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This study attempted to develop carrageenan/chitosan based microparticles loading α-mangostin which was extracted from Vietnamese mangosteen skin. The carrageenan/chitosan/α-mangostin microparticles were prepared by ionic gelation method by mixing chitosan, carrageenan with α-mangostin and subsequently cross-linking the mixtures with sodium tripolyphosphate crosslinking agent. The content of α-mangostin in microparticles was changed to evaluate the effect of α-mangostin content on physical, morphological properties, particles size and bioactivities of the carrageenan/chitosan/α-mangostin microparticles. The obtained results showed that carrageenan, chitosan was interacted together and with α-mangostin. The presence of polymers matrix improved the release ability of α-mangostin into ethanol/pH buffer solutions. The carrageenan/chitosan/ α-mangostin microparticles have antibacterial (gram (+) strains) and anti-oxidant activities. The results suggested that combination of chitosan and carrageenan in the microparticles can enhance the control release of α-mangostin into solutions as well as keep the bioactivities of α-mangostin.

The present work presented a synthesis of silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) using the aqueous extract of waste banana stem (WBS), Musa paradisiaca Linn. The reduction and formation of MNPs have been characterized by several analysis techniques such as X-ray diffraction (XRD), Fourier transmission infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM). The techniques showed that average particle size of WBS-AgNPs and WBS-AuNPs in crystalline nature was in ranges of 7–13 nm and 11–14 nm, respectively. The synthesized nanoparticles were used to evaluate antibacterial activity and catalysis. The WBS-AgNPs showed strong antibacterial activity against B. subtilis and E. coli. The largest zone of inhibition against B. subtilis (14.2 mm) and E. coli (9.3 mm) was found at concentrations of 4.0 ppm and 2.0 ppm, respectively. The excellent catalytic application of both the nanoparticles for the reduction of 4-nitrophenol was confirmed via study on their kinetics. The normalized kinetic constants (knor) of WBS-AgNPs and WBS-AuNPs were found to be 1.72 × 10–3 s−1 mg−1 and 2.45 × 10–3 s−1 mg−1, respectively.

Despite the global zoonotic disease burden, the underlying exposures that drive zoonotic disease emergence are not understood. Here, we aimed to assess exposures to potential sources of zoonotic disease and investigate the demographics, attitudes, and behavior of individuals with sustained occupational animal contact in Vietnam. We recruited 581 animal workers (animal-raising farmers, slaughterers, animal health workers, and rat traders) and their families in southern and central Vietnam into a cohort. Cohort members were followed for 3 years and interviewed annually regarding (1) demography and attitudes regarding zoonotic disease, (2) medical history, (3) specific exposures to potential zoonotic infection sources, and (4) socioeconomic status. Interview information over the 3 years was combined and analyzed as cross-sectional data. Of the 297 cohort members interviewed, the majority (79.8%; 237/297) reported raising livestock; almost all (99.6%; 236/237) reported being routinely exposed to domestic animals, and more than a quarter (28.7%; 68/237) were exposed to exotic animals. Overall, 70% (208/297) reported slaughtering exotic animals; almost all (99.5%; 207/208) reported consuming such animals. The consumption of raw blood and meat was common (24.6%; 73/297 and 37%; 110/297, respectively). Over half (58.6%; 174/297) reported recent occupational animal-induced injuries that caused bleeding; the use of personal protective equipment (PPE) was limited. Our work demonstrates that individuals working with animals in Vietnam are exposed to a wide range of species, and there are limited procedures for reducing potential zoonotic disease exposures. We advocate better education, improved animal security, and enforced legislation of PPE for those with occupational animal exposure in Vietnam.