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The synthesis of active films with natural antimicrobials from renewable sources offers an alternative to conventional non-biodegradable packaging and synthetic additives. This study aimed to develop cassava starch films with antimicrobial activity by incorporating either free carvacrol or chia mucilage nanocapsules loaded with carvacrol (CMNC) and assess their impact on the physical, mechanical, and barrier properties of the films, as well as their efficacy against foodborne pathogens. The addition of free carvacrol led to a reduction in mechanical properties due to its hydrophobic nature and limited interaction with the polymeric matrix. Conversely, CMNC enhanced elongation at break and reduced light transmission, with a more uniform distribution in the polymeric matrix. Films containing 8% carvacrol exhibited inhibitory effects against Salmonella and Listeria monocytogenes, further potentiated when encapsulated in chia mucilage nanocapsules. These findings suggest that such films hold promise as active packaging materials to inhibit bacterial growth, ensuring food safety and extending shelf life.

Este artigo tem por objetivo apresentar características de uma tarefa sobre Educação Financeira que possibilita a produção de significados na perspectiva do Modelo dos Campos Semânticos, do educador matemático Rômulo Campos Lins. A tarefa foi elaborada por Malheiros (2022) para estudantes do Ensino Médio e faz parte de um conjunto de tarefas que abordam a Educação Financeira de forma contextualizada e buscam desenvolver com os estudantes reflexões sobre as decisões financeiras a serem tomadas e os possíveis impactos nos contextos econômico, social e ambiental. Especificamente, são voltadas para o Planejamento Financeiro e abrangem endividamento, investimentos, organização, planejamento, uso do cartão de crédito, financiamentos, ferramentas digitais, poupança, inflação, consumismo e sustentabilidade. A partir da tarefa selecionada foi possível identificar quatro categorias que indicam um significativo potencial para que os estudantes produzam significados matemáticos e não matemáticos no contexto da Educação Financeira.

Objective: To evaluate the antifungal effect of Cinnamomum zeylanicum (C. zeylanicum) and Melaleuca alternifolia essential oils and honey against strains of Candida sp. from HIV-positive patients in order to subsidize new therapeutic strategies for candidiasis. Methods: The study evaluated the antifungal effect of natural antimicrobials against 30 strains of Candida sp. isolated from oral cavities in HIV-infected patients. Then, they were compared to the action of fluconazole and amphotericin B. Antifungal susceptibility was evaluated by the broth macrodilution technique and the minimum inhibitory concentration and the minimum fungicidal concentration were determined. Results: Among all antifungals evaluated in this study, amphotericin B was the one showing the best results; however, all compounds studied here showed inhibitory activities against isolates of Candida sp. Honey (0.0313–64 μg/mL) demonstrated fungistatic activity inhibiting 70% of the isolates. C. zeylanicum essential oil (0.0313–64 μg/mL) inhibited 93.3% of the Candida strains and Melaleuca alternifolia essential oil (0.0313–64 μg/mL) was able to inhibit 73.3% of them. Conclusions: Therefore, all natural compounds evaluated in this study, especially C. zeylanicum essential oil, may become promising agents for oral candidiasis therapy including in HIV-positive patients.

O objetivo deste trabalho foi isolar Staphylococcus aureus de manipuladores de alimentos de um lacticínio e determinar sua suscetibilidade a diversos antimicrobianos. Para tal, coletaram-se amostras a partir das mãos e cavidade nasal de 29 manipuladores. Foram obtidos 58 cultivos suspeitos, os quais foram submetidos a testes bioquímicos e ao teste de suscetibilidade aos antimicrobianos ciprofloxacina, oxacilina, penicilina G, clindamicina, tetraciclina, eritromicina, nitrofurantoína, sulfazotrim, rifampicina e vancomicina através da técnica de difusão em disco. Foram isoladas 19 cepas de S. aureus, sendo 42,10% provenientes das mãos e 57,90% da cavidade nasal dos indivíduos avaliados. O maior índice de resistência foi encontrado para penicilina G (78,95%), seguido pela tetraciclina (26,31%), enquanto que o maior índice de sensibilidade foi observado para nitrofurantoína, sulfazotrim, rifampicina e vancomicina (100%), seguido da oxacilina (94,73%) e ciprofloxacina (89,47%). De modo geral, as cepas apresentaram baixos níveis de resistência, entretanto, a presença de S. aureus nas mãos e cavidades nasais dos manipuladores desempenham papel importante na disseminação do micro-organismo.

Objective To evaluate the antifungal effect of Cinnamomum zeylanicum ( C. zeylanicum ) and Melaleuca alternifolia essential oils and honey against strains of Candida sp. from HIV-positive patients in order to subsidize new therapeutic strategies for candidiasis. Methods The study evaluated the antifungal effect of natural antimicrobials against 30 strains of Candida sp. isolated from oral cavities in HIV-infected patients. Then, they were compared to the action of fluconazole and amphotericin B. Antifungal susceptibility was evaluated by the broth macrodilution technique and the minimum inhibitory concentration and the minimum fungicidal concentration were determined. Results Among all antifungals evaluated in this study, amphotericin B was the one showing the best results; however, all compounds studied here showed inhibitory activities against isolates of Candida sp. Honey (0.0313–64 μg/mL) demonstrated fungistatic activity inhibiting 70% of the isolates. C. zeylanicum essential oil (0.0313–64 μg/mL) inhibited 93.3% of the Candida strains and Melaleuca alternifolia essential oil (0.0313–64 μg/mL) was able to inhibit 73.3% of them. Conclusions Therefore, all natural compounds evaluated in this study, especially C. zeylanicum essential oil, may become promising agents for oral candidiasis therapy including in HIV-positive patients. [ABSTRACT FROM AUTHOR]

Fungi are a problem for viticulture as they can lead to deterioration of grapes and mycotoxins production. Despite the widespread use of synthetic fungicides to control fungi, their impact on the agricultural ecosystem and human health demand safer and eco-friendly alternatives. This study aimed to produce, characterize and assess the antifungal activity of carvacrol loaded in nanocapsules of Eudragit® and chia mucilage as strategy for controlling Botrytis cinerea, Aspergillus flavus, Aspergillus carbonarius, and Aspergillus niger. Eudragit® and chia mucilage were suitable wall materials, as both favored the encapsulation of carvacrol into nanometric diameter particles. Fourier Transform Infrared Spectroscopy (FTIR) analysis suggested a successful incorporation of carvacrol into both nanocapsules, which was confirmed by presenting a good encapsulation efficiency and loading capacity. Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) analyses revealed adequate thermal resistance. All fungi were sensible to carvacrol treatments and B. cinerea was the most sensitive compared to the Aspergillus species. Lower concentrations of encapsulated carvacrol than the unencapsulated form were required to inhibit fungi in the in vitro and grape assays. Additionally, lower levels of carvacrol (unencapsulated or encapsulated) were used to inhibit fungal growth and ochratoxin synthesis on undamaged grapes in comparison to those superficially damaged, highlighting the importance of management practices designed to preserve berry integrity during cultivation, storage or commercialization. When sublethal doses of carvacrol were used, the growth of A. niger and A. carbonarius was suppressed by at least 45 %, and ochratoxins were not found. The nanoencapsulation of carvacrol using Eudragit® and chia mucilage has proven to be an alternative to mitigate the problems with fungi and mycotoxins faced by the grape and wine sector., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Carvacrol is a natural antimicrobial with excellent antimicrobial properties against several foodborne pathogens. Encapsulation can increase carvacrol stability and solubility, and mask its pronounced odor. Mucilages have been studied as wall material for nanoparticles due to their high retention capacity of bioactive compounds and ease of chemical modifications to improve their stability. In this study, 1.67 mg/mL of carvacrol encapsulated into chia mucilage nanoparticles (CMNP) and flaxseed mucilage nanoparticles (FMNP) were produced by high-energy emulsification technique and tested against Listeria monocytogenes and Salmonella. Encapsulation efficiency around 98% of carvacrol was obtained for both formulations. CMNP showed a diameter size of 179 nm and zeta potential of -11.4 mV. Bacterial Inactivation Concentration (BIC) of CMNP was 0.42 mg/mL against Salmonella and 0.83 mg/mL against L. monocytogenes. FMNP showed diameter size of 165.3 nm and zeta potential of -12.6 mV. BIC of FMNP was 0.83 mg/mL against both microorganisms. Scanning electron microscopy analysis showed that the nanoparticles are spherically shaped. Concentrations of BIC and ½ BIC were used to evaluate the kinetics of bacterial growth in the presence of antimicrobials (CMNP, FMNP and carvacrol solution). The results of this test showed that viable counts of Salmonella and L.monocytogenes were below the detection limit (1.69 log CFU/mL) after 2 h incubation (37 °C) using CMNP at the BIC. The wall material, rehydrated chia and flaxseed mucilages, reduced L. monocytogenes growth during 24 h. However, unloaded nanoparticles kept the viable counts of both microorganisms 2-5 log CFU/mL below the control curve of microbial growth during the 48 h experiment, suggesting that nanostructured mucilages potentiate antimicrobial properties. The results indicate that CMNP and FMNP have potential for use as food preservatives., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Carvacrol is a natural antimicrobial capable of inhibiting several microorganisms. The encapsulation of this compound may increase its stability, water solubility and provide controlled release. In this study, carvacrol encapsulated into nanoliposomes (NLC) and polymeric Eudragit® nanocapsules (NCC) was tested against Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Salmonella spp. adhered to stainless steel. NLC showed an average diameter of 270.8 nm, zeta potential of +8.64 mV, and encapsulation efficiency of 98%. Minimum Bactericidal Concentration (MBC) of NLC was 3.53 mg/mL against Salmonella and 5.30 mg/mL against the other bacteria. NCC presented an average diameter of 159.3 nm, zeta potential of +44.8 mV, and encapsulation efficiency of 97%. MBC of NCC was 4.42 mg/mL against E. coli and 3.31 mg/mL against the other bacteria. After 2 h incubation with NCC at carvacrol concentration equivalent to ½ MBC, viable counts of Salmonella and E. coli were below the detection limit (1.69 CFU/mL). The population of L. monocytogenes and S. aureus was reduced by 2 log CFU/mL in 6 h. Afterwards, pools of each bacterium were separately adhered to stainless steel coupons (initial population 6.5 CFU/cm 2 ). Salmonella and E. coli were inhibited below the detection limit using the NCC at concentration equivalent to MBC, while L. monocytogenes and S. aureus were reduced by 4 log CFU/cm 2 and 3.5 log CFU/cm 2 , respectively. Although free carvacrol presented better results than encapsulated one in all tests performed, using encapsulated carvacrol could be more interesting for food applications by masking the strong aroma of the compound, in addition to a controlled release of carvacrol. The results suggest that NCC have potential for use in food contact surfaces in order to avoid bacterial adhesion and subsequent biofilm formation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Antimicrobial activity of thymol, carvacrol and thymol/carvacrol liposomes (TCL) was evaluated against two bacterial pools, each one consisting of four strains of Staphylococcus aureus or Salmonella enterica. TCL were prepared using thin-film hydration, showing 270.20nm average diameter (polydispersity index of 0.33) and zeta potential of +39.99mV. Minimum inhibitory concentration (MIC) of thymol, carvacrol and TCL against S. aureus pool was 0.662mg/ml, while MIC for Salmonella pool was 0.331mg/ml for thymol and carvacrol, and for TCL was 0.662mg/ml. Bacterial pools (8.0logCFU/ml), allowed in contact on stainless steel AISI 304 coupons in UHT skim milk for 15min, resulted in adhered populations of 5.6-6.1logCFU/cm 2 . Adhered S. aureus (±6.1logCFU/cm 2 ) were inhibited after 1-min and 10-min treatments using thymol or carvacrol at MIC and 2.0 MIC. Reductions of 1.47-1.76logCFU/cm 2 and 1.87-2.04logCFU/cm 2 were obtained using 0.5 MIC of thymol and carvacrol, respectively. A 10-min contact with free (MIC and 2.0 MIC) and encapsulated (MIC) antimicrobials inhibited attached Salmonella (±6.0logCFU/cm 2 ); however, after 1-min of contact, 2.0 MIC of thymol and carvacrol were not able to inactivate adhered Salmonella MIC of TCL inactivated S. aureus and Salmonella after 10min; however, after 1-min contact, adhered S. aureus and Salmonella populations were decreased in 1.62logCFU/cm 2 and 2.01logCFU/cm 2 , respectively. Considering antimicrobial concentrations and contact times, thymol, carvacrol, and TCL could be employed in food-contact surfaces to prevent biofilm formation at early stages of bacterial attachment. Further investigations should be performed considering long-term antibacterial effects of TCL., (Copyright © 2017. Published by Elsevier B.V.)

Commercial nisin was encapsulated in nanovesicles (mean diameter 140 nm) prepared from partially purified soy lecithin. Nisin-loaded liposomes and unencapsulated (free) nisin were initially tested in BHI medium and skim milk inoculated with Listeria monocytogenes and incubated for 48 h at 30 degrees C. At such abuse temperature conditions, free nisin showed better inhibitory than the liposomal counterparts. Subsequently, the effect of encapsulated or free nisin was evaluated in combination with refrigeration (7 +/- 1 degrees C) in both whole (3.25% fat) and skim (0% fat) milk for up to 14 day. A decrease of 3-4 log cycles in L. monocytogenes counts was observed for free and encapsulated nisin at 0.5 mg/ml concentration. Liposome encapsulation of antimicrobial peptides may be important to overcome stability issues and interaction with food components. The utilization of nanovesicle-encapsulated nisin in combination with low temperatures appeared to be effective to control L. monocytogenes in milk, emphasizing the importance of hurdle technology to assure food safety.