We examined the potential of virgin coconut oil (VCO) incorporated in gellan gum (GG) films as a dressing material. Pure GG film is extremely brittle and inclusion of 0.3% (w/w) VCO in the GG film (GG-VCO3) improved the toughness (？J？g？1) of the composite films. Swelling properties and water vapor transmission rates of GG-VCO composite films decreased, whereas thermal behavior values increased upon the addition of higher concentrations of VCO. Cell studies exhibit that the VCO is noncytotoxic to human skin fibroblast cells (CRL2522) with limited cell growth observed on GG-VCO3 films at 1,650 cells/well after incubation for 72？h which could be due to hydrophobic influence of the material surface. The qualitative and in vitro quantitative antibacterial results revealed that VCO does not possess strong bacterial resistance against all four tested bacteria, that is, two Gram-positive (Staphylococcus aureus and Staphylococcus epidermidis) and two Gram-negative bacteria (Pseudomonas aeruginosa and Proteus mirabilis). 1. Introduction The development of wound care materials continues to cater to the various different needs of damaged skin problems. Biopolymers such as gellan gum (GG) have received great attention, particularly in the field of biomedicine, due to their biocompatibility and biodegradability properties. Gellan gum is produced by Pseudomonas elodea and consists of a repeating unit of tetrasaccharide: 1,3-linked -D-glucose, 1,4-linked -D-glucuronic acid, 1,4-linked -D-glucose, and 1,4-linked -L-rhamnose. Gellan gum has been approved by the United States Food and Drug Administration (US FDA) and the European Union (EU) labels it as E 415 in EU regulation for the use in food industry. It is currently popular in the development of tissue engineering. Studies on medical and pharmaceutical applications of gellan gum have also been reported which include “dual layer films” [1], bioink substrates for printing living cells [2], use for dressing material [3], and use as a vehicle for ophthalmic drugs [4]. Besides that, gellan gum demonstrates good compatibility with live cells such as mouse fibroblast (L929 cell line), human dermal fibroblasts (HDFs), human fetal osteoblasts (hFOBs 1.19), human nasal cartilage, and rat bone marrow cells (rBMC) [1, 5–7]. On the other hand, virgin coconut oil (VCO) is one of the recent promising candidates in promoting healing process due to its biocompatibility property and antibacterial activities. Previous studies reported that pure VCO examined through in vivo test could enhance the healing process. Nevin and Rajamohan
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