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Sausage is susceptible to oxidative changes in lipids and microbial spoilage due to the presence of water, fat, protein, and vitamins. Bee pollen (BP) as a source of potential antioxidants and antibacterial compounds can effectively prevent lipid peroxidation and microbial spoilage in meat products. The aim of the present study was to investigate the antibacterial and antioxidant activities of BP and the effects of nano/microparticles of bee pollen extract (n/m BP) at a concentration of 125 and 250 mg/100 g meat on the oxidative stability and microbial growth of high‐fat sausage during 30 days of storage at 4°C. The formation of BP particles in the nano/micro range was confirmed by scanning electron microscopy. High concentrations of total phenolic compounds (28.26 ± 0.10 mg GAE/g BP) with antioxidant activity (EC50 = 5.4 ± 0.07 mg/mL) were detected in BP. Based on the microdilution assay, the minimum inhibitory concentration of n/m BP for all test bacteria was 1000 (μg/mL) and the minimum bactericidal concentration of n/m BP was 2000 (μg/mL) for Staphylococcus aureus and Bacillus cereus and 4000 (μg/mL) for Escherichia coli and Pseudomonas aeruginosa. The n/m BP treatment (250 mg/100 g meat) showed a higher pH value (p <.05) and lower TBARS values (p <.05) than the ascorbic acid treatment (100 mg/100 g meat) and the control during the storage period. The microbial analysis showed that the addition of n/m BP led to a significant decrease (p <.05) in the total bacterial count, coliforms, S. aureus, and fungal population compared to the other samples. The results show that the addition of n/m BP (125 mg/100 g) can improve the texture, taste, and overall acceptability of the sausage compared to the control sample. In conclusion, this study suggests that BP can replace synthetic antioxidants in high‐fat sausages at the nano/microparticle level. [ABSTRACT FROM AUTHOR]

The riboflavin kinase in Methanocaldococcus jannaschii has been identified as the product of the M J0056 gene. Recombinant expression of the M J0056 gene in Escherichia coli led to a large increase in the amount of flavin mononucleotide (FMN) in the E. coli cell extract. The unexpected features of the purified recombinant enzyme were its use of CTP as the phosphoryl donor and the absence of a requirement for added metal ion to catalyze the formation of FMN. Identification of this riboflavin kinase fills another gap in the archaeal flavin biosynthetic pathway. Some divalent metals were found to be potent inhibitors of the reaction. The enzyme represents a unique CTP-dependent family of kinases.

Beta-tricalcium phosphate ( β-TCP) and anorthite are the main crystalline components in bone china bodies. The difference in their thermal expansion coefficients causes a decrease in the thermal shock resistance of the body. In this study, anorthite was replaced with bone ash in the bone china body, and the effect of this change was studied on different properties of bone china after si ntering at 1260°C for 3 h. The results showed that the physical and mechanical properties of the sample containing 50 wt.% anorthite compared to the typical bone china was improved and only 8.7% of the whiteness index was lost in this process. Also, the microstructure of anorthite samples, studied with SEM, showed no thermal cracks and revealed a uniform distribution of crystalline phase in the heterogeneous glass matrix. [ABSTRACT FROM AUTHOR]

Objective: During recent years, evidence-based practice as a way to support higher standards of care was emphasized by health care policymakers. Sexual dysfunction (SD) is a common problem that affects the quality of life in individuals. Today, the use of Ginkgo biloba extract (GBE) for treating SD has been considered, so this study was performed to evaluate the current evidence for the efficacy and safety of ginkgo in treating SD. Materials and Methods: In this review study, electronic databases of PubMed, Scopus, Cochrane, Google Scholar, Web of science and Persian databases such as SID and Magiran were searched up to March 2020, to identify all the studies reporting the effect of GBE for effectiveness on sexual function and its safety. The search was performed using the keywords of Ginkgo, Ginkgo biloba, Complementary and alternative medicine, women sexual dysfunction, and male sexual dysfunction. The quality of included studies was assessed using the Oxford Center for Evidence Based Medicine checklist. Results: Among 156 articles found in the initial search, 5 randomized controlled trials (475 participants) were selected for this study. After a meticulous review, we found that G. biloba can have positive effects on the sexual function of postmenopausal women, while evidence shows that it has no effect on the sexual function of antidepressants users. Headaches and gastrointestinal disturbance were among the adverse events mentioned in several trials. Conclusion: We concluded that G. biloba has limited positive effects on sexual function and more studies are needed to confirm these findings. [ABSTRACT FROM AUTHOR]

The identification and characterization of an archaeal FAD synthetase which catalyze the transfer of the AMP portion of ATP to FMN to produce FAD and pyrophosphate ([PP.sub.i]) is described. Compared to other FAD synthetases, the MJ1179-derived protein designated as RibL is not found to catalyze the reverse reaction to produce FMN and ATP from FAD and [PP.sub.i] and the activity of RibL was inhibited by [PP.sub.i].

The identification of a cyclic phosphodiesterase which have ability to hydrolyze the 7,8-Dihydro-D-neopterin 2',3'-cyclic phosphate ([H.sub.2]N-cP) and convert it to a mixture of 7,8-dihydro-D-neopterin 2'-monophosphate and 7,8-dihydro-D-neopterin 3'-monophosphate is reported. The direct metal analysis of the recombinant enzyme from Methanocaldococcus jannachii designated as MptB demonstrated that MptB contained 1.0 mol of zinc and 0.8 mol of iron per protomer and required [Fe.sup.2+] for activity similar to one observed for MptA.

7,8-Dihydro-D-neopterin 2',3'-cyclic phosphate (H2N-cP) is the first intermediate in biosynthesis of the pterin portion of tetrahydromethanopterin (H4MPT), a C1 carrier coenzyme first identified in the methanogenic archaea. This intermediate is produced from GTP by MptA (MJ0775 gene product), a new class of GTP cyclohydrolase I [Grochowski, L. L., Xu, H., Leung, K., and White, R. H. (2007) Biochemistry 46, 6658-66671. Here we report the identification of a cyclic phosphodiesterase that hydrolyzes the cyclic phosphate of H2N-cP and converts it to a mixture of 7,8-dihydro-D-neopterin 2'-monophosphate and 7, 8-dthydro-D-neoptertn 3'-monophosphate. The enzyme from Methanocaldococcus jannachii is designated MptB (MJ0837 gene product) to indicate that it catalyzes the second step of the biosynthesis of methanopterin. MptB is a member of the HD domain superfamily of enzymes, which require divalent metals for activity. Direct metal analysis of the recombinant enzyme demonstrated that MptB contained 1.0 mol of zinc and 0.8 mol of iron per protomer. MptB requires Fe2+ for activity, the same as observed for MptA. Thus the first two enzymes involved in H4MPT biosynthesis in the archaea are Fe2+ dependent. [ABSTRACT FROM AUTHOR]

Dysregulation of energy balance leading to obesity is a significant risk factor for cardiometabolic diseases such as diabetes, non-alcoholic fatty liver disease and atherosclerosis. In rodents and several other vertebrates, feeding has been shown to induce a rapid rise in the intestinal levels of N-acyl-ethanolamines (NAEs) and the chronic consumption of a high fat diet abolishes this rise. Administering NAEs to rodents consuming a high fat diet reduces their adiposity, in part by reducing food intake and enhancing fat oxidation, so that feeding-induced intestinal NAE biosynthesis appears to be critical to appropriate regulation of energy balance. However, the contribution of feeding-induced intestinal NAE biosynthesis to appropriate energy balance remains poorly understood in part because there are multiple enzymes that can contribute to NAE biosynthesis and the specific enzyme(s) that are responsible for feeding-induced intestinal NAE biosynthesis have not been identified. The rate-limiting step in the intestinal biosynthesis of NAEs is formation of their immediate precursors, the N-acyl-phosphatidylethanolamines (NAPEs), by phosphatidylethanolamine N-acyltransferases (NATs). At least six NATs are found in humans and multiple homologs of these NATs are found in most vertebrate species. In recent years, the fecundity and small size of zebrafish (Danio rerio), as well as their similarities in feeding behavior and energy balance regulation with mammals, have led to their use to model key features of cardiometabolic disease. We therefore searched the Danio rerio genome to identify all NAT homologs and found two additional NAT homologs besides the previously reported plaat1, rarres3, and rarres3l, and used CRISPR/cas9 to delete these two NAT homologs (plaat1l1 and plaat1l2). While wild-type fish markedly increased their intestinal NAPE levels in response to a meal after fasting, this response was completely ablated in plaat1l1 -/- fish. Furthermore, plaat1l1 -/- fish fed a standard flake diet had increased weight gain and glucose intolerance compared to wild-type fish. The results support a critical role for feeding-induced NAPE and NAE biosynthesis in regulating energy balance and suggest that restoring this response in obese animals could potentially be used to treat obesity and cardiometabolic disease., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: During recent years, evidence-based practice as a way to support higher standards of care was emphasized by health care policymakers. Sexual dysfunction (SD) is a common problem that affects the quality of life in individuals. Today, the use of Ginkgo biloba extract (GBE) for treating SD has been considered, so this study was performed to evaluate the current evidence for the efficacy and safety of ginkgo in treating SD., Materials and Methods: In this review study, electronic databases of PubMed, Scopus, Cochrane, Google Scholar, Web of science and Persian databases such as SID and Magiran were searched up to March 2020, to identify all the studies reporting the effect of GBE for effectiveness on sexual function and its safety. The search was performed using the keywords of Ginkgo, Ginkgo biloba , Complementary and alternative medicine, women sexual dysfunction, and male sexual dysfunction. The quality of included studies was assessed using the Oxford Center for Evidence Based Medicine checklist., Results: Among 156 articles found in the initial search, 5 randomized controlled trials (475 participants) were selected for this study. After a meticulous review, we found that G. biloba can have positive effects on the sexual function of postmenopausal women, while evidence shows that it has no effect on the sexual function of antidepressants users. Headaches and gastrointestinal disturbance were among the adverse events mentioned in several trials., Conclusion: We concluded that G. biloba has limited positive effects on sexual function and more studies are needed to confirm these findings., Competing Interests: The authors have declared that there is no conflict of interest.