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Prediabetes is defined as a state of moderate hyperglycemia. Here, we used freeze-dried seeds of Stenocereus stellatus (white tunillo) as a possible therapeutic strategy for the treatment of prediabetes. In the aqueous extract of freeze-dried seeds of white tunillo, polyphenols were identified using the Folin-Ciocalteu technique, separated by UPLC and analyzed by infrared spectrophotometry. Five well-defined peaks with good resolution were observed in the chromatogram of the aqueous extract obtained by UPLC. Two of these peaks corresponded to polyphenols with similarity to quercetin and rutin. The subchronic oral administration of freeze-dried seeds of white tunillo for 14 days in a prediabetes model in female Wistar rats reversed hyperglycemia and glucose intolerance. Treatment with the freeze-dried seeds reversed the decrease in the hepatic expression of Akt, eNOS, and p-eNOSSer1177 but did not reverse the decrease in MnSOD, catalase, and GPx1. No changes in the expression of GPx4 and p-AktSer473 were observed in the pathological state or with the treatment but there was an increase in the expression and activity of eNOS. The bioactive compounds present in the freeze-dried seeds of Stenocereus stellatus could provide guidelines for studying the mechanisms of action through which they reverse signs of prediabetes.

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Aim: Benznidazole (BNZ), a class-II drug, is the primary treatment for Chagas disease, but its low aqueous solubility presents challenges in formulation and efficacy. Nanosuspensions (NS) could potentially address these issues.Methods: BNZ-NS were prepared using a simple, organic solvents-free nano-milling approach. Physicochemical characterizations were conducted on both NS and lyophilized solid-state BNZ-nanocrystals (NC).Results: BNZ-NS exhibited particle size <500 nm, an acceptable polydispersity index (0.23), high Z-potential, and physical stability for at least 90 days. BNZ-NC showed tenfold higher solubility than pure BNZ. Dissolution assays revealed rapid BNZ-NS dissolution. BNZ-NC demonstrated biocompatibility on an eukaryotic cell and enhanced BNZ efficacy against trypomastigotes of Trypanosoma cruzi.Conclusion: BNZ-NS offers a promising alternative, overcoming limitations associated with BNZ for optimized pharmacotherapy.

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With the increasing need to promote healthy and sustainable diets, seaweeds emerge as an environmentally friendly food source, offering a promising alternative for food production. The aim of this study was to characterize the brown seaweed Sargassum filipendula from the coast of São Paulo, Brazil, regarding its nutritional and techno-functional properties using two dehydration methods, oven drying and lyophilized. A commercial dried sample was used as a control. Analyses of proximate composition, mineral determination, amino acid determination, antioxidant capacity, pH, color, scanning electron microscopy, X-ray diffraction, thermal properties, Fourier-transform infrared spectroscopy, and techno-functional properties were performed. Seaweed flours showed significant differences in physicochemical composition, with dietary fiber content of seaweed flours exceeding 70 %. Glutamic and aspartic acids were the most abundant amino acids, with contents of 88.56 and 56.88 mg/g of protein in Sargassum oven drying. Both for antioxidant potential and bioactive compounds, Sargassum lyophilized flours showed the highest levels of compounds. Sargassum lyophilized exhibited lighter color compared to Sargassum oven drying and Sargassum commercial. Emulsion formation, foam formation capacity and stability were higher in Sargassum lyophilized, as well as water and oil absorption. The results suggest that seaweeds can be used to formulate a wide variety of food products, such as sausages, bread, cakes, soups, and sauces.

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This study evaluated the use of acerola (Malpighia glabra L., CACE), cashew (Anacardium occidentale L., CCAS), and guava (Psidium guayaba L., CGUA) fruit processing coproducts as substrates to promote the growth, metabolite production, and maintenance of the viability/metabolic activity of the probiotics Lactobacillus acidophilus LA-05 and Lacticaseibacillus paracasei L-10 during cultivation, freeze-drying, storage, and exposure to simulated gastrointestinal digestion. Probiotic lactobacilli presented high viable counts (≥8.8 log colony-forming units (CFU)/mL) and a short lag phase during 24 h of cultivation in CACE, CCAS, and CGUA. Cultivation of probiotic lactobacilli in fruit coproducts promoted sugar consumption, medium acidification, and production of organic acids over time, besides increasing the of several phenolic compounds and antioxidant activity. Probiotic lactobacilli cultivated in fruit coproducts had increased survival percentages after freeze-drying and during 120 days of refrigerated storage. Moreover, probiotic lactobacilli cultivated and freeze-dried in fruit coproducts had larger subpopulations of live and metabolically active cells when exposed to simulated gastrointestinal digestion. The results showed that fruit coproducts not only improved the growth and helped to maintain the viability and metabolic activity of probiotic strains but also enriched the final fermented products with bioactive compounds, being an innovative circular strategy for producing high-quality probiotic cultures.

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In proteomic studies, the reliability and reproducibility of results hinge on well-executed protein extraction and digestion protocols. Here, we systematically compared three established digestion methods for macrophages, namely filter-assisted sample preparation (FASP), in-solution, and in-gel digestion protocols. We also compared lyophilization and manual lysis for liver tissue protein extraction, each of them tested using either sodium deoxycholate (SDC)- or RIPA-based lysis buffer. For the macrophage cell line, FASP using passivated filter units outperformed the other tested methods regarding the number of identified peptides and proteins. However, a careful standardization has shown that all three methods can yield robust results across a wide range of starting material (even starting with 1 µg of proteins). Importantly, inter and intra-day coefficients of variance (CVs) were determined for all sample preparation protocols. Thus, the median inter-day CVs for in-solution, in-gel and FASP protocols were respectively 10, 8 and 9%, very similar to the median CVs obtained for the intra-day analysis (9, 8 and 8%, respectively). Moreover, FASP digestion presented 80% of proteins with a CV lower than 25%, followed closely by in-gel digestion (78%) and in-solution sample preparation (72%) protocols. For tissue proteomics, both manual lysis and lyophilization presented similar proteome coverage and reproducibility, but the efficiency of protein extraction depended on the lysis buffer used, with RIPA buffer showing better results. In conclusion, although each sample preparation method has its own particularity, they are all suited for successful proteomic experiments if a careful standardization of the sample preparation workflow is carried out.

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Lactobacillus delbrueckii subsp. bulgaricus and Lactiplantibacillus plantarum are two lactic acid bacteria (LAB) widely used in the food industry. The objective of this work was to assess the resistance of these bacteria to freeze- and spray-drying and study the mechanisms involved in their loss of activity. The culturability and acidifying activity were measured to determine the specific acidifying activity, while membrane integrity was studied by flow cytometry. The glass transitions temperature and the water activity of the dried bacterial suspensions were also determined. Fourier transform infrared (FTIR) micro-spectroscopy was used to study the biochemical composition of cells in an aqueous environment. All experiments were performed after freezing, drying and storage at 4, 23 and 37 °C. The results showed that Lb. bulgaricus CFL1 was sensitive to osmotic, mechanical, and thermal stresses, while Lpb. plantarum WCFS1 tolerated better the first two types of stress but was more sensitive to thermal stress. Moreover, FTIR results suggested that the sensitivity of Lb. bulgaricus CFL1 to freeze-drying could be attributed to membrane and cell wall degradation, whereas changes in nucleic acids and proteins would be responsible of heat inactivation of both strains associated with spray-drying. According to the activation energy values (47-85 kJ/mol), the functionality loss during storage is a chemically limited reaction. Still, the physical properties of the glassy matrix played a fundamental role in the rates of loss of activity and showed that a glass transition temperature 40 °C above the storage temperature is needed to reach good preservation during storage. KEY POINTS: • Specific FTIR bands are proposed as markers of osmotic, mechanic and thermal stress • Lb. bulgaricus CFL1 was sensitive to all three stresses, Lpb. plantarum WCFS1 to thermal stress only • Activation energy revealed chemically limited reactions ruled the activity loss in storage.

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Increasing the solubility of drugs is a recurrent objective of pharmaceutical research, and one of the most widespread strategies today is the formulation of nanocrystals (NCs). Beyond the many advantages of formulating NCs, their incorporation into solid dosage forms remains a challenge that limits their use. In this work, we set out to load Atorvastatin NCs (ATV-NCs) in a delivery device by combining 3D scaffolds with an "in situ" loading method such as freeze-drying. When comparing two infill patterns for the scaffolds at two different percentages, the one with the highest NCs load was chosen (Gyroid 20 % infill pattern, 13.8 ± 0.5 mg). Colloidal stability studies of NCs suggest instability in acidic media, and therefore, the system is postulated for use as a sublingual device, potentially bypassing stomach and hepatic first-pass effects. An ad hoc dissolution device was developed to mimic the release of actives. The nanometric size and properties acquired in the process were maintained, mainly in the dissolution rate and speed, achieving 100 % dissolution of the content in 180 s. Based on these results, the proof of concept represents an innovative approach to converting NCs suspensions into solid dosage forms.

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The microbial communities within honey bee colonies contribute to the defense against pathogens. The goal of this study was to isolate, identify, and lyophilize lactic acid bacteria and bifidobacteria from the gut of nurse bees and bee bread in Apis mellifera colonies. Bacterial cultures from the intestinal content were conducted, and subsequently identified, sequenced, and lyophilized. Cross-antagonism among them was also assessed. Studies based on 16 S rRNA gene Sanger sequencing revealed that the MC3 strain had 100% identity with Bifidobacterium choladohabitans, the PP2B strain showed 99.16% similarity with Enterococcus faecium, while the PP1 strain exhibited 99.49% similarity with Lacticaseibacillus sp. and the PP1B strain showed 99.32% similarity with Lacticaseibacillus sp. There was no evidence of cross-antagonism among the strains, and the lyophilization process showed good stability and conservation. This is the first report of the isolation of B. choladohabitans from honey bee gut in Argentina, and also associates the presence of E. faecium with bee bread.

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Molecular diagnostics involving nucleic acids (DNA and RNA) are regarded as extremely functional tools. During the 2020 global health crisis, efforts intensified to optimize the production and delivery of molecular diagnostic kits for detecting SARS-CoV-2. During this period, RT-LAMP emerged as a significant focus. However, the thermolability of the reagents used in this technique necessitates special low-temperature infrastructure for transport, storage, and conservation. These requirements limit distribution capacity and necessitate cost-increasing adaptations. Consequently, this report details the development of a lyophilization protocol for reagents in a colorimetric RT-LAMP diagnostic kit to detect SARS-CoV-2, facilitating room-temperature transport and storage. We conducted tests to identify the ideal excipients that maintain the molecular integrity of the reagents and ensure their stability during room-temperature storage and transport. The optimal condition identified involved adding 5% PEG 8000 and 75 mM trehalose to the RT-LAMP reaction, which enabled stability at room temperature for up to 28 days and yielded an analytical and diagnostic sensitivity and specificity of 83.33% and 90%, respectively, for detecting SARS-CoV-2. This study presents the results of a lyophilized colorimetric RT-LAMP COVID-19 detection assay with diagnostic sensitivity and specificity comparable to RT-qPCR, particularly in samples with high viral load.

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The present work aimed at the development and characterization of aroeira leaf flour (Schinus terebinthifolius Raddi), obtained by lyophilization and drying in an air circulation oven. The technological, physical, physico-chemical, morphological, functional, and microbiological aspects were analyzed. Physico-chemical analysis identified the following properties with values provided respectively for fresh leaves (FOin) and flours (FES and FLIO): low water activity (0.984, 0.370, 0.387 g/100 g), moisture (64.52, 5.37, 7.97 g /100 g), ash (2.69, 6.51, and 6.89 g/100 g), pH (0.89, 4.45, 4.48 g/100 g), lipids (0.84, 1.67, 5.23 g/100 g), protein (3.29, 8.23, 14.12 g/100 g), carbohydrates (17.02, 53.12, 33.02 g/100 g), ascorbic acid (19.70, 34.20, 36.90 mg/100 g). Sources of fiber from plant leaves and flours (11.64, 25.1, 32.89 g/100 g) showed increased levels of luminosity. For NMR, the presence of aliphatic and aromatic compounds with olefinic hydrogens and a derivative of gallic acid were detected. The most abundant minerals detected were potassium and calcium. Micrographs identified the presence of irregular, non-uniform, and sponge-like particles. The main sugars detected were: fructose, glucose, and maltose. Malic, succinic, citric, lactic, and formic acids were found. Fifteen phenolic compounds were identified in the samples, highlighting: kaempferol, catechin, and caffeic acid. The values ​​found for phenolics were (447, 716.66, 493.31 mg EAG/100 g), flavonoids (267.60, 267.60, 286.26 EC/100 g). Antioxidant activity was higher using the ABTS method rather than FRAP for analysis of FOin, FES, and FLIO. Since the flours of the aroeira leaf have an abundant matrix of nutrients with bioactive properties and antioxidant activity, they have a potential for technological and functional use when added to food.

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