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
คณะสถาปัตยกรรม ศิลปะและการออกแบบ
This research focuses on the design of a Metaverse Prototype Thai Film Archive (Public Organization) to study immersive experiences. The aims were to: 1) examine design concepts and technologies for digital immersion, 2) create and showcase these designs in the Metaverse cinema, and 3) evaluate the results and formulate knowledge for virtual exhibition design using qualitative research methods, including prototype testing with participant interviews to assess satisfaction. The design principles consisted of architectural, exhibition, and user experience concepts, leading to a virtual world creation process involving 3D structural modeling, interactive functionalities, and exhibition layout before prototype testing. The evaluation included tests by ten participants and group discussions on overall experience, cinema content value, Metaverse design, and educational enhancement in museums. The design evaluation indicated a 70% positive overall experience, with half of the users finding stable usability. However, significant viewing barriers were identified, with a high need for operational instructions and navigational aids. Content understanding and Metaverse interaction were perceived positively, and the educational aspect was highly valued. The study concludes that while the overall experience was good, technology limitations (as of 2023) and interaction challenges require ongoing refinement to improve stability and usability, although the educational value was affirmed as strong.
คณะวิศวกรรมศาสตร์
The evaluation of mango yield and consumer behavior reflects an increasing awareness of product origins, with a growing demand for traceability to understand how the produce has been cultivated and managed. This study explores the relationship between mango characteristics and cultivation practices before harvest, using location identification to provide insights into these processes. To achieve this, a model was developed to detect and locate mangoes using 2D images via a Deep Learning approach. The study also investigates techniques to determine the real-world coordinates of mangoes from 2D images. The YOLOv8 model was employed for object detection, integrated with camera calibration and triangulation techniques to estimate the 3D positions of detected mangoes. Experiments involved 125 trials with randomized mango positions and camera placements at varying yaw and pitch angles. Parameters extracted from sequential images were compared to derive the actual 3D positions of the mangoes. The YOLOv8 model demonstrated high performance with prediction metrics of Precision (0.928), Recall (0.901), mAP50 (0.965), mAP50-95 (0.785), and F1-Score (0.914). These results indicate sufficient accuracy for predicting mango positions, with an average positional error of approximately 38 centimeters.
คณะอุตสาหกรรมอาหาร
Most rice is consumed as cooked, milled rice, but a small portion is also ground into flour or separated into a starch fraction and used by the food industry as a gluten-free ingredient. This study aims to find out if different types of rice flour and starch, such as white and colored rice, could be used in industry. This study employs green modification techniques to slow down the digestion process by combining polyphenols with starch. Our initial study found that the raw colored rice has a lower glycemic index than other types of rice, such as brown or white rice. Another study that looked at how the quality of colored rice flour was changed by different methods also discovered that out of the six green methods (annealing, heat moisture treatment, ultrasound, pregelatinization, wet-microwave, and dry-microwave). It found that ultrasound improved the polyphenol bioaccessibility in the rice flour and reduced the digestion rate. The pregelatinization process led to the flour having high solubility and an estimated glycemic index. Different techniques affected the flour/starch quality in different ways. Therefore, for further industrial application, it could also be easier to select the method for food product based on their required techno-functional quality of flour/starch. In addition to the modification techniques, this study showed that the high bioaccessible polyphenol content and high polyphenol content in rice greatly slowed down the rate of digestion. This study also open for further exploring the possibility of using high polyphenol agricultural waste to modify starch and flour in a sustainable manner.