Effects of seasoning on the formation of heterocyclic amines and polycyclic aromatic hydrocarbons in meats: A meta-analysis.

Cooking improves digestibility, palatability, and microbiological profile of meats, but can produce compounds with carcinogenic potential, such as heterocyclic amines (HAs) and polycyclic aromatic hydrocarbons (PAHs). It has been shown that the formation of these compounds in meats can be inhibited by spiced marinades, but there is a complexity to check and compare the results of isolated studies with so many variables involved. Thus, this work aimed to review studies that evaluated the effects of spices on the formation of HAs and PAHs in meats according to cooking techniques and spice type. A meta-analysis with a random effect model was conducted using response ratios (R) to identify and summarize previous results and answer the research question. The use of spices before frying (R* = 0.52), grilling (R* = 0.63), or roasting (R* = 0.74) meat, and spicing with garlic and onion (R* = 0.57), pepper (R* = 0.63), and other spices with phenolic compounds (R* = 0.63), decrease the formation of HAs and PAHs, due to the antioxidant and electron transfer capacity. In this article, we discuss how the improvement of culinary techniques with the dissemination of knowledge about meat preparation conditions is an effective strategy for reducing the formation and ingestion of HAs and PAHs; this is important due to the growing evidence about the association between meat consumption and chronic diseases. This is the first systematic review with meta-analysis about this topic and can guide industry, food services, and population to improve the safety associated with meat consumption.

Antimutagenic effect of an Asclepias subulata extract against heterocyclic aromatic amines commonly found in cooked meat and its heat stability.

The antimutagenicity of an extract from the medicinal plant Asclepias subulata (ASE) against heterocyclic aromatic amines (HAAs) commonly found in cooked meat, as well as its stability to heat treatment (HT), was evaluated. HT (180 °C/3 min) had no effect on the content in ASE of the bioactive compound corotoxigenin-3-O-glucopyranoside; conversely, calotropin significantly decreased by 72%. ASE exerted antimutagenicity against PhIP, MelQ, and MelQx in TA98 and TA100 Salmonella strains, and this activity was not affected by heat, with the exception of MelQ (p < 0.05). Since HAAs can induce colorectal cancer, the thermal stability of ASE's antiproliferative effect against colorectal cancer cells was also evaluated. HT decreased (p < 0.05) the antiproliferative activity of ASE; however, the remaining activity was still strong with an IC50 of 16.8 ± 2.03 µg/mL. Therefore, ASE can be used as a food ingredient to reduce the carcinogenic potential of thermally induced HAAs.

Estudos visando a síntese da macrosfelida (+)-A e síntese de anéis diidropirrólicos / Macrosfelide (+)-A and dihydropyrrol rings synthesis study

A primeira etapa deste trabalho refere-se à síntese da macrosfelida (+)-A, produto natural isolado da cultura de fungos Microsphaeropsis sp. FO5050, pertencente a uma classe de compostos que apresentam atividade antineoplásica. Para isso, foram utilizados sulfóxidos quirais, como indutores diastereosseletivos na síntese dos dois fragmentos propostos, A e B. A segunda parte deste trabalho refere-se a reações de ciclofuncionalização, utilizando iodo como eletrófilo. Na primeira etapa foram sintetizados compostos...

Hidrolise do terconazol: relacao estrutura-atividade / Hydrolysis of terconazole: chemical structure - biological activity relationship

Com o objetivo de contribuir para melhor entendimento da relacao entre estrutura quimica e a atividade biologica do terconazol, foi proposta a otimizacao da sua hidrolise. O isolamento e identificacao de produto resultante, cujas analises levam a crer que se trata da 1-(2,4-diclorofenil)-2-(1H-1,2-4-triazol-1-il)etanona (DFTE), sugerem que o terconazol sofre hidrolise no anel 1,3-dioxolanico (cetal ciclico), resultando em composto carbonilico. A DFTE mostrou-se ativa contra Candida albicans CBS 3156 e Escherichia coli ATCC 25922, nao apresentando atividade contra Staphylococcus aureus ATCC 25923. Estes resultados confirmam dados sobre o mecanismo de acao do terconazol e de outros compostos azolicos, tanto contra fungos e leveduras como contra bacterias

Conformational Equilibria in 1, 3-Azabicyclic Systems

La comparación de los parámetros de RMN'H para la perhidro-oxazolo (3,4-a) piridina (Jgem-2.5 Hz, delta4.40,3.81 ) con los 6-etilderivados 7 y 8, muestra la existencia de un equilibrio conformacional entre los conformadores trans-fusionado y el O-interno del cis-fusionado. La espectroscopia de RMN a bajas temperaturas permitió observar señales para ambos conformadores; y la integración de estas señales indican un equilibrio existente a 18ºK entre el 73 por ciento de 3-t y el 27 por ciento de 3-c