EFFECT OF COCONUT OIL ON HAIR DAMAGE 181 PROTEIN LOSS IN ug/g OF HAIR 440- 253 i 400 36O 32O 280 240 200 160 120 80 40- 0 COCONUT OIL SUNFLOWER COCONUT SUNFLOWER OIL OIL OIL PRE-WASH TYPES OF OILS POST-WASH [] WITHOUT [] WITH Figure 4. Comparison of protein loss from hair exposed to UV treatment. both sides. After every five strokes, the comb was dipped in 50 ml of water contained in a beaker to dislodge the debris. The same 50 ml of water was used to collect all the loosely held protein eluted from the comb for a given tress. The entire tress was dipped in water after every five strokes to collect the damaged and dislodged cuticle cells. The water suspension was tested for protein content using the Lowry method. It was com- pared against standard bovine serum albumin procured from Sigma Chemical Co. This bovine serum albumin was diluted so as to get readings within which the maximum and minimum reading for the sample would fall. The method involves the formation of a copper-protein complex in alkaline solution that, in turn, reacts with phosphomolybdic- phosphotungstate reagent (Folin-Ciocaltaeu Phenol reagent) to yield an intense blue- colored solution, which is analyzed spectrophotometrically. It was checked that the blue color development occurring in both standard and sample was of the same color with different intensity, depending on the amount of protein being eluted from the hair fibers, thereby indicating that none of the oils was interfering in the color development. The methodology is discussed to a great extent in reference (2). Water fete,rio, i,dex (WRI). The SLES-washed tresses were soaked in a 0.01% solution of polysorbate 80 for 30 min. Following this procedure, the entire tress was placed over a hollow glass cylinder with a glass lid with perforations to hold the tress properly and to separate the hair from capillary water in the glass centrifuge tube of diameter 3 cm and height 8 cm. It was centrifuged at 8000 rpm for 15 min to remove capillary water

182 JOURNAL OF COSMETIC SCIENCE PROTEIN LOSS IN ug/g OF HAIR 200 COCONUT OIL MINERAL OIL SUNFLOWER OIL TYPES OF OILS [] NORMAL WITHOUT [] BLEACHED WITHOUT [] NORMAL WITH [] BLEACHED WITH Figure 5. Comparison of protein loss from normal and bleached hair in a salon trial. and then weighed. In the next step, the dry weight of the hair was determined by drying the tress in a vacuum oven at 50øC for 90 min, and then weighing it again. The percentage water retention index (WRI) is given by: WRI -- (Wwe t - Wary ) 100/Wary Half-head tests, Each half-head test involved 20 clients each with normal and bleached hair. The hair was parted in the middle and half the head was treated with the respective oil (3 ml approx.) and massaged thoroughly, while the other half was left without treatment. The oil was left on the hair for approximately 8 hr. Then the hair was washed with warm water (28øC, 200 ppm hardness) using 20% SLES, and rinsed well to remove any residue. To avoid inherent differences in damage from left to right side, the appli- cation of the treatment was randomized. Panelists with odd numbers were treated on the left side, while those with even numbers were treated on the right side. After shampooing and rinsing, the hair was combed with a fine-tooth comb (separate