Search Results (302)

Barley malt residue (BMR) was subjected to microwave-assisted enzymatic hydrolysis to evaluate its potential as a raw material to produce xylooligosaccharides (XOS) suitable for use as a prebiotic. The influent factors on XOS production, microwave power, exposure time, and xylanase dosage were ascertained with response surface methodology based on Box–Behnken design (BBD). The fitted models of XOS and xylose yields were in good agreement with the experimental results. Using a microwave power of 1235.1 W, a 6 min exposure time, and a xylanase concentration of 89.12 U/g substrate gave the highest yield of XOS: 208.05 mg/g substrate at 4 h of enzyme incubation time. Based on the product composition, BMR-XOS purification by Saccharomyces cerevisiae treatment was superior to the process of activated carbon adsorption and ethanol precipitation treatment and was selected for further experiments. Thin-Layer Chromatography (TLC) and high-performance liquid chromatography (HPLC) clearly elucidated the oligosaccharide compositions, and the result of Fourier Transform Infrared Spectroscopy (FTIR) confirms the molecular structure and sugar components of achieved BMR-XOS. In vitro fermentation of BMR-XOS obtained from this study by the selected probiotics, Lactococcus lactis TISTR 1401, Levicaseibacillus brevis FS 2.1, Lactobacillus casei TISTR 1463, showed similar prebiotic activity compared with the commercial XOS, galactooligosaccharides (GOS), xylose, and glucose (control). In conclusion, the present study was successful in establishing the use of barley malt residue for the extraction of xylan and XOS, which could be further used as a prebiotic. Full article

Background/Objectives: The rise in antibiotic-resistant ESKAPE pathogens, which are responsible for severe and hard-to-treat infections, highlights the urgent need for alternative therapeutic agents. While species in the Leonotis genus have demonstrated antimicrobial potential, limited research exists on Leonotis ocymifolia. This study evaluated the phytochemical profiles and antioxidant, antibacterial, and antibiofilm activities of L. ocymifolia leaf and stem extracts. Methods: Acidified acetone and hexane were used for extraction, followed by liquid–liquid fractionation with dichloromethane (DCM), ethyl acetate, and butanol. Phytochemicals were profiled using thin-layer chromatography (TLC), while polyphenolic content and antioxidant activity were determined using colorimetric and DPPH assays, respectively. Antibacterial activity was assessed via bioautography and micro-broth dilution assays. Antibiofilm activities were evaluated using crystal violet staining, and metabolic activity was assessed using tetrazolium salt as a cell viability indicator. Results: Ethyl acetate fractions had the highest phenolic (98.15 ± 9.63 mg GAE/g) and tannin contents (108.28 ± 8.78 mg GAE/g), with strong DPPH scavenging activity (79–90% at 250 µg/mL). DCM extracts had potent antibacterial activity, with a minimum inhibitory concentration (MIC) of 0.31–0.625 mg/mL against Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae. Antibiofilm assays revealed over 50% inhibition across biofilm formation phases, with DCM leaf extracts disrupting biofilms by inhibiting microbial metabolism. Conclusions: This study highlights L. ocymifolia as a promising source of bioactive compounds with significant antioxidant and antibacterial properties. The DCM and ethyl acetate extracts demonstrated high polyphenol content and effective biofilm inhibition. Further studies are warranted to isolate bioactive compounds and elucidate their mechanisms of action. Full article

Increasing cases of sunburn is one of the serious problems across the globe. In this connection, there is an urgent requirement for some effective sun screening agents. In the search for the same, nanoemulsions of some new synthesized and characterized chalcone derivatives were prepared and evaluated in vitro and in vivo. In order to meet the said objective, in the first step, vanillin was reacted with 4-aminoacetophenone in the presence of 15% sodium hydroxide and ethanol to synthesize the target compounds (C-1 to C-5). Progress of reaction was monitored using thin-layer chromatography (TLC). The crystals of purified compounds were characterized using spectroscopic techniques such as Infrared (IR) spectroscopy, ¹H-NMR spectroscopy, ¹³C-NMR, and mass spectrometry. We prepared the nanoemulsions of the final compounds (C-1 to C-5) and subsequently evaluated them for in vitro sun protection factor activity. The concentration of the nanoemulsions, consistently ranging from 0.88 to 0.91 mg/mL across all formulations, demonstrated a high degree of consistency. The range of particle size varied from approximately 172 to 183 nm, with low polydispersity index values (approximately 0.11 to 0.15). The negative zeta potentials recorded for all the formulations (ranging from −35.87 mV to −39.30 mV) showed that the nanoemulsions are electrostatically stable enough to keep them from sticking together. The pH values of the nanoemulsions ranged narrowly from approximately 5.00 to 5.16, which indicated the compatibility of emulsion with biological systems and the potential to reduce irritation or instability during administration. The viscosity of the nanoemulsions varied between 2.00 and 2.12 cP. In silico studies were performed using MMP-I and MMP-2 as target receptors. For in vitro SPF evaluation, the Mansur equation was employed. COLIPA guidelines were compiled for in vivo SPF evaluation. The nanoemulsions derived from compounds C-3 and C-4, designated as C-3NE and C-4NE, were more effective as anti-aging agents. Findings suggested the possible scope of further synthesis of newer synthetic derivatives of chalcones for furfur development nanoemulsions for better SPF activity. Full article

The durability of the materials is often limited as they fade under the influence of external factors, particularly light. The present research aimed to study the photodegradation of commercial inkjet inks in an aqueous solution. The results were compared with their stability on prints in order to establish the connection between the kinetics of photodegradation of dye in the solution and the durability of the final print. Thin-layer chromatography (TLC), chromatography with a mass selective detector (GC/MS), and spectrophotometric measurements were used to study the effect of light, including near UV. The results clearly show that the catalytic effect between different dyes cannot be avoided, as the inks for inkjet printing are usually a mixture of different colorants. A comparison of the results of photodegradation of the dye in solution and on the final prints does not show a direct connection due to the different influences of external factors. Consequently, it was established that it is not possible to predict the photodegradation of prints solely based on a single dye’s analysis in solution. The paper as a substrate must be included in the analysis, as it significantly influences the photodegradation of the print. Full article

This article primarily develops a new technology for the rapid large-scale screening of isoliquiritigenin-transforming strains based on the MTHM (microplate reader–TLC–HPLC–UPLC-MS) method. ISO is a chalcone compound with potential pharmacological activity, and its rich substitution sites on the benzene ring provide a solid foundation for structural modification and drug development. This study screened approximately 1500 strains and employed a microplate reader, thin-layer chromatography, high-performance liquid chromatography, and mass spectrometry to verify the transformation products, identifying 15 strains with significant transformation capabilities. This study demonstrates that the optimized MTHM method is efficient and reliable, capable of rapidly detecting subtle structural changes in flavonoids before and after microbial transformation. During the transformation process, bioactive flavonoid compounds, such as amentoflavone and 5′-methoxyflavonoid, were discovered. Additionally, the experiments revealed that Czapek medium, modified Martin medium, and LB medium exhibited high efficiency in screening transforming strains. This research provides new technical approaches for ISO structural optimization and drug development while highlighting the important application potential of microbial transformation in natural product development. Future studies could further explore the metabolic potential of these strains, optimize transformation conditions, and promote the application of ISO in the medical field. Full article

In recent years, the essential oil of Satureja species has been studied as a source of biocidal activity with potential applications in organic farming such as bio-pesticides. The present study aims to determine the potential of essential oil (EO), exudate fraction (EF) and methanolic extract (ME) of Satureja kitaibelii Wierzb. ex Heuff. to inhibit the mycelial growth of phytopathogenic fungi and acetylcholinesterase (AChE). Additionally, ME was tested for inhibitory activity on seed germination and root elongation. Phytochemical analysis was conducted using gas chromatography–mass spectrometry (GC–MS) and thin-layer chromatography (TLC). Biological activities were studied using in vitro methods. p-Cymene, limonene, geraniol, carvacrol and borneol were identified as the main components of EO. Oleanolic and ursolic acid, carvacrol and flavonoid aglycones were determined as the most abundant bioactive compounds of EF, whereas rosmarinic acid and flavonoid glycosides were found in ME. EO reduced the growth of all tested plant pathogens, indicated by 40% to 84% inhibition of mycelial growth (IMG). The growth rates of oomycetes Phytophthora cryptogea Pethybr. & Laff. and Phytophthora nicotianae Breda de Haan were affected to the greatest extent with 84% and 68% IMG. EF showed the most potent AChE inhibitory activity with IC₅₀ value of 0.18 mg/mL. Aqueous solutions of the ME with a concentration above 5 mg/mL were found to inhibit seed germination by more than 90%, whereas a reduction in root elongation was observed at 3 mg/mL. The present study provides for the first time data for the pesticidal properties of EO, EF and ME of S. kitaibelii. Full article

The chemical composition of asphalt binder is closely related to its macroscopic properties, and as an important road building material, its performance directly affects the service performance of asphalt binder pavement. Saturate, aromatic, resin, and asphaltene are the four most common chemical components of asphalt binders, collectively known as the SARA components. The SARA components are used to establish the corresponding relationship between the chemical composition and the macroscopic properties of asphalt binder, which is of great significance for further research on and development of high-performance asphalt pavement materials. This study used eight types of virgin asphalt binders as raw materials, labeled A–H. Firstly, the thin-layer chromatography–flame ionization detection (TLC-FID) method was used to test the SARA contents of the different asphalt binders. Then, the conventional, rheological, and low-temperature properties of the different binders were tested. Finally, gray relational analysis (GRA) and Pearson correlation analysis (PCA) were used to study the correlation between the asphalt binder’s SARA content and its macroscopic properties. The results indicate that the contents of asphaltenes and resins are crucial in determining the high-temperature performance of asphalt binder. By adjusting the ratio of these components, the high-temperature performance of asphalt binder can be optimized. An increase in the content of heavy components, particularly asphaltenes, negatively affects the low-temperature performance of asphalt binder. In contrast, a higher aromatic content enhances its low-temperature performance. Full article

In Cameroon, like in other African countries, infusions of Artemisia afra and Artemisia annua are widely used for the management of health-related problems, including malaria. The secondary metabolite contents of medicinal plants vary between different geographical regions and seasons, directly influencing their effectiveness in treating ailments. This study explores the phytochemical diversity and anti-plasmodial potential of A. annua and A. afra from distinct geographical locations within Cameroon, aiming to define the optimal chemical composition in terms of anti-plasmodial activity. Extracts were prepared from plants collected from diverse regions in Cameroon during both the rainy and dry seasons, and their metabolic contents were analyzed using Thin-Layer Chromatography (TLC), High Performance Liquid Chromatography (HPLC), and Gas Chromatography (GC). Their anti-plasmodial potential was assessed on a chloroquine-sensitive 3D7 Plasmodium falciparum strain. Additionally, the environmental parameters of the collecting sites were retrieved from multispectral satellite imagery. The activity profiles of the samples were associated with their environment, with distinct phytochemical compositions observed for each sample based on its geographical origin and season. Traces of artemisinin were detected in some of the A. afra samples, but it was present in the A. annua samples at a significantly higher concentration, especially in the rainy season samples (highest concentration in the Adamawa region, at 8.9% m/m artemisinin in the dry extract). Both plants are active at different levels, with A. annua more active due to the presence of artemisinin and A. afra probably active due to the presence of polyphenols. Both season and geographical location influence both plants’ metabolic contents and hence their antimalaria activity. These findings suggest that the selection of a suitable Artemisia sample for use as a potential antimalarial treatment should take into consideration its geographical origin and the period of collection. Full article

Tea tree oil (TTO), acquired from Melaleuca alternifolia (Maiden & Betche) Cheel, Myrtaceae, is a widely utilized essential oil (EO) due to its bioactive properties. The identification and quantification of TTO ingredients is generally performed by GC-MS, which provides the most accurate results. However, in some instances, the cost and time of analysis may pose a challenge. Thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC) offer a simpler, faster, cost-effective alternative capable of simultaneously analyzing and quantifying multiple samples. In addition, for more complex oils, two-dimensional (2D) or multigradient development (MGD) TLC provide better separation. Nevertheless, further development is sometimes necessary for the isolation of comigrating components. This study showcases a combined 2D-MGD TLC/HPTLC method for the successful separation of TTO components of interest. While human error, limited separation, and the partial evaporation of volatile components may still present a challenge during the process, considerable recovery of mono- and sesquiterpenes was achieved. This protocol also resulted in the successful isolation of target oxygenated monoterpenes (OMs) producing highly pure terpinen-4-ol (100%) and α-terpineol (≥94%), confirmed by GC-MS. The accurate enantiomeric distribution of these major OMs was verified by GC-FID through the use of a chiral cyclodextrin-based stationary phase. The observed positive enantiomer range (area percent) as well as (+)/(−) ratio for each terpinen-4-ol and α-terpineol were within acceptable ISO criteria. Full article

This study investigates the effects of chemical fractions on the mechanical properties of asphalt binders and predicts the mechanical properties of asphalt binders based on the chemical fractions. Initially, four fractions—saturate, aromatic, resin, and asphaltene (SARA)—were isolated from 36 asphalt binders using a thin-layer chromatography with flame ionization detection (TLC-FID) analyzer. Subsequently, the complex modulus and phase angle of the asphalt binders were determined for a range of frequencies and temperatures. The relationships between SARA content, heavy components, colloidal instability index, and the complex modulus and phase angle were analyzed. Advanced models, including quadratic polynomial and non-linear support vector machine (SVM) with sigmoid and RBF (Gaussian) kernels, were employed to predict the complex modulus and phase angle of asphalt binders based on the SARA data, and the reliability of these prediction models was critically assessed. The findings indicate that the contents of asphaltenes, resins, aromatics, and saturates significantly influence the rheological properties at different frequencies, though a clear correlation between SARA contents and both the complex modulus and phase angle was not established. Alternative methods should be considered for studying the mechanical properties of asphalt derived from SARA. The RBF kernel demonstrated superior performance compared to the quadratic polynomial and non-linear SVM with the Sigmoid kernel. While the non-linear SVM with the RBF kernel accurately predicts the complex modulus, it fails to predict the phase angle at low frequencies. The validation of this model confirmed its efficacy in capturing the relationship between input (SARA) and output (complex modulus and phase angle) vectors for each asphalt binder. The predicted complex modulus master curves closely match the experimental results, yet the model only approximates the trend of phase angle variation with frequency. Full article

The oleoresin and volatile fraction produced by conifers, such as Pinus pinaster, play a crucial role in plant defence, acting as precursors to resin acids and adapting in response to environmental stress or pathogen attacks. Abietadiene (abieta-7,13-diene), the biosynthetic precursor to abietic acid, has been identified as the most abundant compound in extracts from pinewood nematode (PWN)-infected P. pinaster trees. As abietadiene is not commercially available, this study aimed to achieve, for the first time, its isolation, structure elucidation, and detailed characterization from readily available forestry residues. Abietadiene was successfully isolated using thin-layer chromatography (TLC), and its purity and identity were evaluated using multiple analytical techniques: gas chromatography (GC), liquid chromatography (LC), nuclear magnetic resonance (NMR), and Fourier-transform infrared spectroscopy (FTIR). GC analysis indicated a purity of over 70% for the isolated compound, while LC provided the higher purity value of 98%. The identity of abietadiene was unequivocally confirmed through LC, FTIR, and NMR analysis. This work represents the first isolation and comprehensive characterization of abietadiene from a natural source, making detailed chemical data on this compound available to the scientific community. These findings may be used for future studies on the biological interactions and ecological roles of abietadiene, particularly in the context of plant defence and pathogen resistance. Full article

(1) Background: Targeted alpha therapy is an emerging field in nuclear medicine driven by two advantages: overcoming resistance in cancer-suffering patients to beta therapies and the practical application of lower activities of ²¹²Pb- and ²²⁵Ac-labelled peptides to achieve the same doses compared to beta therapy due to the highly cytotoxic nature of alpha particles. However, quality control of the ²¹²Pb/²²⁵Ac-radiopharmaceuticals remains a challenge due to the low activity levels used for therapy (100 kBq/kg) and the formation of several free daughter nuclides immediately after the formulation of patient doses; (2) Methods: The routine alpha detection on thin-layer chromatograms (TLC) of ²¹²Pb- and ²²⁵Ac-labelled peptides using a MiniScanPRO+ scanner combined with an alpha detector head was compared with detection using an AR-2000 scanner equipped with an open proportional counter tube. Measurement time, resolution and validity were compared for both scanners; (3) Results: For ²²⁵Ac, the quality control values of the radiochemical purity (RCP) were within the acceptance criteria 2 h after TLC development, regardless of when the TLC probe was taken. That is, if the TLC probe was taken 24 h after radiosynthesis, the true value of the RCP was not measured until 5 h after TLC development. For ²¹²Pb-labelled peptides, the probe sampling did not have a high impact on the value of the RCP for the MiniScanPRO+ and AR-2000. A difference was observed when measuring TLC with the AR-2000 in different modes; (4) Conclusions: The MiniScanPRO+ is fast, does not require additional equipment and can also measure the gamma spectrum, which may be important for some radiopharmaceutical production sites and regulatory authorities. The AR-2000 has a better signal-to-noise ratio, and this eliminates the need for additional waiting time after TLC development. Full article

Marine bacteria are crucial sources of alginate lyases, which play an essential role in alginate oligosaccharide (AOS) production. This study reports the biochemical characteristics of a new species of the Microbulbifer genus, Microbulbifer sp. HZ11. The strain HZ11 is Gram-negative, aerobic, flagellate-free, and rod-shaped. The genome of strain HZ11 is a 4,248,867 bp circular chromosome with an average GC content of 56.68%. HZ11 can degrade alginate and other polysaccharides. The carbohydrate-active enzyme (CAZyme) genes account for 4.57% of the total protein-coding genes of HZ11. Its alginate metabolism process is consistent with the characteristics of the polysaccharide utilization locus (PUL) system. The alginate lyase produced by strain HZ11 showed the highest activity at 50 °C, pH 8.5, and 0.1 M NaCl. The substrate preference was as follows: sodium alginate > poly mannuronic acid > poly guluronic acid. The thin layer chromatography (TLC) results revealed that the main enzymatic degradation products were monosaccharides or AOSs with a degree of polymerization (DP) of 2–3. These results help clarify the metabolism and utilization mechanism of alginate by marine bacteria and provide a theoretical reference for its application in the degradation of alginate and other polysaccharides. Full article

Background: Inflammation is a natural body’s defense mechanism against harmful stimuli such as pathogens, chemicals, or irradiation. But when the inflammatory response becomes permanent, it can lead to serious health problems. In the present study, the antioxidant and anti-inflammatory potentials of the Eriosema montanum methanolic extract (EMME), as well as its isolated fractions (FA-FJ) and compounds (1–7), were evaluated by using in vitro and cellular models. Methods: The total phenolic and flavonoid contents were determined using, respectively, Folin–Ciocalteu and aluminum chloride colorimetric methods, while 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 2,2′-diphenyl-1-picrylhy-drazyl (DPPH), and ferric ion reducing antioxidant power (FRAP) were used to determine the antioxidant activity. Thin Layer Chromatography (TLC) and column chromatography (CC) were used to isolate and purify the compounds and their elucidation using their NMR spectroscopic data. Results: EMME had moderate antioxidant and anti-inflammatory activities, while fraction FF showed much higher efficacy with IC₅₀ values of 34.64, 30.60, 16.43, and 77.29 μg/mL against DPPH, ABTS, NO, and 15-LOX inhibitory activities, respectively. The EMME fraction was found to be very rich in flavonoids and phenolic compounds, with 82.11 mgQE/g and 86.77 mgGAE/g of dry extract, respectively. Its LC-MS profiling allowed us to identify genistin (5) as the most concentrated constituent in this plant species, which was further isolated together with six other known compounds, namely, n-hexadecane (1), heptacosanoic acid (2), tricosan-1-ol (3), lupinalbin A (4), d-pinitol (6), and stigmasterol glucoside (7). Given these compounds, genistin (5) showed moderate activity against reactive oxygen species (ROS) and NO production in LPS-stimulated RAW264.7 cells compared to EMME, which suggested a synergy of (5) with other compounds. To the best of our knowledge, compounds (1), (2), and (3) were isolated for the first time from this plant species. Full article

Flash column chromatographic fractionation of tree of heaven (Ailanthus altissima) stem and trunk bark extracts, guided by thin-layer chromatography (TLC)–Bacillus subtilis assay and TLC–heated electrospray high-resolution tandem mass spectrometry (HESI-HRMS/MS), lead to the isolation of six known compounds: (9Z,11E)-13-hydroxy-9,11-octadecadienoic acid (13-HODE, A1), (10E,12Z)-9-hydroxy-10,12-octadecadienoic acid (9-HODE, A2), hexadecanedioic acid (thapsic acid, A3), 16-hydroxyhexadecanoic acid (juniperic acid, A4), 16-feruloyloxypalmitic acid (alpinagalanate, A5), and canthin-6-one (A6). Their structures were elucidated by HESI-HRMS/MS and one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy. This is the first study identifying A1–A5 in A. altissima tree. Except for A5, all isolated compounds exhibited antibacterial activity against B. subtilis in microdilution assays. A6 showed the strongest effect with a minimum inhibitory concentration (MIC) value of 8.3 µg/mL. The antibacterial activity of A3 and A4 is newly described. Full article