What's in my Pot? Six Colletotrichum Species Causing Anthracnose in Brazilian Pecan Orchards

Pecan (Carya illinoinensis) is one important exotic forest crop cultivated in South America, specifically in Brazil, Uruguay, and Argentina. However, diseases such as anthracnose, favored by high humidity conditions and high summer temperatures, make its cultivation difficult, causing important loss to pecan farmers. This study used morphological and molecular approaches to identify the Colletotrichum species causing anthracnose in pecan plantations in Southern Brazil. The isolates obtained from pecan fruits with anthracnose symptoms were grouped through quantitative morphological characteristics into three distinct morphotypes. Molecular analysis of nuclear genes allowed the identification of six species of Colletotrichum causing anthracnose in pecan: C. nymphaeae, C. fioriniae, C. gloeosporioides, C. siamense, C. kahawae, and C. karsti. Three of these species are reported for the first time as causal agents of anthracnose in pecan. Therefore, these results provide an important basis for the adoption and/or development of anthracnose management strategies in pecan orchards cultivated in southern Brazil and neighboring countries.

https://doi.org/10.1007/s00284-024-03622-y

 

 


A haplotype-resolved chromosome-level assembly and annotation of European hazelnut (C. avellana cv. Jefferson) provides insight into mechanisms of eastern filbert blight resistance

European hazelnut (Corylus avellana L.) is an important tree nut crop. Hazelnut production in North America is currently limited in scalability due to Anisogramma anomala, a fungal pathogen that causes Eastern Filbert Blight (EFB) disease in hazelnut. Successful deployment of EFB resistant cultivars has been limited to the state of Oregon, where the breeding program at Oregon State University (OSU) has released cultivars with a dominant allele at a single resistance locus identified by classical breeding, linkage mapping, and molecular markers. 'Jefferson' is resistant to the predominant EFB biotype in Oregon and has been selected by the OSU breeding program as a model for hazelnut genetic and genomic research. Here, we present a near complete, haplotype-resolved chromosome-level hazelnut genome assembly for C. avellana 'Jefferson'. This new assembly is a significant improvement over a previously published genome draft. Analysis of genomic regions linked to EFB resistance and self-incompatibility confirmed haplotype splitting and identified new gene candidates that are essential for downstream molecular marker development, thereby facilitating breeding efforts.
https://doi.org/10.1093/g3journal/jkae021

 

 


Development of green composites from bio‐benzoxazine and epoxy copolymer reinforced with alkali‐treated pine nut shell particles

In the current study, an isothermal compression molding process was used to develop enhanced green composites made from alkali-treated pine nut shell particles (TPS) reinforced in fully bio-driven benzoxazine (VB) and epoxy (EP) copolymer. Reinforcement with varying weight percent (wt%) of bio-filler enhanced the properties of composites. Composites showed a rise of 75.9 MPa, 5.8 GPa, and 5.1 kJ/m2 in flexural strength, modulus, and impact strength, respectively. Thermal stability shows that composites can endure higher temperatures and hence be classified as flame-retardant materials. The dynamic mechanical analysis (DMA) confirms that composites exhibit higher storage modulus, which was elevated to 77.6% compared to the unfilled copolymer. FTIR spectroscopy analyzed the structure of copolymerized composites. Further, finite element analysis (FEA) was observed for the prepared composites. A transversely isotropic composite material model was created with the properties of composites, and stress analysis was observed. FEA outcomes are in good agreement with experimental findings.
https://doi.org/10.1002/pat.6245


Rheological Characteristics of Wheat Dough Containing Powdered Hazelnuts or Walnuts Oil Cakes

This study assessed edible oil industry byproducts, oil cakes (OC) based on hazelnuts and walnuts (HOC, WOC), to replace wheat flour dough (WD) based on farinograph and extensograph parameters and rheological measurements. The research hypothesis of this work is that replacing part of wheat flour with ground nut oil cakes modifies the rheological characteristics of the dough. WF was replaced at the level of 5%, 10% and 15%. It was shown that use of OC in flour mixtures at various levels significantly influenced the rheological properties of the dough. The water absorption of wheat flour and oil cake mixtures was higher than that of the control sample, and the average value of this indicator was 53.4%. The control sample had the lowest dough development time (DDT), and the presence of HOC or WOC in the system resulted in a significant increase in this parameter (p < 0.05). The average DDT of WDHOC cakes was 4.7 min and was lower compared to WDWOC which was 5.9 min. The WDWOC10% and WDWOC15% samples were characterized by the highest dough stability value and the lowest degree of softening (p < 0.05). The presence of OC in the flour mixtures increased the values of the storage and loss moduli, which was reflected in the K′ and K″ values. The values of these parameters also increased as the level of OC addition increased. WDHOC doughs were characterized by higher values of the K′ and K″ parameters compared to WDWOC. The results of the creep and recovery test showed that the dough with the addition of nut OC was less susceptible to deformation compared to the control dough (p < 0.05). The resistance to deformation increased with the increasing share of HOC or WOC in the mixtures. The average value of viscoelastic compliance (J1) of this parameter for WDHOC dough was on average 1.8 × 10−4 Pa−1, and for WDWOC 2.0 × 10−4 Pa−1. Nut oil cakes are an interesting technological addition to the dough. Their use may have a positive impact on the characteristics of the finished product and expand their application possibilities in the food industry. This is because the dough with the addition of nut cakes was more stiff and less flexible and susceptible to deformation.

https://doi.org/10.3390/foods13010140


Breakthrough curve analysis of phosphorylated hazelnut shell waste in column operation for continuous harvesting of lithium from water

In batch-scale operations, biosorption employing phosphorylated hazelnut shell waste (FHS) revealed excellent lithium removal and recovery efficiency. Scaling up and implementing packed bed column systems necessitates further design and performance optimization. Lithium biosorption via FHS was investigated utilizing a continuous-flow packed-bed column operated under various flow rates and bed heights to remove Li to ultra-low levels and recover it. The Li biosorption capacity of the FHS column was unaffected by the bed height, however, when the flow rate was increased, the capacity of the FHS column decreased. The breakthrough time, exhaustion time, and uptake capacity of the column bed increased with increasing column bed height, whereas they decreased with increasing influent flow rate. At flow rates of 0.25, 0.5, and 1.0 mL/min, bed volumes (BVs, mL solution/mL biosorbent) at the breakthrough point were found to be 477, 369, and 347, respectively, with the required BVs for total saturation point of 941, 911, and 829, while the total capacity was calculated as 22.29, 20.07, and 17.69 mg Li/g sorbent. In the 1.0, 1.5, and 2.0 cm height columns filled with FHS, the breakthrough times were 282, 366, and 433 min, respectively, whereas the periods required for saturation were 781, 897, and 1033 min. The three conventional breakthrough models of the Thomas, Yoon-Nelson, and Modified Dose-Response (MDR) were used to properly estimate the whole breakthrough behavior of the FHS column and the characteristic model parameters. Li's extremely favorable separation utilizing FHS was evidenced by the steep S-shape of the breakthrough curves for both parameters flow rate and bed height. The reusability of FHS was demonstrated by operating the packed bed column in multi-cycle mode, with no appreciable loss in column performance. https://doi.org/10.1016/j.chroma.2023.464510


Cashew Nutshells: A Promising Filler for 3D Printing Filaments

Cashew nutshells from the northern region of Colombia were prepared to assess their potential use as a filler in polymer matrix filaments for 3D printing. After drying and grinding processes, cashew nutshells were characterized using scanning electron microscopy (SEM), attenuated total reflectance Fourier-transform infrared (ATR-FTIR), and thermogravimetric analyses (TGA). Three different filaments were fabricated from polylactic acid pellets and cashew nutshell particles at 0.5, 1.0, and 2.0 weight percentages using a single-screw extruder. Subsequently, single-filament tensile tests were carried out on them. SEM images showed rough and porous particles composed of an arrangement of cellulose microfibrils embedded in a hemicellulose and lignin matrix, the typical microstructure reported for natural fibers. These characteristics observed in the particles are favorable for improving filler-matrix adhesion in polymer matrix composites. In addition, their low density of 0.337 g/cm3 makes them attractive for lightweight applications. ATR-FTIR spectra exhibited specific functional groups attributed to hemicellulose, cellulose, and lignin, as well as a possible transformation to crystalline cellulose during drying treatment. According to TGA analyses, the thermal stability of cashew nutshell particles is around 320 °C. The three polylactic acid-cashew nutshell particle filaments prepared in this work showed higher tensile strength and elongation at break when compared to polylactic acid filament. The characteristics displayed by these cashew nutshell particles make them a promising filler for 3D printing filaments. https://doi.org/10.3390/polym15224347


Characterization of Artificial Stone Produced with Blast Furnace Dust Waste Incorporated into a Mixture of Epoxy Resin and Cashew Nut Shell Oil

The demand for materials with improved properties and less negative impact on the environment is growing. Artificial stones are examples of these materials produced with up to 90% of particulate material joined by a binder. This article evaluates the physical and mechanical properties of two artificial stones produced with processing steel residue (blast furnace dust waste) and quartz powder. Two binders were used: pure epoxy resin, denoted as ASPB100, or a mixture of 70 wt% epoxy resin with 30 wt% cashew nut shell oil, denoted as ASPB7030. The process took place under vibration, compression (3 MPa/20 min and 90 °C) and vacuum (80 Pa). ASPB100 showed water absorption of 0.07%, while for ASPB7030, it was 0.54%. They were classified as having high mechanical strength associated with bending stress values equal to 32 and 25 MPa, respectively. Stain resistance indicated that both artificial stones had their stains removed with the tested cleaning agents. In this way, the novel artificial stones produced are sustainable alternatives for the application of blast furnace waste and cashew nut shell oil, reducing their negative impacts on the environment. https://doi.org/10.3390/polym15204181


Valorization of walnut green husk (Juglans regia L.) through sequential electrohydrodynamic extraction of pectin and phenolics: Process optimization and multidimensional analysis

This study aimed to optimize the extraction of pectin and phenolics from walnut green husk using the electrohydrodynamic method (EHD) and assess its impact on the chemical structure and properties of pectin. A comparative analysis was conducted with acidified water as the conventional extraction method. The results revealed significant improvements under the optimal EHD conditions (36.8 min, 17.5 kV, 90 °C), leading to a remarkable increase of over 64 % in pectin yield and >20 % in total phenolic content in half the extraction time. Chemical analysis showed that pectin samples contain 1.4-1.7 % ash, 3.6-4.6 % protein, over 90 % carbohydrates, and a galacturonic acid content ranging from 67.7 to 68.2 g/g. Both extraction methods yielded pectin with a high methoxyl degree, comparable thermal stability, and amorphous structure. EHD treatment resulted in reduced molecular weight, degree of esterification, water-holding capacity, and emulsion stability of pectin while enhancing its solubility and emulsion capacity. In summary, EHD treatment significantly improved extraction yield and changed the functionality of pectin, particularly in terms of emulsion activity. This alteration should be considered when utilizing pectin for specific applications. https://doi.org/10.1016/j.ijbiomac.2023.127545


Effects of walnut seed coat polyphenols on walnut protein hydrolysates: Structural alterations, hydrolysis efficiency, and acetylcholinesterase inhibitory capacity

The walnut meal is rich in nutrients such as protein from the kernel and polyphenolic compounds from the seed coat. However, the influences of seed coat polyphenols on walnut protein (WP) hydrolysis remained unclear. In this study, our findings indicated that polyphenols induced alterations in the secondary structure and amino acid composition of WP. These changes resulted in both a hindrance of hydrolysis and an enhancement of acetylcholinesterase (AChE) inhibition. Furthermore, four peptides of 119 identified peptides (LR, SF, FQ, and FR) were synthesized based on higher predicted bioactivity and Vinascores in silico. Among them, FQ showed interaction with amino acid residues in AChE through the formation of four π-π stacking bonds and two hydrogen bonds, resulting in the highest AChE inhibitory capacity. The combination index showed that chlorogenic acid derived from the seed coat and FQ at the molar ratio of 1:4 exhibited synergistic effects of AChE inhibition. https://doi.org/10.1016/j.foodchem.2023.137905


Impact of Modified Atmosphere Packaging Conditions on Quality of Dates: Experimental Study and Predictive Analysis Using Artificial Neural Networks

Dates are highly perishable fruits, and maintaining their quality during storage is crucial. The current study aims to investigate the impact of storage conditions on the quality of dates (Khalas and Sukary cultivars) at the Tamer stage and predict their quality attributes during storage using artificial neural networks (ANN). The studied storage conditions were the modified atmosphere packing (MAP) gases (CO2, O2, and N), packaging materials, storage temperature, and storage time, and the evaluated quality attributes were moisture content, firmness, color parameters (L*, a*, b*, and ∆E), pH, water activity, total soluble solids, and microbial contamination. The findings demonstrated that the storage conditions significantly impacted (p < 0.05) the quality of the two stored date cultivars. The use of MAP with 20% CO2 + 80% N had a high potential to decrease the rate of color transformation and microbial growth of dates stored at 4 °C for both stored date cultivars. The developed ANN models efficiently predicted the quality changes of stored dates closely aligned with observed values under the different storage conditions, as evidenced by low Root Mean Square Error (RMSE) and Mean Absolute Percentage Error (MAPE) values. In addition, the reliability of the developed ANN models was further affirmed by the linear regression between predicted and measured values, which closely follow the 1:1 line, with R2 values ranging from 0.766 to 0.980, the ANN models demonstrate accurate estimating of fruit quality attributes. The study's findings contribute to food quality and supply chain management through the identification of optimal storage conditions and predicting the fruit quality during storage under different atmosphere conditions, thereby minimizing food waste and enhancing food safety.
https://doi.org/10.3390/foods12203811