DOI: 10.14457/tu.the.2015.1560
title: Herbal composites film production for inflamed acne treatment

description: Acne is a chronic skin disease caused by the inflammation of sebaceous glands around hair follicles, where could be seen as red blisters, pustules, and scar on the face. These are the effects of bacteria especially Staphylococcus aureus and Propionibacterium acnes infection. Many investigations have been done on acne and scar treatments using Thai herbs as anti-bacterial agents for S. aureus and P. acnes. This research had developed thermoplastic starch films from cassava starch supplemented with herbal extracts from mangosteen pericarps (MP) and centella (CL), which consisted of three main parts; Part (1) Thermoplastic starch preparation, Part (2) MP and CL extraction, formulations and their anti-microbial, anti-oxidant properties, and also total phenolic contents, and Part (3) Preparation of thermoplastic starch films added with selected formulation of MP-CL extracts and the study of extracts releasing profiles and disk diffusion assay of selected formulation.Part (1), Thermoplastic starches were prepared from cassava starch (ST), glycerol (GLY), and sodium alginate (AL). At first stage, the films were prepared only with cassava starch plasticized with glycerol, and measured the mechanical properties of stickiness (SN), adhesiveness (AN), and cohesiveness (CN). The resulted revealed that the ratio of 30:70 (w/w) of ST, polymer part, and GLY, plasticizer part, exhibited high SN, AN, and CN values of 54.31±3.40 g, 0.86±0.06 g.sec, and 0.34±0.03 mm, respectively, at p-value &lt; 0.05. But the appearance of these films revealed that the wrinkle and unsteady films instead.Thus, to improve the quality of the films both appearance and high mechanical properties, sodium alginate (AL) was then added into the polymer part, 30% w/w of the ratio, while GLY, plasticizer part was kept constant at 70% w/w. The ratios between ST and AL in polymer part were varied at 10% (w/w) interval from 100:0 to 0:100 of ST:AL ratio. Ten newly prepared composite films were done on SN, AN, and CN measurement. The results showed that the films with polymer ratio (ST:AL) of 90:10 gave the high SN, AN, and CN values of 68.31±0.62 g, 1.65±0.05 g.sec, and 0.55±0.01 mm, respectively, at p-value &lt; 0.05, with steady and non-wrinkle films. These films were selected to be supplemented with herbal extracts before conducting the third part of this study, extracts releasing profiles of the invented films.Part (2), in this part, MP and CL were extracted by maceration and Soxhlet methods, respectively, and prepared for 7 MP-CL formulations by varying and combining MP and CL extracts at 7 different ratios (w/w), MG0, MG2, MG4, MG5, MG6, MG8, and MG10. These formulations were then measured the anti-oxidant activities, total phenolic contents (TPC), and anti-microbial activities. The anti-oxidant activity was done by using DPPH scavenging assay comparing to the standard ascorbic acid. It was found that MG8 gave the highest anti-oxidant activity with 17.10 µg/mL of IC50 and 69.99±4.67% of radical scavenging among five formulations, MG2 to MG8. However, its activity was lower than that of MP extract alone (MG10), 14.80 µg/mL of IC50 and 75.93±12.16% of radical scavenging, while CL extract alone (MG0) exhibited the lowest anti-oxidant activity of 61.70 µg/mL of IC50 and 31.79±10.54% of radical scavenging. The TPC results also confirmed the effectiveness of MP over the CL, as the TPC for MP and CL was found to be 5,179.64±542.66 and 2,418.81±123.10 mg GAE (Gallic Acid Equivalent)/g extract, respectively. This study also investigated on the anti-microbial activities of all MP-CL formulations by Minimal Inhibitory Concentration (MIC) using broth micro-dilution method. These tests were done to compare the formulations with gentamycin solution against S. aureus DMST 8840 and P. acnes DMST 14916. It was found that MG8 and MG10 had the highest anti-microbial activity with MIC values of 1.95 and 15.63 µg/mL against S. aureus and P. acnes, respectively. The MP-CL formulation MG8 was then selected to add into the anti-acne composite films mentioned in Part (1).Part (3), the composite films supplemented with MG8 were then carried out with 480 minutes herbal extracts releasing profiles. It was found that the selected films gave the cumulative releasing content of 4.74±0.26% (w/w) at 30 minutes and remained approximately constant after that. The disk diffusion assay showed that the inhibition effect against S. aureus DMST 8840 and P. acnes DMST 14916 exhibited the large inhibition zone of 17.56±0.20 and 14.89±0.11 mm, respectively.