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The use of fungicides in the postharvest treatment of mangoes has been widespread due to the incidence of pathogens, but awareness of the health risks arising from their use has increased, driving the search for more sustainable treatments. This study aimed to evaluate the activity of antifungal treatment of seven essential oils (EO) against four fungi that cause postharvest diseases in mangoes and define the minimum inhibitory concentration (MIC) and chemical composition, analyzed by gas chromatography (GC-MS). The results showed that the EOs of oregano, rosemary pepper, cinnamon bark, and clove inhibited 100% of the mycelial growth of the studied pathogens, with MIC ranging from 250 to 2000 μL.L -1 . The main compound found in oregano was carvacrol (69.1%); in rosemary and pepper oil, it was thymol (77.2%); cinnamaldehyde (85.1%) was the main constituent of cinnamon bark, and the eugenol (84.84%) in cloves. When evaluating the antifungal activity of these compounds, thymol and carvacrol showed greater inhibitory activity against fungi. Therefore, this study showed the great potential of oregano, clove, rosemary pepper, and cinnamon bark essential oil as alternative treatments to synthetic fungicides in controlling postharvest diseases in mangoes., (© 2024. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

Objective: Considering that glucose is an important component of seminal plasma and is a cryoprotectant at high concentrations, the aim of this study was to investigate the possible association of glucose levels in fresh semen with the sperm survival and motility rates following cryopreservation., Methods: This was a prospective study including 149 men undergoing semen analysis due to male and/or female infertility. The seminal samples were analyzed according to the World Health Organization standards and glucose concentrations were measured using a dipstick glucometer. Samples were cryopreserved with Test Yolk Buffer-Gentamicine freezing medium under liquid nitrogen for an average of 120 days. The frozen aliquots were thawed at 37°C for 10 minutes and analyzed using the same methods and protocols used pre-freezing., Results: Glucose levels ranged from 14 to 99 mg/dL and were similar in individuals with normal (n=100) vs. abnormal (n=49) semen analysis. The rates of sperm recovery (total, alive or motile sperm) in the cryopreserved samples did not change among samples with different glucose levels (p>0.05, Kruskal-Wallis ANOVA and Spearman's correlation coefficient)., Conclusions: There appears to be no association between glucose levels in human semen samples and their resistance to cryopreservation.

The huge biological diversity of the Brazilian Cerrado is an important source of economically interesting microbial agents. The phylum Actinobacteria plays an important role in nutrient cycling, potentially improving their availability to plants. In this study, we isolated an actinobacteria (strain 3AS4) from wheat rhizospheres of crops cultivated in the Cerrado biome. Strain 3AS4 was identified as belonging to the genus Streptomyces and had phosphorus mobilization ability, mineralizing approximately 410 μg ml -1 from phytate, 300 μg ml -1 from calcium phosphate, and 200 μg ml -1 from rock phosphate. The analysis of the actinobacteria crude extract by spectrometric techniques revealed the presence of gluconic and 2-ketogluconic acid, and a greenhouse experiment was carried out to evaluate its plant growth promotion activity in soybean. Soil in its natural condition (with no phosphorus addition), 40 kg ha -1 rock phosphate from Bayovar (RP) added to soil, and triple super phosphate (SPT) added to soil were used. Significant differences in plant height were observed at 6 weeks when the plants were inoculated with the 3AS4 strain. The growth of inoculated plants in natural condition was promoted in 17% compared with the RP and SPT non-inoculated conditions, suggesting that inoculation can enable plants to grow with lower chemical P fertilizers. In the plants that were inoculated with the 3AS4 strain in the RP condition, the plant height increased by approximately 80% and the shoot:root ratio was approximately 30% higher compared to control conditions (non-inoculated plants in natural conditions). 3AS4 has P-solubilizing potential and can be exploited as an inoculant for soybean cultivation. These results suggest that this actinobacterium is a valuable resource for sustainable agriculture and will allow the reduction of phosphate fertilization in the future., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Vargas Hoyos, Chiaramonte, Barbosa-Casteliani, Fernandez Morais, Perez-Jaramillo, Nobre Santos, Nascimento Queiroz and Soares Melo.)

Intensive fish cultivation has a high incidence of infection, which is often controlled by administering antibiotics. Florfenicol (FF) is one of the two antimicrobial drugs permitted for aquaculture in Brazil. Due to their intensive use, potentially harmful effects on aquatic organisms are of great concern. In this sense, we investigated whether the presence of FF in cultivation water could change the health parameters of Nile tilapia. For this, we evaluated hemoglobin, hematocrit, mean corpuscular hemoglobin (MCHC) concentration, mean corpuscular volume (MCV), total plasma protein (TPP), number of circulating red blood cells and leukocytes, as lipid peroxidation levels, catalase activity and glutathione S-transferase activity of fish exposed to 11.72 mg L -1 of FF in water for 48 h. The fish were divided into two groups: Nile tilapia in water with FF or without FF (control). Exposure to FF in cultivation water for a short period didn't change the hematological variables analyzed, but caused changes in liver ROS (Reactive oxygen species) markers of the Nile tilapia, which was revealed by lipid peroxidation levels, catalase activity, and glutathione S-transferase. The 48h exposure period was enough to induce oxidative stress in hepatocytes, causing cellular oxidative damage. Therefore, the antibiotic florfenicol may cause toxicity to organisms and aquatic ecosystems, even at a sublethal concentrations near 1/100 LC50-48h for fish species., Competing Interests: The authors declare no conflict of interest., (© 2020 The Author(s).)

The process of freezing/thawing causes structural and functional damage to sperm samples, which can be mitigated by seminal plasma proteins. This study investigated the proposition that seminal protein measurements using a urinary dipstick prior to freezing could help predict the post-thaw recovery of live spermatozoa. This was a prospective study including 149 men undergoing semen analysis due to male and/or female infertility. The seminal samples were analysed according to World Health Organisation standards and protein concentrations were measured using a commercially available urinary dipstick following quantitative validation. The median live sperm recovery rates were 79%, 81% and 94%, respectively, in samples with protein concentrations of ≤1.0 g/L (+/++), 3.0 g/L (+++) and ≥20.0 g/L (++++) measured in fresh specimen dipstick analysis ( p  < 0.05) indicating that the probability of recovering at least 50% of frozen spermatozoa increased progressively with higher protein concentrations in the fresh sample (chi-square for linear association = 7.17. p  = 0.007). In conclusion, fresh seminal protein concentration levels assessed with a dipstick test correlate with the proportion of live spermatozoa recovered from cryopreserved samples. This simple, low-cost test may add prognostic information to baseline semen analysis prior to sperm banking.

Sulfamethazine (SMZ) is one of the most commonly used sulfonamide compounds in fish farming, and its physiological effects on fish are unknown. SMZ was administered to juvenile Nile tilapia (Oreochromis niloticus) at a dose level of 422 mg kg(-1) body weight, for a period of 11 days, via medicated feed. Fish were divided into two groups, the control group (CG) and the group fed with SMZ in feed. The administration of SMZ did not alter the erythrograms and leukograms of the Nile tilapia. The SMZ-fed group showed the same hepatic lipid peroxidation (LPO) concentration as the CG. Nonetheless, the oral administration of SMZ raised the hepatic catalase (CAT) and glutathione S-transferase (GST) activities, the increase probably being sufficient to prevent hepatic LPO production. The oral administration of SMZ affects the hepatic GST and CAT activities of Nile tilapia.