Abstract:
Natural antioxidants acquired from natural plants seek considerable attention to cure
various ailments including acne, melasma, itching, inflammation, dry skin, atopic
dermatitis and aging because synthetic agents have numerous side effects. The current
study was aimed to fabricate and stabilize the novel carrier system in the form of topical
water-in-oil emulsions (creams); encapsulated with natural extracts of Ananas comosus
(F1), Amomum subulatum(F2) andSyzygium cumini (F3) having comparable antioxidant
activities, their in-vitrocharacterization and in-vivo evaluation on human volunteers.The
extracts of Ananas comosus, Amomum subulatum and Syzygium cuminiwere effectively
prepared and investigated for their biological activities. The antioxidant activities of all
the extracts were analyzed using1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical
method while ascorbic acid was used as a standard antioxidant. The total phenolic
contents were determined in all fruit extracts using Folin-Ciocalteu’s (FC)
method.Antibacterial activities of all extracts were estimated by measuring zones of
inhibition against two species of gram positive bacteria and three species of gram
negative bacteria using agar well diffusion method. Stable water-in-oilemulsions
(creams); F1, F2, F3were formulated using different concentrations of paraffin oil, water
and non-ionic emulsifying agent i.e. polysiloxane polyalkyl polyether copolymer
(Abil ® EM 90) versus respective bases B1, B2, B3 (without fruit extracts).In-vitro
characterization of the formed emulsions F1, F2, F3 and their respective bases B1, B2, B3
were based on to assess the changes on physical stability parameters (color, liquefaction,
centrifugation,viscosity and rheological parameters)when stored at different temperatures
i.e. 8°C, 25°C, 40°C, 40°C ± 75% RH and 50°C and time intervals for a period of 90 days
as per stability study guidelines. In-vivo evaluation was based on to scrutinize the effects
of formulationsF1, F2, F3 and respective bases B1, B2, B3 on various skin parameters
including skin irritancy, melasma, sebum contents, moisture contents, transepidermal
water loss (TEWL) and skin elasticity on human male volunteers for a study period of 12
weeks using photometric device in a draught free room with modulated conditions of
temperature (22-25 0 C) and humidity (55-60%). The study was single blinded, controlled,
split face with 3-groups (F1, F2, F3) containing 11 volunteers each. Statistical tools of
ANOVA test and paired sample t-test were used to evaluate the changes produced.
The results of antioxidant activities of formulations F1, F2, F3 were 92.0%, 89.0% and
81.0% respectively. Selected formulations F1, F2, F3 as well as respective bases B1, B2,xxiii
B3remained stable at all storage conditionswith respect to color, liquefaction,
centrifugation,viscosity and rheology as desired for 12 weeksin vitro study period.All the
samples manifested shear thinning behavior with increasing shear rate indicating
pseudoplastic flow of the formed emulsions. It was evident from the results of in-vivo
studies that no primary skin irritancy was observed with patch test. Besides that,
statistical interpretation indicatedthat treatment with formulations F1, F2, F3 was superior
as compare to respective bases B1, B2, B3 because it significantly (p≤0.05) reduced the
skin irritancy,melasma, sebum and TEWL contents throughout the study period while
significantly (p≤0.05) improves the epidermal hydration level and skin elasticity at the
end of study period compares to baseline value. Conclusively, formulations F1, F2 and F3
encapsulated with natural antioxidants exhibit better physicochemical stability at all
storage conditions and was well tolerated by all volunteers and suitable to treat contact
dermatitis, greasy skin, acne, seborrheic dermatitis and augmenting beauty and attraction
by depigmentation of human skin and represent a propitious improvement in skin barrier
function and used as a functional moisturizing and anti-aging ingredient in topical
skincare products. So, in future there is need to clinically evaluate these formulations in
patients with compromised skin functions i.e. contact dermatitis, melasma, acne vulgaris
and atopic dermatitis in order to explore the actual potential of these fruits.