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Cleistocalyx operculatus flower buds have been widely used in traditional medicine because of their rich content of bioactive constituents. In this study, we obtained seven solvent extracts from the flower buds and evaluated their total phenolic (TPC), flavonoid (TFC), tannin (TTC), triterpenoid saponin (TSC), and alkaloid (TAC) con­tents. We assessed antioxidant activities using the DPPH assay and also looked at antimicrobial and enzyme in­hibi­tory effects. The water extract possessed the highest TPC (328.9 mg GAE/g extract), followed by ethanol, me­thanol, and hexane extracts (85.4–101.5 mg GAE/g extract). Chloroform, butanol, ethyl acetate, and ethanol extracts had high TSCs (245.4–287.2 mg OAE/g extract). The hexane extract was richest in TTC and TFC (32.7 mg CE/g extract and 81.1 mg QE/g extract, respectively). Ethanol and methanol extracts exhibited the strongest antioxidant activities (IC50 values of 25.2 and 30.3 μg/ml, respectively), followed by the water extract (IC50 of 40.2 μg/ml). The hexane extract displayed the most growth-inhibitory activity against Helicobacter pylori ATCC51932 and ATCC43504 strains and Salmonella enterica serovar Typhimurium ATCC13311 (MIC values of 0.06, 0.13, and 0.4 mg/ml, respectively). Moreover, the hexane extract revealed the strongest inhibition of H. pylori urease acti­vity (IC50 of 4.51 μg/ml), whereas the water and methanol extracts had potent inhibitory effects on α-glucosidase activity (IC50 values of 9.9 and 15.1 μg/ml, respectively). These flower bud extracts could be used for health pro­tection, especially in preventing bacterial infections and inhibiting enzymes associated with various human dis­eases. Further investigation into the application of C. operculatus flower buds in the food and pharmaceutical industries is necessary.

Six solvent fractions isolated from flower bud and leaf ethanolic extracts of Cleistocalyx operculatus were analyzed for their phytochemical contents, including phenolics, flavonoids, saponins, tannins, and alkaloids. Antioxidant activities were measured using the ABTS, DPPH, and FRAP assays. The results showed that the flower bud aqueous fraction (BAF) and the leaf aqueous fraction (LAF) rich in phenolic content (768.18 and 490.74 mg GAE/g dry extract, respectively) exhibited significantly higher antioxidant activities than the other fractions. The flower bud hexane fraction (BHF) had remarkably high flavonoid and saponin contents (134.77 mg QE/g and 153.33 mg OA/g dry extract, respectively), followed by that of the leaf hexane fraction (LHF) (76.54 mg QE/g and 88.25 mg OA/g dry extract, respectively). The BHF and LHF were found to have extremely high antibacterial activity against two H. pylori strains, ATCC 51932 and 43504 (MICs of 125 µg/mL). Interestingly, DMC (2′,4′-Dihydroxy-6′-methoxy-3′,5′-dimethylchalcone) isolated from the BHF displayed greater antibacterial activity against the bacterial strains (MICs of 25–50 µg/mL) than those of the fractions. In addition, DMC presented potent inhibitory effects on H. pylori urease (IC50 of 3.2 µg/mL) and α-amylase (IC50 of 83.80 µg/mL), but no inhibition against α-glucosidase. It was also demonstrated that DMC showed pronounced inhibitory effects on the urease activity and biofilm formation of H. pylori, and could increase the membrane permeability of the bacterial cells. Scanning electron micrographs depicted that the BHF and DMC had strong effects on the cell shape and significantly induced the distortion and damage of the cell membrane. The fractions and DMC showed no significant toxicity to four tested human cell lines. Efforts to reduce antibiotic use indicate the need for further studies of the flower buds and DMC as potential products to prevent or treat gastric H. pylori infections.

From an ethyl acetate extract of the barks of Chukrasia tabularis, three compounds including one limonoid (tabularisin A), one flavonoid (quercetin), and one coumarin (scopoletin) were isolated by chromatographic methods. Their structures were comfirmed by analysis of spectroscopic data (ESI-MS, 1H-NMR, 13C-NMR, DEPT, HMBC, HSQC và COSY) and by comparison with the literature reports.

Background: Non-invasive multi-cancer early detection (MCED) tests have shown promise in enhancing early cancer detection. However, their clinical utility across diverse populations remains underexplored, limiting their routine implementation. This study aims to validate the clinical utility of a multimodal non-invasive circulating tumor DNA (ctDNA)-based MCED test, SPOT-MAS (Screening for the Presence Of Tumor by DNA Methylation And Size). Methods: We conducted a multicenter prospective study, K-DETEK (ClinicalTrials.gov identifier: NCT05227261), involving 9057 asymptomatic individuals aged 40 years or older across 75 major hospitals and one research institute in Vietnam. Participants were followed for 12 months. Results: Of the 9024 eligible participants, 43 (0.48%) tested positive for ctDNA. Among these, 17 were confirmed with malignant lesions in various primary organs through standard-of-care (SOC) imaging and biopsy, with 9 cases matching our tissue of origin (TOO) predictions. This resulted in a positive predictive value of 39.53% (95%CI 26.37–54.42) and a TOO accuracy of 52.94% (95%CI 30.96–73.83). Among the 8981 participants (99.52%) who tested negative, 8974 were confirmed cancer-free during a 12-month period after testing, yielding a negative predictive value of 99.92% (95% CI 99.84–99.96). The test demonstrated an overall sensitivity of 70.83% (95%CI 50.83–85.09) and a specificity of 99.71% (95% CI 99.58–99.80) for detecting various cancer types, including those without SOC screening options. Conclusions: This study presents a prospective validation of a multi-cancer early detection (MCED) test conducted in a lower middle-income country, demonstrating the potential of SPOT-MAS for early cancer detection. Our findings indicate that MCED tests could be valuable additions to national cancer screening programs, particularly in regions where such initiatives are currently limited. Trial registration: ClinicalTrials.gov ID: NCT05227261. Date of registration: 07/02/2022. [ABSTRACT FROM AUTHOR]

Alpinia nelumboides Nob.Tanaka, T.T.K.Van & V.Hoang is the new Alpninia species discovered in Vietnam in 2023. Herein, we first hydrodistillated its pseudo-stems and rhizomes to obtain its essential oils, PS-EO and RH-EO. Their volatile compounds and total polyphenols were analysed by gas chromatography-mass spectrometry and the Folin-Ciocalteu method, respectively. Antioxidant activities were determined using four different approaches. The results showed that PS-EO and RH-EO contained 40 and 31 compounds, accounting for 99.78% and 99.45% of their compositions, respectively. The contents of polyphenols and monoterpenes in PS-EO were higher than in RH-EO. RH-EO displayed weaker scavenging activities (17.40–19.53%) than PS-EO (30.81–44.08%). PS-EO also showed higher ferric and cupric reducing powers, with EC50 values of 3.50–5.30 mg/mL smaller than RH-EO's EC50 values of 19.0–23.0 mg/mL. These results first revealed the phytochemical profile and antioxidant activities of EOs from A. nelumboides. [ABSTRACT FROM AUTHOR]

Aim: Cancers lacking standard screening (LSS) options account for approximately 70% of cancer-related deaths due to late-stage diagnosis. Circulating tumor DNA (ctDNA) is a promising biomarker for multi-cancer early detection. We previously developed SPOT-MAS, a multimodal ctDNA-based assay analyzing methylation and fragmentomic profiles, effective in detecting common cancers (breast, colorectal, liver, lung and gastric). This study extends the analysis to five LSS cancers: endometrial, esophageal, head and neck, ovarian and pancreatic. Methods: SPOT-MAS was applied to profile cfDNA methylation and fragmentomic patterns in 739 healthy individuals and 135 LSS cancer patients. Results: We identified 347 differentially methylated regions and observed genome-wide hypomethylation across all five LSS cancers. Esophageal and head and neck cancers showed an enrichment of short cfDNA fragments (<150 bp). Eleven 4-mer end motifs were consistently altered in cfDNA fragments across all LSS cancers. Many significant signatures were consistent with previous observations in common cancers. Notably, SPOT-MAS achieved 96.2% specificity and 74.8% overall sensitivity, with a lower sensitivity of 60.7% in early-stage cancers. Conclusion: This proof-of-concept study demonstrates that SPOT-MAS a non-invasive test trained on five common cancer types, could detect a number of LSS cancer cases, potentially complementing existing screening programs. Plain Language Summary Many cancers do not have standard tests, so they are often found too late, which leads to about 70% of cancer deaths. We've created a blood test that can help find cancer early. This test has already worked well for common cancers like breast and lung cancer, and now we're testing it on five harder-to-detect cancers: endometrial, esophageal, head and neck, ovarian and pancreatic cancers. In our study, we tested our blood test on 739 healthy people and 135 patients with these difficult cancers. Our method correctly identified healthy people 96.2% of the time and found cancer cases 74.8% of the time. This new test could help with screening for types of cancer that do not have good tests right now. Article highlights Approximately 70% of cancer deaths result from late-stage diagnoses in cancers lacking standard-of-care screening (LSS). The SPOT-MAS test is a ctDNA-based assay designed to detect five common cancers (breast, lung, colorectal, gastric and liver) and has been extended to five additional LSS cancers: endometrial, esophageal, head and neck, ovarian and pancreatic. The assay analyzed cfDNA methylation and fragmentomic patterns in 135 LSS cancer patients and 739 healthy individuals. It identified 347 differentially methylated regions and specific fragmentomic alterations. SPOT-MAS achieved 96.2% specificity and 74.8% overall sensitivity, with 60.7% sensitivity for early-stage detection. This study suggests that SPOT-MAS could serve as a non-invasive method for detecting LSS cancers. [ABSTRACT FROM AUTHOR]

The type of material employed in crankshaft production has a great influence on the performance, durability, and product lifespan. There are many types of material that can be used to manufacture crankshafts, but choosing the best one is a complicated work. This study is carried out to select the best material type among four commonly deployed types, including 1080 steel, 18CrMo4 steel, 4130 steel, and S48C steel. Fifteen parameters (criteria) were chosen to describe each material. The weights of the criteria were determined by three methods, including the Mean weight method, the Entropy weight method, and the MEREC (Method based on the Removal Effects of Criteria) weight method. To rank the steel types, the PIV (Proximity Indexed Value) method was adopted, and it was demonstrated that the ranks did not depend on the weighting method followed. S48C is the best choice among the four types of steel generally utilized for crankshaft production. [ABSTRACT FROM AUTHOR]

The Zingiber genus has been widely applied in food and pharmaceuticals due to its varied chemical composition and significant benefits. Zingiber plicatum Škorničk. & Q.B. Nguyễn was described in Vietnam in 2015, yet there has been no report on its phytochemicals and bioactivity. In this study, we first analyzed the chemical composition of essential oil and its antioxidant activities. Isolation of the rhizome essential oil was performed through hydrodistillation using a Clevenger apparatus for 3.5 h, then volatile compositions were determined using gas chromatography-mass spectroscopy (GC-MS). Additionally, the antioxidant activities were assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric reducing power assays. The GC-MS analysis showed a total of 54 volatile components, mainly belonging to monoterpene hydrocarbons (57.69%) and sesquiterpene hydrocarbons (28.98%). The main compounds were β-pinene (26.85%), α-pinene (11.73%), limonene (10.03%), and germacrene D (5.26%). The essential oil also showed antioxidant activities, with an IC50 of 84.53 mg/mL for DPPH scavenging activity and an EC50 of 17.3 mg/mL for ferric reducing power. These findings first provided data on the chemical components and antioxidant properties of Z. plicatum essential oil. [ABSTRACT FROM AUTHOR]

Litsea mekongensis Lecomte is a native species that originated in Vietnam and Laos. To date, the volatile components and antibacterial activity of the essential oils derived from L. mekongensis leaves have not yet been reported. This study aims to investigate the chemical composition and antibacterial activity of L. mekongensis leaf essential oil. The chemical constituents were analyzed by gas chromatography-mass spectroscopy (GC-MS), and the antibacterial activity was evaluated using the agar well diffusion method. The GC-MS analysis showed that fifty-four volatile components were detected, of which sesquiterpene hydrocarbons accounted for almost 65% of the total, while the proportion of monoterpene hydrocarbons was 19.84%. Germacrene D (16.17%), γ-elemene (7.82%), β-phellandrene (6.76%), α-pinene (6.62%), and δ-cadinene (5.68%) were identified as major components. The essential oil exhibited strong antibacterial activity against Salmonella typhi, Staphylococcus aureus, and Escherichia coli. S. aureus was the most sensitive species, but no inhibitory activity against Pseudomonas aeruginosa was recorded. These findings revealed information on the chemical constituents of the essential oil prepared from L. mekongensis and its potential antibacterial activity against several pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Viola dalatensis, belonging to the Violaceae family, is an endemic species to Vietnam. The present study aimed to determine phenolic compounds in extracts from aerial parts of the plant species using high performance liquid chromatography with diode-array detection (HPLC-DAD). In addition, free radical scavenging and bovine albumin denaturation inhibition assays were performed to evaluate the antioxidant and in vitro anti-inflammatory activities of the extracts. Most of the phenolic compounds in the methanolic extract were detected at the greatest concentrations compared to the other extracts, which was also supported by the highest total phenolic content (26.70 ± 0.1059 mg GAE/g). In general, the antioxidant activities of the methanolic and ethanolic extracts were found to be stronger than those of the other extracts. The aqueous extract exhibited the most potent inhibitory effect on albumin denaturation (IC50 = 90.39 ± 8.415 µg/mL), comparable with that of diclofenac. Through principal component analysis, 88.60% of the total variance in the phenolic dataset was explained. The correlation analysis showed that chlorogenic acid, ferulic acid, epigallocatechin gallate, rutin, and kaempferol may play important roles in antioxidant activity while gallic acid could contribute to in vitro anti-inflammatory activity of the extracts. The findings of this study provide the first evidence of the bioactive compounds present in V. dalatensis and shed light on the potential health-promoting properties linked to its aerial parts. [ABSTRACT FROM AUTHOR]