BACKGROUND

Comedogenicity is the potential to promote follicular blockage leading to the formation of microcomedones and cosmetic acne. Mills and Kligman compared the established rabbit ear assay (REA) ratings with studies in human participants using the skin surface biopsy. They concluded that some materials considered comedogenic on REA were non-comedogenic in human skin.

Using a modification of the Mills and Kligman skin surface biopsy, this study aimed to determine the comedogenic potential of ten commonly used cosmetic oils: almond oil, argan oil, avocado oil, castor oil, coconut oil, grape seed oil, mineral oil, olive oil, safflower oil, and sunflower oil.

Each participant received a test patch with twelve chambers on the skin of the back, with each chamber containing filter paper saturated with each of the respective oils, the positive control (octyl palmitate), and the negative control (unsaturated filter paper). These patches were changed 3 times weekly for 4 weeks. Cyanoacrylate skin surface biopsies were done to determine the number of follicles and microcomedones at baseline and after 4 weeks of exposure.

Thirty individuals were enrolled in the study. All participants underwent baseline and final skin surface biopsies. Almond oil showed a significant increase with a 112.9% increase in the number of comedones from baseline.

The results of this study show that certain oils commonly used as ingredients in cosmetic products, such as almond oil, are comedogenic.

Desmos chinensis is a climber tree. Branches brown pubescent, leaves glaucous underneath, petals yellow. This tree distributes in many provinces of Viet Nam, mostly in Yen Bai, Ha Giang, Thai Nguyen, Bac Giang, Vinh Phuc, Quang Ninh, Hoa Binh, Ninh Binh, Quang Binh, Ha Tinh, Thua Thien Hue, Kontum, Dong Nai. The oil yield was 0.2% from air-dried flowers. The essential oil of Desmos chinensis was analysed using GS and RMN. 13 constituents have been identified, including beta-caryophyllene (28.9%), bicyclogermacren (11.5%), alpha-humullene (7.2%), D-germacren (7.2%), beta-elemene (6.4%)
chemistry ; Flowers ; Oils ; Oils, Volatile

Limnophyla rugosa is an erect-semi aquatic, fragrant, annual herb, up to 50 cm tall. Stem simple or branch, glabrous to hirsute, rooting from the lower nodes, leaves decussate, ovate-lanceolate to oval elliptical 2-8cmx1-5 cm, flowers solitary in axillary; sometimes in axillary pendunculate clusters with up to 7 sessile. Limnophyla rogusa occurs in moist along treams,pools and rice field from sea-level up to 1500 m attitude. Yield of essential oil from aerial parts of Limnophyla rogusa was 0.18 percent by air-dry material, 23 constituents of the essential oil were identified by GC/MS. Major constituent of essential oil was anethol (89.4%)
Oils, Volatile ; oils ; Chemistry ; Plants ; Medicine, Traditional

Chemical components of essential oil of rhizoma (Alpinia pinnanensis T. L. Wu & Senjen) were analysed by capillary GC and GC/MS methods. Antimicrobiological activities were tested. Results showed principal components of essential oil are sesquitecpenoid and their derivatives (nearly 70%). The antibacteria spectrums of essential oil were broad, especially it has strong activities for negative gram bacteria, E. coli and S. aureus
Oils, Volatile ; Chemistry ; Oils ; Medicine, Traditional

Chemical components of essential oil of Piper nigrum L. and essential oil of Piper betle L. were identified by GC/MS method. The main constituents in essential oil of Piper nigrum L. are D-limonene, alpha-pinene, beta-pinene and D3-carene. The main components of essential oil of Piper betle L. are eugenyl acetate or isoeugenyl acetate, alylpyrocatechol diacetate, eugenol or isoeugenol, caryophylen
Oils, Volatile ; Chemistry ; Oils ; Medicine, Traditional

This paper presented a study on the dynamic of essential oil accumulation in Japanese mint SK33 (M. arrvensis L.) and the influence of storage time on its quantity and quality. This mint was cultivated at Co Nhue experimental station, Tu Liem district, Ha Noi City between 2000 and 2002. The results showed that during the vegetation and development process, the essential oil content in the plant gradually increased and achieved maximum at first branch flowering stage and reduced to minimum at the end of flowering stage. The menthol content in essential oil of Japanese mint SK33 reached the highest value at full flowering stage (81.79%). The best harvest time for this mint is from the beginning flowering stage to full flowering period. After harvesting the whole plants can be stored during 20 days without the change in content and quality of essential oil
oils ; Conservation of Natural Resources ; Oils, Volatile

Materials and methods: Wild growing Adenosma caeruleum R.Br. (Scrophulariaceae) was collected at Dak Mil district (Dak Lak province) in July 2002 for oil preparation. The oil analysis was carried out by a combination of capillary gas chromatography and mass spectrometry. Results: The essential oil was obtained from the aerial part of the plant at the yield of 0.5% compared with dried materials. 38 chemical compounds were identified. The major components were thymol (24.67%), alpha-humulene (16.44%), thymyl methylether (12.59%), gamma-terpinene (12.26%), beta-caryophyllene (5.82%), beta-bisabolene (5.67%), p-cymene (4.58%), humulene oxide (3.59%) and caryophyllene oxide (2.76%).
Scrophulariaceae ; Oils ; Oils, Volatile ; Plants ; Medicine, Traditional

Study on chemical compositions of essential oil of Cyperus rotundus L. extracted from the stem and root of plant Cyperus rotundus L. from Nghe An in October 2003. Results: 49 components were detected by combination of GC and GC/MS, in which 18 had been identified. Monoterpens accounted for high level in essential oil. The main components were -cyperon (14.5%), cyperen (7.8%), caryophylen oxid (6.5%), -selinen (6.3%). Essential oil level was 0.2% for fresh samples. Essential oil had soil-yellow color and specific slight perfume
Oils, Volatile ; Chemistry ; Cyperus

Research by …..method combined with block spectrum. High content of Artemisia ketone is in essential oil of Bungaria, almost no have in essential oil of Viet Nam. In bloom period, essential oil content of Artemisia annual L in Viet Nam only attained 0,1-0,2%, meanwhile Bungari’s attained 0,5-0,8% (reckon follow fresh weight). That showed Artermisia annual essential oil of Viet Nam no has significant meaning in economic and reality.
Artemisia ; Chemistry ; Oils, Volatile

In Vietnam and Bulgaria, accumulation of essential oils of Artemisia annua L. depending on the period of it's growth, was investigated. The content change of compound is significant with 3 phases: Phase 1 - From tree began growth to first 6 months, phase 2 - from second month to fourth month, phase 3 - from fifth month to sixth month (the tree is in flower). Concentration of artemisia annua L. is highest at phase 3 when the tree is in flower
Oils, Volatile ; Artemisia ; plants