Postharvest control of Rhizopus stolonifer on blackberry (Rubus fruticosus) by blackberry native crop bacteria

The potential of four native bacterial strains of blackberries cv. Brazos (Rubus fruticosus): Bacillus subtilis (BSS), Bacillus subtilis (BSL), Bacillus licheniformis (BLI) and Leifsonia aquatica (LAQ), was evaluated for the postharvest control of soft rot caused by Rhizopus stolonifer in blackberry fruits. The fruits were treated with cell suspensions (CS) and cell-free supernatants (CFE) from each bacterial strain and were infected with two strains of R. stolonifer (RSA and RSC). The severity and inhibition percentage of the disease were determined. Additionally, the inhibition by siderophores and the inhibition percentage of R. stolonifer spore germination were analyzed as possible control mechanisms. The CS of BSS inhibited RSA by 45.8%, followed by CFE of LAQ which controlled the same strain by 39.7%. The CS of BLI inhibited RSC by 37.7%, whereas the CFE of BSS and LAQ controlled it by 47.7 and 41.8%, respectively. All bacterial strains inhibited RSA and RSC by siderophores production (38.7 to 48.6 %) and the inhibition of spore germination of RSC was higher than 93% after 48 h. This work is one of the first to report R. stolonifer control by native bacteria CS and CFE, particularly LAQ in postharvested blackberry fruits. These results show the combination of mechanisms used by bacteria to control both R. stolonifer strains.The potential of four native bacterial strains of blackberries cv. Brazos (Rubus fruticosus): Bacillus subtilis (BSS), Bacillus subtilis (BSL), Bacillus licheniformis (BLI) and Leifsonia aquatica (LAQ), was evaluated for the postharvest control of soft rot caused by Rhizopus stolonifer in blackberry fruits. The fruits were treated with cell suspensions (CS) and cell-free supernatants (CFE) from each bacterial strain and were infected with two strains of R. stolonifer (RSA and RSC). The severity and inhibition percentage of the disease were determined. Additionally, the inhibition by siderophores and the inhibition percentage of R. stolonifer spore germination were analyzed as possible control mechanisms. The CS of BSS inhibited RSA by 45.8%, followed by CFE of LAQ which controlled the same strain by 39.7%. The CS of BLI inhibited RSC by 37.7%, whereas the CFE of BSS and LAQ controlled it by 47.7 and 41.8%, respectively. All bacterial strains inhibited RSA and RSC by siderophores production (38.7 to 48.6 %) and the inhibition of spore germination of RSC was higher than 93% after 48 h. This work is one of the first to report R. stolonifer control by native bacteria CS and CFE, particularly LAQ in postharvested blackberry fruits. These results show the combination of mechanisms used by bacteria to control both R. stolonifer strains

Dissecting the Influence of Two Structural Substituents on the Differential Neurotoxic Effects of Acute Methamphetamine and Mephedrone Treatment on Dopamine Nerve Endings with the Use of 4-Methylmethamphetamine and Methcathinone Running Title: Neurotoxici

Abstract: 244 words Introduction: 737 word

Long access heroin self-administration significantly alters gut microbiome composition and structure

Introduction: It is well known that chronic opioid use disorder is associated with alterations in gastrointestinal (GI) function that include constipation, reduced motility, and increased bacterial translocation due to compromised gut barrier function. These signs of disrupted GI function can be associated with alterations in the gut microbiome. However, it is not known if long-access opioid self-administration has effects on the gut microbiome.Methods: We used 16S rRNA gene sequencing to investigate the gut microbiome in three independent cohorts (N=40 for each) of NIH heterogeneous stock rats before onset of long-access heroin self-administration (i.e., naïve status), at the end of a 15-day period of self-administration, and after post-extinction reinstatement. Measures of microbial α- and β-diversity were evaluated for all phases. High-dimensional class comparisons were carried out with MaAsLin2. PICRUSt2 was used for predicting functional pathways impacted by heroin based on marker gene sequences.Results: Community α-diversity was not altered by heroin at any of the three phases by comparison to saline-yoked controls. Analyses of β-diversity showed that the heroin and saline-yoked groups clustered significantly apart from each other using the Bray-Curtis (community structure) index. Heroin caused significant alterations at the ASV level at the self-administration and extinction phases. At the phylum level, the relative abundance of Firmicutes was increased at the self-administration phase. Deferribacteres was decreased in heroin whereas Patescibacteria was increased in heroin at the extinction phase. Potential biomarkers for heroin emerged from the MaAsLin2 analysis. Bacterial metabolomic pathways relating to degradation of carboxylic acids, nucleotides, nucleosides, carbohydrates, and glycogen were increased by heroin while pathways relating to biosynthesis of vitamins, propionic acid, fatty acids, and lipids were decreased.Discussion: These findings support the view that long access heroin self-administration significantly alters the structure of the gut microbiome by comparison to saline-yoked controls. Inferred metabolic pathway alterations suggest the development of a microbial imbalance favoring gut inflammation and energy expenditure. Potential microbial biomarkers and related functional pathways likely invoked by heroin self-administration could be targets for therapeutic intervention