微生物的存在會造成化粧品品質劣變，構成消費者使用的風險，因此化粧品中需添加防腐劑。但消費者使用化粧品後產生過敏反應，推測許多的可能是因為防腐劑的添加所造成的。因此，本研究尋求天然的精油來代替。
本研究探討迷迭香(Rosmarinus officinalis L.)與檸檬香茅(Cymbopogon citratus)精油依不同比例添加於成品中，測其於配方中之防腐效能，並使用GC/MS分析此二種精油的成份。結果顯示，迷迭香精油主成分是以1,8-cineole (24.70%)為主，檸檬香茅精油則是geranial (17.68%)、cis-citral (15.06%)含量較多。在防腐效能試驗部分，兩種精油以單獨添加，或是依同等比例混合，對化粧品不得驗出之大腸桿菌、金黃色葡萄球菌及綠膿桿菌皆具有不錯的防腐效果，對黑黴菌的防腐效果以檸檬香茅精油較佳，單獨使用低濃度添加於成品中即具有很好的防腐效果，迷迭香精油需與之混合使用亦具有不錯的防腐效果。
綜合論文研究結果，精油可以單獨添加或是合併使用於成品中以達防腐效果，具開發潛力。 Microorganism contamination is one of the most important problems in cosmetic industry, and microorganism lead to product degradation or, in the case of pathogens, constitute a risk for the health of the consumer. Therefore, preservatives inhibiting the growth of microorganisms are added to a product, but allergies after using cosmetics occur more and more frequently, which is quite often associated with the presence of synthetic preservatives. For this reason, this study was to verify the antimicrobial activity of essential oils as the components of preservative.
The aim of the study was to test preservative effectiveness of Rosmarinus officinalis L. and Cymbopogon citratus essential oils alone or combination in the formulation during the challenge test. The compositions of the two essential oils, were analyzed by GC/MS. The main components of Rosmarinus officinalis L. essential oil is 1,8-cineole (24.70%). Cymbopogon citratus essential oils contains geranial (17.68%) and cis-citral (15.06%).
In the challenge test, all formulation had preservative abilities against
Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. However, all formulations had preservative abilities against Aspergillus niger administered alone or in combination of Cymbopogon citratus essential oil.
In summary, the essential oils can be added individually or in com- bination into cosmetics to achieve the preservative effect.
