本研究針對一項可由再生資源所生產的烷基多醣苷類的界面活性劑Triton CG 110之應用作為探討，其特性既安全又環保。透過水蒸餾法對乾燥的香茅（Cymbopogon citratus）葉進行萃取精油，利用Triton CG 110來增加精油的釋放量，此項實驗針對四項因子間的交互作用進行探討。四項因子分別為: Triton CG 110的濃度、液體與原料比、超音波震盪時間以及萃取時間。利用中央合成設計 (CCD)矩陣來優化精油的萃取。以反應曲面法 (RSM)作實驗設計 (DoE)後，透過水蒸餾法得到面心的萃取。結果顯示，利用濃度1339 ppm的Triton CG 110、液體與原料比27、前處理超音波震盪11分鐘以及萃取176分鐘，可得到乾葉重量2.38%的精油產率。
萃取所得香茅精油(LGO)之組成，透過氣相層析-火焰離子化偵檢器(GC-FID)和氣相層析-質譜儀(GC-MS)作分析並使用正癸烷作為內標物。其中，主要成分為檸檬醛，佔萃取重量的81.8%，包含檸檬醛A和檸檬醛B。針對LGO的抗氧化性也進行相關實驗，所得結果顯示，在IC50得2.37 wt%。
以生物可降解的非離子型界面活性劑Triton CG 110分別於溫度25C和4C探討香茅精油於去離子水(DI)中的增溶作用。結果顯示，0.3 wt% LGO和 5 wt% Triton CG 110 的微乳液在兩種溫度下皆具有長達一個月的穩定性
於本研究的下個階段中，對殼聚醣薄膜的性質進行了探討，該殼聚醣薄膜是透過於增塑劑-甘油中加入LGO和殼聚醣所構成。針對薄膜的厚度、不透明度、抗氧化性、機械性質與表面的顯微圖像依序使用掃描電子顯微鏡(SEM) 、衰減式全反射傅立葉轉換紅外光譜儀(ATR-FTIR )及抗菌活性進行分析。
此外，透過瓊脂擴散測定法驗證LGO 和摻入殼聚醣的 LGO對大腸桿菌(Escherichia coli)和金黃色葡萄球菌(Staphylococcus aureus)皆具抗菌能力。薄膜法成功地將 LGO 與殼聚醣混合，其特性適用於食品包裝。

In this study, lemongrass essential oil (LGO) was extracted from Cymbopogon citratus leaves by surfactant-assisted hydrodistillation. Triton CG 110, a plant-derived alkyl polyglucoside (APG) surfactant with alkyl chain of C8- C10 was used. The effect of surfactant concentration, liquid/ material ratio, ultrasonic time, extraction time on the yield of LGO was evaluated with a composite central design (CCD) and response surface methodology (RSM). At the optimal conditions with Triton CG 110 nonionic surfactant at 1339 ppm, a liquid/material ratio of 27, the ultrasonication pre-treatment of 11 min and 176 min as an extraction time, the yield of LGO was 2.38 wt% of dessicated leaves.
The results of gas chromatography (GC) with flame ionization detector (FID) using n-decane as internal standard indicated that the major components in hydrodistilled LGO were citral A and citral B occupying for 81.8%. In the presence of this surfactant, the solubility of LGO into water was improved. The z-average size of solutions made from LGO and Triton CG 110 at the various concentration was measured by dynamic light scattering (DLS). The shelf stability of these solutions was investigated at 25 C over a storage period of one month. The results showed that formula of 0.3 wt% LGO, and 5 wt% Triton CG 110 was stable over a month with the z-average size of 10 nm.
In the next phase of this study, the properties of chitosan films blended LGO was charactized by scanning electron microscopy (SEM), Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR), mechanical property. As comparison, blend films of chitosan and starch at the ratio of 7: 3 was prepared.
Pure lemongrass oil and chitosan films incorporating LGO were studied for their antibacterial and DPPH free radical scavenging properties. The concentration of LGO required to block 50% of DPPH radicals (IC50) was 2.37%, and a chitosan film containing 1% LGO similarly demonstrated 51 % DPPH free radical scavenging. For the antibacterial activity, inhibition zones against both Escherichia coli and Staphylococcus aureus was performed and implying the usefulness of hydrodistilled LGO and chitosan -based films containing LGO in food packaging applications.

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