Provinces Of Northern Thailand Research Articles

Diversity of Plant Colorant Species in a Biodiversity Hotspot in Northern Thailand

Growing concerns regarding health and eco-safety have led to a resurgence in the recognition of natural products. Although plant colorants are often mentioned in ethnobotanical studies in northern Thailand, they have not been comprehensively examined. This study aims to (i) investigate the colorant plants used by ethnic minorities in northern Thailand and (ii) compare colorant plants used among the groups in northern Thailand with other regions worldwide. Data on colorant plants used by ten ethnic groups across 142 villages in northern Thailand were extracted in a systematic review of 42 published references. The importance of the colorant plant species was evaluated using the ethnobotanical index “use value” (UV), and the homogeneity of knowledge was assessed using the “information consensus factor” (ICF). The similarity of colorant plants used among the ethnic minority groups and beyond was evaluated using Jaccard’s index. The 42 published references included information about 104 colorant plant species belonging to 85 genera and 43 families from seven provinces in northern Thailand. This represents nearly half of the 212 colorant plant species reported across all 72 provinces in Thailand. The most important species were Strobilanthes cusia and Morinda angustifolia, which are sources of blue and red colors. Fabaceae, Rubiaceae, and Lamiaceae were the plant families with most species used as colorants. The colorant plant species yielded ten different color shades, with blue being the most prevalent. The Jaccard’s index varied from 0 to 0.27 among the northern Thai ethnic minorities and from 0 to 0.13 for regions outside of northern Thailand. The regions located closest to northern Thailand exhibited the highest degree of similarity. This study provides valuable insights into the traditional knowledge and usage of dye plants in northern Thailand, contributing to preserving the cultural heritage and providing basic knowledge for the sustainable use of natural colorants for modern applications.

Perceptions of Learners and Specialists Toward ECHO Palliative Care Project in Thailand.

The Extension of Community Health Outcomes (ECHO) is a global movement that aims to decentralize the knowledge of specialists to primary care. A pilot, ECHO palliative care project in Thailand, was introduced to enhance the implementation of palliative care practice. To assess learners' and palliative care specialists' perceptions toward the ECHO palliative care project to improve and expand the project in the future. A total of 15 hospitals in 7 provinces in Northern Thailand, including provincial and district hospitals. A qualitative study was conducted among learners (primary care providers) and palliative care specialists who participated in the pilot program. Semi-structured interviews were used to explore the potential impact of the project on clinical practice, the strengths and weaknesses of the ECHO program and platform in the Thai context, and suggestions for expansion. Thematic analysis was used for qualitative analysis. Pre- and post-confidence scores, using a 5-point Likert Scale, for palliative care practice among learners were analyzed using paired T-tests. Twenty participants were interviewed: 15 learners and 5 palliative care specialists. The confidence in practicing palliative care after participating in the ECHO palliative care project significantly increased for the learners, from 2.93 (95% CI, 2.49-3.38) to 3.93 (95% CI, 3.68-4.19) points (P = .003). Three themes emerged through the process evaluation of the pilot ECHO palliative care project: (1) applicable lessons that can translate to practice, (2) an effective learning program and assessable platform, and (3) suggestions for expansion. The ECHO palliative care project increased confidence in providing palliative care for primary care providers in Thailand. Through capacity building, participants reported applying the knowledge to improve local health services and develop a network for consultations and referrals. There is potential for expansion of the ECHO palliative care project in Thailand.

Mites (Acari) infesting stored animal feed products in northern Thailand

Storage mites are serious pests of stored animal feeds and animals that consume mite-infested feed could reduce feed intake and eventually cause weight loss. To understand the mite species and infestation rates of them in animal feeds, we conducted a survey of mite infestations in samples of animal feeds from animal feed shops, feed mills, or chicken farms in eight provinces in northern Thailand. High mite infestation rates were observed in chicken feed (42.9%), followed by pig feed (26.7%). No mites were observed in fish and frog feeds. Mites were common in pelleted feeds (n = 96) or raw materials (n = 3), but was never observed in extruded feeds (n = 33). The mite species identified include three storage mites: Suidasia pontifica, Dermatophagoides farinae, and Aleuroglyphus chinensis, as well as the predatory mites Cheyletus malaccensis, Blattisocius keegani, and B. everti. Among them, A. chinensis and B. everti, are newly recorded in Thailand. Suidasia pontifica was dominant in chicken and pig feeds, and could be the major storage mite pest in northern Thailand. Figures and identification keys are provided.

Strategy Design of PM2.5 Controlling for Northern Thailand

The emission of fine particulate matter (PM2.5) in dry season from the open biomass burning has caused a long-term negative impact on residents’ health in Northern Thailand. This study takes Chiang Mai and Chiang Rai provinces in Northern Thailand as the study areas to identify pollution episodes, analyze PM2.5 source trajectories, and finally propose pollution control strategies accordingly. PM2.5 levels during 2019–2021 of three representative air pollution monitoring stations (i.e., Chaing Mai-35T, Chiang Rai-57T, and Mae Sai-73T) in these two provinces were collected and analyzed. The Air Quality Index (AQI) defined by PM2.5 level higher than 91 µg m-3 causing serious adverse health effects was adopted to define periods having pollution levels, and the days of the air pollution episodes were identified. Based on these episodes, we applied the backward trajectory model to identify the sources of pollutants. Results showed that PM2.5 levels were significantly higher between February to April compared with other months during 2019–2021 at all three monitoring stations, indicating the severity of PM2.5 episode during the dry season. The backward trajectory demonstrated that air mass transported through the Northern Thailand or nearby mountain areas (categorized as long- or short-transport-distance) contributed up to 21.6% and 75.9% of the total air mass, respectively. Although residents in these mountainous areas are accustomed to the biomass burning, we suggested that there should be urgent needs for the improvement of the long-term air quality in these two provinces. Therefore, this study proposes some control strategies including improvement of prevention knowledge, increase of the risk perception, cultivation of the protection behavior, and intensification of the social influence. In addition to reducing biomass burning pollution, this improvement plan also has a co-benefit of achieving resources recycling concomitantly. Providing effective management strategies may reduce the adverse health effects to Thai residents.

Development of an Information System to Support Occupational Therapy Services from Hospital to Community

Background: Information systems for occupational therapy (OT) services need to adapt effectively for improving performance by taking advantage of digital technology. Objective: This research aimed to develop an information system for supporting occupational therapy services in the community. Methods: This study used a mixed methods research design divided into two phases. Phase I: system requirements were gathered from nine occupational therapists who represented each of the nine provinces in northern Thailand. Focus groups and in-depth interviews were used in detail to explore the system requirements for occupational therapy services in the community. This information system applied a responsive web design. Phase II: usability testing, involved thirty occupational therapists in a northern network, who were selected to evaluate an information system by using a questionnaire. Results: Results showed that participants requested two components: 1) Occupational Therapist data, and 2) a referral system. The information system could be used by occupational therapists in a northern Thai OT network to insert their own information actively for providing a referral system. The overall usability assessment was at a high level (mean ± SD = 4.27 ± 0.07). Conclusion: This study concluded that an OT digital network system may offer a strategy to support OT services from hospital to community in a complex system of healthcare.

Variation of Anthocyanin, Phenol, and Antioxidant Capacity in Straw among Rice Varieties and Growing Locations as a Potential Source of Natural Bioactive Compounds.

This study evaluated the variation in bioactive compounds (anthocyanins, phenols, and antioxidants) among 22 rice varieties in the same growing locations and among four varieties collected from eight different provinces in Northern Thailand. Wide variation in anthocyanins, phenols, and antioxidant capacity was established, ranging from 1.6 to 33.0 mg/100 g, 249.9 to 477.7 mg gallic acid/100 g, and 0 to 3,288.5 mg trolox equivalent/100 g, respectively. The highest straw anthocyanin and phenol concentrations were found in KDK (a traditional photoperiod-sensitive variety with purple pericarp and leaves) and K4 (an advanced, photoperiod-insensitive variety with purple pericarp and leaves), while the highest antioxidant capacity was found in KH CMU (an improved traditional photoperiod sensitive variety with a purple pericarp and green leaves) and K4. The variation of the bioactive compounds was also found in the same variety grown at different locations, e.g., the KDMl105 grown in Prayao province had a straw anthocyanin concentration higher than when grown in Mae Hong Son province. The effect was also observed in phenol content and antioxidant capacity when the same rice variety was grown across various locations. A significant correlation between total phenol and antioxidant capacity was observed across rice varieties and growing locations but was not found between anthocyanin and antioxidant capacity. This study found that the bioactive compounds in rice straw varied among rice varieties and growing locations. Straw phenol acts as a major antioxidant that can be used as a characteristic for the selection of rice varieties with high antioxidant capacity for use at the industrial scale for the processing of food, pharmaceuticals, and medicinal products.

Factors Affecting Oral Health Care Behavior of the Elderly Ethnic Groups in Rural Areas

Background: Elderly Hmong ethnic people in rural and remote communities in Thailand have a higher burden of oral health problems and poorer access to dental services than non-ethnic groups. Oral health offers clues about an individual’s overall health since problems in the mouth can affect the rest of the body. Objective: To study the oral health care behaviors and the association between related factors and oral health care. Materials and Methods: In the present study population-based, cross-sectional study, questionnaires were made by researchers from reviewing the literature, and in-depth interviews were conducted. Four hundred elderly Hmong people from rural areas located in lower northern Thailand participated in February 2021. First, the sample size was calculated by the Khazanie (1996) formula. Then, multi-stage random sampling using stratified random sampling of the Hmong populations in four provinces of northern Thailand was conducted along with simple random sampling of each province. Results: Data analyses involved descriptive statistics and multiple linear regression was used for the data analyses using the stepwise method. The results showed that participants had an overall moderate level of oral health care behavior at 65.5%. Age, congenital disease, knowledge, perception of benefits, perceived barriers of oral disease, social support from family, and the use of oral herbs were predictive oral health care behaviors (p<0.05). Seven variables can predict the oral health care behaviors of elderly Hmong people at 50.3% (R²=0.503, adjusted R²=0.494). Conclusion: The present study found that medical conditions had a negative effect on oral health care behaviors. These results could be used as guidelines to arrange additional activities for elderly Hmong people and integrate primary care alongside the oral health care. For further study, applying health promotion theories can be considered to encourage elderly Hmong people to exhibit positive behaviors. The use of an experimental design to assess the effects of a program focusing on the modification of seven predictors for changing oral health care behaviors among elderly Hmong people should also be considered. Keywords: Influencing; Behavior; Oral health; Hmong; Ethnic groups; Elderly people; Rural areas

Modelling Association between Production Practices and Business Performance of Northern Thailand OTOP Using Ordinal Logistic Regression

This study presents the model representing the association of the operational management practices of the OTOP producer to the business performance and revenue growth. This study used ordinal logistic regression to analyse the collected business performance data of 101 OTOP producers located in three northern provinces of Thailand. The production and operation management practices and their levels of adoption on the Production and Stock Management, Technology and Innovation adoption, Cost and Data and IT management assessed during the site visits were statistically modelled and tested for association with business performance. The ordinal logistic regression with nominal explanatory variables was used to identify the association between the OTOP business performance measured with the revenue growth and those production and operation practices. This analysis considers the different contexts of the different OTOP product groups. The association model was demonstrated in terms of the odd ratios and event probability of gaining higher revenue growth.

Genome-based analysis of infrequent Salmonella serotypes through the Thai pork production chain.

Salmonella is a prevalent zoonotic foodborne pathogen. Swine and pork are implicated as important sources of salmonellosis in humans. In Chiang Mai and Lamphun Provinces in northern Thailand, there has been a high prevalence of Salmonella persistence for over a decade. Infection is usually with dominant S. enterica serotypes, including serotypes Rissen and 1,4,[5],12:i:-. However, other serotypes also contribute to disease but are less well characterized. The whole genome sequencing data of 43 S. enterica serotypes isolated from pork production chain through 2011–2014, were used to evaluate genetic diversity and ascertain the possible source of Salmonella contamination based on Core Genome Multilocus Sequence Typing (cgMLST) approach. The Salmonella serotypes recovered from farms and slaughterhouses were re-circulating by swine environmental contamination. Conversely, the Salmonella contamination in the retail market represents cross-contamination from multiple sources, including contaminated foodstuffs. Salmonella contamination in the pork production chain has the competency for host cell adhesion, host cell invasion, and intracellular survival, which is enough for the pathogenicity of salmonellosis. In addition, all of these isolates were multi-drug resistant Salmonella, which contained at least 10 antimicrobial resistance genes. This result indicated that these S. enterica serotypes also pose a significant public health risk. Our findings support the need for appropriate surveillance of food-animal products going to market to reduce public exposure to highly pathogenic, multi-drug resistant Salmonella. Acquiring information would motivate all stakeholders to reinforce sanitation standards throughout the pork production chain in order to eradicate Salmonella contamination and reduce the risk of salmonellosis in humans.

Using the Health Belief Model to Predict Vaccination Intention Among COVID-19 Unvaccinated People in Thai Communities.

BackgroundThe coronavirus disease 2019 (COVID-19) pandemic has become one of the biggest challenges to individual health and the public health system worldwide. COVID-19 morbidity and mortality are increasing, impacting almost every country including Thailand. This study used the Health Belief Model (HBM) as a framework to examine the intention of unvaccinated people living in northern Thailand to receive COVID-19 vaccines.MethodsThis cross-sectional study was conducted during October and November 2021. A total of 1,024 participants who are currently living in four northern provinces of Thailand, Chiang Mai, Chiang Rai, Lamphun, and Phayao, were recruited to participate in the study. The questionnaire was developed using an HBM structure to obtain information about the perceived severity, perceived susceptibility, self-efficacy, perceived benefits and barriers, cues to action, and preventive behaviors relating to COVID-19 vaccination and the decision to become vaccinated. Multiple linear regression was used to analyze the data.ResultsThe unvaccinated participants were an average of 44.45 ± 16.63 years of age and more than half were women (54.5%). The COVID-19 preventive behavior score used perceived severity (B = 0.26), self-efficacy (B = 0.51), perceived benefits and barriers (B = 0.11), and cues to action (B = 0.18) after adjusting for age, underlying disease, and body mass index (R2 = 42.5%). The COVID-19 vaccination decision score was positively correlated with perceived severity (B = 0.13), perceived susceptibility (B = 0.25), perceived benefits and barriers (B = 0.21), and cues to action (B = 0.27) after adjusting for underlying disease (R2 = 38.7%).DiscussionThe results demonstrated the usefulness of using the HBM structure to understand individual intention to receive a COVID-19 vaccine. Communities should consider a COVID-19 health campaign and programs that use the HBM model as a framework for altering perceptions and beliefs about the COVID-19 vaccine and improving vaccination rates among unvaccinated people in rural northern Thailand.

Prediction of PM2.5 in an Urban Area of Northern Thailand Using Multivariate Linear Regression Model

As a result of considerable changes in rural areas in Northern Thailand, the frequency and intensity of haze outbreaks from particulate pollution, particularly fine particulate matter (PM2.5), has increased in this region. To supplement ground-based monitoring where PM2.5 observation is limited, this study applied a multivariate linear regression model to predict PM2.5 concentrations in 2020 using aerosol optical depth (AOD); meteorological parameters of wind velocity, temperature, and relative humidity; and gaseous pollutants such as SO2, NO2, CO, and O3 from ground-based measurements at three locations: Chiang Mai, Lampang, and Nan provinces in Northern Thailand. Two multivariate linear regression models were conducted in this study. The first model (model 1) is a generic model with meteorological parameters of aerosol optical depth (AOD), temperature, relative humidity, and wind speed. The second model (model 2) includes meteorological parameters and several gaseous pollutants, such as SO2, NO2, CO, and O3. In general, the regression model, which used hourly data from 2020 of the three provinces, adequately characterized the PM2.5 concentrations. The performance of model 2 was good for the prediction of PM2.5 concentrations at Chiang Mai (R2 = 0.52) and Lampang (R2 = 0.60). Model 2 improved the prediction of PM2.5 concentration compared to model 1 for both wet and dry seasons. However, model uncertainties were also present, which lays a foundation for further study.

Health Behavior, Level of Hemoglobin A1c, and Quality of Life Among Agricultural Workers of Various Ethnicities in Thai Border Communities.

BackgroundLittle is known about the glycated hemoglobin (HbA1c) levels and quality of life (QoL) in ethnic minority agricultural workers. We investigated the links among health behaviors, HbA1c levels, and QoL ethnic agricultural workers living in rural areas.MethodsA cross-sectional study was conducted in three northern Provinces of Thailand. Agricultural workers of Indigenous, Hmong, Karen, and Lua communities were recruited. The number of 468 samples were selected using multistage sampling. Data collection was done from interviews using questionnaires, and blood samples were taken.ResultsWe revealed 56.8% of participants to be female, with an average age of 49.6 years. Also, 56.0 and 34.8% of participants had low and moderate levels of knowledge on non-communicable diseases, respectively. In addition, 56.8 and 30.6% of participants had moderate and low health behaviors, respectively. Also, 51.5% had a HbA1c level (≥6.5%). We found that 64.7, 22.9, and 12.4% had moderate, low, and high QoL, respectively. Multiple linear regression analysis revealed that having an underlying disease and knowledge score were both significantly related to the health behaviors score (p < 0.05), accounting for 68.6% of the variance. Five variables (ethnicity, BMI, having an underlying disease, smoking, and health behaviors) were significantly related to the HbA1c level (p < 0.05), accounting for 24.6% of the variance. Education, health behaviors, and HbA1c level were significantly associated with QoL (p < 0.05). These three factors could explain 79.4% of the variance in QoL among ethnic agricultural workers.ConclusionHealth behaviors of ethnic minority agricultural workers influenced their HbA1c level and QoL. Effective health behaviors modification programs should be developed in accordance with the problems and needs among ethnic minority agricultural workers to enhance their QoL.

Improving Hill Farming: From Maize Monocropping to Alternative Cropping Systems in the Thai Highlands

Lately, the Hill Pond Rice System (HPRS) is being promoted as a form of alternative farming systems in selected northern provinces of Thailand, in which the land conversion is designed to maximize rainwater harvesting in farmland consisting of forest trees, water reservoirs, paddy fields, and high-value crop cultivation to serve environmental and livelihood needs. This study employed the double-hurdle model and the tobit technique to investigate the farm-level factors associated with land conversion from maize monocropping to the HPRS using primary data collected from 253 households in Nan, Chiang Mai, Tak, and Lampang Provinces. It was found that education, farming knowledge, understanding benefits of the HPRS, access to water sources, access to advis, and workforce sharing raised the likelihood and extent of farmland conversion into the HPRS. In contrast, perceived complexity of the HPRS, experiences with negative shocks, and land tenure security lowered the likelihood and extent of land conversion. The findings suggest that on-farm collective action should be promoted to mitigate labor constraints in implementation and that access to equipment should be enhanced through HPRS advisors’ visits.

Integration of breast cancer care in a middle-income country: learning from Suandok Breast Cancer Network (SBCN)

BackgroundBreast cancer incidence in Northern Thailand has shown a continuous increase since records began in 1983. In 2002 the urgency of the situation prompted Maharaj Nakorn Chiang Mai Hospital to initiate the Suandok Breast Cancer Network (SBCN).MethodsThe SBCN is a not-for-profit organization in the university hospital which serves as a training and education center and provides highly specialized medical care for patients in Chiang Mai and in 5 provinces of northern Thailand, with the key mission of improving breast cancer care. The short-term goal was to overcome the barriers to engagement with breast cancer and its treatment and the long-term goal was to increase the overall survival rate of breast cancer patients in our region.ResultsWe enrolled breast cancer patients treated at Maharaj Nakorn Chiang Mai Hospital between January 2006 and December 2015 and divided into 2 cohorts: 1485 patients who were diagnosed from 2006 to 2009 (cohort 1: early implementation of SBCN) and 2383 patients who were diagnosed from 2010 to 2015 (cohort 2: full implementation of SBCN). Criteria to measure improved cancer waiting time (CWT) would include: time to diagnosis, time to surgery, and time to radiotherapy. The 5-year overall survival (OS) of the cohort 2 was higher than that in cohort 1, at 73.8 (72.0–75.5) compared to 71.5 (69.2–73.7) (p-value = 0.03).ConclusionsReasons behind the success of project include the uniformity of care encouragement, service network development and timely access to each step of breast cancer management. The model used in SBCN could be adopted as a learning guide to improve healthcare access and outcome for breast cancer patients in low- to middle-income countries.

Storage fungi and ochratoxin A associated with arabica coffee bean in postharvest processes in Northern Thailand

Arabica coffee is one of the most popular varieties globally; however, during postharvest and storage, it can be contaminated by fungi which produce mycotoxins such as ochratoxin A (OTA). The goal of this study was to determine fungal contamination and OTA levels of arabica coffee produced from Chiang Rai and Chiang Mai provinces in Northern Thailand. Aspergillus and Penicillium were mainly isolated and evaluated from coffee samples in the postharvest process. Coffee cherries, parchment coffee, and green coffee beans were commonly found contaminated with fungi. Coffee beans were contaminated with Penicillium, Aspergillus section Flavi, Aspergillus section Nigri, and Aspergillus section Circumdati at 1.2–10%. Fungal contamination in parchment coffee was studied using three drying methods. The results showed that coffee dried in a greenhouse had higher fungal contamination than samples dried on concrete ground or on a bamboo table. Whether basic storage packaging of green coffee beans affects fungal contamination was also investigated. Green coffee beans in three packaging types showed similar levels of Penicillium, while of the three packaging types, coffee in a polypropylene woven bag showed significantly less Aspergillus than those in a ramie sack or a plastic mesh bag. Fourteen strains of Aspergillus section Circumdati were isolated from coffee samples and 5 isolates showed green-blue fluorescence under ultraviolet light suggesting a potential of OTA production. The morphology of Aspergillus section Circumdati isolates were studied and five isolates with similar morphological characters were further identified to the species level based on ITS and the β-tubulin gene regions. Sequencing and phylogenetic analysis suggested that four isolates were grouped with A. westerdijkiae and one isolate with A. melleus. Analysis of OTA in parchment coffee, green coffee beans, and roasted coffee was performed using HPLC. The results showed that OTA was detected in only one sample of roasted coffee at 0.39 μg kg−1.

3-Phase heuristics for capacitated multiple-depot vehicle routing problem with separate backhaul and linehaul with a case study on corn residue management system

The focus of this work is routing problems in which backhaul and linehaul customers are grouped to a depot, and where the total traveled distance of all routes is minimized. We propose an improved mathematical model for the multiple-depot capacitated vehicle routing problem. Under this modified model, each depot contains separate travel routes for backhaul and linehaul customers. We also propose a 3-phase heuristic based on greedy algorithm in the first 2 phases and on random search in the third phase to ensure reasonable execution time as well as to obtain a better local optimum. Solutions from the heuristic are compared to the optimal solution of small generated problems with up to 24 nodes. Then we compare the performance of the proposed heuristic with the most recent literature and discover that 3 out of 33 benchmark problems can be executed with better solutions. There are 10 problems whose objective function values are the same as the best solutions of the 5 referenced works while the remaining 20 problems are within 3% of those solutions. We also tackle 9 normal distribution benchmark problems with up to 1000 nodes with varying numbers of linehaul customers and depots. We apply the proposed heuristic and compare results with two recent heuristics on these 9 problems. We also solve, using the proposed heuristic, a real-world problem of a corn crop residue transportation system for 16 provinces in northern Thailand encompassing 974 corn fields, 127 co-ops, and 274 factories.

Automated survey of selected common plant species in Thai homegardens using Google Street View imagery and a deep neural network

Most previous studies of homegardens have used labor-intensive boots-on-the-ground plant surveys, owner questionnaires, and interviews, limiting them to at most a few hundred homegardens. We show that automated analysis of publicly available imagery can enable surveys of much greater scale that can augment these traditional data sources. Specifically, we demonstrate the feasibility of using the high-resolution street-level photographs in Google Street View and an object-detection network (RetinaNet) to create a large-scale high-resolution survey of the prevalence of at least six plant species widely grown in road-facing homegardens in Thailand. Our research team examined 4000 images facing perpendicular to the street and located within 10 m of a homestead, and manually outlined all perceived instances of eleven common plant species. A neural network trained on these tagged images was used to detect instances of these species in approximately 150,000 images constituting views of roughly one in every ten homesteads in five provinces of northern Thailand. The results for six of the plant species were visualized as heatmaps of both the average number of target species detected in each image and individual species prevalence, with spatial averaging performed at scales of 500 m and 2.5 km. Urban-rural contrasts in the average number of target species in each image are quantified, and large variations are observed even among neighboring villages. Spatial heterogeneity is seen to be more pronounced for banana and coconut than for other species. Star gooseberry and papaya are more frequently present immediately outside of towns while dracaena and mango persist into the cores of towns.

Culturable Bacterial Community on Leaves of Assam Tea (Camellia sinensis var. assamica) in Thailand and Human Probiotic Potential of Isolated Bacillus spp.

Assam tea plants (Camellia sinensis var. assamica) or Miang are found in plantations and forests of Northern Thailand. Leaf fermentation has been performed for centuries, but little information is available about their associated microbial community. One hundred and fifty-seven bacterial isolates were isolated from 62 Assam tea leaf samples collected from 6 provinces of Northern Thailand and classified within the phyla of Firmicutes, Actinobacteria, and Proteobacteria. Phayao and Phrae provinces exhibited the highest and the lowest bacterial diversities, respectively. The bacterial community structural pattern demonstrated significant differences between the west and the east sides. Since some Bacillus spp. have been reported to be involved in fermented Miang, Bacillus spp. isolated in this study were chosen for further elucidation. Bacillus siamensis ML122-2 exhibited a growth inhibitory effect against Staphylococcus aureus ATCC 25923 and MRSA DMST 20625, and the highest survival ability in simulated gastric and intestinal fluids (32.3 and 99.7%, respectively), autoaggregation (93.2%), cell surface hydrophobicity (50.0%), and bacterial adherence with Vero cells (75.8% of the control Lactiplantibacillus plantarum FM03-1). This B. siamensis ML122-2 is a promising probiotic to be used in the food industry and seems to have potential antibacterial properties relevant for the treatment of antibiotic-resistant infections.

Monitoring of the Organophosphate Pesticide Chlorpyrifos in Vegetable Samples from Local Markets in Northern Thailand by Developed Immunoassay.

Chlorpyrifos is an organophosphate pesticide that is wildly used among farmers for crop protection. However, there are concerns regarding its contamination in the environment and food chain. In the present study, an in-house indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) specific for detecting chlorpyrifos is developed and validated against gas chromatography–flame photometric detection (GC-FPD) as the conventional method. The developed ic-ELISA was used for detecting chlorpyrifos residue in vegetable samples. The developed ic-ELISA showed good sensitivity to chlorpyrifos at an IC50 of 0.80 µg/kg, with low cross-reactivity to other organophosphate pesticides. The 160 samples were collected from local markets located in the Chiang Rai, Chiang Mai, and Nan provinces in northern Thailand. The positive rate of chlorpyrifos residues in the vegetable samples was 33.8%, with the highest levels found in cucumbers, coriander, and morning glory, at 275, 145, and 35.3 µg/kg, respectively. The highest median levels of chlorpyrifos found in the detected samples were Chinese cabbage (332 μg/kg), cucumber (146.3 μg/kg) and Chinese Kale (26.95 μg/kg). The developed ic-ELISA is suitable for the rapid quantitation of chlorpyrifos residues.

Metal Concentrations and Source Apportionment of PM2.5 in Chiang Rai and Bangkok, Thailand during a Biomass Burning Season

One of the persistent environmental problems in the provinces of northern Thailand is severe air pollution during the dry season because of open vegetation burning by farmers for land clearance pur...