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Grammatophyllum speciosum is the largest orchid species and a well-known traditional medicinal plant. Due to skin aging, natural products that inhibit this process can attract the attention of consumers and scientists because radical-scavenging activity, collagenase inhibition, and inflammatory suppression are valuable in dermatological applications. This study investigated the phytochemicals in G. speciosum leaves extracts that have cosmeceutical potentials, including radical-scavenging, anticollagenase, and anti-inflammatory abilities. G. speciosum leaves were extracted using water-based extraction methods. High-resolution mass spectrometry was used to identify the phytochemicals in the extracts. Fibroblast and keratinocyte cell cytotoxicity was determined. Antioxidant abilities were measured using DPPH and ABTS assays. The effect of the extracts on nitric oxide (NO) in macrophage cells was investigated. ELISA of the collagenase enzyme was determined. A total of 721 annotated metabolites were identified in the extracts. Vitexin and orientin were the most abundant metabolites. Cell viability was >80% in both cell lines when the extract concentration was <1 mg/mL. The IC50 values for DPPH and ABTS were 56 and 117 μg/mL, respectively. Furthermore, the extracts revealed that NO and collagenase activity were suppressed by 42% and 23%, respectively. The extracts can suppress ROS, inflammatory, and collagenase activities without causing fibroblast and keratinocyte cell death. Thus, this study provides information on metabolites in G. speciosum leaves, which is promising as cosmeceuticals or pharmaceuticals with anti-inflammatory and anti-collagenase activities.

Leaf idioblasts can have a significant effect on leaf-lamina water relations. Idioblasts likely function as a water buffering system for thin leaves in tropical species. The association of idioblast prominence with leaf water buffering is greatest for epiphytic species with thin leaves. Thus, the proliferation of leaf idioblasts may have been an important innovation for species diversification into tropical epiphytic habitats.

Background Thailand is a country with large diversity in rice varieties due to its rich and diverse ecology. In this paper, 300 rice accessions from all across Thailand were sequenced to identify SNP variants allowing for the population structure to be explored. Results The result of inferred population structure from admixture and clustering analysis illustrated strong evidence of substructure in each geographical region. The results of phylogenetic tree, PCA analysis, and machine learning on population identifying SNPs also supported the inferred population structure. Conclusion The population structure inferred in this study contains five subpopulations that tend to group individuals based on location. So, each subpopulation has unique genetic patterns, agronomic traits, as well as different environmental conditions. This study can serve as a reference point of the nation-wide population structure for supporting breeders and researchers who are interested in Thai rice.

Background Tecoma stans (L.) Juss. ex Kunth is a well-known medicinal plant found in tropical and subtropical regions. It contains a broad range of bioactive compounds that exhibit many biological effects, including antidiabetic, antibacterial, and antioxidative activities. However, the effect of natural peptides from T. stans against cancer progression and free radical production is unknown. This study aims to evaluate the cytotoxic, anti-metastatic, and antioxidative activities of natural peptides from T. stans on A549 cells. Methods The natural peptides were extracted from the flower of T. stans using the pressurized hot water extraction (PHWE) method, followed by size exclusion chromatography and solid-phase extraction-C18. The cytotoxic and anti-metastatic effects of natural peptides were evaluated using MTT and transwell chamber assays, respectively. The free radical scavenging activity of natural peptides was determined using ABTS, DPPH, and FRAP assays. The cells were pretreated with the IC50 dosage of natural peptides and stimulated with LPS before analyzing intracellular reactive oxygen species (ROS) and proteomics. Results Natural peptides induced cell toxicity at a concentration of less than 1 ng/ml and markedly reduced cell motility of A549 cells. The cells had a migration rate of less than 10% and lost their invasion ability in the treatment condition. In addition, natural peptides showed free radical scavenging activity similar to standard antioxidants and significantly decreased intracellular ROS in the LPS-induced cells. Proteomic analysis revealed 1,604 differentially expressed proteins. The self-organizing tree algorithm (SOTA) clustered the protein abundances into eleven groups. The volcano plot revealed that the cancer-promoting proteins (NCBP2, AMD, MER34, ENC1, and COA4) were down-regulated, while the secretory glycoprotein (A1BG) and ROS-reducing protein (ASB6) were up-regulated in the treatment group. Conclusion The anti-proliferative and anti-metastatic activities of natural peptides may be attributed to the suppression of several cancer-promoting proteins. In contrast, their antioxidative activity may result from the up-regulation of ROS-reducing protein. This finding suggests that natural peptides from T. stans are viable for being the new potential anti-cancer and antioxidative agents.