic properties  and strong antioxidant potential, luteolin is valuable in the management of diverse diseases including peptic ulcers. There are some evidences on wound healing effect of luteolin on diabetic rats and in this work, an in vitro model of wound healing was used to study the wound healing effect of luteolin. Methods: Different concentrations of luteolin were applied in MTT and scratch assay on 3T3 fibroblast cells. FBS-free medium was used as the negative control. Cell proliferation and migration during scratch contraction was calculated. Annexin V and cell cycle analyses were performed to study the effect of luteolin on cell proliferation. Result: The results showed that, scratch contraction was observed significantly (