Listeriosis is a severe foodborne illness characterized by a fatality rate exceeding 30%, attributed to the pathogen Listeria monocytogenes. This study evaluated 160 lactic acid bacteria (LAB) isolated from Thai pickled crabs for their potential as agents against L. monocytogenes and for their probiotic properties and probiogenomic characteristics. Among these strains, strain DRC3-2 exhibited activity through the synthesis of bacteriocin DRC3-2, which significantly inhibited L. monocytogenes ATCC 19115 in spot-on-lawn assays. Phenotypic and whole-genome analyses revealed that strain DRC3-2 thrived in environments with 2-6% NaCl, pH values ranging from 3 to 9, and temperatures between 25 and 45°C. Based on average nucleotide identity (ANI) and digital DNA‒DNA hybridization (dDDH) values, strain DRC3-2 was taxonomically classified as Lactococcus lactis subsp. hordinae. The production of bacteriocin DRC3-2 peaked during the late stationary phase, following its synthesis in the early exponential growth phase. BAGEL4 analysis identified the putative novel bacteriocin DRC3-2 as lactococcin A and B, with respective bit-scores of 40.05 and 36.58. In silico safety assessments confirmed the nonpathogenic nature of strain DRC3-2 in humans, highlighting its absence of antibiotic resistance genes. Finally, this investigation underscores the novel bacteriocin DRC3-2 for application in the prevention and treatment of L. monocytogenes infections.
Listeria monocytogenes เป็นเชื้อก่อโรคที่มักพบในอาหารที่มีการปนเปื้อน สามารถอยู่รอดในสภาวะที่รุนแรง เช่น อุณหภูมิต่ำ ความเป็นกรดสูง ความเข้มข้นของเกลือสูง ซึ่งทำให้มีความเสี่ยงอย่างมากในระบบย่อยอาหารของมนุษย์ ดังนั้นจึงศึกษาแบคทีเรียกรดแลคติกที่มีความสำคัญในอุตสาหกรรมอาหารและยาเนื่องจากมีคุณสมบัติเป็นโพรไบโอติก และแบคทีเรียกรดแลคติกบางชนิดที่สามารถผลิตแบคเทอริโอซินหรือเปปไทด์ต้านจุลชีพที่มีฤทธิ์ทางชีวภาพ และแบคเทอริโอซินที่มีประสิทธิภาพในการยับยั้งแบคทีเรียก่อโรค ซึ่งถือว่าเป็นทางเลือกที่น่าสนใจแทนการใช้ยาปฎิชีวนะแบบดั้งเดิม เนื่องจากช่วยลดการพัฒนาการดื้อยาของแบคทีเรีย นอกจากนี้แบคเทอริโอซินยังมีความเสถียรสูง สามารถทนต่ออุณหภูมิที่รุนแรงและสภาวะเป็นกรดได้ อีกทั้งยังไม่เป็นพิษต่อเซลล์มนุษย์ การศึกษานี้จึงมุ่งหมายเพื่อศึกษาแบคเทอริโอซินชนิดใหม่จาก Lactococcus lactis subsp. hordinae DCR3-2 ซึ่งแยกได้จากปูดอง เพื่อประเมินฤทธิ์การต้านจุลชีพของแบคทีเรียชนิดนี้ และการวิเคราะห์ทางbioinformatics เพื่อยืนยันว่าสายพันธุ์ DCR3-2 มีความปลอดภัยสำหรับมนุษย์และมีคุณสมบัติโพรไบโอติก
คณะเทคโนโลยีการเกษตร
Efficient durian orchard development requires integrating knowledge, technology, and innovation from farmers and academics to cope with environmental changes and market demands. The Durian Web-based Learning Hub is an online learning platform developed to serve as a central hub for knowledge transfer from experts and as a space for experience exchange among farmers. Users can access learning resources conveniently and continuously. This platform is part of the Innovation Project for Production and Marketing Information Management Innovation for Enhancing the Quality of Durian Production Entering into Premium Markets, supported by the Program Management Unit for Area-Based Development (PMUA)
คณะเทคโนโลยีการเกษตร
Rice is a salt-sensitive crop. The objective of this study was to evaluate the effect of salinity at flowering stage on physiological traits and yield of landrace rice. The experiment design was 4*10 Factorial in RCBD with 4 replications. Factor A was four salinity levels: control, 6, 12 and 16 dS/m; Factor B was 10 rice varieties. Data were collected on physiological traits and grain yield. The results showed that increasing salinity level decreased rice yield. The highest yield reduction was found when the rice received salt stress at 16 dS/m. In addition, rice varieties showed different yield performance when exposed to salt stress. In this found that Hom Yai variety had the lowest yield reduction when grown at 16 dS/m salinity level and did not differ from salt tolerant check variety.
คณะครุศาสตร์อุตสาหกรรมและเทคโนโลยี
This aimed to 1) develop an effective augmented reality (AR) media integrated with the metaverse to enhance English phonics and communication skills. 2) To evaluate English pronunciation skills using augmented reality media integrated with the metaverse, and 3) To assess English communication skills through interactions within the metaverse. The sample group comprised 120 Grade 4 students from two classrooms in the first semester of the 2024 academic year, selected through cluster random sampling and divided into experimental and control groups. The research instruments included AR media sets, media quality assessment forms, phonics tests, and English communication skills assessment forms, administered before and after the learning intervention. Data analysis employed mean (x ̅), standard deviation (S), t-tests for independent samples, and one-way analysis of variance (Multivariate Analysis of Variance: One-Way MANOVA) to compare mean score differences between the experimental and control groups. Results indicated that the overall quality of the AR media kit with the metaverse was rated at a very high level (x ̅= 4.80, S.D. = 0.12). Evaluating specific aspects showed that the content quality was at the highest level (x ̅= 4.92, S.D. = 0.07), while the media production technique also rated highly (x ̅ = 4.70, S.D. = 0.17). Furthermore, the English pronunciation and communication skills of the Grade 4 students using the AR media with the metaverse were significantly higher after the intervention compared to before, the overall quality of the AR media integrated with the metaverse was rated at the highest level (x ̅= 4.80, S.D. = 0.12). For individual aspects, content quality was rated at the highest level (x ̅= 4.92, S.D. = 0.07), and media production techniques were also rated at the highest level (x ̅ = 4.70, S.D. = 0.17). Comparing the mean scores of English pronunciation and communication skills between the two groups, it was found that the experimental group using AR media integrated with the metaverse demonstrated significantly higher English pronunciation skills than the control group (F(1, 89) = 3261.422, p = 0.001, Partial η² = 0.98). Additionally, the experimental group exhibited significantly higher English communication skills than the control group (F(1, 89) = 4239.365, p = 0.001, Partial η² = 0.98). These results aligned with the research hypothesis that "Grade 4 students’ English pronunciation and communication skills post-learning with AR media integrated with the metaverse would significantly improve compared to their pre-learning levels at the .05 level of significance.