Observed improvements in animal and sward performance, coupled with a desire for more sustainable pasture-based feeding systems has triggered a surge in the implementation of more botanically diverse pastures. However, thus far, there has been limited research investigating the effects of botanically diverse sward types on enteric methane (CH4) or nitrogen (N) excretion, alongside the ruminal microbiota and fermentation profile, in sheep. Hence, this study investigates the effect of sward type on CH4 production and N excretion, in addition to assessing the rumen microbiome, volatile fatty acid (VFA) proportions, and ammonia nitrogen (NH3-N) concentration in sheep. A 5×5 Latin square design experiment was implemented to investigate five dietary treatments; perennial ryegrass (Lolium perenne L.;PRG) only or PRG plus white clover (Trifolium repens L.;PRG+WC), red clover (Trifolium pratense L.;PRG+RC), chicory (Chicorium intybus L.;PRG+Chic) or plantain (Plantago lanceolata L.;PRG+Plan). Diets were mixed at a ratio of 75% PRG and 25% of the respective companion forage and 100% PRG for the PRG treatment, on a dry matter basis. Twenty castrated male sheep were housed in metabolism crates across five feeding periods. Methane measurements were acquired utilizing portable accumulation chambers. Rumen fluid was harvested using a transoesophageal sampling device. Microbial rumen DNA was extracted and subjected to 16S rRNA amplicon sequencing and fermentation analysis. Data were analysed using PROC MIXED in SAS. Results show that animals consuming PRG+WC ranked lower for CH4 production (g/d) than sheep offered PRG, PRG+Chic or PRG+Plan (P<0.01) while the addition of any companion forage ranked CH4 yield (g/kg DMI) lower (P<0.001) than PRG. There was a moderate positive correlation between DMI and CH4 (g/d; r=0.51). Ruminal NH3-N was lowest in animals consuming the PRG diet (P<0.01). There was a greater abundance of Methanobrevibacter and reduced abundance of Methanosphaera (P<0.001) in sheep offered PRG, compared with any binary sward. On average, herb diets (PRG+Chic or PRG+Plan) reduced urinary nitrogen concentration of sheep by 34% in comparison to legume diets (PRG+WC or PRG+RC) and 13% relative to the PRG diet (P<0.001). Sheep offered PRG+Chic had a greater dietary nitrogen use efficiency than PRG+RC (P<0.05). This study demonstrates the potential for sward type to influence rumen function and the microbial community, along with CH4 and N output from sheep.

In this study, three beverages formulated with quinoa and chickpea flour blends were fermented using Lactobacillus acidophilus LA-5 to assess the effect of lactic acid fermentation on the degree of hydrolysis of plant-based proteins. Additionally, the impact of quinoa and chickpea blends on the protein content and protein solubility in the beverages was evaluated. Fermentation was completed within 10 h, resulting in a decrease in the pH (<4.3) and an increase in titratable acidity and lactic acid (>0.37 % and > 1.7 g/L), respectively. SDS-PAGE and the O-phthalaldehyde method revealed hydrolysis of quinoa and chickpea proteins. A quinoa-to-chickpea ratio of 50 % exhibited the highest protein content (>2 %), solubility (43.6 %), and hydrolysis (35.9 %) after fermentation, indicating that an increase in chickpea improved these parameters in the prepared PBBs. Overall, fermentation using Lactobacillus acidophilus increased plant protein hydrolysis, and legume addition improved the protein content and the nutritional value of plant-based beverages.

Root exudates are known signaling agents that influence legume root nodulation, but the molecular mechanisms for nonflavonoid molecules remain largely unexplored. The number of soybean root nodules during the initial growth phase shows substantial discrepancies at distinct developmental junctures. Using a combination of metabolomics analyses on root exudates and nodulation experiments, we identify a pivotal role for certain root exudates during the rapid growth phase in promoting nodulation. Phenoxyacetic acid (POA) was found to activate the expression of GmGA2ox10 and thereby facilitate rhizobial infection and the formation of infection threads. Furthermore, POA exerts regulatory control on the miR172c-NNC1 module to foster nodule primordia development and consequently increase nodule numbers. These findings collectively highlight the important role of POA in enhancing nodulation during the accelerated growth phase of soybeans.

Rhizobia interact with leguminous plants in the soil to form nitrogen fixing nodules in which rhizobia and plant cells coexist. Although there are emerging studies on rhizobium-associated nitrogen fixation in cereals, the legume-rhizobium interaction is more well-studied and usually serves as the model to study rhizobium-mediated nitrogen fixation in plants. Rhizobia play a crucial role in the nitrogen cycle in many ecosystems. However, rhizobia are highly sensitive to variations in soil conditions and physicochemical properties (i.e. moisture, temperature, salinity, pH, and oxygen availability). Such variations directly caused by global climate change are challenging the adaptive capabilities of rhizobia in both natural and agricultural environments. Although a few studies have identified rhizobial genes that confer adaptation to different environmental conditions, the genetic basis of rhizobial stress tolerance remains poorly understood. In this review, we highlight the importance of improving the survival of rhizobia in soil to enhance their symbiosis with plants, which can increase crop yields and facilitate the establishment of sustainable agricultural systems. To achieve this goal, we summarize the key challenges imposed by global climate change on rhizobium-plant symbiosis and collate current knowledge of stress tolerance-related genes and pathways in rhizobia. And finally, we present the latest genetic engineering approaches, such as synthetic biology, implemented to improve the adaptability of rhizobia to changing environmental conditions.

Metabolite profiling is an analytical technique used to assess metabolites in complex biological samples. This technique allows for the identification of both targeted and untargeted metabolites. In this study, the effect of traditional (fermentation and malting) and novel processing (ultrasonication) on the metabolites of finger millet (FM) and Bambara groundnut (BGN) flour was investigated using gas chromatography-mass spectrometry. Various metabolite classes, including amino acids, alcohol, aldehyde, organic acid, ester, fatty acids, glycoside, and sugar, were identified in FM and BGN flours. The adopted processing techniques impacted metabolite composition, as evidenced by substantial variations in volatile compound levels and metabolite composition among the FM and BGN samples before and after traditional and novel processing. Important health-promoting compounds, such as oleic acid, linoelaidic acid, and linoleic acid, were identified at their highest levels in fermented FM and BGN flours. The results obtained from this study offer an important context for monitoring and regulating the metabolite composition of FM and BGN flours under traditional and novel processing. PRACTICAL APPLICATION: Fermentation, malting, and ultrasonication induced desirable changes in some health-promoting compounds of finger millet and Bambara groundnut flours. The food and pharmaceutical industries could benefit from these traditional- and novel-modified flours as they could be used as improved food sources with health benefits.

Lentils are marketed as dry seeds, fresh sprouts, flours, protein isolates, and concentrates used as ingredients in many traditional and innovative food products, including dairy and meat analogs. Appreciated for their nutritional and health benefits, lentil ingredients and food products may be affected by off-flavor notes described as \"beany\", \"green\", and \"grassy\", which can limit consumer acceptance. This narrative review delves into the volatile profiles of lentil ingredients and possible de-flavoring strategies, focusing on their effectiveness. Assuming that appropriate storage and processing are conducted, so as to prevent or limit undesired oxidative phenomena, several treatments are available: thermal (pre-cooking, roasting, and drying), non-thermal (high-pressure processing, alcohol washing, pH variation, and addition of adsorbents), and biotechnological (germination and fermentation), all of which are able to reduce the beany flavor. It appears that lentil is less studied than other legumes and more research should be conducted. Innovative technologies with great potential, such as high-pressure processing or the use of adsorbents, have been not been explored in detail or are still totally unexplored for lentil. In parallel, the development of lentil varieties with a low LOX and lipid content, as is currently in progress for soybean and pea, would significantly reduce off-flavor notes.

Rhizobial attachment to host legume roots is the first physical interaction of bacteria and plants in symbiotic nitrogen fixation. The pH-dependent primary attachment of Rhizobium leguminosarum biovar viciae 3841 to Pisum sativum (pea) roots was investigated by genome-wide insertion sequencing, luminescence-based attachment assays, and proteomic analysis. Under acid, neutral, or alkaline pH, a total of 115 genes are needed for primary attachment under one or more environmental pH, with 22 genes required for all. These include components of cell surfaces and membranes, together with enzymes that construct and modify them. Mechanisms of dealing with stress also play a part; however, exact requirements vary depending on environmental pH. RNASeq showed that knocking out the two transcriptional regulators required for attachment causes massive changes in the bacterial cell surface. Approximately half of the 54 proteins required for attachment at pH 7.0 have a role in the later stages of nodule formation. We found no evidence for a single rhicadhesin responsible for alkaline attachment, although sonicated cell surface fractions inhibited root attachment at alkaline pH. Our results demonstrate the complexity of primary root attachment and illustrate the diversity of mechanisms involved.
OBJECTIVE: The first step by which bacteria interact with plant roots is by attachment. In this study, we use a combination of insertion sequencing and biochemical analysis to determine how bacteria attach to pea roots and how this is influenced by pH. We identify several key adhesins, which are molecules that enable bacteria to stick to roots. This includes a novel filamentous hemagglutinin which is needed at all pHs for attachment. Overall, 115 proteins are required for attachment at one or more pHs.

Acrylamide is a well-recognized hazardous compound with known carcinogenic, genotoxic, neurotoxic, and reproductive toxic effects. This research aimed to investigate how different legume species and roasting durations influence acrylamide formation during air-fryer roasting. The study also examined the relationship between acrylamide formation and the levels of free asparagine and free sugars in different bean species. Asparagine content varies substantially across different bean species. Sucrose was the predominant sugar across all bean species, with smaller amounts of galactose and glucose. Air-fryer-roasted Wandu kong (garden pea) showed the highest acrylamide formation, followed by Ultari kong (kidney bean) and Heoktae (black soybean), in that order. Beans roasted for longer periods in an air fryer contained significantly higher levels of acrylamide. This study revealed a strong positive correlation between acrylamide formation and the level of free asparagine in the beans, highlighting the risks associated with certain legume species and air-fryer roasting durations.

Legumes perform symbiotic nitrogen fixation through rhizobial bacteroids housed in specialised root nodules. The biochemical process is energy-intensive and consumes a huge carbon source to generate sufficient reducing power. To maintain the symbiosis, malate is supplied by legume nodules to bacteroids as their major carbon and energy source in return for ammonium ions and nitrogenous compounds. To sustain the carbon supply to bacteroids, nodule cells undergo drastic reorganisation of carbon metabolism. Here, a comprehensive quantitative comparison of the mitochondrial proteomes between root nodules and uninoculated roots was performed using data-independent acquisition proteomics, revealing the modulations in nodule mitochondrial proteins and pathways in response to carbon reallocation. Corroborated our findings with that from the literature, we believe nodules preferably allocate cytosolic phosphoenolpyruvates towards malate synthesis in lieu of pyruvate synthesis, and nodule mitochondria prefer malate over pyruvate as the primary source of NADH for ATP production. Moreover, the differential regulation of respiratory chain-associated proteins suggests that nodule mitochondria could enhance the efficiencies of complexes I and IV for ATP synthesis. This study highlighted a quantitative proteomic view of the mitochondrial adaptation in soybean nodules.

Trichoderma spp. is known for its ability to enhance plant growth and suppress disease, but the mechanisms for its interaction with host plants and pathogens remain unclear. This study investigated the transcriptomics and metabolomics of peanut plants (Arachis hypogaea L.) inoculated with Trichoderma harzianum QT20045, in the absence and presence of the stem rot pathogen Sclerotium rolfsii JN3011. Under the condition without pathogen stress, the peanut seedlings inoculated with QT20045 showed improved root length and plant weight, increased indole acetic acid (IAA) production, and reduced ethylene level, with more active 1-aminocyclopropane-1-carboxylate acid (ACC) synthase (ACS) and ACC oxidase (ACO), compared with the non-inoculated control. Under the pathogen stress, the biocontrol efficacy of QT20045 against S. rolfsii was 78.51%, with a similar effect on plant growth, and IAA and ethylene metabolisms to the condition with no biotic stress. Transcriptomic analysis of peanut root revealed that Trichoderma inoculation upregulated the expression of certain genes in the IAA family but downregulated the genes in the ACO family (AhACO1 and AhACO) and ACS family (AhACS3 and AhACS1) consistently in the absence and presence of pathogens. During pathogen stress, QT20045 inoculation leads to the downregulation of the genes in the pectinesterase family to keep the host plant\'s cell wall stable, along with upregulation of the AhSUMM2 gene to activate plant defense responses. In vitro antagonistic test confirmed that QT20045 suppressed S. rolfsii growth through mechanisms of mycelial entanglement, papillary protrusions, and decomposition. Our findings highlight that Trichoderma inoculation is a promising tool for sustainable agriculture, offering multiple benefits from pathogen control to enhanced plant growth and soil health.