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This study showed that a polylactide (PLA)-based composite filled with nanostructured hydroxyapatite (HAp) and a natural extract from the rhizome of Curcuma longa L. could provide an alternative to commonly used fossil-based plasticsfor food packaging. The incorporation of HAp into the PLA matrix had a positive effect on improving selected properties of the composites; the beneficial effect could be enhanced by introducing a green modifier in the form of an extract. Prior to the fabrication of the composite, the filler was characterized in terms of morphology and composition, and the composite was then fully characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman and Fourier transform infrared spectroscopy (FT-IR), and the mechanical, thermal, thermomechanical, and optical properties were investigated. The proposed material exhibits antioxidant properties against DPPH radicals and antibacterial performance against Escherichia coli (E. coli). The results showed that the nanocomposite has the highest antioxidant and antibacterial properties for 10 wt% HAp with an average diameter of rod-shaped structures below 100 nm. In addition, the introduction of turmeric extract had a positive effect on the tensile strength of the nanocomposites containing 1 and 5% HAp. As the resulting material adsorbs light in a specific wavelength range, it can be used in the medical sector, food-packaging, or coatings. [ABSTRACT FROM AUTHOR]

Antioxidants play an important role in the prevention of oxidative stress and have been widely used in medicine and healthcare. However, natural antioxidants have several limitations such as low stability, difficult long-term storage, and high cost of large-scale production. Along with significant advances in nanotechnology, nanomaterials have emerged as a promising solution to improve the limitations of natural antioxidants because of their high stability, easy storage, time effectiveness, and low cost. Among various types of nanomaterials exhibiting antioxidant activity, metal-based nanoantioxidants show excellent reactivity because of the presence of an unpaired electron in their atomic structure. In this review, we summarize some novel metal-based nanoantioxidants and classify them into two main categories, namely chain-breaking and preventive antioxidant nanomaterials. In addition, the applications of antioxidant nanomaterials in medicine and healthcare are also discussed. This review provides a deeper understanding of the mechanisms of metal-based nanoantioxidants and a guideline for using these nanomaterials in medicine and healthcare.

Antibiotic resistance and the transmission of resistance genes among bacteria in aquaculture are attracting world attention. The investigation was conducted to evaluate the antibiotic susceptibility of Aeromonas schubertii, which causes intensively cultured internal white spot disease in snakehead from An Giang province of the Mekong Delta. The findings isolated 29 bacterial strains from the kidney, spleen, and liver of diseased snakehead fish. Based on the morphological, biochemical, and 16S rRNA gene sequencing results, two strains of As9 and As11 showed a similarity of 98.71 % and 97.07 % to A. schubertii strains ZL-1 and GZ210812, respectively. The disc diffusion method was used to conduct antibiograms of the strains for 12 antibiotics. The research indicated that the bacteria were susceptible to the antibiotics ceftazidime, cefalexin, and doxycycline at rates of 86 %, 59 %, and 55 %, respectively. Meanwhile, bacteria were highly resistant to amoxicillin (93 %), flumequine (83 %), ciprofloxacin (76 %), rifampicin (66 %), erythromycin (62 %), colistin (59 %), florfenicol (59 %), and novobiocin (41 %). Interestingly, 100 % of the bacterial strains in the study demonstrated a multidrug-resistant phenotype, resistant to at least two antibiotics or more.

Abstract Vibrio parahaemolyticus is a significant causal agent of acute hepatopancreatic necrosis disease (AHPND), with huge production losses of white leg shrimp, Litopenaeus vannamei, cultivated globally, including aquaculture farms in the Mekong Delta of Vietnam. Controlling this disease is critical because of the worldwide expansion of antimicrobial‐resistant V. parahaemolyticus isolates. The purpose of this study was to determine the frequency of multi‐antibiotic resistance (MAR) in V. parahaemolyticus isolated from AHPND white leg shrimp extensively cultivated in Bac Lieu Province (Mekong Delta). Based on biochemical tests and toxR‐PCR positive detections, 34 V. parahaemolyticus isolates were identified. Antibiotic susceptibility examination revealed that most of the isolates were phenotypically multidrug resistant, including resistance to ceftazidime (100%) and amoxicillin (97.06%), followed by colistin (74%) and erythromycin (65%). These isolates were highly sensitive to doxycycline (94%), followed by florfenicol (74%) and flumequine (71%). There were 27 distinct MAR phenotypes detected among 34 isolates, with 14.71% of the isolates exhibiting the antibiotic profile AMO‐CEF‐CEP‐COL‐ERY, followed by 11.76% for each of the profiles AMO‐CEP‐TET‐COL and AMO–CEP–COL. In particular, 25 isolates (75%) were resistant to at least 5 (of the 12) antibiotics tested. A hierarchical clustering analysis of antibiotic‐resistant V. parahaemolyticus isolates indicated cross‐transmission across farms and its ability to survive in aquatic environments for extended periods (over 3 months). Our findings support the hypothesis that the variety of MARPs in V. parahaemolyticus is the result of human activities. Environmentally friendly therapy strategies should be used for the prophylaxis and treatment of V. parahaemolyticus infection.

The COVID-19 global pandemic has prompted governments to resort to or allow quasi-formal means to provide basic goods and services to communities that were forced into quarantine. We analyze how grassroots self-help strategies interact with the adaptation mechanisms of formal governance under crisis conditions. Drawing on empirical insights in Manila (Philippines) and Hanoi (Vietnam), we examine the practices that have enabled street vendors in the two metropolises to earn a living and to provide needed services to city residents. We explain how some lessons on co-production practices might inform post-pandemic recovery strategies and future policy-making processes in global South cities. [ABSTRACT FROM AUTHOR]

The diversity in structure and herbicidal properties detected in natural phytotoxic compounds could bring about advantages for development bio-herbicides. The present study was carried out search for potential weed inhibitors from the parts of Mimosa pigra L. The ethyl acetate (EtOAc) extract of leaf of M. pigra showed inhibitory activity during the time that Echinochloa crus-galli (barnyardgrass) germinates and grows, which is greater than that of other extracts. From this active extract, potent growth inhibitors were isolated and identified by column chromatography (CC), gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (1H and 13C NMR). The six compounds were purified in this study namely: lupeol (C1, 13.2 mg), stigmastane-3,6-dione (C2, 14.7 mg), quercetin (C3, 20.2 mg), chrysoeriol (C4, 28 mg), methyl gallate (C5, 21.5 mg) and daucosterol (C6, 16.0 mg). The C2 (quercetin) compound completely inhibited the emergency, shoot height and root length of E. crus-galli at 1 mg/mL concentration (IC50 shoot height = 0.56 mg/mL). This was also the first study to report the isolation and allelopathic activity of lupeol, chrysoeriol and daucosterol from M. pigra leaf. Findings of this study highlighted that quercetin from M. pigra may become bio-herbicide to control barnyard grass and other grass weeds for the development of safe agriculture.

Even though the demand for a nursing home is increasing, it is not easily-accepted in Vietnam because of cultural traditions which nomally link to morality, affection, relational cohesion, responsibility, relatives’ and friends’ opinions, etc. According to a study conducted by the Health Strategy and Policy Institute in 2012, Vietnamese people think that no one takes care of their parents better than children. That might be the reason why nursing home services have not developed well in Vietnam. This study aims to (1) explore attributes of nursing home preventing Vietnamese customers from using this service, and (2) explore the connections between these attributes and values of individuals through consequences from these attributes. The mean-end-chain theory with a soft-laddering interview is the method employed to conduct the study. Participants are persons who are responsible for making decisions related to nursing home matters, including elder people and ones having elder people in their families and being responsible to send their parents/grandparents to the nursing homes. The research findings show that there are 15 attributes of nursing home service, which drive to 4 values through 9 consequences, preventing Vietnamese customers from using this service. The result from the HVM states that there are three significant A-C-V linkages to explain what attributes and how they influence customers (perceived) values. The study also proposes some suggestions to promote nursing home service and encourage Vietnamese customers to accept this kind of service.

This paper aims to identify the level of student satisfaction with the quality of education in terms of four components: school curriculum, training courses in life skills, school facilities, and school management of educational programs. This study was based on a survey of 372 high school students from Ba Tri district in Ben Tre province. The estimated results from the regression analysis show that training management of schools and school facilities have a positive impact on student satisfaction. In addition, curriculum and training courses in life skills hardly have a positive influence on student satisfaction. In general, the findings enable school management to understand students’ mindsets and aspirations; thereby, they can make appropriate curriculum reform to improve the quality of education and enhance school prestige.

The purpose of this study was to evaluate the antioxidant, antibacterial, and anti-UVB of three kinds of fermented fruit peel extracts by pectinase enzyme, including pomegranate, pomelo, and banana peel. The antioxidant was evaluated by the DPPH (2,2-Diphenyl-1-picrylhydrazyl) free radical scavenging method. Antibacterial activity against Escherichia coli and Staphylococcus aureus was assessed by disk diffusion assay, and the photoprotective activity was measured using a photospectrometric method. The results revealed that pomegranate peel extract at 3000 IU/g peel exhibited potent free radical scavenging property against DPPH, with the smallest IC50 value at 0.18%, which was better than that of pomelo peel extract at 55.79%. Furthermore, the results suggested that the pomegranate peel extract also exhibited antibacterial activity against E. coli better than pomelo peel extract, but none of the three samples shows the antibacterial capacity against S. aureus. Moreover, 10% pomegranate peel extract also expressed the strongest anti-UVB activity, with an SPF value of 36.582. The research demonstrates pomegranate peel’s bioactivity potential for further experiments.

Hột sen thường hóa nâu nhanh chóng,sau khi được bóc vỏ. Phản ứng hóa nâu này do hai nguyên nhân cơ bản. Nguyên nhân thứ nhất không do enzyme gây ra. Nguyên nhân thứ hai là do enzyme peroxidase (POD). Để làm sáng tỏ ảnh hưởng gây hóa nâu do enzyme trên hột sen, hoạt tính tương đối của enzyme đã được khảo sát dựa theo nguyên tắc của phản ứng giữa guaiacol và H2O2 để tạo thành tetraguaiacol có màu nâu tím. Hoạt tính tương đối của enzymeđược tính bằng tốc độ tạo thành tetraguaiacol thông qua sự gia tăng độ hấp thu sau mỗi phút được đo bằng máy quang phổ ở bước sóng 470nm. Các dung dịch enzyme được trích ở các mức pH khác nhau từ 3,5 đến 8,5 và xử lý nhiệt từ 300C đến 800C trong 5 phút. Kết quả cho thấy enzyme POD trong hột sen hoạt động tốt nhất ở nhiệt độ 300C và trong dung dịch đệm phosphate có pH= 6. Hệ enzyme này bất hoạt hoàn toàn ở nhiệt độ từ 700C trở lên. ở pH 3,5 và 8,5 hoạt động của enzyme rất yếu.