Vichien Keeratinijakal

Identification and characterization of Curcuma comosa Roxb., phytoestrogens-producing plant, using AFLP markers and morphological characteristics

‘Waan chak modlook’ ( Curcuma comosa Roxb.) is an important medicinal plant of Thailand, but the high similarity in morphological characteristics observed among Curcuma spp. may cause confusion in its utilization. The amplified fragment length polymorphism (AFLP) marker was used to identify and elucidate the phylogenetic relationships among 97 accessions of ‘Waan chak modlook’ collected throughout Thailand. Nine AFLP primer combinations generated a total of 202 bands, of which, 158 bands were polymorphic, with an average of 17.56 bands per primer pair. Pairwise similarity estimated between all samples ranged from 0.39 to 1.00 with an average of 0.67. The phylogenetic tree derived from AFLP data showed that the ‘Waan chak modlook’ accessions were divided into five clusters. Based on morphological characterizations, all samples could be assigned to four species: Curcuma sp.; Curcuma latifolia Rosc.; Curcuma elata Roxb.; and C. comosa . The results indicated that there were other Curcuma species that were misused as C. comosa . The DNA fingerprint data along with the morphological data provided the keys for the accurate identification of C. comosa from the other three related species.

Near infrared quantitative analysis of total curcuminoids in rhizomes of Curcuma longa by moving window partial least squares regression

The present paper reports an application of moving window partial least squares regression (MWPLSR) to determine total curcuminoid content in rhizomes of Curcuma longa by near infrared (NIR) spectroscopy. The MWPLSR method was applied to original and pretreated NIR data of Curcuma longa rhizomes to select informative regions for total curcuminoids. Afterward, partial least squares (PLS) calibration models were developed and compared for each spectral region proposed by MWPLSR and the whole spectral region. The best PLS calibration model for total curcuminoids was obtained from 2nd derivative NIR spectra in the region of 2040–2486 nm. The standard error of prediction was 1.00%w/w and the ratio of prediction to deviation was 4.9 when using seven principle components. NIR spectroscopy combined with MWPLSR can lead to better calibration models with higher performance.

Microscopic characterization as a tool for separation of Stemona groups.

Introduction: Stemona plants have been traditionally used as an insecticide, scabicide and pediculocide, and for the treatment of skin and respiratory diseases. Stemona can be separated into two groups according to their morphological characters and bioactive components i.e. stichoneurine and protostemonine groups. Protostemonine group contains alkaloids that possess potent insecticidal activity while stichoneurine group accumulates alkaloids with antitussive activity. In Thailand, a vernacular name “Non Tai Yak” refers to the roots of different species of Stemona, making it confusing to discern different species. The purposes of this study are to investigate the microscopic characteristics of the roots of seven species of Stemona growing in Thailand and to distinguish and identify these groups of Stemona. Methods: Cross-sectional histology of fresh root samples and powdered drug characteristics of 7 species of Stemona were studied under a microscope. Results: The roots of Stemona in the stichoneurine group (S. tuberosa and S. phyllantha) contained a non-lignified large pith while the roots of protostemonine group (S. burkillii, S. cochinchinensis, S. collinsiae, S. curtisii and S. kerrii) had a small lignified one. The powder of stichoneurine group contained numerous thin-walled parenchyma, but only few thick-walled parenchyma and lignified fibers and vessels were present. In contrast, thick-walled parenchyma and lignified fibers and vessels were frequently found in the powdered roots of protostemonine Stemona. These characteristics could be used to discern between Stemona in the stichoneurine and protostemonine groups. Conclusions: The microscopic characterizations can be used as a primary tool to categorize and separate 2 main Stemona groups.

Simultaneous quantification of stemocurtisine, stemocurtisinol and stemofoline in Stemona curtisii (Stemonaceae) by TLC-densitometric method.

Stemona curtisii Hook. F. (Family Stemonaceae), a prominent species distributed in the south and southwest of Thailand, has widely been used as a natural pesticide and as treatment for head lice and skin diseases. This study developed a thin-layer chromatography (TLC)-densitometric method for the simultaneous quantification of major components--stemocurtisine, stemocurtisinol and stemofoline--in the extracts from the roots of S. curtisii collected from 10 locations in Thailand. Components were found in the ranges of 0.0353-0.1949, <0.0121-0.0859 and 0.0733-0.1689 percent dry weight, respectively. The method was validated for linearity, precision, accuracy, robustness, limit of detection and limit of quantitation. The linearity was found over the range of 40-320 ng/spot with a good correlation coefficient (r > 0.9866). Intra-day and inter-day precision showed a relative standard deviation of less than 6%. The accuracy of the method was determined by a recovery study, and the average recoveries were 100.4, 100.2 and 100.3% for stemocurtisine, stemocurtisinol and stemofoline, respectively. The proposed TLC-densitometric method was found to be simple, precise, specific and inexpensive, and can be used simultaneously for the routine quality control of raw materials of S. curtisii roots, extracts and their products, and also other products containing these markers.

An in vitro study of the bioefficacy of essential oil blends against Aedes aegypti (Linn.) and Anopheles dirus (Peyton and Harrison) by using membrane feeding apparatus

Nutthanun Auysawasdi, Sawitri Chuntranuluck, Vichien Keeratinijakal, Siriporn Phasomkusolsil, Silas A Davidson Department of Biotechnology, Faculty of Agro-Industry, Kasetsart University, 50 Ngam Wong Wan Road, Ladyaow, Chatuchak, Bangkok 10900, Thailand Department of Agronomy, Faculty of Agriculture, Kasetsart University, 50 Ngam Wong Wan Road, Ladyaow, Chatuchak, Bangkok 10900, Thailand Department of Entomology, Armed Forces Research Institute of Medical Science, Bangkok 10400, Thailand Journal of Coastal Life Medicine 2017; 5(2): 82-87