Oral Bioavailability, Tissue Distribution, Metabolism, and Excretion of Panduratin A from Boesenbergia rotunda Extract in Healthy Rats.

Background: Our previous studies in vitro and in vivo have shown anti-severe acute respiratory syndrome coronavirus 2 activity of fingerroot extract (Boesenbergia rotunda) and its phytochemical panduratin A. Aim of Study: Therefore, the objective of this study was to determine the pharmacokinetic profiles of panduratin A, as a pure compound and in fingerroot extract, in rats. Materials and Methods: Male rats were randomly divided into four groups. Rats underwent intravenous administration of 4.5 mg/kg panduratin A, a single oral administration of 45 mg/kg panduratin A, or a multiple oral administration of 45 mg/kg panduratin A-consisted fingerroot extract for 7 consecutive days. The concentrations of panduratin A in plasma, tissues, and excreta were measured by using LCMS with a validated method. Results: The rats showed no change in health status after receiving all test preparations. The absolute oral bioavailability of panduratin A administered as pure panduratin A and fingerroot extract were approximately 9% and 6%, respectively. The peak concentrations for the single oral doses of 45 mg/kg panduratin A and fingerroot extract, were 4833 ± 659 and 3269 ± 819 µg/L, respectively. Panduratin A was mostly distributed in gastrointestinal organs, with the highest tissue-to-plasma ratio in the stomach. Approximately 20-30% of unchanged panduratin A from the administered dose was detected in feces while a negligible amount was found in urine. The major metabolites of administered panduratin A were identified in feces as oxidation and dioxidation products. Conclusion: Panduratin A from fingerroot extract showed low oral bioavailability, good tissue distribution, and partially biotransformed before excretion via feces. These findings will assist in developing fingerroot extract as a phytopharmaceutical product for COVID-19 treatment.

Kaempferia parviflora extract and its component polymethoxyflavones suppress adipogenic differentiation of human bone marrow-derived mesenchymal stem cells via the AMPK pathway.

BACKGROUND: Kaempferia parviflora Wall. ex. Baker (KP) has been reported to exhibit anti-obesity effects. However, the detailed mechanism of the anti-obesity effect of KP extract (KPE) is yet to be clarified. Here, we investigated the effect of KPE and its component polymethoxyflavones (PMFs) on the adipogenic differentiation of human mesenchymal stem cells (MSCs). METHODS AND RESULTS: KPE and PMFs fraction (2.5 µg/mL) significantly inhibited lipid and triacylglyceride accumulation in MSCs; lipid accumulation in MSCs was suppressed during the early stages of differentiation (days 0-3) but not during the mid (days 3-7) or late (days 7-14) stages. Treatment with KPE and PMFs fractions significantly suppressed peroxisome proliferator-activated receptor-γ (PPARγ), CCAAT/enhancer binding protein α (C/EBPα), and various adipogenic metabolic factors. Treatment with KPE and PMFs fraction induced the activation of AMP-activated protein kinase (AMPK) signaling, and pretreatment with an AMPK signaling inhibitor significantly attenuated KPE- and PMFs fraction-induced suppression of lipid formation. CONCLUSIONS: Our findings demonstrate that KPE and PMFs fraction inhibit lipid formation by inhibiting the differentiation of undifferentiated MSCs into adipocyte lineages via AMPK signaling, and this may be the mechanism underlying the anti-obesity effects of KPE and PMFs. Our study lays the foundation for the elucidation of the anti-obesity mechanism of KPE and PMFs.

A novel peptide derived from Zingiber cassumunar rhizomes exhibits anticancer activity against the colon adenocarcinoma cells (Caco-2) via the induction of intrinsic apoptosis signaling.

This paper presents the initial exploration of the free radical scavenging capabilities of peptides derived from protein hydrolysates (PPH) obtained from Zingiber cassumunar rhizomes (Phlai). To replicate the conditions of gastrointestinal digestion, a combination of pepsin and pancreatin proteolysis was employed to generate these hydrolysates. Subsequently, the hydrolysate underwent fractionation using molecular weight cut-off membranes at 10, 5, 3, and 0.65 kDa. The fraction with a molecular weight less than 0.65 kDa exhibited the highest levels ABTS, DPPH, FRAP, and NO radical scavenging activity. Following this, RP-HPLC was used to further separate the fraction with a molecular weight less than 0.65 kDa into three sub-fractions. Among these, the F5 sub-fraction displayed the most prominent radical-scavenging properties. De novo peptide sequencing via quadrupole-time-of-flight-electron spin induction-mass spectrometry identified a pair of novel peptides: Asp-Gly-Ile-Phe-Val-Leu-Asn-Tyr (DGIFVLNY or DY-8) and Ile-Pro-Thr-Asp-Glu-Lys (IPTDEK or IK-6). Database analysis confirmed various properties, including biological activity, toxicity, hydrophilicity, solubility, and potential allergy concerns. Furthermore, when tested on the human adenocarcinoma colon (Caco-2) cell line, two synthetic peptides demonstrated cellular antioxidant activity in a concentration-dependent manner. These peptides were also assessed using the FITC Annexin V apoptosis detection kit with PI, confirming the induction of apoptosis. Notably, the DY-8 peptide induced apoptosis, upregulated mRNA levels of caspase-3, -8, and -9, and downregulated Bcl-2, as confirmed by real-time quantitative polymerase chain reaction (RT-qPCR). Western blot analysis indicated increased pro-apoptotic Bax expression and decreased anti-apoptotic Bcl-2 expression in Caco-2 cells exposed to the DY-8 peptide. Molecular docking analysis revealed that the DY-8 peptide exhibited binding affinity with Bcl-2, Bcl-xL, and Mcl-1, suggesting potential utility in combating colon cancer as functional food ingredients.

Albiflorenes A-L, polyoxygenated cyclohex(a/e)ne diterpene esters from Kaempferia albiflora.

Twelve polyoxygenated cyclohex(a/e)ne diterpene esters, named albiflorenes A-L (1-12), were isolated from the whole plants of Kaempferia albiflora, known as "Prao Mang Mum." Their structures and relative stereochemistry were determined by extensive spectroscopic analysis. Furthermore, the comparison of experimental electronic circular dichroism (ECD) curves with the curves predicted by TDDFT was used to determine the absolute configurations. Albiflorenes contain polyoxygenated cyclohexane (or cyclohexene) derivatives, which are linked to either isopimarane or abietane diterpene acid units. The discovery marks the first occurrence of a conjugate between polyoxygenated cyclohexane (or cyclohexene) rings and diterpenoids. Among the isolates, albiflorene C specifically exhibited antibacterial activity against Bacillus cereus with MIC and MBC values of 3.13 and 6.25 µg/mL, respectively.

Six new phenylpropanoids from Kaempferia galanga L. and their anti-inflammatory activity.

Kaempferia galanga L. is an aromatic medicinal plant belonging to the Zingiberaceae family. Its rhizome has been widely used as traditional Chinese medicine and a flavor spice for a long time. In this study, six previously undescribed phenylpropanoids, including four [2+2]-cycloaddition-derived cyclobutane natural products (1-4), and two phenylpropanoids (5-6) were isolated from the rhizomes of K. galanga L. Their structures were elucidated by spectroscopic methods, single-crystal X-ray diffraction, NMR calculation, and ECD spectra calculation. These cyclobutane derivatives were isolated from K. galanga for the first time. Furthermore, compounds 1-6 were evaluated for the potential inhibitory activities on NO production and NF-κB nuclear translocation in LPS-triggered RAW 264.7 macrophages. The results showed that the isolated compounds have a moderate anti-inflammatory activity measured on their potency to inhibit NO production and the expression of iNOS and COX-2. Additionally, compound 2 effectively suppressed NF-κB nuclear translocation at a concentration of 40 µM.

Antimicrobial Potential of Natural Compounds of Zingiberaceae Plants and their Synthetic Analogues: A Scoping Review of In vitro and In silico Approaches.

AIMS: There has been increased scientific interest in bioactive compounds and their synthetic derivatives to promote the development of antimicrobial agents that could be used sustainably and overcome antibiotic resistance. METHODS: We conducted this scoping review to collect evidence related to the antimicrobial potential of diverse natural compounds from Zingiberaceae plants and their synthetic derivatives. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Extension for Scoping Reviews guidelines. The literature search was conducted using PubMed, Web of Science and Scopus electronic databases for relevant studies published from 2012 to 2023. A total of 28 scientific studies fulfilled the inclusion criteria. The authors of these studies implemented in vitro and in silico methods to examine the antimicrobial potency and underlying mechanisms of the investigated compounds. RESULT: The evidence elucidates the antimicrobial activity of natural secondary metabolites from Zingiberaceae species and their synthetic derivatives against a broad panel of gram-positive and gram-negative bacteria, fungi and viruses. CONCLUSION: To date, researchers have proposed the application of bioactive compounds derived from Zingiberaceae plants and their synthetic analogues as antimicrobial agents. Nevertheless, more investigations are required to ascertain their efficacy and to broaden their commercial applicability.

Influence of Thermal Treatment on the Composition of Alpinia officinarum Rhizome.

Alpinia officinarum is a representative of the Zingiberaceae family, which is known for its wide use in the food and pharmaceutical industries also due to its precious pharmacological potential. The major aim of the present study was to evaluate the influence of thermal treatment on the composition of the rhizome of Alpinia officinarum and its antioxidant activity. The fresh rhizome was subjected to various thermal treatment processes-boiling, frying and microwave heating during various time intervals-and their composition and antioxidant activity were determined using chromatographic (HPLC - High Performance Liquid Chromatography and HPLC-MS - High Performance Liquid Chromatography Mass Spectrometry) and spectrophotometric (DPPH and TPC - Total Phenolic Content) methods. Pinobanksin was the main compound found in the extract of the fresh rhizome (537.79 mg/kg), followed by galangin (197.7 mg/kg) and zingerone (185.5 mg/kg). The effect of thermal treatment on the rhizome composition was varied. In general, thermal processing significantly decreased the content of active compounds in the rhizome. However, there were some exceptions-boiling for 4 min significantly increased the content of pinobanksin (1162.4 mg/kg) and galangin (280.7 mg/kg), and microwave processing for 4 min increased the content of pinocembrin (213 mg/kg). It was found that boiling and microwave treatment significantly increased the antioxidant activity of the processed rhizomes.

Effect of Enoxaparin and Daikenchuto Coadministration on Hepatic Disorder Markers in Gynecological Cancer Patients after Abdominal Surgery.

Enoxaparin and daikenchuto are commonly administered to prevent venous thromboembolism and intestinal obstruction after gynecological malignancy surgery. However, the effects of their combined use on hepatic function are not well studied. This study aimed to clarify the effects of the coadministration of enoxaparin and daikenchuto on hepatic function. First, Japanese Adverse Drug Event Report (JADER) data were analyzed to identify signals of hepatic disorders. Second, a retrospective observational study of patients who underwent surgery for gynecological malignancies was conducted. This study defined hepatic disorders as an increase in aspartate aminotransferase (AST) or alanine aminotransaminase (ALT) levels above the reference values, using 1-h postoperative values as the baseline. The analysis of JADER data revealed an increased risk for hepatic disorders with the coadministration of enoxaparin and daikenchuto. An observational study also showed higher odds ratios (95% confidence intervals) for the occurrence of hepatic disorders in the coadministration group (4.27; 2.11-8.64) and enoxaparin alone group (2.48; 1.31-4.69) than in the daikenchuto alone group. The median increase in the ALT level was also higher in the coadministration group (34; 15-59) than in the enoxaparin alone (19; 6-38) and daikenchuto alone groups (8; 3-33). In conclusion, our study suggests that compared with the use of enoxaparin or daikenchuto alone, enoxaparin and daikenchuto coadministration increases the risk of hepatic disorders, with more significant increases in AST and ALT levels. Healthcare workers need to be aware of these potential side effects when combining these drugs after surgery for gynecological malignancies.

Anti-cancer potential of zerumbone in cancer and glioma: current trends and future perspectives.

Plant-derived immunomodulators and antitumor factors have appealed lots of attention from natural product scientists for their efficiency and safety and their important contribution to well-designed targeted drug action and delivery mechanisms. Zerumbone (ZER), the chief component of Zingiber zerumbet rhizomes, has been examined for its wide-spectrum in the treatment of multi-targeted diseases. The rhizomes have been used as food flavoring agents in numerous cuisines and in flora medication. Numerous in vivo and in vitro experiments have prepared confirmation of ZER as a potent immunomodulator as well as a potential anti-tumor agent. This review is an interesting compilation of all the important results of the research carried out to date to investigate the immunomodulatory and anticancer properties of ZER. The ultimate goal of this comprehensive review is to supply updated information and a crucial evaluation on ZER, including its chemistry and immunomodulating and antitumour properties, which may be of principal importance to supply a novel pathway for subsequent investigation to discover new agents to treat cancers and immune-related sickness. In addition, updated information on the toxicology of ZER has been summarized to support its safety profile.

Anti-inflammatory effects and related mechanisms in vitro and in vivo of Hedychium coccineum rhizome essential oil.

ETHNOPHARMACOLOGICAL RELEVANCE: Hedychium coccineum rhizome is an anti-inflammatory ethnomedicine used to remedy inflammation-related swelling and bronchial asthma. AIM OF THE STUDY: The study aimed to analyze the phytochemical constituents of H. coccineum rhizome essential oil (EO) and evaluate its in vitro and in vivo anti-inflammatory effects and underlying mechanisms. MATERIALS AND METHODS: Phytochemical constituents of H. coccineum rhizome EO were analyzed using GC-FID/MS. In RAW264.7 macrophages induced by LPS, blockade of PGE2, NO, IL-1ß, IL-6, and TNF-α secretion by H. coccineum rhizome EO was measured, and then Western blot, qRT-PCR, and immunofluorescent staining were used to evaluate its underlying mechanisms. Moreover, we used the xylene-induced ear edema model for testing anti-inflammatory potential in vivo and examined auricular swelling as well as tissue and serum contents of IL-1ß, IL-6, and TNF-α. RESULTS: EO's main components were E-nerolidol (40.5%), borneol acetate (24.8%), spathulenol (4.5%), linalool (3.8%), elemol (3.5%), and borneol (3.4%). In RAW264.7 cells stimulated by LPS, EO downregulated the expression of pro-inflammatory enzyme (iNOS and COX-2) genes and proteins, thereby suppressing pro-inflammatory mediators (NO and PGE2) secretion. Simultaneously, it reduced TNF-α, IL-1ß, and IL-6 release by downregulating their mRNA expression. Besides, H. coccineum EO attenuated LPS-stimulated activation of NF-κB (by reducing IκBα phosphorylation and degradation to inhibit NF-κB nuclear translocation) and MAPK (by downregulating JNK, p38, and ERK phosphorylation). In xylene-induced mouse ear edema, EO relieved auricular swelling and lowered serum and tissue levels of TNF-α, IL-1ß, and IL-6. CONCLUSIONS: H. coccineum EO had powerful in vivo and in vitro anti-inflammatory effects by inhibiting MAPK and NF-κB activation. Hence, H. coccineum EO should have great potential for application in the pharmaceutical field as a novel anti-inflammatory agent.

A new 3,4-seco-isopimarane and three new isopimarane diterpenoids from Kaempferia champasakensis collected from Vietnam and their cytotoxic activities.

A phytochemical investigation of Kaempferia champasakensis rhizomes led to the isolation of a new 3,4-seco-isopimarane diterpene, kaempferiol A (1), and three new isopimarane diterpenes, kaempferiols B-D (2-4), together with six known isopimarane diterpenes (5-10). The structures of 1-4 were elucidated by extensive spectroscopic analyses, including HR-ESI-MS, UV, IR, and 1D and 2D NMR. The absolute configurations of 1, 3, and 4 were determined by ECD calculations, while that of 2 was established using the modified Mosher method. All isolated compounds were tested for cytotoxicity against three human cancer cell lines, lung cancer (A549), cervical cancer (HeLa), and breast cancer (MCF-7). Among them, 6 and 7 showed moderate cytotoxic activities against the three tested cell lines, with IC50 values ranging from 38.04 to 27.77 µM, respectively.

Characterization of the Volatile Constituents of Plai (Zingiber purpureum) by Gas Chromatography-Mass Spectrometry.

Zingiber purpureum Roscoe, known as plai in Thailand, is a perennial plant of the Zingiberaceae family and has traditionally been used in Southeast Asian countries to treat inflammation, pain, and asthma. In this study, we performed the characterization of the volatile constituents in ethyl acetate extracts of plai. Ethyl acetate extracts derived from the rhizomes of plai were subjected to gas chromatography-mass spectrometry, and the key peaks in the total ion current chromatograms were annotated or identified. In total, twenty-one compounds were identified using isolation procedures or standards, and nine compounds were annotated by comparing their Kovats retention index (RI) and electron ionization (EI) mass spectra with those in the literature. Most of the identifications were inconsistent with the tentative annotations found via library search and suggested that some peaks were incorrectly assigned in previous studies. Thus, to avoid further misannotations and contribute to the research on dereplication, the RI value, EI mass spectral data, and NMR spectroscopy data of the isolated compounds are reported.

Phytochemical analysis and immunomodulatory activities in vitro and in vivo of Aframomum melegueta K Schum seed extracts.

Aframomum melegueta K Schum (A. melegueta), an herbaceous plant renowned for its medicinal seeds, was investigated for its potential immunomodulatory effects in vitro and in vivo using ethanolic and methanolic extracts. The immunomodulatory effect was evaluated by measuring antibody titers using the agglutination technique, while anti-inflammatory activity was assessed in a carrageenan-induced mouse paw edema model. In vitro immunomodulatory activity was measured by lysozyme release from neutrophils. Additionally, white blood cell counts were analyzed post-extracts treatment. The MTT assay was employed to determine cytotoxicity, and the biochemical parameters of liver toxicity were evaluated. Remarkably, both extracts exhibited a dose-dependent reduction in paw edema (p < 0.001), with the most significant reduction observed at 1 g/kg (78.13 and 74.27% for ethanolic and methanolic extracts, respectively). Neutrophil degranulation was significantly inhibited in a dose-dependent manner (p < 0.003), reaching maximal inhibition at 100 µg/mg (60.78 and 39.7% for ethanolic and methanolic extracts, respectively). In comparison to the control group, both antibody production and white blood cell counts were reduced. Neither of the extracts showcased any cytotoxicity or toxicity. These findings suggest that A. melegueta extracts exhibit immunosuppressive and anti-inflammatory activities due to the presence of various biomolecules.

Chemical Composition, Toxicity, and Repellency of Essential Oils from Three Hedychium Species Against Stored-Product Insects.

Stored products are constantly infested by insects, so finding eco-friendly bioinsecticides for insect management is important. The work aimed to assess the insecticidal and repellent activity of essential oil (EO) from Hedychium glabrum S. Q. Tong, Hedychium coronarium Koen., and Hedychium yunnanense Gagnep. against Tribolium castaneum, Lasioderma serricorne, and Liposcelis bostrychophila. Results showed that 88 chemical components were identified in the extracted Hedychium EOs, indicating that they exhibited diversity in components. According to principal component analysis (PCA), the composition of the EO from the H. yunnanense stem and leaf (EOHYSL) was significantly different from other EOs due to the different organs and species. The biological activity also varied continuously with plant species and organs. Only the EO of H. yunnanense (EOHY) showed strong fumigant toxicity. While in the contact tests, EOHGR showed the strongest toxicity effect on L. bostrychophila, with a LC50 value of 71.76 µg/cm2, which was closest to the positive control (Pyrethrin). All EOs had remarkable repellent activities against the three target insects, and repellency increased with concentration. According to the results of the comprehensive score, EOHY had the highest potential, which ranged from 0.7999 to 0.8689. Thus, Hedychium EOs possess potential biorational traits to be biological insecticides.

Genomic Insights into High-Altitude Adaptation: A Comparative Analysis of Roscoea alpina and R. purpurea in the Himalayas.

Environmental stress at high altitudes drives the development of distinct adaptive mechanisms in plants. However, studies exploring the genetic adaptive mechanisms of high-altitude plant species are scarce. In the present study, we explored the high-altitude adaptive mechanisms of plants in the Himalayas through whole-genome resequencing. We studied two widespread members of the Himalayan endemic alpine genus Roscoea (Zingiberaceae): R. alpina (a selfing species) and R. purpurea (an outcrossing species). These species are distributed widely in the Himalayas with distinct non-overlapping altitude distributions; R. alpina is distributed at higher elevations, and R. purpurea occurs at lower elevations. Compared to R. purpurea, R. alpina exhibited higher levels of linkage disequilibrium, Tajima's D, and inbreeding coefficient, as well as lower recombination rates and genetic diversity. Approximately 96.3% of the genes in the reference genome underwent significant genetic divergence (FST ≥ 0.25). We reported 58 completely divergent genes (FST = 1), of which only 17 genes were annotated with specific functions. The functions of these genes were primarily related to adapting to the specific characteristics of high-altitude environments. Our findings provide novel insights into how evolutionary innovations promote the adaptation of mountain alpine species to high altitudes and harsh habitats.

Total Synthesis of (-)-Amovillosumin A and Structure Correction of (-)-Amovillosumin C Using Chemical Synthesis.

Norlignans are a rare class of natural products isolated from a diverse range of plant species, many of which have interesting biological activities including antibacterial, antioxidant, phytotoxic, platelet aggregation inhibitory effects, and more. Isolated from Amomum villosum (Amomi Fructus), amovillosumins A (1) and C (3) are norlignans which were of interest to synthesize, due to their interesting bioactivities, specifically their ability to increase stimulation of glucagon-like peptide-1 (GLP-1) secretion. In this research, key intermediate 15 was used to stereoselectively synthesize (7R,8R)-amovillosumins A (1) and C (3). The developed method includes a Mitsunobu coupling, a modified rhodium-catalyzed Miyaura arylation, and an acid-catalyzed cyclization in key bond-forming steps. After synthesis, the structure of 1 was confirmed, but it was revealed that the benzodioxane-containing structure of amovillosumin C (3) that had been proposed in the literature was incorrect. Thus, with further investigation a structure correction of 3 was achieved by synthesis, the correct structure being 8-O-4'-oxynorlignan.

Antimicrobial and Antiproliferative Effects of Zingiberaceae Oils: A Natural Solution for Oral Health.

Essential oils have been recognised for their potential benefits in oral care. The aim of this study was to evaluate the antibacterial and antiproliferative activity of essential oils derived from four Zingiberaceae species. A combination of GC/MS and GC-FID was employed to analyse these essential oils. The results showed that ß-myrcene (79.77 %) followed by ethyl-cinnamate (40.14 %), ß-curcumene (34.90 %), and alloaromadendrene (25.15 %) as the primary constituents of Curcuma mangga, Curcuma xanthorrhiza, Kaempferia galanga and Curcuma aeruginosa, respectively. The Zingiberaceae oils were tested for their antibacterial activity against oral bacteria using the disc diffusion test. Curcuma xanthorrhiza oil showed the largest inhibition zones against Streptococcus mitis (19.50±2.22 mm) and Streptococcus sanguinis (15.04±3.05 mm). Similarly, Curcuma mangga oil exhibited significant antibacterial activity against Streptococcus mutans (12.55±0.45 mm) and mixed oral bacteria (15.03±3.82 mm). Furthermore, the MTT viability assay revealed moderate inhibitory activity of these essential oils against H103 and ORL-204 oral cancer cells. The study findings demonstrate that Curcuma xanthorrhiza and Curcuma mangga essential oils have potent antibacterial properties, suggesting their potential use as natural alternatives to synthetic antibacterial agents in oral care products. However, further investigations are necessary to fully explore their therapeutic applications.

Comparative analyses reveal a phenylalanine ammonia lyase dependent and salicylic acid mediated host resistance in Zingiber zerumbet against the necrotrophic soft rot pathogen Pythium myriotylum.

Little is known about the molecular basis of host defense in resistant wild species Zingiber zerumbet (L.) Smith against the soil-borne, necrotrophic oomycete pathogen Pythium myriotylum Drechsler, which causes the devastating soft rot disease in the spice crop ginger (Zingiber officinale Roscoe). We investigated the pattern of host defense between Z. zerumbet and ginger in response to P. myriotylum inoculation. Analysis of gene expression microarray data revealed enrichment of phenylpropanoid biosynthetic genes, particularly lignin biosynthesis genes, in pathogen-inoculated Z. zerumbet compared to ginger. RT-qPCR analysis showed the robust activation of phenylpropanoid biosynthesis genes in Z. zerumbet, including the core genes PAL, C4H, 4CL, and the monolignol biosynthesis and polymerization genes such as CCR, CAD, C3H, CCoAOMT, F5H, COMT, and LAC. Additionally, Z. zerumbet exhibited the accumulation of the phenolic acids including p-coumaric acid, sinapic acid, and ferulic acid that are characteristic of the cell walls of commelinoid monocots like Zingiberaceae and are involved in cell wall strengthening by cross linking with lignin. Z. zerumbet also had higher total lignin and total phenolics content compared to pathogen-inoculated ginger. Phloroglucinol staining revealed the enhanced fortification of cell walls in Z. zerumbet, specifically in xylem vessels and surrounding cells. The trypan blue staining indicated inhibition of pathogen growth in Z. zerumbet at the first leaf whorl, while ginger showed complete colonization of the pith within 36 h post inoculation (hpi). Accumulation of salicylic acid (SA) and induction of SA regulator NPR1 and the signaling marker PR1 were observed in Z. zerumbet. Silencing of PAL in Z. zerumbet through VIGS suppressed downstream genes, leading to reduced phenylpropanoid accumulation and SA level, resulting in the susceptibility of plants to P. myriotylum. These findings highlight the essential role of PAL-dependent mechanisms in resistance against P. myriotylum in Z. zerumbet. Moreover, our results suggest an unconventional role for SA in mediating host resistance against a necrotroph. Targeting the phenylpropanoid pathway could be a promising strategy for the effective management of P. myriotylum in ginger.

Potent anti-angiogenic component in Kaempferia galanga L. and its mechanism of action.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditionally, the roots of Kaempferia galanga has been used to treat high blood pressure, chest pain, headache, toothache, rheumatism, indigestion, cough, inflammation and cancer in Asia. Nevertheless, most of its pharmacological studies were focused on ethanolic extracts and volatile oils. The exact active chemical constituents and their underlying mechanisms are still poorly understood, especially towards its anti-cancer treatment. Inhibition of angiogenesis is an important atrategy to inhibit tumor growth. It has been reported that the low polar component of the plant possessed anti-angiogenic activity. Yet, the potent compound which is responsible for the effect and its molecular mechanism has not been reported. AIM OF THE STUDY: To determine the potent anti-angiogenic component in K.galanga and its mechanism of action. MATERIAL AND METHODS: The low polar components of the plant were concentrated using the methods of supercritical fluid extraction (SFE), subcritical extraction (SCE) and steam distillation (SD). The anti-angiogenic activity of the three extracts was evaluated using a zebrafish model. The content of the active compound in those extracts was determined with HPLC analysis. The in-vitro and in-vivo activity of the isolated compound was evaluated using human umbilical vein endothelial cells (HUVECs) model, the aortic ring assay and the matrigel plug assay, respectively. Its molecular mechanism was further studied by the western blotting assay and computer-docking experiments. Besides, its cytotoxicity on cancer and normal cell lines was evaluated using the cell-counting kit. RESULTS: HPLC results showed that trans-ethyl p-methoxycinnamate (TEM) was the major component of the extracts. The extract of SFE showed the best effect as it has the highest content of TEM. TEM could inhibit vascular endothelial growth factor (VEGF)-induced viability, migration, invasion and tube formation in human umbilical vein endothelial cells (HUVECs) in vitro. Moreover, it inhibited VEGF-induced sprout formation ex vivo and vessel formation in vivo. Mechanistic study showed that it could suppress tyrosine kinase activity of the receptor of VEGF (VEGFR2) and alter its downstream signaling pathways. In addition, the molecular docking showed that the binding of TEM and VEGFR2 is stable, which mainly attributed to the non-covalent binding interaction. Beside, TEM possessed little toxicity to both cancer and normal cells. CONCLUSION: TEM is the major anti-angiogenic component present in K. galanga and its anti-angiogenic property rather than toxicity provides scientific basis for the traditional use of K. galanga in cancer treatment.