Leaf Anatomy of the Thirteen Rare Plants in the Northeastern, Thailand

บทคัดย่อ ศึกษากายวิภาคศาสตร์ใบของพืชหายากในภาคตะวันออกเฉียงเหนือ ประเทศไทย จำนวน 13 ชนิด 11 สกุล 9 วงศ์  โดยวิธีการลอกผิวใบ ย้อมด้วยสีซาฟรานิน และตัดตามขวางแผ่นใบและก้านใบด้วยเครื่องตัดเนื้อเยื่อแบบอัตโนมัติ (automatic plant microtome MT-3) ย้อมด้วยสีซาฟรานิน ผลการศึกษา พบลักษณะทางกายวิภาคศาสตร์ของพืชที่ศึกษา มีลักษณะเหมือนและแตกต่างกันของพืชในแต่ละวงศ์ที่มีการศึกษามาก่อน ได้แก่ รูปร่างของเซลล์ในเนื้อเยื่อชั้นผิวใบด้านบนและด้านล่าง ชนิดของปากใบ บริเวณที่พบปากใบ การมีหรือไม่มีขน  รูปร่างตัดตามขวางของเส้นกลางใบและก้านใบ รูปร่างของเซลล์เนื้อเยื่อชั้นผิวใบตัดตามขวาง จำนวนชั้นของเซลล์แพลิเซด การมีหรือไม่มีผลึกและสารสะสม และบริเวณที่พบ  การศึกษากายวิภาคศาสตร์ใบพืชหายากครั้งนี้ส่วนใหญ่เป็นรายงานครั้งแรก จึงสามารถนำมาเป็นข้อมูลเพิ่มเติมทางด้านกายวิภาคศาสตร์ของพืช ABSTRACT Anatomical study of rare plants in the northeastern, Thailand, 13 species 11 genera 9 families were investigated by using epidermal peeling stained with safranin and transverse of leaves by automatic plant microtome MT-3, stained with safranin. The results were found that leaf anatomical features in this study have similar and different characteristics with each the family that was reported in previous research. The analytical characteristics are shape of upper and lower epidermal cells, type of stomata, the distribution of stomata, presence/absence of trichome, shape of midrib and petiole, shape of epidermal cell with a cross-section, the number of palisade layers, the presence/absence of crystals and inclusion and the distribution of stomata. Most of the rare plant of this study were reported for the first time and can be used as additional information to provide a generic description of plant anatomy

Cytotoxic and antiproliferative effects of Streblus asper from northeastern Thailand on A549 lung cancer cells

Thailand's second-leading cause of death is lung cancer. Thai indigenous herbal plants are sought after as an alternative treatment against lung cancer. This work aimed to examine cytotoxic, antiproliferative and antimigratory capacities of different parts of Streblus asper (SA) from northeastern Thailand on A549 lung cancer cells. Plant leaves, twigs, bark and wood were used for ethanolic extraction by maceration. The highest cytotoxicity of 85.46% was found in twig extract (IC50 57.46 µg/mL) assessed by an MTT assay. The lowest IC50 (18.42 µg/mL) was also found in twig extract using a clonogenic assay indicating its most antiproliferative activity in a long-term therapy. In addition, all SA extracts displayed antimigratory activity against A549 cells in a dose-dependent fashion, especially twig extract. Apoptotic characteristics were noticeable in SA extract treated cells. The maximum DPPH-scavenging activity, FRAP value, total phenolic and flavonoid content were found in twig extract. GC-MS analysis revealed that twig extract contained four prominent components namely ethyl-α-D-glucopyranoside, hexadecanoic acid, ethyl ester, lupeol and γ-sitosterol. Real-time PCR results showed that genes (Bcl-2, Bax, p21, and cytochrome c) linked to apoptosis were significantly affected by all SA extracts. The various SA components' ethanolic extracts exhibited moderate-to-high cytotoxic action towards A549 cells. This work will significantly advance the utilization of the plant as an alternative source of medicine for rural Thais, and it paves the way for future research to determine the active compound(s) and anticipate new drug candidates

Population Genetic Structure and Genetic Diversity in Twisted-Jaw Fish, Belodontichthys truncatus Kottelat & Ng, 1999 (Siluriformes: Siluridae), from Mekong Basin

The Mekong River and its tributaries possess the second highest diversity in fish species in the world. However, the fish biodiversity in this river is threatened by several human activities, such as hydropower plant construction. Understanding the genetic diversity and genetic structure of the species is important for natural resource management. Belodontichthys truncatus Kottelat & Ng is endemic to the Mekong River basin and is an important food source for people in this area. In this study, the genetic diversity, genetic structure, and demographic history of the twisted-jaw fish, B. truncatus, were investigated using mitochondrial cytochrome b gene sequences. A total of 124 fish specimens were collected from 10 locations in the Mekong and its tributaries. Relatively high genetic diversity was found in populations of B. truncatus compared to other catfish species in the Mekong River. The genetic structure analysis revealed that a population from the Chi River in Thailand was genetically significantly different from other populations, which is possibly due to the effect of genetic drift. Demographic history analysis indicated that B. truncatus has undergone recent demographic expansion dating back to the end of the Pleistocene glaciation