BMC Chemistry最新文献

Marine microalgae rich in high-quality proteins are highly favored in the development of bioactive peptides. However, the scarcity of effective preparation methods still limits its application in healthy improvement. This study aimed to search for the effective natural antioxidative peptides from the microalga Porphyridium cruentum (P. cruentum) for protection skin cells against chronic oxidative stress by UPLC-Q-Exactive MS identification coupled to in silico prospection. An antioxidative dipeptide Threonyltyrosine (TY) was identified among 425 peptides. The in vitro antioxidant capacity of TY was slightly higher than that of vitamin C in ABTS radical scavenging assays with an IC₅₀ of (11.37 ± 1.32) ×10³ µg/L. The significant protective role of TY against paraquat-induced cytotoxicity in human keratinocyte (HaCaT) cells was observed in cell viability (+ 10.1%, P < 0.001), MDA (- 23.6%, P < 0.0001) levels, and enzyme activities, i.e., superoxide dismutase (SOD, + 17.1%, P < 0.001) and catalase (CAT, + 20.5%, P < 0.001). TY showed a dose-dependent effect (30-100 µg/mL) in upregulating the proliferative activity of paraquat-injured HaCaT cells.In addition, TY stable binding to the Kelch domain of Keap1 (ΔG = -5.13 kcal/mol) was analyzed via molecular docking and molecular dynamics simulations, which gave some clues on the potential activating Nrf2. Totally, TY exhibited a dual mechanism of free radical scavenging and antioxidant enzymes activation. These findings advanced our understanding of TY's development, properties and provide a foundation for future mechanistic investigations.

Dental caries is a disease of tooth tissue that can lead to complications, with Enterococcus faecalis being one of the Gram-positive bacteria that plays a crucial role in the infection process. Red betel leaves (Piper crocatum Ruiz & Pav.) are known to contain various phytochemicals; however, the antibacterial potential of Crocatin A, one of its isolated compounds, against E. faecalis and its molecular targets has not been previously reported. This study hypothesized that Crocatin A exhibits antibacterial activity against E. faecalis and has the potential to inhibit DNA gyrase B and DNA ligase, which are essential enzymes in DNA replication. Crocatin A was isolated from P. crocatum via column chromatography and characterized using infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and mass spectrometry. In vitro assays were carried out using the Kirby-Bauer disk diffusion method at concentrations of 1, 2, and 5%, as well as the microdilution method. Antibacterial activity was further analyzed in silico to predict binding affinity toward DNA gyrase B and DNA ligase, along with the evaluation of ADMET properties. The results demonstrated that Crocatin A produced concentration-dependent inhibition zones and exhibited a minimum inhibitory concentration (MIC) of 1250 µg/mL. In silico studies revealed binding energies of -6.34 kcal/mol for DNA gyrase B and - 5.77 kcal/mol for DNA ligase. In summary, Crocatin A showed moderate inhibition zones in vitro, although its MIC and MBC activities remain weak. In silico screening suggested possible binding interactions with DNA gyrase B and DNA ligase. Given the preliminary nature of these findings and the methodological limitations of the study, further validation is required to confirm its antibacterial potential.

Industrial production of Steamed Panax notoginseng (SPN) faces batch-to-batch variability (RSD > 15%) in rare G-Rk₃, G-Rh₄, 20(S) G-Rg₃, and 20(R) G-Rg₃ and costly quality control due to expensive reference standards (e.g., 20(S) G-Rg₃ ≈ $2,500 per 5 mg sample). To address this, we developed an integrated strategy: (1) A "Water Activation-Gradient Temperature Control" process optimized via orthogonal design and Arrhenius kinetics (Ea = 58.3 kJ/mol) increased total rare ginsenosides by 78.6% (32.7 mg/g, p < 0.01) under the following optimized parameters: particle size of 2-4 mm, water impregnation of 100% w/w for 2 h, and steaming at 120 °C for 5 h. This optimization reduced batch variability to an RSD < 5%; (2) An HPLC-QAMS method using accessible 20(R) G-Rg₃ as an internal reference achieved simultaneous quantification of four ginsenosides with validated relative correction factors (G-Rk₃: 0.7331, G-Rh₄: 0.5015, 20(S) G-Rg₃: 1.0777; RSD < 2.0%), demonstrating high accuracy (recovery: 91.95-101.34%, RSD < 1.8%), linearity (R² = 1.000), and robustness across HPLC systems (RSD < 3.5%), reducing reference standard costs by 75%. The Single-Marker Quantification (QAMS) method exhibited superior Analysis of greenness (AGREE) (score: 0.76 vs. 0.63 for ESM) and Blue Applicability Grade Index (BAGI) (score: 77.5 vs. 65.0 for ESM). Analysis of 15 batches confirmed consistency (RE% < 5% vs. ESM), while optimized extraction (60% ethanol, 5 cycles × 1.5 h) achieved 85.82% transfer rate for 20(R) G-Rg₃. This work resolves SPN industrialization bottlenecks by ensuring bioactive consistency and establishing a cost-effective, eco-friendly quality control model transferable to other processed botanicals.

For pest control, the use of botanical insecticides can be an effective alternative to synthetic insecticides. The objective of this study is to analyze the chemical composition and evaluate the insecticidal potential of B. antidysenterica stem bark extract as a natural alternative for controlling maize weevils. A fractionated extract was obtained by macerating and soaking the stem bark powder in n-hexane (1.36 ± 0.81%), chloroform (1.26 ± 0.43%), ethyl acetate (1.03 ± 0.47%), acetone (2.24 ± 0.75%), ethanol (3.01 ± 0.26%), and methanol (2.1 ± 0.9). The experimental tests for the insecticidal potential of each crude extract were conducted at different concentrations (0.025, 0.05, and 0.1 g/mL) on adult maize weevils to investigate the mortality rate, seed damage, and grain weight loss using contact bioassay method. The experiment was conducted in a completely randomized design with three replications. The data were analyzed using two-way ANOVA with the Tukey test for mean comparison. After 72 h, all extracts demonstrated high insect mortality while concurrently reducing grain damage and weight loss. However, ethanolic extract was the most effective at 0.1 g/mL with insect mortality (79 ± 1%), grain damage (18 ± 041%), and weight loss (21.6 ± 11%). GC-MS analysis of the ethanol extract identified forty-one compounds, mainly fatty acid esters, other esters, phenols, alkenes, and terpenoids. The presence of these bioactive compounds contributed to its strong insecticidal activity. Overall, the findings highlight the potential of B. antidysenterica ethanol extract as a promising natural alternative to synthetic insecticides.

The sucking pests such as aphids, planthoppers, and whiteflies pose a significant threat to global crop productivity, causing estimated losses of up to 40% in affected areas. Reports indicate that resistance to traditional agents such as imidacloprid has increased by more than 50% over the last decade, underscoring the urgency for innovative solutions. Neonicotinoids, which target insect nicotinic acetylcholine receptors (nAChRs), remain a vital component of pest management, offering an important alternative. Flupyrimin, a pyridylamide-type neonicotinoid with a unique mode of action on insect nAChRs, exhibits strong efficacy against resistant pest populations. In this study, a synthetic route to Flupyrimin was established, and the design and preparation of ten structural analogs were carried out. In these analogs, the trifluoroacetyl group was replaced by pyridylcarbamoyl moieties, and the pyridine ring was further derivatized. The synthetic strategy utilizes mild, non-hazardous solvents and high-efficiency reaction conditions, thus providing a practical and scalable approach for the generation of this novel class of compounds. Bioassays against Lipaphis erysimi (200 mg/L) demonstrated that compounds IIIa and IIIc exhibited mortality rates in excess of 45%, while IIIb exhibited a mortality rate that exceeded 65% mortality. Molecular docking simulation indicated that IIIb exhibited the strongest binding to insect nAChRs, supported by favorable hydrogen-bonding and π-π interactions. Conversely, fluorine substitution at the 3-position in IIIc resulted in a slight deviation in binding orientation and a reduction in affinity. Furthermore, the larger chlorine atom in IIId introduced steric hindrance that prevented optimal binding. Single-crystal X-ray analysis of IIIe confirmed its structure and conformation. These results suggest that pyridylamide-based neonicotinoids may serve as a valuable scaffold for the development of next-generation insecticidal agents. The distinct structural features of these receptors are distinct, and their predicted binding modes suggest the potential for different receptor interactions. This has the potential to provide avenues for future resistance-management strategies.

Background: Symmetrical (s-) triazine herbicides are the most commonly used pesticides, which frequently leave pesticide residues in food and environmental samples. Due to their carcinogenic and endocrine-disrupting properties, monitoring s-triazine herbicide residues in the water and food samples has become a critical concern of environmental and public health protection. Furthermore, there is no reported study on the application of salting-out assisted liquid-liquid extraction (SALLE) for simultaneous extraction of chloro-s-triazines and their major degradation products from environmental water and fruit samples. Therefore, SALLE method was developed for the simultaneous extraction of chloro-s-triazine pesticides and their degradation products from diverse samples by HPLC-DAD.

Methods: In the present study, SALLE method based on binary salts was developed for the simultaneous extraction of multi-residue chloro-s-triazine pesticides, including (atrazine, cyanazine, and simazine), with their degradation products (deethylatrazine and deisopropylatrazine) from environmental water and fruit samples prior to analysis by HPLC-DAD. Various parameters that can affect the method, such as extraction solvent type and volume, type, mass and ratio of salts and pH effect, centrifugation and vortexing times were successfully optimized.

Results: The developed method provided good linearity with coefficients of regression in the range of 0.991-0.997, under the optimized conditions. The method demonstrated lower limit of detection and limit of quantification in the range of 0.002-0.089 and 0.0066-0.299 µg/L, respectively. Repeatability and reproducibility in terms of %RSD were found in the range of 2.15-7.13% and 3.28-8.95%, respectively. The mean recovery was varied from 74.06 to 109.90% with RSD (n = 3) below 10% for all samples studied.

Conclusion: The developed method has been successfully applied for the trace level extraction of pesticide residues and their degradation products in real samples, including environmental waters, and fruit samples. Hence, the developed method can be used as a selective and green alternative for the extraction of pesticide residues in water, fruits and other contaminated food samples.

In this study, waste polyethylene terephthalate (PET) from discarded bottles was recycled via KOH treatment to produce activated carbon (AC) to remove methylene blue (MB) and picric acid (PA) from contaminated water. The AC produced was characterized by using physicochemical methods to assess its surface porosity, morphology and function groups. Batch adsorption experiments were performed the impact of pH, sorbent amount, time, sample volume, and initial concentration of the target dye on the adsorption efficiency. Adsorption followed the Langmuir isotherm model indicating monolayer adsorption behavior, while kinetics fitted with the pseudo-second-order model. The prepared AC exhibited high maximum adsorption capacities reached 334.4 mg g⁻¹ for MB and 271.7 mg g⁻¹ for PA. Quantitative dye desorption (> 97% recovery) was achieved using H₂SO₄ for MB and NaOH for PA. The method was also applied to spectrophotometric quantification of both analytes, yielding linear calibration curves for MB (0.15-5.76 mg L⁻¹, R² = 0.9997) and PA (0.01-1.68 mg L⁻¹, R² = 0.9980). Detection limits were 0.04 mg L⁻¹ (MB) and 0.003 mg L⁻¹ (PA), with quantification limits of 0.15 mg L⁻¹ (MB) and 0.013 mg L⁻¹ (PA). Successful application to diverse water samples confirmed the method's efficacy for dye removal and quantification.