The Cardiorenal Effects of Piper amalago Are Mediated by the Nitric Oxide/Cyclic Guanosine Monophosphate Pathway and the Voltage-Dependent Potassium Channels.

Piper amalago L. is used in Brazilian traditional medicine to treat inflammation, chest pain, and anxiety. This study aimed to investigate the safety and the renal and cardiovascular effects of the volatile oil (VO) and the aqueous (AE) and hydroalcoholic (HE) extracts from P. amalago. The gas chromatography-mass spectrometry analyses identified 47 compounds in the VO, with ß-cyclogermacrene, spathulenol, ß-phellandrene, and α-pinene standing out. Among the 47 compounds also found in AE and HE by liquid chromatography-mass spectrometry, glycosylated flavones, organic acids, amino acids, and amides were highlighted. Some examples of these compounds are methoxy-methylenedioxy cis-cinnamoyl pyrrolidine, methoxy-methylenedioxy trans-cinnamoyl pyrrolidine, and cyclobutene-2,4-bis-(1,3-benzodioxol-5-methoxy-6-yl)-1,3-dicarboxapyrrolidide. The acute toxicity experiments were conducted on female rats (n = 5). The cardiorenal assays (n = 8) and evaluations of vasodilatory effects on the mesenteric vascular bed (n = 5) were conducted on male rats. In either extract or VO, there were no mortality or changes in relative weights or histopathological analysis of the organs. Urinary volume and renal electrolyte excretion were elevated significantly during repeated dose 7-day treatment with different preparations from P. amalago. None of the preparations induced hypotension or changes in cardiac electrical activity. Only HE promoted significant vasodilatory effects in rats' isolated mesenteric vascular beds. These effects were completely abolished in the presence of L-NAME plus 4-aminopyridine. Therefore, P. amalago leaves are safe and present diuretic activity after acute and repeated dose administration over 7 days. Moreover, the HE induced significant vasodilator response in rats' mesenteric vascular beds by NO/cGMP pathway and voltage-dependent K+ channels activation.

Genomic and Phenotypic Insights Into the Potential of Rock Phosphate Solubilizing Bacteria to Promote Millet Growth in vivo.

Rock phosphate (RP) is a natural source of phosphorus for agriculture, with the advantage of lower cost and less impact on the environment when compared to synthetic fertilizers. However, the release of phosphorus (P) from RP occurs slowly, which may limit its short-term availability to crops. Hence, the use of P-solubilizing microorganisms to improve the availability of P from this P source is an interesting approach, as microorganisms often perform other functions that assist plant growth, besides solubilizing P. Here, we describe the characterization of 101 bacterial isolates obtained from the rhizosphere and endosphere of maize plants for their P solubilizing activity in vitro, their growth-promoting activity on millet plants cultivated in soil amended with RP, and their gene content especially associated with phosphate solubilization. For the in vitro solubilization assays, two mineral P sources were used: rock phosphate from Araxá (Brazil) mine (AP) and iron phosphate (Fe-P). The amounts of P released from Fe-P in the solubilization assays were lower than those released from AP, and the endophytic bacteria outperformed the rhizospheric ones in the solubilization of both P sources. Six selected strains were evaluated for their ability to promote the growth of millet in soil fertilized with a commercial rock phosphate (cRP). Two of them, namely Bacillus megaterium UFMG50 and Ochrobactrum pseudogrignonense CNPMS2088, performed better than the others in the cRP assays, improving at least six physiological traits of millet or P content in the soil. Genomic analysis of these bacteria revealed the presence of genes related to P uptake and metabolism, and to organic acid synthesis. Using this approach, we identified six potential candidates as bioinoculants, which are promising for use under field conditions, as they have both the genetic potential and the experimentally demonstrated in vivo ability to improve rock phosphate solubilization and promote plant growth.

Eugenol Induces Phenotypic Alterations and Increases the Oxidative Burst in Cryptococcus.

Eugenol is a phenolic compound and the main constituent of the essential oil of clove India. Although there are reports of some pharmacological effects of eugenol, this study is the first that proposes to evaluate the antifungal effects of this phenol against both Cryptococcus gattii and C. neoformans cells. The effect of eugenol against yeast cells was analyzed for drug susceptibility, alterations in cell diameter, capsule properties, amounts of ergosterol, oxidative burst, and thermodynamics data. Data demonstrated that there is no interaction between eugenol and fluconazole and amphotericin B. Eugenol reduced the cell diameter and the capsule size, increased cell surface/volume, changed positively the cell surface charge of cryptococcal cells. We also verified increased levels of reactive oxygen species without activation of antioxidant enzymes, leading to increased lipid peroxidation, mitochondrial membrane depolarization and reduction of lysosomal integrity in cryptococcal cells. Additionally, the results showed that there is no significant molecular interaction between eugenol and C. neoformans. Morphological alterations, changes of cellular superficial charges and oxidative stress play an important role in antifungal activity of eugenol against C. gattii and C. neoformans that could be used as an auxiliary treatment to cutaneous cryptococcosis.

Long-Term Rock Phosphate Fertilization Impacts the Microbial Communities of Maize Rhizosphere.

Phosphate fertilization is a common practice in agriculture worldwide, and several commercial products are widely used. Triple superphosphate (TSP) is an excellent soluble phosphorus (P) source. However, its high cost of production makes the long-term use of crude rock phosphate (RP) a more attractive alternative in developing countries, albeit its influence on plant-associated microbiota remains unclear. Here, we compared long-term effects of TSP and RP fertilization on the structure of maize rhizosphere microbial community using next generation sequencing. Proteobacteria were dominant in all conditions, whereas Oxalobacteraceae (mainly Massilia and Herbaspirillum) was enriched in the RP-amended soil. Klebsiella was the second most abundant taxon in the RP-treated soil. Burkholderia sp. and Bacillus sp. were enriched in the RP-amended soil when compared to the TSP-treated soil. Regarding fungi, Glomeromycota showed highest abundance in RP-amended soils, and the main genera were Scutellospora and Racocetra. These taxa are already described as important for P solubilization/acquisition in RP-fertilized soil. Maize grown on TSP and RP-treated soil presented similar productivity, and a positive correlation was detected for P content and the microbial community of the soils. The results suggest changes of the microbial community composition associated to the type of phosphate fertilization. Whilst it is not possible to establish causality relations, our data highlights a few candidate taxa that could be involved in RP solubilization and plant growth promotion. Moreover, this can represent a shorter path for further studies aiming the isolation and validation of the taxa described here concerning P release on the soil plant system and their use as bioinoculants.

In silico Prediction, in vitro Antibacterial Spectrum, and Physicochemical Properties of a Putative Bacteriocin Produced by Lactobacillus rhamnosus Strain L156.4.

A bacteriocinogenic Lactobacillus rhamnosus L156.4 strain isolated from the feces of NIH mice was identified by 16S rRNA gene sequencing and MALDI-TOF mass spectrometry. The entire genome was sequenced using Illumina, annotated in the PGAAP, and RAST servers, and deposited. Conserved genes associated with bacteriocin synthesis were predicted using BAGEL3, leading to the identification of an open reading frame (ORF) that shows homology with the L. rhamnosus GG (ATCC 53103) prebacteriocin gene. The encoded protein contains a conserved protein motif associated a structural gene of the Enterocin A superfamily. We found ORFs related to the prebacteriocin, immunity protein, ABC transporter proteins, and regulatory genes with 100% identity to those of L. rhamnosus HN001. In this study, we provide evidence of a putative bacteriocin produced by L. rhamnosus L156.4 that was further confirmed by in vitro assays. The antibacterial activity of the substances produced by this strain was evaluated using the deferred agar-spot and spot-on-the lawn assays, and a wide antimicrobial activity spectrum against human and foodborne pathogens was observed. The physicochemical characterization of the putative bacteriocin indicated that it was sensitive to proteolytic enzymes, heat stable and maintained its antibacterial activity in a pH ranging from 3 to 9. The activity against Lactobacillus fermentum, which was used as an indicator strain, was detected during bacterial logarithmic growth phase, and a positive correlation was confirmed between bacterial growth and production of the putative bacteriocin. After a partial purification from cell-free supernatant by salt precipitation, the putative bacteriocin migrated as a diffuse band of approximately 1.0-3.0 kDa by SDS-PAGE. Additional studies are being conducted to explore its use in the food industry for controlling bacterial growth and for probiotic applications.

Macaúba (Acrocomia aculeata) cake from biodiesel processing: a low-cost substrate to produce lipases from Moniliella spathulata R25L270 with potential application in the oleochemical industry.

BACKGROUND: Biodiesel industry wastes were evaluated as supplements for lipase production by Moniliella spathulata R25L270, which is newly identified yeast with great lipolytic potential. Macaúba cake (MC), used for the first time in this work as inducer to produce lipases, and residual oil (RO) were mixed to maximise enzyme production. The lipase secreted was biochemically characterised. RESULTS: The best ratio for the mixture (MC:RO) was 0.66:0.34 and the fitted values for lipase activity and total protein concentration were 0.98 U mL(-1) and 0.356 mg mL(-1), respectively. Maximum activity obtained (2.47 U mL(-1)) was achieved at 31.5°C and pH 6.7, and the enzyme was stable in this condition. A novel enzyme was purified and identified for the first time by mass spectrometry. The lipase efficiently hydrolysed different natural oils and exhibited selectivity in the production of eicosapentaenoic acid from fish oil. CONCLUSION: The use of MC and RO as a supplement to produce the new lipase from M. spathulata R25L270 may be one alternative for reducing lipase production costs and simultaneously adding value to biodiesel industry residues. The potential application of the lipase in the oleochemical industry was demonstrated by its pH and temperature stabilities and selective hydrolysis.

Lipolytic potential of Aspergillus japonicus LAB01: production, partial purification, and characterisation of an extracellular lipase.

Lipolytic potential of Aspergillus japonicus LAB01 was investigated by describing the catalytic properties and stability of a secreted extracellular lipase. Enzyme production was considered high under room temperature after 4 days using sunflower oil and a combination of casein with sodium nitrate. Lipase was partially purified by 3.9-fold, resulting in a 44.2% yield using ammonium sulphate precipitation (60%) quantified with Superose 12 HR gel filtration chromatography. The activity of the enzyme was maximised at pH 8.5, and the enzyme demonstrated stability under alkaline conditions. The optimum temperature was found to be 45°C, and the enzyme was stable for up to 100 minutes, with more than 80% of initial activity remaining after incubation at this temperature. Partially purified enzyme showed reasonable stability with triton X-100 and was activated in the presence of organic solvents (toluene, hexane, and methanol). Among the tested ions, only Cu(2+), Ni(2+), and Al(3+) showed inhibitory effects. Substrate specificity of the lipase was higher for C14 among various p-nitrophenyl esters assayed. The KM and V max values of the purified enzyme for p-nitrophenyl palmitate were 0.13 mM and 12.58 umol/(L·min), respectively. These features render a novel biocatalyst for industrial applications.