Rapid Discrimination of Indonesian Herbal Medicines by Using Electronic Nose Based on Array of Commercial Gas Sensors

Abstract

The aim of this study is to discriminate herbal medicines (here after referred to as herbals) by an electronic nose (e-nose) based on an array of eight commercially gas sensors and multivariate statistical analyses. Seven kinds of herbal essential oils purchased from local market in Yogyakarta Indonesia, including zingiberofficinale (ZO), kaempferiagalanga (KG), curcuma longa (CL), curcuma zedoaria (CZ), languasgalanga (LG), pogostemoncablin (PO), and curcuma xanthorrizharoxb (CX) were measured by using this e-nose consecutively. Due to the use of dynamic headspace in this e-nose, data for one cycle (sampling and purging) were recorded every five second for 10 cycles. Each kind of herbals was analyzed for five replications and relative amplitude of the responses was extracted as a feature. The statistical analyses of principal component analysis (PCA) and cluster analysis (CA) were used for discriminating samples. The PCA score plot shows that these 35 essential oil samples were separated into 7 groups based on similarity of patterns. The first two components, PC1 and PC2, capture 96.2% of data variance. Meanwhile, by using 80% similarity, the CA clusters 7 herbals into 3 classes. In this case, the first class consists of ZO and CZ and the second class consists of KG, CL, LG and CX, while the PO sample is clustered in the third class. These classes need to be validated using a standard analytical instrument such as GC/MS. The technique shows some advantages including easy in operation because of without any sample preparation, rapid detection, and good repeatability.

Analisis Cluster Bahan Herbal Berdasarkan Fitur Respon E-Nose

“…Metode yang digunakan pada penelitian ini adalah metode penelitian sekunder atau dikenal juga dengan metode penelitian analisis data sekunder. Data yang digunakan pada penelitian ini diperoleh dari penelitian [9] berupa respon e-nose terhadap lima macam bahan herbal. Adapun sampel yang digunakan berjumlah 100 sampel dari lima buah bahan obat herbal, yang terdiri dari jahe (ZO), kencur (KG), kunyit (CL), lengkuas (LG), dan temulawak (CX).…”

Comparative analysis of feature extraction methods in the clustering of electronic nose response correlated with GC/MS analysis

“…Each kind of herbal medicine consists of five samples. The sample was measured by e-nose employed an array of metal oxide semiconductor (MOS) gas sensor, including TGS-813, TGS-822, TGS-2600, TGS-826, TGS-2611, TGS-2620, TGS-2612 and TGS-2602.This e-nose has been used in the previous experiments for discriminating vegetable oils and animal fats [11], and herbal essential oils [12]. GC/MS analysis was performed by the Shimadzu 2010A to validate the e-nose measurement.…”