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This paper aims to provide a contribution to understanding the role of sludge macro-components (lipids, proteins and carbohydrates) on the yield/quality of bio-crude obtained via hydrothermal liquefaction (HTL). This was pursued by analysing the HTL process of real sludges and the mixtures thereof at different compositions, a topic that has been explored in a very limited way in the pertinent literature. The HTL experiments were run with municipal sludge, tannery sludge and a mixture of them in 25:75, 50:50 and 75:25 weight ratios in a batch reactor at 350 °C and for different residence times. The outcomes for a single sludge showed a greater bio-crude yield for the municipal one (42.5% at 10 min), which is linked to its significant carbohydrate content. The results obtained from the sludge mixtures suggested that a carbohydrate-to-protein mass ratio of 2:1 would maximise the bio-crude yield (average value of about 38%). Moreover, LC-MS and NMR analyses highlighted that the mixed sludges contributed to the formation of a higher number of compounds after the HTL treatment, with respect to the pure municipal or tannery sludge, with an increase in amine, alcohols and aromatic compounds. [ABSTRACT FROM AUTHOR]

Compared to single microbial strains, complex interactions between microbial consortia composed of various microorganisms have been shown to be effective in expanding ecological functions and accomplishing biological processes. Electroactive microorganisms (EMs) and degradable microorganisms (DMs) play vital roles in bioenergy production and the degradation of organic pollutants hazardous to human health. These microorganisms can strongly interact with other microorganisms and promote metabolic cooperation, thus facilitating electricity production and pollutant degradation. In this review, we describe several specific types of EMs and DMs based on their ability to adapt to different environments, and summarize the mechanism of EMs in extracellular electron transfer. The effects of interactions between EMs and DMs are evaluated in terms of electricity production and degradation efficiency. The principle of the enhancement in microbial consortia is also introduced, such as improved biomass, changed degradation pathways, and biocatalytic potentials, which are directly or indirectly conducive to human health.

Stomata are microscopic openings that allow for the exchange of gases between plants and the environment. In Arabidopsis, stomatal patterning is specified by the ERECTA family (ERf) receptor kinases (RKs), the receptor-like protein (RLP) TOO MANY MOUTHS (TMM), and EPIDERMAL PATTERNING FACTOR (EPF) peptides. Here we show that TMM and ER or ER-LIKE1 (ERL1) form constitutive complexes, which recognize EPF1 and EPF2, but the single ERfs do not. TMM interaction with ERL1 creates a binding pocket for recognition of EPF1 and EPF2, indicating that the constitutive TMM-ERf complexes function as the receptors of EPF1 and EPF2. EPFL9 competes with EPF1 and EPF2 for binding to the ERf-TMM complex. EPFL4 and EPFL6, however, are recognized by the single ERfs without the requirement of TMM. In contrast to EPF1,2, the interaction of EPFL4,6 with an ERf is greatly reduced in the presence of TMM. Taken together, our data demonstrate that TMM dictates the specificity of ERfs for the perception of different EPFs, thus functioning as a specificity switch for the regulation of the activities of ERfs. [ABSTRACT FROM AUTHOR]

Compared to single microbial strains, complex interactions between microbial consortia composed of various microorganisms have been shown to be effective in expanding ecological functions and accomplishing biological processes. Electroactive microorganisms (EMs) and degradable microorganisms (DMs) play vital roles in bioenergy production and the degradation of organic pollutants hazardous to human health. These microorganisms can strongly interact with other microorganisms and promote metabolic cooperation, thus facilitating electricity production and pollutant degradation. In this review, we describe several specific types of EMs and DMs based on their ability to adapt to different environments, and summarize the mechanism of EMs in extracellular electron transfer. The effects of interactions between EMs and DMs are evaluated in terms of electricity production and degradation efficiency. The principle of the enhancement in microbial consortia is also introduced, such as improved biomass, changed degradation pathways, and biocatalytic potentials, which are directly or indirectly conducive to human health., (© 2023 The Author(s).)

In blood vessels, nitric oxide homeostasis is maintained by its formation by endothelial nitric oxide synthase and its consumption in smooth muscle cells and in vascular lumen by red blood cell (RBC) encapsulated hemoglobin (Hb). Free hemoglobin has a very high reaction rate ( kHb–NO ~ 107 M−1 s−1) with NO as compared to RBC–Hb. Mechanisms of reduced NO uptake by RBC–Hb has been extensively studied in recent years. A critical factor in the investigation of NO–RBC interactions is delivery of NO. Common NO delivery methods include use of NO donors and bolus saturated NO solutions, which delivers NO homogenously and only in the vicinity of bolus, respectively. In this study, we developed a flow system that uses gaseous delivery of NO through a polymeric semi-permeable membrane to obtain precise and uniform NO concentrations for NO–RBC interactions. We conducted experiments using the flow system to study the effect of NO concentrations, hematocrit and RBC suspension flow rates on NO–RBC interactions. We developed a computational model to simulate NO transport and to estimate the reaction rate constant for NO–RBC interaction in the flow system. Our results showed that NO consumption of RBCs (i) increased linearly with an increase in available NO, and (ii) decreased with increase in RBCs suspension flow rate. We estimated the reaction rate constant for NO–RBC interactions to be 0.2 × 105 M−1 s−1 which is ~1250-fold lower than NO consumption by free hemoglobin and ~2.5–20 fold slower than reported NO–RBC reaction rate. [ABSTRACT FROM AUTHOR]

The phytotoxicity of shoot leachates of selected plant species was assessed on germination, and on shootcut and seedling bioassays of Parthenium hysterophorus. Shoot leachates of selected plant species were effective in inhibiting germination of Parthenium seeds, with Azardirachta indica the most effective. Shoot growth was inhibited most, and shoots damaged the most, by leachates of Solanum nigrum. [ABSTRACT FROM AUTHOR]

One of the main challenges to the research on allelopathy is technically the separation of allelopathic effect from competition, and quantitatively, the assessment of the contribution of each component to overall interference. A simple mathematical model is proposed to calculate the contribution of allelopathy and competition to interference. As an example of applying the quantitative model to interference by barley (Hordeum vulgare cv. Triumph), the approach used was an addition of allelopathic effect, by an equivalent amount, to the environment of the test plant (white mustard, Sinapis alba), rather than elimination of competition. Experiments were conducted in glasshouse to determine the magnitude of the contributions of allelopathy and competition to interference by barley. The leachates of living barley roots significantly reduced the total dry weight of white mustard. The model involved the calculation of adjusted densities to an equivalent basis for modelling the contribution of allelopathy and competition to total interference. The results showed that allelopathy contributed 40%, 37% and 43% to interference by barley at 6, 12 and 18 white mustard pot. The consistency in magnitude of the calculated contribution of allelopathic effect by barley across various densities of receiver plant suggested that the adjusted equivalent density is effective and that the model is able to assess the contribution of each component of interference regardless of the density of receiver plant. [ABSTRACT FROM AUTHOR]

Toxicity of organophosphates stems mainly from the accumulation of acetylcholine due to inhibition of acetylcholinesterase (AChE). The consequences of excess acetylcholine depend on the events initiated by the interaction of acetylcholine with cholinergic receptors. Lipid peroxidation (LPO) induced by organophosphates also seems to be mediated via cholinergic receptors. Anilofos is a widely used thionoorganophosphate herbicide, while malathion is a thionoorganophosphate insecticide. Thionoorganophosphates undergo mixed function oxidase (MFO)-catalyzed bioactivation to oxons and can induce cholinergic crisis in mammals. Thus, factors (e.g. exposure to certain xenobiotics) which alter the MFO activity, can be assumed to affect the toxicity of these organophosphates. It was investigated in rats if malathion as an inhibitor of MFO can alter the toxicity of anilofos, examining certain biochemical traits in blood, brain and liver. Malathion or anilofos and their combination did not produce any obvious signs of toxicity. Malathion did not alter the anticholinesterase action of anilofos in blood, brain and liver. LPO was increased in erythrocytes, brain and liver with anilofos or malathion and their combination. Production of lipid peroxide in brain of malathion-pretreated rats given anilofos was significantly greater than in rats given anilofos alone. Malathion decreased glutathione (GSH) contents of liver and blood. Glutathione-S-transferase (GST) activity was decreased in the liver with malathion and its combination with anilofos. Total adenosine triphosphatase (ATPase) activity was not affected. Activities of Mg2+-ATPase and Na+–K+-ATPase were increased in the liver and erythrocytes, respectively, with the pesticide combination. Protein level in plasma was decreased with malathion and its combination with anilofos, but only with the combination in the liver. Results of the study indicate that malathion pretreament may not essentially alter the anticholinesterase action of anilofos, but may enhance anilofos-mediated oxidative damage to rat brain. [Copyright &y& Elsevier]

Stomata are microscopic openings that allow for the exchange of gases between plants and the environment. In Arabidopsis , stomatal patterning is specified by the ERECTA family (ERf) receptor kinases (RKs), the receptor-like protein (RLP) TOO MANY MOUTHS (TMM), and EPIDERMAL PATTERNING FACTOR (EPF) peptides. Here we show that TMM and ER or ER-LIKE1 (ERL1) form constitutive complexes, which recognize EPF1 and EPF2, but the single ERfs do not. TMM interaction with ERL1 creates a binding pocket for recognition of EPF1 and EPF2, indicating that the constitutive TMM-ERf complexes function as the receptors of EPF1 and EPF2. EPFL9 competes with EPF1 and EPF2 for binding to the ERf-TMM complex. EPFL4 and EPFL6, however, are recognized by the single ERfs without the requirement of TMM. In contrast to EPF1,2, the interaction of EPFL4,6 with an ERf is greatly reduced in the presence of TMM. Taken together, our data demonstrate that TMM dictates the specificity of ERfs for the perception of different EPFs, thus functioning as a specificity switch for the regulation of the activities of ERfs., (© 2017 Lin et al.; Published by Cold Spring Harbor Laboratory Press.)

Valves on the plant epidermis called stomata develop according to positional cues, which likely involve putative ligands (EPIDERMAL PATTERNING FACTORS [EPFs]) and putative receptors (ERECTA family receptor kinases and TOO MANY MOUTHS [TMM]) in Arabidopsis. Here we report the direct, robust, and saturable binding of bioactive EPF peptides to the ERECTA family. In contrast, TMM exhibits negligible binding to EPF1 but binding to EPF2. The ERECTA family forms receptor homomers in vivo. On the other hand, TMM associates with the ERECTA family but not with itself. While ERECTA family receptor kinases exhibit complex redundancy, blocking ERECTA and ERECTA-LIKE1 (ERL1) signaling confers specific insensitivity to EPF2 and EPF1, respectively. Our results place the ERECTA family as the primary receptors for EPFs with TMM as a signal modulator and establish EPF2-ERECTA and EPF1-ERL1 as ligand-receptor pairs specifying two steps of stomatal development: initiation and spacing divisions. [ABSTRACT FROM AUTHOR]

One of the main challenges to the research on allelopathy is technically the separation of allelopathic effect from competition, and quantitatively, the assessment of the contribution of each component to overall interference. A simple mathematical model is proposed to calculate the contribution of allelopathy and competition to interference. As an example of applying the quantitative model to interference by barley (Hordeum vulgare cv. Triumph), the approach used was an addition of allelopathic effect, by an equivalent amount, to the environment of the test plant (white mustard, Sinapis alba), rather than elimination of competition. Experiments were conducted in glasshouse to determine the magnitude of the contributions of allelopathy and competition to interference by barley. The leachates of living barley roots significantly reduced the total dry weight of white mustard. The model involved the calculation of adjusted densities to an equivalent basis for modelling the contribution of allelopathy and competition to total interference. The results showed that allelopathy contributed 40%, 37% and 43% to interference by barley at 6, 12 and 18 white mustard pot(-1). The consistency in magnitude of the calculated contribution of allelopathic effect by barley across various densities of receiver plant suggested that the adjusted equivalent density is effective and that the model is able to assess the contribution of each component of interference regardless of the density of receiver plant.