KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 10 of 17

Some of the metrics are blocked by your
consent settings
Williamson-Hall analysis of lattice strain in green-synthesized ZnO nanoparticles using Mitragyna speciosa extract: microstructural insights and antibacterial application
(2026-07-01)
Thongpool, Voranuch
;
Phunpueok, Akapong
;
Jaiyen, Sarawut
;
Limsuwan, Pichet
Green synthesis is a sustainable method for producing ZnO NPs. However, detailed microstructural interpretation remains limited. In this study, ZnO NPs were synthesized using Mitragyna speciosa leaf extract and systematically analyzed with emphasis on lattice characteristics. Structural and morphological analysis using UV–vis, FTIR, FESEM-EDS, and XRD techniques confirmed the formation of highly crystalline ZnO with a hexagonal wurtzite structure. Williamson-Hall (W-H) analysis was applied using three deformation models: UDM, USDM, and UDEDM to separate crystallite size and lattice strain components of the crystal structure. The results revealed relatively large crystallite sizes (∼39–43 nm) with low microstrain (2.09–2.30 × 10⁻3) and low deformation energy density (3.1 × 10⁻4 J m⁻3), suggesting comparatively low lattice strain characteristics. The optical band gap obtained from the Tauc plot analysis is approximately 3.03 eV, consistent with the properties of the ZnO semiconductor. Antibacterial activity was evaluated as a preliminary functional assessment, showing typical Gram-dependent behavior. This work highlights the applicability of W–H analysis for detailed microstructural evaluation in green-synthesized ZnO NPs.
Some of the metrics are blocked by your
consent settings
Bioactive Potential of Gardenia obtusifolia Extracts: Antibacterial Effects of the Ethyl Acetate Fraction against Clinical Pathogens
(2026-03-01)
Natsakulmongkon, Phetrung
;
Poeaim, Supattra
Gardenia obtusifolia, a traditional medicinal plant from Southeast Asia, was investigated for its phytochemical composition and bioactivity using methanol extracts and solvent-partitioned fractions from the leaves, fruit pulp, and rind. The plant material was authenticated morphologically and confirmed through matK gene analysis. Phytochemical screening revealed the presence of phenolic compounds, flavonoids, tannins, coumarins, and alkaloids. Among the fractions tested, the rind ethyl acetate fraction exhibited strong antibacterial activity against clinical pathogens, high phenolic content, and potent antioxidant capacity. GC-MS profiling identified key bioactive compounds, including vanillic acid, octadecane, and 5-hydroxymethylfurfural, which likely contribute to the observed bioactivities. Among the solvent fractions, the rind ethyl acetate fraction demonstrated strong anti-tyrosinase activity. This fraction consistently exhibited high phenolic content and potent antioxidant capacity, suggesting that these bioactivities are attributable to key phytochemicals known for antioxidant effects. Purification and GC-MS profiling identified bioactive compounds in the rind ethyl acetate fraction, revealing vanillic acid as a major contributor to antioxidant activity. G. obtusifolia shows great promise for application in the cosmetic industry as a natural ingredient for skin-whitening and anti-aging formulations. However, further in vivo and clinical studies are required, as in vitro results may not directly reflect clinical efficacy.
Some of the metrics are blocked by your
consent settings
Antibacterial effects of bioactive restorative dental materials on Streptococcus mutans: An in vitro study using the direct contact test
(2025-10-01)
Boondireke, Sirirat
;
Kitrueangphatchara, Onsasi
;
Sukajintanakarn, Charnsak
;
Chiaraputt, Sirichan
This in vitro study aimed to evaluate the antibacterial activity of various restorative dental materials against Streptococcus mutans, a major cariogenic pathogen. The materials tested included a resin composite (Estelite Sigma Quick), conventional glass ionomer cement (Fuji IX), resin-modified glass ionomer cement (Fuji II LC), a bioactive resin-based material (Activa BioACTIVE Restorative), and a calcium silicate-based material (Biodentine). Antibacterial activity was assessed using the direct contact test (DCT). Each material was tested against S. mutans at 3, 6, 16, and 24-h intervals. Colony-forming units (CFU) were quantified following serial dilution and culture on BHI agar. Statistical comparisons were conducted using the Kruskal–Wallis test. All materials except Estelite demonstrated significant antibacterial effects. Biodentine exhibited the greatest inhibition (P ≤ 0.001), followed by Fuji IX (P ≤ 0.001), and Fuji II LC (P ≤ 0.01). Activa BioACTIVE showed significant bacterial reduction at 16 and 24 h (P ≤ 0.05). Estelite showed no significant antibacterial effect (P > 0.05). Biodentine displayed sustained and pronounced antibacterial effects, suggesting its suitability for patients at high risk of caries. Fuji IX and Fuji II LC also exhibited antibacterial properties, though to a lesser extent. The findings support the use of bioactive restorative materials in managing bacterial presence and enhancing restoration longevity. The superior antibacterial performance of Biodentine highlights its potential role in preventing secondary caries, particularly in high-risk populations. Clinicians are encouraged to consider bioactive materials as part of comprehensive caries management strategies.
Some of the metrics are blocked by your
consent settings
INVESTIGATION OF BIOACTIVITIES FROM CASSIA FISTULA LINN. EXTRACTS
(2025-01-01)
Sriwatcharakul, S.
This study explores the bioactivities of Cassia fistula Linn. (commonly known as the golden shower tree) by comparing the antioxidant, antibacterial, and cytotoxic properties of pod and seed ethanol extracts collected from Chonburi and Samut Prakan provinces in Thailand. The antioxidant potential was assessed through DPPH radical scavenging assay, where pod extracts exhibited higher activity than seed extracts, with IC₅₀ values of 0.98 and 1.09 mg/ml, respectively. The total phenolic content was highest in seed extracts from Samut Prakan (205.00 mg GAE/g extract), followed closely by pod extracts from Chonburi (167.50 mg GAE/g extract). Antibacterial screening via agar disc diffusion method showed that all extracts had significant inhibitory activity against gram positive; Bacillus subtilis and Micrococcus luteus. Samut Prakan pod extract inhibit M. luteus better than gentamicin. Cytotoxicity tests against MCF-7 breast carcinoma cells indicated that all extracts were non-toxic, and some even promoted cell viability, suggesting safety for potential therapeutic applications. These findings suggest that Cassia fistula, particularly its pod extracts, is a promising natural source candidate for future development in health-related applications.
Some of the metrics are blocked by your
consent settings
Comparative evaluation of leaf and seed methanolic extracts obtained from Sophora tomentosa Linn. for phytochemical, phenolic content, antioxidant and antibacterial activities
(2023-01-01)
Laowklang. Poeaim, P. S.
;
Tangthirasunun, N.
Sophora tomentosa Linn. (Fabaceae), also known as a yellow necklace pod, is a traditional medicinal plant widely used to treat dysentery and diarrhea. This study evaluated the biological activities of methanolic leaf and seed extracts of S. tomentosa. The total phenolic content of methanolic leave (STL) seed (STS) and dechlorophyll of leave extract (DSTL) showed 92.02 ±1.78, 38.48 ± 0.61, and 35.35 ± 2.45 mg GAE/g extract), respectively. For antioxidant activity, DPPH, ABTS and FRAP assay was found in leaves (STL) more than in dechlorophyll of leave extract (DSTL) and seed (STS). The methanolic extracts were assessed for antibacterial activity against eight pathogenic bacterial species. The seed extract showed the most potent antibacterial activity against Kocuria rhizophila with 12.85±3.85 mm inhibition zones. For phytochemical evaluation, both leaf and seed extracts exhibited alkaloids and coumarin. The results showed that the leaf extract (STL) had higher antioxidant activity and total phenolic content than seeds and dechlorophyll of leave extract (DSTL). On the other hand, the seed extract presented the most potent antibacterial activity. The current study suggested that both leave and seed extracts of S. tomentosa gave the potential source of natural bioactive compounds, which will be further evaluated in other biological activities.
Some of the metrics are blocked by your
consent settings
Highly transparent flexible CuI film for antibacterial applications
(2022-02-01)
Worananthakij, Worakrit
;
Manklinniam, Piyapan
;
Limsuwan, Pichet
;
Sakulkalavek, Aparporn
;
Sakdanuphab, Rachsak
In this study, the CuI film was firstly revealed to have significant antibacterial activity. The as-prepared CuI thin films on flexible plastic (polyvinylchloride, PVC) substrates were developed by the liquid iodination method. This method is simple, low-cost and environmentally friendly to fabricate flexible CuI films. A suitable reaction time between the Cu<inf>3</inf>N precursor and aqueous iodine solution is the key parameter for developing highly transparent CuI films, and an average transmittance in visible spectrum was higher than 85%. In addition, the CuI films have prominent antibacterial effects against Staphylococcus aureus and Escherichia coli. These properties indicate that CuI films are promising for built-in application to top layer displays in public places, such as hotel and department stores, ticket machines and touch screens in smart devices.
Some of the metrics are blocked by your
consent settings
Dip- and Spray-coating of Schanz pin with PLA and PLA nanosphere for prolonged antibacterial activity
(2021-10-01)
Chinavinijkul, Panarin
;
Riansuwan, Kongkhet
;
Kiratisin, Pattarachai
;
Srisang, Siriwan
;
Nasongkla, Norased
In this study, variation of coating parameters was performed to determine a suitable condition for a vancomycin-coated Schanz pins in poly(lactic acid) (PLA) for prolonged antibacterial activity. Herein, the solvent used to dissolve the polymer (DCM vs. CHCl<inf>3</inf>), the concentration of the polymer in the solvent (2 vs. 5% w/v), the vertical withdrawing speed of the implant from the solution (0.4 vs. 2.4 cm/s), and the number of dip-coating cycles denoted in layers (1 L vs. 3 L) were investigated for its drug loading. Results showed that the optimal parameters were at 2% w/v PLA in DCM at 0.4 cm/s withdrawing speed and at 3 cycles for a high vancomycin loading with low deviation in result. Another experiment was performed by varying the concentration (1, 2, 4% w/v) and number of dip-coating cycles (10 L, 20 L, 30 L) which finalized 2% w/v PLA at 10 cycles as the optimal drug loading at 2.04 ± 0.09 mg. When observing the drug-release profile, the prior formulation released 2.21 ± 0.01 mg or 92.88 ± 0.44% of drug in one week. To reduce the amount of drug release in the first week, the method was further improved by spray-coating with PLA nanospheres (PLA-NS) for multiple cycles (10-, 20-, and 30-NS) to prolong drug release. After one, two, and three weeks, the drug-release were around 76%, 80%, and 88%, respectively. However, more drugs were lost as the number of cycles increases which suggests that lower (10-NS) coating cycle is better. Therefore, the final process was selected to be 2% PLA dip-coated for 10 cycles then spray-coated with PLA nanosphere for 10 cycles. Results showed that this method can help prolong release for at least 24 days. A short-term bacterial and cytotoxicity tests were done for 3 days with no S.aureus formed nor cytotoxicity. These results supported that the coating was successful in inhibiting the growth of S.aureus.
Some of the metrics are blocked by your
consent settings
Abyssomicin derivatives from the rhizosphere soil actinomycete Microbispora rhizosphaerae sp. nov. TBRC6028
(2021-05-01)
Bunbamrung, Nantiya
;
Kittisrisopit, Suchada
;
Intaraudom, Chakapong
;
Dramae, Aibrohim
;
Thawai, Chitti
Three undescribed abyssomicin derivatives, including microbimisin, abyssomicins Z1, and Z2, were isolated from the soil actinomycete Microbispora rhizosphaerae sp. nov. TBRC6028. Chemical structures were determined by NMR spectroscopic data (1H, 13C, COSY, HSQC, HMBC, and NOESY spectra) and the absolute configurations were verified by single-crystal X-ray diffraction analyses together with the ECD spectral data. Microbimisin and abyssomicin Z1 exhibited weak antibacterial activity against Bacillus cereus with MIC values of 25.0 and 50.0 μg/mL without cytotoxicity against MCF-7 and Vero cells at the concentration of 50 μg/mL.
Some of the metrics are blocked by your
consent settings
Synthesis of ZnO nanoparticles by Ball-milling process for biological applications
(2021-01-01)
Wirunchit, S.
;
Gansa, P.
;
Koetniyom, W.
This research is focus on synthesis of ZnO nanoparticles (ZnO-NPs) for biological application by Ball-milling process. This research presents the synthesis of ZnO nanoparticles with the difference calcined temperatures ranging from 400 to 900 °C effect on size and morphology. The synthesis ZnO nanoparticles were characterized by employing technique including X-ray diffraction technique (XRD), Fourier Transform Infrared spectroscopy (FT-IR) and Raman spectroscopy. The morphology and size of ZnO nanoparticles determined by Field Emission Scanning Electron Microscope (FE-SEM) and finally studied the effect of antibacterial activity of ZnO NPs. It was found that the temperature at which high purity ZnO is = 800 °C. Especially, at 800 °C, the smallest particle size of ZnO nanoparticles was obtained. The morphology of ZnO nanoparticles from Ball-milling process is spherical. Bacteriological properties of ZnO nanoparticles were found that the synthesis by using the Ball-milling process was high effective to inhibit bacteria.
Some of the metrics are blocked by your
consent settings
Antibacterial, antitubercular, antimalarial and cytotoxic substances from the endophytic Streptomyces sp. TBRC7642
(2020-04-01)
Bunbamrung, Nantiya
;
Intaraudom, Chakapong
;
Dramae, Aibrohim
;
Thawai, Chitti
;
Tadtong, Sarin
Eight previously undescribed naturally-occurring compounds, including abyssomycins Y - Z, methyl aeruginoate, desferri-ferrithocin-4-hydroxyphenethylester, streptomethiocins A - B, furaquinocin I, and streptolactone, along with eleven known compounds were isolated from the endophytic Streptomyces sp. TBRC7642. The chemical structures were determined based on spectroscopic means including 1D, 2D NMR spectroscopy and mass spectrometry. The absolute configurations were assigned by relying on CD spectra and their optical rotations. In addition, the isolated compounds were evaluated for biological activity, such as antimalarial, antitubercular, antibacterial (both Gram-positive and Gram-negative bacteria), as well as for cytotoxicity against MCF-7, NCI–H187, and Vero cells.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results