Thai Science and Technology Journal

Influence of NaCl on Growth of Nymphaea ‘Wanwisa’ in in vitro Culture

Krittinnakan Thongma — 2025-12-25

The effect of sodium chloride on the growth of Nymphaea ‘Wanwisa’ under sterile conditions for the selection of salt-tolerant lines was studied. Shoot fragments of Nymphaea ‘Wanwisa’ were cultured in MS liquid medium supplemented with 0.1 mg/L TDZ, 4 mg/L NAA, and sodium chloride at concentrations of 0, 25, 50, 75, and 100 mM. The experiment was arranged in a completely randomized design with 5 treatments and 8 replications each, and the cultures were maintained under sterile conditions for 4 months. The results showed that shoots of Nymphaea ‘Wanwisa’ grew well in the media supplemented with 25 and 50 mM sodium chloride, with no significant differences compared to the control medium without sodium chloride. Shoot growth was significantly reduced (P<0.05) when cultured in media containing 75 and 100 mM sodium chloride. These findings indicate that the shoots can grow normally in media supplemented with up to 50 mM sodium chloride, suggesting a tendency toward salt tolerance. Therefore, the results from this experiment provide a guideline for future development and production of salt-tolerant Nymphaea ‘Wanwisa’ under sterile conditions.

Effects of Water Soaking and Heating Duration on Seed Quality of Oil Palm (Elaeis quineensis Jacq.)

Tachawee Kwankaew — 2025-12-25

Breaking the dormancy of oil palm seeds by heat treatment relies on controlling seed moisture content and maintaining ambient temperature at an optimum level. A study on the effects of water soaking and heating duration on the seed quality of oil palm was conducted using a 3 x 4 factorial experiment in a completely randomized design (CRD). Two factors were tested, i.e., factor A-water soaking duration at three levels (3, 5, and 7 days), and factor B-heating duration at 39±1 ^๐C at four levels (30, 40, 50, and 60 days). The results showed that water soaking for 7 days followed by heating for 60 days produced the highest seed quality, with the highest germination percentage (66.00 %) and maximum premium germinated seed (57.75 %). Seed germinated the fastest under this treatment, with the lowest mean germination time of 14.98 days, a high germination speed index of 4.51, and the greatest shoot length of premium germinated seed at 11.23 mm. Therefore, soaking seeds for 7 days and heating at 39±1 ^๐C for 60 days is an effective alternative method for breaking dormancy of oil palm seeds through heat treatment.

Effects of Hibiscus Sabdariffa, Punica Granatum and Garcinia Mangostana Extracts on Lasiodiplodia Theobromae, the Causal Agent of Banana Stems End Rot Disease

Siriwan Samithiarporn — 2025-12-25

The study aimed to investigate the efficacy of rosella calyces, pomegranate peel, and mangosteen peel in controlling Lasiodiplodia theobromae (Lt-AYBa), the causal agent of stem end rot. The results indicated that extracts from rosella calyces, pomegranate peel, and mangosteen peel inhibit hyphal growth by 100 percent at minimum concentrations of 4,000, 7,000, and 3,000 ppm, respectively. In evaluations of disease control on Gros Michel bananas, it was found that in both Experiment Set 1 (Pre-Inoculation) and Experiment Set 2 (Post-Inoculation), treatments with rosella calyces, mangosteen peel, and pomegranate peel resulted in a lower average disease incidence area compared to the control group, whereas the chemical treatment showed the highest average disease occurrence area. Furthermore, a statistically significant difference was observed between the non-inoculated control group and the chemical treatment in both experimental conditions. The use of fungicides significantly increased the severity of crown rot disease in bananas, as they caused damage to the fruit tissue. In contrast, all three plant-based extracts effectively controlled the disease, demonstrating greater efficacy in prevention than in eradication.

Total Phenolic Content, Antioxidant and Antibacterial Activities of Lime, Tangerine and Kaffir Lime Peel Extracts

Chanisara Rudeekulthamrong — 2025-12-25

This research aimed to compare the total phenolic content (TPC), antioxidant activity, and antibacterial activity of crude extracts from the peels of three citrus fruits: lime, tangerine, and kaffir lime. Extraction was performed through maceration using three different solvents, distilled water, ethanol, and methanol, in a 1:10 solute-to solvent ratio at 50°C for 24 hours. Among the solvents tested, methanol proved to be the most effective for extracting phenolic compounds, followed by ethanol and then distilled water. The highest TPC was observed in the methanol extract of kaffir lime peel (11.76±0.15 milligrams of gallic acid equivalents per gram of dry weight), followed by the methanol extracts of tangerine and lime peels. Antioxidant activity, assessed via the DPPH radical scavenging assay, was highest in the methanol extracts for all citrus types and showed a positive correlation with TPC. For antibacterial activity, methanol extracts from lime, tangerine, and kaffir lime peels were tested using the agar disc diffusion method, producing inhibition zones of 12, 14, and 23 millimeters, respectively, against Escherichia coli, and 10, 12, and 24 millimeters, respectively, against Staphylococcus aureus. Further analysis of MIC and MBC values indicated that the methanol extract from kaffir lime peel exhibited superior antibacterial and bactericidal effects compared to the other citrus extracts. It also showed greater efficacy against S. aureus (a gram positive bacterium) than E. coli (a gram-negative bacterium). HPLC analysis identified hesperidin as the main phenolic compound in the extracts.

Cultivation of Tao Macroalgae (Spirogyra sp.) in Greenhouse With pH Control System

Waratit Donsujit — 2025-12-25

Cultivation of Tao macroalgae (Spirogyra sp.) was conducted in a greenhouse using raceway ponds equipped with a pH control system. The algae were initially grown at 500 g per pond (fresh weight) in 1,000 L of culture water for a period of 10 days. Growth and biomass production under different pH control conditions were compared. Three pH control treatments were tested: no pH control (control),pH maintained between 7.0-7.5, and pH maintained between 7.5–8.0. After 10 days of cultivation, the pH range of 7.5–8.0 resulted in the highest growth performance, with an average daily weight gain of 246.3 g/day (fresh weight), a specific growth rate of 17.8%/day, and a biomass yield of 148.1 g/m²/day. These values were significantly higher than those of the other treatments (p<0.05). The results indicate that pH control is an important factor influencing algal growth and biomass production. Therefore, the cultivation of Tao macroalgae in this greenhouse system shows strong potential for further application and development towards commercial production.

Genetic Relationships Assessment and Identification of Nepenthes and Their Hybrids Using SCoT Technique

Ganin Trangtrachoo — 2025-12-25

The pitcher plant (Nepenthes) is a carnivorous species with high ornamental value due to the aesthetic appeal of its pitchers. This makes it a popular choice for decorative purposes and plant collections. However, identifying Nepenthes based solely on morphological characteristics can be challenging because many hybrids closely resemble one another. This study employed the Start Codon Targeted (SCoT) marker technique to differentiate 15 Nepenthes varieties, including eight species and seven hybrids. Of the 80 SCoT primers tested, 19 produced clear and highly polymorphic amplification profiles. Polymorphic primers were selected based on band clarity and the degree of polymorphism observed. Genetic relationships were analyzed using the Unweighted Pair Group Method with Arithmetic Mean (UPGMA), revealing similarity coefficients ranging from 0.47 to 0.86. The samples were grouped into six distinct clusters.

Development of a Ailkworm-Rearing House Using the Internet of Things (IoT) System for Temperature and Humidity Control

Supattra Sathianteerapap — 2025-12-25

This research involves the development of a silkworm-rearing house equipped with an Internet of Things (IoT) system to regulate temperature and humidity within the facility. It also includes the design of the rearing area and processes in accordance with the standards outlined in TAS 8203 by the National Bureau of Agricultural Commodity and Food Standards (2017). The silkworm-rearing facility is located in Dan Thap Tako Subdistrict, Chom Bueng District, Ratchaburi Province. The Tubtim Siam 06 variety of silkworms was used as the model species. The results indicate that the IoT-equipped silkworm-rearing house, used for rearing silkworms from the 1^st instar to the 5^th instar, maintained temperature between 25.72°C and 30.25°C, and relative humidity values between 77.66%RH and 89.90%RH during the periods of 6:00 a.m.-12:00 p.m. and 6:00 p.m.-12:00 a.m. The IoT system effectively regulated both temperature and humidity, providing an environment suitable for silkworm development. The cocoon products produced in this facility demonstrated superior quality compared with reference data from the Queen Sirikit Department of Sericulture. Moreover, the silk cocoons obtained were clean, safe, and suitable for medical applications. Therefore, this silkworm-rearing house equipped with the IoT system is considered suitable and convenient for farmers, enabling year-round silkworm production.

Changes in Clostridium Difficile Toxin A/B Detection Results Using Lateral Flow Immunochromatography

Kridsada Sirisabhabhorn — 2025-12-25

Toxin types A (TcdA) and B (TcdB) of Clostridium or Clostridiodes difficile (C. difficile) are responsible for causing severe diarrhea in patients with CDI (Clostridioides difficile infection), and can lead to fatal outcomes. Detection of glutamate dehydrogenase (GDH) and TcdA/B using lateral flow immunochromatography (IC) is crucial for CDI diagnosis. However, when immediate testing is not possible, fecal samples are typically stored at 4°C until official analysis, sometimes for up to 5 days. This study aimed to determine the critical day—the first day on which IC test results for GDH and TcdA/B begin to deviate from Day ₁ results, potentially affecting clinical decision-making. A total of 61 post-analysis fecal samples from patients at Thammasat University Hospital, Pathumtani, Thailand, were divided into five aliquots per sample, stored at 4°C, and tested for GDH and TcdA/B using the IC method from Day 1 to Day 5. The agreement of test results across the 5 days was evaluated using Cohen’s Kappa coefficient. The results identified Day 2 as the critical day. Overall, IC test result patterns between Day ₁ and Days _2–5 showed high agreement (almost perfect concordance). However, beginning on Day ₂, a 4.90–6.60% increase in negative results was observed, which may lead to missed diagnoses and delayed treatment. In conclusion, GDH and TcdA/B detection using the IC method should be performed as soon as possible to reduce the lethal rate.