Beneficial effects of premeal almond load on glucose profile on oral glucose tolerance and continuous glucose monitoring: randomized crossover trials in Asian Indians with prediabetes
Background: Rapid conversion from prediabetes to diabetes and frequent postprandial hyperglycemia (PPHG) is seen in Asian Indians. These should be the target of dietary strategies. Objectives: We hypothesized that dietary intervention of preloading major meals with almonds in participants with prediabetes will decrease overall glycemia and PPHG. Design: The study included two phases: (1) an oral glucose tolerance test (OGTT)-based crossover randomized control study, the effect of a single premeal almond load (20 g) given before OGTT was evaluated (n = 60, 30 each period). (2) The continuous glucose monitoring system (CGMS)-based study for 3 days including premeal almond load before three major meals was a free-living, open-labeled, crossover randomized control trial, where control and premeal almond load diets were compared for glycaemic control (n = 60, 30 in each period). The study was registered at clinicaltrials.gov (registration no. NCT04769726). Results: In the OGTT-based study phase, the overall AUC for blood glucose, serum insulin, C-peptide, and plasma glucagon post-75 g oral glucose load was significantly lower for treatment vs. control diet (p < 0.001). Specifically, with the former diet, PPHG was significantly lower (18.05% in AUC on OGTT, 24.8% at 1-h, 28.9% at 2-h post OGTT, and 10.07% during CGMS). The CGMS data showed that premeal almond load significantly improved 24-glucose variability; SD of mean glucose concentration and mean of daily differences. Daily glycaemic control improved significantly as per the following: mean 24-h blood glucose concentration (M), time spent above 7.8 mmol/L of blood glucose, together with the corresponding AUC values. Premeal almond load significantly decreased following: overall hyperglycemia (glucose AUC), PPHG, peak 24-h glycaemia, and minimum glucose level during night. Conclusion: Incorporation of 20 g of almonds, 30 min before each major meal led to a significant decrease in PPHG (as revealed in OGTT-based study phase) and also improved insulin, C-peptide, glucagon levels, and improved glucose variability and glycemic parameters on CGMS in participants with prediabetes. https://doi.org/10.1038/s41430-023-01263-1
Lipid Oxidation and Volatile Compounds of Almonds as Affected by Gaseous Chlorine Dioxide Treatment to Reduce Salmonella Populations.
The effects of gaseous chlorine dioxide (ClO2) treatment, applied to inactivate Salmonella, on lipid oxidation, volatile compounds, and chlorate levels of dehulled almonds were evaluated during a 3 month accelerated storage at 39 °C. At treatment levels that yielded a 2.91 log reduction of Salmonella, ClO2 promoted lipid oxidation as indicated by increased peroxide values, total acid number, conjugated dienes, and thiobarbituric acid-reactive substances. Furthermore, several chlorine-containing volatile compounds including trichloromethane, 1-chloro-2-propanol, 1,1,1-trichloro-2-propanol, and 1,3-dichloro-2-propanol were identified in ClO2-treated samples. However, all the volatile chlorine-containing compounds decreased during the 3 months of storage. Chlorate (26.4 ± 5.1 μg/g) was found on the ClO2-treated samples. The amounts of non-ethanol alcohols, aldehydes, and carboxylic acids increased following ClO2 treatments. Some volatiles such as 2,3-butanediol that were present in non-treated samples became non-detectable during post-ClO2 treatment storage. Overall, our results demonstrated that gaseous ClO2 treatment promoted lipid oxidation, generation of volatiles of lipid origin, and several chlorine-containing compounds. https://doi.org/10.1021/acs.jafc.3c00267
Influence of Geographical Orchard Location on the Microbiome from the Progeny of a Pecan Controlled Cross.
Carya illinoinensis (Wangenh.) K.Koch production has expanded beyond the native distribution as the genetic diversity of the species, in part, has allowed the trees to grow under broad geographic and climatic ranges. Research in other plant species has demonstrated that the phytobiome enhances their ability to survive and thrive in specific environments and, conversely, is influenced by the prevailing environment and plant genetics, among other factors. We sought to analyze the microbiota of pecan seedlings from the controlled cross 'Lakota' × 'Oaxaca' that were made in Georgia and Texas, respectively, to determine if the maternal geographical origin influences the microbiome of the resulting progeny. No significant differences in bacterial communities were observed between the seeds obtained from the two different states (p = 0.081). However, seed origin did induce significant differences in leaf fungal composition (p = 0.012). Results suggest that, in addition to some environmental, epigenetics, or host genetic components, ecological processes, such as dispersal mechanisms of the host, differentially impact the pecan microbiome, which may have ramifications for the health of trees grown in different environments. Future studies on the role of the microbiome in plant health and productivity will aid in the development of sustainable agriculture for improved food security. https://doi.org/10.3390/plants12020360
The multifaceted roles of Arbuscular Mycorrhizal Fungi in peanut responses to salt, drought, and cold stress.
Background: Arbuscular Mycorrhizal Fungi (AMF) are beneficial microorganisms in soil-plant interactions; however, the underlying mechanisms regarding their roles in legumes environmental stress remain elusive. Present trials were undertaken to study the effect of AMF on the ameliorating of salt, drought, and cold stress in peanut (Arachis hypogaea L.) plants. A new product of AMF combined with Rhizophagus irregularis SA, Rhizophagus clarus BEG142, Glomus lamellosum ON393, and Funneliformis mosseae BEG95 (1: 1: 1: 1, w/w/w/w) was inoculated with peanut and the physiological and metabolomic responses of the AMF-inoculated and non-inoculated peanut plants to salt, drought, and cold stress were comprehensively characterized, respectively. Results: AMF-inoculated plants exhibited higher plant growth, leaf relative water content (RWC), net photosynthetic rate, maximal photochemical efficiency of photosystem II (PSII) (Fv/Fm), activities of antioxidant enzymes, and K+: Na+ ratio while lower leaf relative electrolyte conductivity (REC), concentration of malondialdehyde (MDA), and the accumulation of reactive oxygen species (ROS) under stressful conditions. Moreover, the structures of chloroplast thylakoids and mitochondria in AMF-inoculated plants were less damaged by these stresses. Non-targeted metabolomics indicated that AMF altered numerous pathways associated with organic acids and amino acid metabolisms in peanut roots under both normal-growth and stressful conditions, which were further improved by the osmolytes accumulation data. Conclusion: This study provides a promising AMF product and demonstrates that this AMF combination could enhance peanut salt, drought, and cold stress tolerance through improving plant growth, protecting photosystem, enhancing antioxidant system, and regulating osmotic adjustment. https://doi.org/10.1186/s12870-023-04053-w
Alternaria alternata Causing Brown Spot Disease on Walnut in Xinjiang, China.
Walnut is one of the Xinjiang's characteristic dried fruits and the main source of income for farmers in walnut growing areas. In September 2019, Juglans regia leaves with brown spots were observed in a 10 hm2 orchard in Hotan area, the diseased leaf rate reached more than 25%. The leaf lesions were suborbicular to irregular, black-brown, 3 to 8 mm in diameter, with distinct dark borders. Colonies were isolated from 10 diseased leaves collected from two trees in the orchard. Leaf sections (4 × 4 mm) from diseased leaves were surface disinfested with 75% ethyl alcohol for 30 s and 2% NaClO for 3 min, washed with sterile water three times and then plated on potato dextrose agar (PDA) and incubated at 27℃ with a 12h/12h light/dark photoperiod for 4 days. A total of 7 fungal isolates were obtained by single-spore isolation. All the colonies were dark olivaceous on the PDA plates, with loose, cottony mycelium. On potato carrot agar (PCA), all fungal isolates produced conidial chains with numerous secondary chains. The conidia were ellipsoid or obpyriform with 0-3 longitudinal septa and 2-4 transverse septa, measuring 20.6 to 35.8 × 6.8 to 11.2 μm (25.5 ± 0.4 × 8.7 ± 0.2 μm, n=50). The morphological characteristics of the seven fungal isolates were consistent with the A. alternata descriptions of Simmons (2007). DNA was extracted from 50 mg of mycelia for the representative isolate HLP17-7. The internal transcribed spacer (ITS) region was PCR amplified using the universal primers ITS1 / ITS4 (White et al.1990), the partial coding sequence of endopolygalacturonase (endoPG) and the partial region of the histone 3 (H3) were amplified using primers PG2b / PG3 (Andrew et al. 2009) and H3-1a / H3-1b (Glass and Donaldson 1995) respectively. The products were sequenced and deposited in GenBank database under the accession numbers MW514319 [ITS], ON806938 endoPG, MW489301 [H3]. ITS, endoPG and H3 sequences had 99.81% (1/535 nt difference), 99.78% (1/448 nt difference) and 100% (0/417 nt difference) homology with homologous sequences of A. alternata strains (KP124306 [ITS], KP124006 [endoPG], MK085979 [H3]), respectively. During the early autumn, pathogenicity tests were carried out on the healthy mature leaves of seven-year-old Juglans regia plants in the field. Thirty leaves (five leaves per plant) were wounded with a sterile needle and then sprayed with a spore suspension prepared from 10-day-old PDA culture. Five wounded leaves per plant were sprayed with sterile water as control. All the treated leaves were covered with clear plastic bags for 3 days, and the experiment was replicated three times. On the 8th day after inoculation, brown spots appeared on the inoculated leaves, but no spots were observed in the control. Morphological observation and gene sequencing confirmed that the original fungal pathogen was re-isolated from the inoculated leaves. No colony was isolated from the control leaves. The pathogen causing the brown spot was identified as A. alternata based on morphological features and sequence analysis. A. alternata has been reported previously in Sichuan (Yang et al., 2017) causing brown spot in walnut. Xinjiang is dry with little rain and abundant sunshine, so there are few diseases on walnuts. However, the occurrence of brown spot disease has alarmed fruit farmers, walnuts are still at the risk of A. alternata infections even in dry environment with little rain. To our knowledge, this is the first report of A. alternata causing brown spot in walnut in Xinjiang, China. https://doi.org/10.1094/PDIS-07-22-1536-PDN
First report of Fusarium concentricum as a causal agent of Fusarium leaf blotch on pecan (Carya illinoinensis) in Southeast China.
The economically important nut crop pecan (Carya illinoinensis (Wangenh.) K. Koch) is seriously affected by increasing incidence of fungal disease worldwide (Xiao et al 2021). The top leaves of the pecan variety 'Pawnee' in the orchard of Zhejiang A&F University, Zhejiang, China were damaged by massive dark brown plaques in summer to autumn 2021. The causal agent was isolated from leaves with target plaques following the steps: sterilized with 70% alcohol (30 s × 2), rinsed with sterilized water (3 ×) before and after 5% sodium hypochlorite (30 s), excised the plaques, and placed on PDA medium at 28℃ in a dark incubator for 3-d. The mycelium on the edge of each colony was transferred to fresh SNA medium in dark for 2 weeks to induce conidia formation. A few conidia-germinated mycelia were transferredand inoculated on new plates containing fresh PDA medium to obtain the purified cultures. Koch's postulates were applied to validate the pathogenicity of the purified isolates. Non-woundedly healthy leaves (disinfected with 5% sodium hypochlorite) of 'Pawnee' seedlings were inoculated with 5 mm 7-d old purified cultures. Dark-brown spots appeared on the leaves 2 days post inoculation at 25℃. The spots became larger accompanied by partially cracking and slight deformation of inoculated leaves from day 2 to day 4, while the control leaves remained asymptomatic. A re-isolated strain ZJ-6 from these infected leaves was identified as the pathogenic isolate with the same symptom as the previous one. Morphologically, aerial mycelia of the pathogenic isolate ZJ-6 cashmere and white. The reverse of colony orange. The edge of the colony appeared gradually thinner, the aerial mycelia loose and flocky, and the matrix mycelium whitened. Hyphae were septate, translucent with smooth wall and 1.47-7.14 µm in width. Microconidia (n = 20) obovoid to fusoid, mainly with 0-septate, 4.45-7.78×4.79-16.25 µm. Macroconidia (n = 20) sickle, mainly with 3-5 septa, 5.56-10.28×56.67-114.54 µm. Simultaneous of monophialidic and polyphialidic conidiophores. Conidiophore width 1.47-3.68 µm, slightly smaller than vegetative hyphae. The morphological characteristics matched with previous descriptions of Fusarium species (Nirenberg and O'Donnell 1998; Wang et al 2013). The identity of ZJ-6 was confirmed by phylogenetic reconstruction using the concatenated sequences of the ATP citrate lyase (ACL1), Calmodulin (CaM), the internal transcribed spacer (ITS) rDNA region, ribosomal RNA gene (LSU), the largest subunit of DNA-dependent RNA polymerase II (RPB1), partial translation elongation factor-1 alpha (TEF) and β-Tubulin (TUB). To this end, the genomic DNA of ZJ-6 was extracted by the M5 hipermix-MF859 (Mei5 Biotechnology) and submitted to GenBank under the accession numbers OP933646, OP933647, OP925890, OP925889, OP933396, OP933648, and OP933397, respectively. The obtained sequences of ZJ-6 were used for nucleotide BLAST against thetandard databases, respectively, and the strains with sequence identification values above 98% were selected to construct multiple alignment for building a phylogenetic tree. This analyses allowed the identification of ZJ-6 as Fusarium concentricum Nirenberg & O'Donnell, a species with few reports that can cause serious damage to the fruits and branches of other hosts (Hasan et al 2020; Huda-Shakirah et al 2020; Wang et al 2013). This is the first report of pathogenic F. concentricum on pecan in Southeast China that caused no harvest of infected plants. https://doi.org/10.1094/PDIS-12-22-2810-PDN
Impedimetric nanoimmunosensor platform for aflatoxin B1 detection in peanuts.
This article developed a novel electrochemical immunosensor for the specific detection of aflatoxin B1 (AFB1). Amino-functionalized iron oxide nanoparticles (Fe3O4-NH2) were synthesized. Fe3O4-NH2 were chemically bound on self-assembly monolayers (SAMs) of mercaptobenzoic acid (MBA). Finally, polyclonal antibodies (pAb) were immobilized on Fe3O4-NH2-MBA. The sensor system was evaluated through atomic force microscopy (AFM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). A reduction in the anodic and cathodic peak currents was observed after the assembly of the sensor platform. The charge transfer resistance (Rct) was increased due to the electrically insulating bioconjugates. Then, the specific interaction between the sensor platform and AFB1 blocks the electron transfer of the [Fe(CN)6]3−/4− redox pair. The nanoimmunosensor showed a linear response range estimated from 0.5 to 30 μg/mL with a limit of detection (LOD) of 9.47 μg/mL and a limit of quantification (LOQ) of 28.72 μg/mL for AFB1 identification in a purified sample. In addition, a LOD of 3.79 μg/mL, a LOQ of 11.48 μg/mL, and a regression coefficient of 0.9891 were estimated for biodetection tests on peanut samples. The proposed immunosensor represents a simple alternative, successfully applied in detecting AFB1 in peanuts, and therefore, represents a valuable tool for ensuring food safety. https://doi.org/10.1002/btpr.3334
Smart orchard design improves crop pollination.
More sustainable and environmentally friendly agricultural practices, including ecological intensification, are needed to reduce biodiversity loss and environmental degradation. We evaluated the potential of ecological intensification through the enhancement of pollination services in an intensively managed and insect-pollinated crop, Macadamia integrifolia. We compared the effects and importance of agronomic practices that include agronomic input (i.e. irrigation and managed honeybees), orchard design requiring no external inputs (i.e. spatial orchard structure) and landscape factors in 10 South African macadamia orchards. In comparison to experimental pollinator exclusion, insect pollination increased the initial and final nut set by 304% and 23%, respectively. However, nut set was pollination limited as hand pollination further improved nut set. Flower visitation rates increased with the cover of semi-natural habitats in the surrounding landscape (1 km radius). This effect was outperforming the effect of the number of managed honeybee colonies, as agronomic practice. Initial nut set increased with orchard design and flower visitation rates. Perpendicular orientation of the planted macadamia rows towards the semi-natural habitats increased initial nut set more than threefold compared to parallel row orientation. The initial nut set was 80% higher at the edge to semi-natural habitats than in the orchard centre. In contrast, agronomic practices, such as irrigation, did not increase initial nut set. Final nut set depended on the preconditions of the initial nut set, additionally, high altitudes and the position in the centre of the orchard had positive effects. Synthesis and applications: Pollination services were prerequisites for high yields in macadamia and could be improved without further agronomic input. Especially, the orchard design, that is, spatial arrangement of tree rows and semi-natural habitats at local and landscape scales, was more important to boost insect pollination and the initial development of macadamia nuts than agronomic practices, such as high levels of irrigation. Considering the urgency to reduce the environmental impacts of agricultural production, we highlight the high potential of ecological intensification by a smart orchard design and the restoration and conservation of semi-natural habitats in the orchards and their surrounding landscape. https://doi.org/10.1111/1365-2664.14363
The EU sustainable food systems framework - potential for climate action.
The EU’s Farm to Fork strategy (F2F) marks the first time that the EU addresses food sustainability covering both production and consumption (ref. 1, p. 586). The flagship initiative under the F2F strategy is an entirely novel Framework for a Sustainable Food System (FSFS). The FSFS is being developed at a time where the war on Ukraine has resurfaced the debate on food security, in particular that the initiatives under the F2F will lead to a decrease in EU food production and export (ref. 2, p. 15) and increased world food insecurity (ref. 3, p. 11). On the other hand, Röös et al. (p. 14)4, Pörtner et al. (p. 470)5 and Schiavo et al. (p. 40)6 argue that food insecurity will rather be a consequence of an unsustainable food system that threatens long-term food production. They state that a shift to agroecological practices, as promoted in the F2F strategy, can provide food security if in conjunction with demand-side dietary change, also promoted in the F2F strategy. It is clear that EU citizens will be important in order to demonstrate public support for the F2F strategy in general, and for the FSFS in particular. However, the abstract nature of the new Framework for a Sustainable Food System, the FSFS, may pose difficulties for citizens to exert political pressure on the next European Commission, on Member State governments and on the European Parliament. To make the FSFS more tangible as to what it could contain, I will outline three concrete policy proposals that the new law could include: (1) foster enabling food environments; (2) introduce a new incentives regime for food producers; (3) recognise animal welfare in the definition of a sustainable food system. https://doi.org/10.1038/s44168-023-00034-9
The Impact of Nutshell Biochar on the Environment as an Alternative Fuel or as a Soil Amendment.
Walnut, pistachio, and peanut nutshells were treated by pyrolysis to biochar and analyzed for their possible usage as fuels or soil fertilizers. All the samples were pyrolyzed to five different temperatures, i.e., 250 °C, 300 °C, 350 °C, 450 °C, and 550 °C. Proximate and elemental analyses were carried out for all the samples, as well as calorific value and stoichiometric analysis. For sample usage as a soil amendment, phytotoxicity testing was performed and the content of phenolics, flavonoids, tannin, juglone, and antioxidant activity were determined. To characterize the chemical composition of walnut, pistachio, and peanut shells, lignin, cellulose, holocellulose, hemicellulose, and extractives were determined. As a result, it was found that walnut shells and pistachio shells are best pyrolyzed at the temperature of 300 °C and peanut shells at the temperature of 550 °C for their use as alternative fuels. The highest measured net calorific value was in pistachio shells, which were biochar pyrolyzed at 550 °C, of 31.35 MJ kg−1. On the other hand, walnut biochar pyrolyzed at 550 °C had the highest ash share of 10.12% wt. For their use as soil fertilizers, peanut shells were the most suitable when pyrolyzed at 300 °C, walnut shells at 300 and 350 °C, and pistachio shells at 350 °C. https://doi.org/10.3390/ma16052074