Fusarium solani PQF9 Isolated from Podocarpus pilgeri Growing in Vietnam as a New Producer of Paclitaxel.

Endophytic fungi are known as an alternative promising source of anticancer drug, paclitaxel, however fungi inhabiting in medicinal plant Podocarpus pilgeri and their paclitaxel production have not been reported to date. In the present study, a total of 15 culturable fungi classified into 5 genera, were successfully recovered from P. pilgeri collected in Vietnam. Screening fungal dichloromethane extracts for anticancer activity revealed that only PQF9 extract displayed potent inhibitory effects on A549 and MCF7 cancer cell lines with IC50 values of 33.9 ± 2.3 µg/mL and 43.5 ± 1.7 µg/mL, respectively. Through PCR-based molecular screening, the isolate PQF9 was found to possess 3 key genes involved in paclitaxel biosynthesis. Importantly, high-performance liquid chromatography quantification showed that fungal isolate PQF9 was able to produce 18.2 µg/L paclitaxel. The paclitaxel-producing fungus was identified as Fusarium solani PQF9 based on morphological and molecular phylogenetic analysis. Intensive investigations by chromatographic methods and spectroscopic analyses confirmed the presence of paclitaxel along with tyrosol and uracil. The pure paclitaxel had an IC50 value of 80.8 ± 9.4 and 67.9 ± 7.0 nM by using cell viability assay on A549 lung and MCF7 breast cancer cells. In addition, tyrosol exhibited strong antioxidant activity by scavenging 2, 2-diphenyl-picrylhydrazyl (DPPH) (IC50 5.1 ± 0.2 mM) and hydroxyl radical (IC50 3.6 ± 0.1 mM). In contrast, no biological activity was observed for uracil. Thus, the paclitaxel-producing fungus F. solani PQF9 could serve as a new material for large-scale production and deciphering paclitaxel biosynthesis. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-023-01119-z.

Characterization of a thermophilic cytochrome P450 of the CYP203A subfamily from Binh Chau hot spring in Vietnam.

Cytochromes P450 (CYPs or P450s) comprise a superfamily of heme-containing monooxygenases that are involved in a variety of biological processes. CYPs have broad utilities in industry, but most exhibit low thermostability, limiting their use on an industrial scale. Highly thermostable enzymes can be obtained from thermophiles in geothermal areas, including hot springs, offshore oil-producing wells and volcanoes. Here, we report the identification of a gene encoding for a thermophilic CYP from the Binh Chau hot spring metagenomic database, which was designated as P450-T2. The deduced amino acid sequence showed the highest identity of 73.15% with CYP203A1 of Rhodopseudomonas palustris, supporting that P450-T2 is a member of the CYP203A subfamily. Recombinant protein expression yielded 541 nm. The optimal temperature and pH of P450-T2 were 50 °C and 8.0, respectively. The half-life of P450-T2 was 50.2 min at 50 °C, and its melting temperature was 56.80 ± 0.08 °C. It was found to accept electrons from all tested redox partners systems, with BmCPR-Fdx2 being the most effective partner. Screening for putative substrates revealed binding of phenolic compounds, such as l-mimosine and emodin, suggesting a potential application of this new thermophilic P450 in the production of the corresponding hydroxylated products.

Occupational Stress Among Health Worker in a National Dermatology Hospital in Vietnam, 2018.

A cross-sectional study was conducted among 171 doctors and nurses in a National Dermatology hospital using the Karasek's Job Content Questionnaire which has been validated in Vietnamese (JCQ-V), to assess the prevalence of occupational stress and to explore the association with some associated factors among them. The result showed that doctors and nurses with occupational stress accounted for 6.4%. This proportion was higher among nurse compared to doctor (8.0% vs. 2.2%); among those with diploma literacy compared to bachelor and above (10.6% and 2.3%). This rate was also higher in health workers under 30 years old (12.9%), health workers under 5 years at work (12.1%), working night shift from 3-4 nights (33.3%), temporary employment (12.8%), heavy workload occasionally (12.5%), and working hard occasionally (17.2%) compared to those in the comparison groups with p value <0,05. This prevalence concentrated in some departments such as surgery (11.9%), internal medicine (6.7%), dermatology, and others (1.5%). The study has not found the significant association between the prevalence of occupational stress and heavy workload and skill level. Therefore, it is essential for hospital should conduct screening all doctors, nurses, and medical staffs to identify subjects having occupational stress and give appropriate intervention.

Attitudes toward nonsmoking policies and tobacco tax increases: a cross-sectional study among Vietnamese adults.

Following the 2009 update of the 2005 Framework Convention on Tobacco Control, Vietnam issued a new policy to ban smoking at workplaces and public places. This cross-sectional survey explored public attitudes toward this new regulation and provides evidence to inform future laws. Using stratified cluster sampling, 10 383 Vietnamese people older than 15 years were drawn from 11 142 selected households. Policies mandating "no smoking at workplaces" were supported by 88.7% of Vietnamese adults, whereas "no smoking in public places" and "increasing the tobacco tax" received less support. Educational level, knowledge of health effects, access to information on quitting and smoking health risks, smoking status, ethnicity, and region had significant associations with positive attitudes toward all 3 tobacco control policies. Adults belonging to the non-Kinh ethnic group, those who do not live in the Red river delta, people with lower educational levels, and current smokers should be targeted in tobacco control communication programs.

Sanitation behavior among schoolchildren in a multi-ethnic area of Northern rural Vietnam.

BACKGROUND: In Vietnam, efforts are underway to improve latrine use in rural and remote areas with particular focus on increasing coverage of sanitation in schools. However, there is a lack of information on how the school program affects latrine use by schoolchildren and at community level. This paper analyzes sanitation use among schoolchildren in a multi-ethnic area to inform future school-based sanitation promotion programmes. METHODS: A combination of quantitative and qualitative methods was applied during a 5 months period in six primary and secondary schools and in the homes of schoolchildren in four different ethnic villages in Northern rural Vietnam. Using a structured questionnaire, 319 children were interviewed face-to-face to collect quantitative data. Qualitative methods included extensive observations at schools and in the homes of 20 children, a single day's diary writings of 234 children, in-depth interviews with children (20), their parents (20) and school staff (10), and focus group discussions with parents (4) and teachers (6), and picture drawing with children (12). RESULTS: All surveyed schools had student latrines. However, the observed schoolchildren most commonly urinated and defecated in the open. Main barriers for latrine use included inadequate number of latrines, limited accessibility to latrines, lack of constant water supply in latrines and lack of latrine maintenance by school management. Programs promoting latrine use for children were not conducted in either schools or communities and were not established as a preferred social norm in such settings. Children perceived existing school latrines as unappealing and expressed a wish to have basic, functional, clean, and colorful school latrines with privacy. CONCLUSIONS: The paper shows that the current school based sanitation promotion is insufficient to change sanitation behavior of school children irrespective of their ethnicity. It is important that schools, households and communities work more closely together to increase use and uptake of latrine use among schoolchildren. Also, the contractors of latrine facilities must work more closely with local school management when constructing latrines, including identifying location, design and appropriate systems of water supply. A separate budget needs to be allocated to allow the school to maintain the sanitation infrastructure and keep it hygienic and appealing for users.