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Bacterial infections have become a global concern, stimulating the growing demand for natural and biologically safe therapeutic agents with antibacterial action. This study was evaluated the genotoxicity of the trypsin inhibitor isolated from tamarind seeds (TTI) and the antibacterial effect of TTI theoric model, number 56, and conformation number 287 (TTIp 56/287) and derived peptides in silico. TTI (0.3 and 0.6 mg.mL−1) did not cause genotoxicity in cells (p > 0.05). In silico, a greater interaction of TTIp 56/287 with the Gram-positive membrane (GP) was observed, with an interaction potential energy (IPE) of −1094.97 kcal.mol−1. In the TTIp 56/287-GP interaction, the Arginine, Threonine (Thr), and Lysine residues presented lower IPE. In molecular dynamics (MD), Peptidotrychyme59 (TVSQTPIDIPIGLPVR) showed an IPE of −518.08 kcal.mol−1 with the membrane of GP bacteria, and the Thr and Arginine residues showed the greater IPE. The results highlight new perspectives on TTI and its derived peptides antibacterial activity. [ABSTRACT FROM AUTHOR]

The study aimed to prospect in silico native and analogous peptides with anti-SARS-CoV-2 potential derived from the trypsin inhibitor purified from tamarind seeds (TTIp). From the most stable theoretical model of TTIp (TTIp 56/287), in silico cleavage was performed for the theoretical identification of native peptides and generation of analogous peptides. The anti-SARS-CoV-2 potential was investigated through molecular dynamics (MD) simulation between the peptides and binding sites of transmembrane serine protease 2 (TMPRSS2), responsible for the entry of SARS-CoV-2 into the host cell. Five native and analogous peptides were obtained and validated through chemical and physical parameters. The best interaction potential energy (IPE) occurred between TMPRSS2 and one of the native peptides obtained by cleavage with trypsin and its analogous peptide. Thus, both peptides showed many hydrophobic residues, a common physical–chemical property among the peptides that inhibit the entry of enveloped viruses, such as SARS-CoV-2, present in specific drugs to treat COVID-19. [ABSTRACT FROM AUTHOR]

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Vitamin E is important because of its antioxidant activity in situations of oxidative stress, especially postnatally. Hence, the objective was to verify whether maternal alpha‐tocopherol level is associated with the alpha‐tocopherol levels of the newborn and colostrum. This is a cross‐sectional study of 58 women and their term newborns from a public hospital. Blood and colostrum were collected to measure alpha‐tocopherol levels by high‐performance liquid chromatography. Mothers with serum alpha‐tocopherol levels <16.2 mmol L−1 and newborns <11.6 mmol L−1 were indicative of deficiency or low levels. Mothers were divided into two groups: <16.2 mmol L−1 and those with levels ≥16.2 mmol L−1. The mean (95% confidence interval) serum alpha‐tocopherol levels of mothers, umbilical cords and colostrum were 28 (24–32), 6 (5–8) and 39 mmol L−1 (32–45), respectively (P < 0.001); 19% of the women and 90% of the newborns had low alpha‐tocopherol levels. Maternal alpha‐tocopherol level was associated with that of the umbilical cord. Newborns from mothers at risk of deficiency had low alpha‐tocopherol levels (P < 0.001). Colostrum levels of vitamin E were not influenced by maternal serum. Maternal deficiency influenced the vitamin E level of the umbilical cord but does not in the colostrum, evidencing distinct transfer mechanisms via the mammary gland. [ABSTRACT FROM AUTHOR]

Objectives: To determine the alpha-tocopherol concentration in breast milk at different periods of lactation and to estimate the possible supply of vitamin E to the infant., Methods: A longitudinal observational study was carried out with 100 mothers at University Hospital Ana Bezerra (HUAB), at Universidade Federal do Rio Grande do Norte, in Santa Cruz (RN), Northeast Brazil. Samples of colostrum (n=100), transitional milk (n=77), and mature milk (n=63) were collected. Alpha-tocopherol was analyzed by high-performance liquid chromatography. Vitamin supply to the newborn was estimated by comparing the nutritional requirement of vitamin E (4 mg/day) with the potential daily intake of milk., Results: The mean alpha-tocopherol concentration found in colostrum, transitional, and mature milk was 40.5±15.0 µmol/L, 13.9±5.2 µmol/L, and 8.0±3.8 µmol/L, respectively (p<0.001). The possible effect of these milks offered to the infant 6.2 mg/day of vitamin E in colostrum, 4.7 mg/day in transitional milk, and 2.7 mg/day in mature milk (p<0.0001), shows that only the mature milk did not guarantee the recommended quantity of this vitamin., Conclusions: Alpha-tocopherol levels in human milk decrease through the progression of lactation, and the possible intake of colostrum and transitional milk met the nutritional requirement of the infant. Mature milk may provide smaller amounts of vitamin E. Thus, it is important to study the factors that are associated with such low levels.

Purpose: To determine the nutritional status of vitamin E in breastfeeding women through the analysis of alpha-tocopherol concentration in serum and colostrum, to analyze its relation with maternal variables and to determine the prevalence of vitamin E deficiency in these women., Methods: The study included 103 mothers who were classified according to maternal variables: age, nutritional status before pregnancy, gestational weight gain, parity and mode of delivery. Colostrum and serum samples were collected under fasting conditions in the immediate postpartum period. Alpha-tocopherol was analyzed by high performance liquid chromatography (HPLC). A serum cutoff of 697.7 μg/dL was adopted to define the nutritional status of vitamin E. Statistical analysis was performed with the Student's t test for independent samples and Pearson's correlation. Differences were significant when p<0.05., Results: The average concentration of alpha-tocopherol was 1.125±551.0 μg/dL in colostrum and 1,138.6±346.0 μg/dL in serum, indicating adequate biochemical nutritional status. However, when analyzing the mothers individually, a 16% rate of subclinical vitamin E deficiency was detected. Women undergoing cesarean delivery had significantly higher alpha-tocopherol levels in colostrum (1.280±591 μg/dL) compared with those undergoing normal delivery (961.7±370 μg/dL) (p<0.05). It was found that mothers who were overweight before pregnancy had higher vitamin concentration in colostrum (1,331.5±548 μg/dL) when compared to underweight women (982.1±374 μg/dL) or women of normal weight (992.3±346 μg/dL) (p<0.05). However, the other variables were not associated with alpha-tocopherol in colostrum. Moreover, no variable showed association with vitamin E levels in maternal serum and no correlation was demonstrated between the alpha-tocopherol levels in serum and in milk., Conclusions: Despite the diagnosis of satisfactory nutritional status, breastfeeding women showed significant risk of subclinical vitamin E deficiency. We suggest that the concentration of alpha-tocopherol in colostrum be associated with type of delivery and pre-gestational nutritional status of women.