Cell Wall Fraction Research Articles

55 Investigating the Potential Benefits of an Immunostimulant (Mycobacterium Cell Wall Fraction) Treatment on Increased Pregnancy Success of Embryo Transfer Recipients

Abstract Modulating the vaginal and uterine microbiome through the use of immunostimulants has the potential to improve fertility in cattle. The object of this study was to evaluate the potential benefits of an immunostimulant, mycobacterium cell wall fraction (MCWF), to increase pregnancy success of embryo transfer (ET) recipients. The three main objectives of this study were: determining if injecting ET recipient cows with MCWF increased proportion of cows with a corpus luteum (CL) on ET day, identifying differences in CL volume and progesterone concentration at the time of ET, and determining if ET recipients that received MCWF have greater pregnancy rate. A total of 926 beef cows at eight different locations were enrolled in this study. Primiparous and multiparous cattle were enrolled in a 7-day CO-Synch + CIDR estrous synchronization protocol. During this protocol, cows received an injection of GnRH (100-μg) at CIDR (controlled internal drug release) insertion [d -9], a prostaglandin F2α injection (25 mg), and CIDR removal [d-2] followed by another injection of GnRH (100 μg; d 0) within 60-66 hours after CIDR removal. At each location at (d 0), cows were sorted based on BCS and days post-partum and randomly assigned to one of two treatments: 1) MCWF- a single intramuscular injection (5 mL) of MCWF at (d 0; Amplimune, NovaVive Inc.; n = 452) or 2) Control- a single intramuscular injection (5 mL) of saline (n = 474). Seven days after (d 7), cows were examined by ultrasonography to determine if a CL was present. Recipient cows that had a CL received ET with a frozen or fresh in vivo or in vitro produced embryo in the ipsilateral uterine horn to the CL, with embryo type and grade balanced between treatments. Blood samples were collected in one location (n = 98) for analysis of plasma concentration of progesterone on (d 7) ET day. Pregnancy diagnosis was then performed by ultrasonography between 30 and 90 days of gestation. Data were analyzed using the GLIMMIX and MIXED procedures of SAS. Cow BCS and days postpartum were similar (P > 0.10) between treatments (5.5 ± 0.6 and 103 ± 14 days, respectively). Recipient cow utilization rate was similar between treatments (P = 0.49; 81.2 ± 0.42%). At the time of ET MCWF had larger CL than Control cows (5,768.6 ± 133.7 and 5,408.0 ± 128.5 mm3, respectively, P = 0.03). and increased progesterone concentration (2.68 ± 0.17 and 2.18 ± 0.14 ng/mL, respectively, P = 0.01). However, pregnancy rate to ET was similar (P = 0.922) between treatments (60.9 and 61.3 ± 0.05% for Control and MCWF, respectively). In conclusion, treatment of ET recipient cows with MCWF increased CL volume and concentration of progesterone at the time of ET but failed to generate greater pregnancy rates.

Subcritical water extraction of Equisetum arvense biomass withdraws cell wall fractions that trigger plant immune responses and disease resistance

Plant cell walls are complex structures mainly made up of carbohydrate and phenolic polymers. In addition to their structural roles, cell walls function as external barriers against pathogens and are also reservoirs of glycan structures that can be perceived by plant receptors, activating Pattern-Triggered Immunity (PTI). Since these PTI-active glycans are usually released upon plant cell wall degradation, they are classified as Damage Associated Molecular Patterns (DAMPs). Identification of DAMPs imply their extraction from plant cell walls by using multistep methodologies and hazardous chemicals. Subcritical water extraction (SWE) has been shown to be an environmentally sustainable alternative and a simplified methodology for the generation of glycan-enriched fractions from different cell wall sources, since it only involves the use of water. Starting from Equisetum arvense cell walls, we have explored two different SWE sequential extractions (isothermal at 160 ºC and using a ramp of temperature from 100 to 160 ºC) to obtain glycans-enriched fractions, and we have compared them with those generated with a standard chemical-based wall extraction. We obtained SWE fractions enriched in pectins that triggered PTI hallmarks in Arabidopsis thaliana such as calcium influxes, reactive oxygen species production, phosphorylation of mitogen activated protein kinases and overexpression of immune-related genes. Notably, application of selected SWE fractions to pepper plants enhanced their disease resistance against the fungal pathogen Sclerotinia sclerotiorum. These data support the potential of SWE technology in extracting PTI-active fractions from plant cell wall biomass containing DAMPs and the use of SWE fractions in sustainable crop production.

Diet supplemented with Saccharomyces cerevisiae from different fermentation media modulates the faecal microbiota and the intestinal fermentative products in dogs.

This study aimed at evaluating the coefficients of total tract apparent digestibility (CTTAD) of nutrients, metabolisable energy (ME), diet palatability, faecal fermentative products and microbiota of dogs fed yeasts from different fermentation media and its fractions. Four diets were evaluated: control, without yeast (CO); diet with 10 g/kg brewer's yeast (BY); diet with 10 g/kg brewer's yeast + corn yeast (BCY); and diet with 10 g/kg BCY + cell wall fractions (BCYF). Twelve adult dogs were distributed in a randomized block design (periods). Each of the four diets was fed to a group of three dogs per period of 20 days, totalling two periods and six repetitions per treatment. Sixteen adult dogs were used for the palatability test, which compared the CO diet versus each one of the yeast diets. Data with normal distribution were subjected to analysis of variance (p < 0.05). Means were compared by orthogonal contrasts (p < 0.05): (A) CO diet versus BY, BCYand BCYF diets; (B) BY diet versus BCY and BCYF diets; (C) BCY diet versus BCYF diet. There was no difference in the CTTAD and ME of the diets (p > 0.05). Yeast diets reduced faecal odour and indole peak area (p < 0.05). Faecal short-chain fatty acids concentration was greater in dogs fed yeast diets compared to those fed the CO (p < 0.05). Yeast diets showed a higher intake ratio compared to the CO (p < 0.05). The BCY and BCYF diets resulted in a greater abundance of Bacteroides, Faecalibacterium, Coprococcus, and Phascolarctobacterium in relation to the CO (p < 0.05). Our results suggest that dietary yeast supplementation results in beneficial changes in intestinal functionality indicators, mainly with the combination of yeasts from brewers and corn fermentation media. In addition, yeast supplementation improves diet palatability without compromising nutrient digestibility.

138 Effect of administration of mycobacterium cell wall fraction during the peri-ovulatory period on embryo production following superovulation in virgin dairy heifers

138 Effect of administration of mycobacterium cell wall fraction during the peri-ovulatory period on embryo production following superovulation in virgin dairy heifers

67 Digestibility and glycemic response of timothy-based haylage and timothy grass hay

Haylage is often fed to horses around the world and may be an appealing forage choice for certain horses due to its low dust content and lower NSC content when compared with hay of comparable species and maturity. The objective of this study was to determine if there were differences in digestibility and glycemic response between hay and haylage of similar quality. Four Thoroughbred geldings (9.3 ± 1.5 yr; 617 ± 40 kg; mean ± SD) were used in a crossover design with 2 dietary treatments over 2 28-d periods. The 2 dietary treatments were second-cutting timothy hay and timothy-ryegrass haylage both fed at 1.5% BW (DM basis). To minimize refusals, one horse was fed at 1% BW (DM basis) for the last 9 d of each period. The hay contained 15% WSC, 0.7% starch, 35% ADF, and 57% NDF, and the haylage contained 9% WSC, 0.8% starch, 39% ADF, and 66% NDF (DM basis). The hay and haylage had similar lignification of the cell wall fraction (lignin/NDF; 9.1% vs 8.4%, respectively). Total fecal collections were conducted during the last 5 d of each period to determine digestibility. Glycemic response to a meal of the assigned forage was conducted on d 22of each period by analyzing plasma for glucose every 30 min for 480 min post-feeding and calculating the area under the curve (AUC). The effect of treatment was analyzed using an ANOVA (SAS Institute Inc., Cary NC) and significance was defined when P < 0.05. The AUC per g of NSC was not different between diets (P > 0.10). Horses had a slower rate of DM intake when fed the haylage meal (10 g DM/min versus 25 g DM/min for hay; P < 0.05) and also had a longer time to peak glucose (P < 0.05). Dry matter digestibility was 58.1% for hay and 50.4% for haylage (P < 0.05). Despite containing a similar degree of cell wall lignification, the hay diet resulted in a greater digestibility of NDF and ADF compared with the haylage diet (P < 0.05). Horses fed haylage had greater fecal moisture than horses fed hay (86% and 76%; P < 0.05) and demonstrated free fecal water. The appearance of free fecal water may have been related to the lower-than-expected fiber digestibility in the haylage diet. More research is needed to determine causative factors in the development of free fecal water in horses.

A novel approach for quantitative determination of cellulose content in tobacco via 2D HSQC NMR spectroscopy

Cellulose is an important component of tobacco (Nicotiana tabacum L.) cell walls, which can be precursors for many harmful compounds in smoke. Traditional cellulose content analysis methods involve sequential extraction and separation steps, which are time-consuming and environmentally unfriendly. In this study, a novel method was first introduced to analyze cellulose content in tobacco via two-dimensional heteronuclear single quantum coherence (2D HSQC) NMR spectroscopy. The method was based on derivatization approach to allow the dissolution of insoluble polysaccharide fractions of tobacco cell walls in DMSO‑d6/pyridine-d5 (4:1 v/v) for NMR analysis. The NMR results suggested that besides the main NMR signals of cellulose, partial signals of hemicellulose including mannopyranose, arabinofuranose, and galactopyranose units could also be identified. In addition, the utilization of relaxation reagents has proved to be an effective way to improve the sensitivity of 2D NMR spectroscopy, which was beneficial for quantification of biological samples with limited quantities. To overcome the limitations of quantification using 2D NMR, the calibration curve of cellulose with 1,3,5-trimethoxybenzene as internal reference was constructed and thus the accurate measurement of cellulose in tobacco was achieved. Compared with the chemical method, the interesting method was simple, reliable, and environmentally friendly, which provided a new insight for quantitative determination and structure analysis of plant macromolecules in complex samples.

Comparing cadmium uptake kinetics, xylem translocation, chemical forms, and subcellular distribution of two tobacco (Nicotiana tabacum L.) cultivars

Tobacco (Nicotiana tabacum L.) is a potential phytoremediator that can reduce soil cadmium (Cd) contamination. Pot and hydroponic experiments were conducted to investigate the difference in absorption kinetics, translocation patterns, accumulation capacity, and extraction amounts between two leading tobacco cultivars in China. We studied the chemical forms and subcellular distribution of Cd in the plants to understand the diversity of the detoxification mechanism of the cultivars. The concentration-dependent kinetics of Cd accumulation in leaves, stems, roots, and xylem sap for cultivars Zhongyan 100 (ZY100) and K326, fitted well with the Michaelis-Menten equation. K326 exhibited high biomass, Cd tolerance, Cd translocation, and phytoextraction abilities. The acetic acid, sodium chloride, and water-extractable fractions accounted for > 90% of Cd in all ZY100 tissues but only in K326 roots and stems. Moreover, the acetic acid and NaCl fractions were the predominant storage forms, while the water fraction was the transport form. The ethanol fraction also contributed significantly to Cd storage in K326 leaves. As the Cd treatment increased, more NaCl and water fractions were found in K326 leaves, while only NaCl fractions increased in ZY100 leaves. For subcellular distribution, > 93% Cd proportions were primarily stored in both cultivars' soluble or cell wall fraction. The proportion of Cd in the cell wall fraction of ZY100 roots was less than that of K326, while that proportion in the soluble fraction in ZY100 leaves was higher than in K326 leaves. These findings demonstrate that Cd accumulation patterns, detoxification, and storage strategies differ between the cultivars, providing a deeper understanding of Cd tolerance and accumulation mechanism in tobacco plants. It also guides the screening of germplasm resources or gene modification to improve the Cd phytoextraction efficiency of tobacco.

Genome and Transcriptome Identification of a Rice Germplasm with High Cadmium Uptake and Translocation.

The safe production of food on Cd-polluted land is an urgent problem to be solved in South China. Phytoremediation or cultivation of rice varieties with low Cd are the main strategies to solve this problem. Therefore, it is very important to clarify the regulatory mechanism of Cd accumulation in rice. Here, we identified a rice variety with an unknown genetic background, YSD, with high Cd accumulation in its roots and shoots. The Cd content in the grains and stalks were 4.1 and 2.8 times that of a commonly used japonica rice variety, ZH11, respectively. The Cd accumulation in the shoots and roots of YSD at the seedling stage was higher than that of ZH11, depending on sampling time, and the long-distance transport of Cd in the xylem sap was high. Subcellular component analysis showed that the shoots, the cell wall, organelles, and soluble fractions of YSD, showed higher Cd accumulation than ZH11, while in the roots, only the cell wall pectin showed higher Cd accumulation. Genome-wide resequencing revealed mutations in 22 genes involved in cell wall modification, synthesis, and metabolic pathways. Transcriptome analysis in Cd-treated plants showed that the expression of pectin methylesterase genes was up-regulated and the expression of pectin methylesterase inhibitor genes was down-regulated in YSD roots, but there were no significant changes in the genes related to Cd uptake, translocation, or vacuole sequestration. The yield and tiller number per plant did not differ significantly between YSD and ZH11, but the dry weight and plant height of YSD were significantly higher than that of ZH11. YSD provides an excellent germplasm for the exploration of Cd accumulation genes, and the cell wall modification genes with sequence- and expression-level variations provide potential targets for phytoremediation.

Physiological and biochemical response of P. fortunei to Mn exposure.

Fast-growing woody plants with metal tolerance are considered as potential candidates for phytoremediation. P. fortunei is widely distributed in China. Herein, the Mn tolerance ability and physiological and biochemical response of P. fortunei to Mn were explored in this study. Results showed that a low concentration of Mn exposure was favorable for the growth of P. fortunei, while it was inhibited in high Mn exposure. P. fortunei showed high tolerance to Mn (10mmol/L). The microstructure of P. fortunei organs revealed that the Mn tolerance of P. fortunei was related to the compartmentalization of the cell wall. The subcellular distribution of Mn in P. fortunei showed that Mn was mainly stored in the cell wall fraction (39%-90%). Under Mn exposure, the proportion of pectate and protein-integrated Mn increased by 5%-29% in P. fortunei. The changes of function groups (-CH3 and -COOH) in P. fortunei might be related to the reduction of Mn toxicity in plant cells in the way of chelation. Additionally, P. fortunei leaves resisted Mn toxicity by increasing the activities of CAT and SOD under low Mn concentration exposure, but it might be destroyed under excessive Mn concentration exposure. P. fortunei might be used as a candidate plant for low concentration Mn tailing restoration.

Manganese and copper additions differently reduced cadmium uptake and accumulation in dwarf Polish wheat (Triticum polonicum L.)

This study investigated the effects of manganese (Mn) and copper (Cu) on dwarf Polish wheat under cadmium (Cd) stress by evaluating plant growth, Cd uptake, translocation, accumulation, subcellular distribution, and chemical forms, and the expression of genes participating in cell wall synthesis, metal chelation, and metal transport. Compared with the control, Mn deficiency and Cu deficiency increased Cd uptake and accumulation in roots, and Cd levels in root cell wall and soluble fractions, but inhibited Cd translocation to shoots. Mn addition reduced Cd uptake and accumulation in roots, and Cd level in root soluble fraction. Cu addition did not affect Cd uptake and accumulation in roots, while it caused a decrease and an increase of Cd levels in root cell wall and soluble fractions, respectively. The main Cd chemical forms (water-soluble Cd, pectates and protein integrated Cd, and undissolved Cd phosphate) in roots were differently changed. Furthermore, all treatments distinctly regulated several core genes that control the main component of root cell walls. Several Cd absorber (COPT, HIPP, NRAMP, and IRT) and exporter genes (ABCB, ABCG, ZIP, CAX, OPT, and YSL) were differently regulated to mediate Cd uptake, translocation, and accumulation. Overall, Mn and Cu differently influenced Cd uptake and accumulation; Mn addition is an effective treatment for reducing Cd accumulation in wheat.

NaCl effect on Cd accumulation and cell compartmentalization in barley.

The effect of sodium chloride (NaCl) on cadmium (Cd) tolerance, uptake, translocation, and compartmentation was investigated in 3 barley genotypes. Seedlings were cultivated hydroponically in the absence of NaCl and Cd (control), in the presence of 50mM NaCl alone, in the presence of 10µM Cd alone, and in the combined addition of NaCl (50mM) and Cd (10µM). Plants were cultivated during one month under 16h light period at a minimal light intensity of 250µmolm-2s-1, a temperature of 25 ± 3°C, and 70-80% of relative humidity. Results showed that NaCl alone did not significantly affect plant development and biomass production; however, Cd alone reduced plant development rate leading to a decline in biomass production in Raihane and Giza 127 but did not affect that in Amalou. NaCl addition in Cd-treated plants accentuated the Cd effect on plant growth. NaCl limited Cd accumulation in the roots and in the shoots in all tested barley varieties by reducing Cd-absorption efficiency and the translocation of Cd from the root to the shoot. In all Cd-treated plants, cell Cd compartmentalization showed the following gradient: organelles < cell wall < vacuole. NaCl in the medium increased Cd accumulation in the soluble fraction and reduced that in organelle and cell wall fractions. Globally our results showed that, although NaCl reduces Cd accumulation in barley, it accentuates the Cd toxic effects, hence limiting the plant yield. We advise farmers to avoid barley cultivation near mine sites and its irrigation with moderately salty water, although this plant is considered as salt tolerant.

Hydrogen peroxide mediates cadmium accumulation in the root of a high cadmium-accumulating rice (Oryza sativa L.) line

Hydrogen peroxide (H2O2) is a vital signaling molecule in response to cadmium (Cd) stress in plants. However, the role of H2O2 on Cd accumulation in root of different Cd-accumulating rice lines remains unclear. Exogenous H2O2 and 4-hydroxy-TEMPO (H2O2 scavenger) were applied to investigate the physiological and molecular mechanisms of H2O2 on Cd accumulation in the root of a high Cd-accumulating rice line Lu527–8 through hydroponic experiments. Interestingly, it was found Cd concentration in the root of Lu527–8 increased significantly when exposed to exogenous H2O2, while reduced significantly when exposed to 4-hydroxy-TEMPO under Cd stress, proving the role of H2O2 in regulating Cd accumulation in Lu527–8. Lu527–8 showed more Cd and H2O2 accumulation in the roots, along with more Cd accumulation in cell wall and soluble fraction, than the normal rice line Lu527–4. In particular, more pectin accumulation, especially low demethylated pectin, was observed in the root of Lu527–8 when exposed to exogenous H2O2 under Cd stress, resulting in more negative functional groups with greater capacity to binding Cd in the root cell wall of Lu527–8. It indicated that H2O2-induced cell wall modification and vacuolar compartmentalization contributes greatly to more Cd accumulation in the root of the high Cd-accumulating rice line.

Identification of galactofuranose antigens such as galactomannoproteins and fungal-type galactomannan from the yellow koji fungus (Aspergillus oryzae).

Filamentous fungi belonging to the genus Aspergillus are known to possess galactomannan in their cell walls. Galactomannan is highly antigenic to humans and has been reported to be involved in the pathogenicity of pathogenic filamentous fungi, such as A. fumigatus, and in immune responses. In this study, we aimed to confirm the presence of D-galactofuranose-containing glycans and to clarify the biosynthesis of D-galactofuranose-containing glycans in Aspergillus oryzae, a yellow koji fungus. We found that the galactofuranose antigen is also present in A. oryzae. Deletion of ugmA, which encodes UDP-galactopyranose mutase in A. oryzae, suppressed mycelial elongation, suggesting that D-galactofuranose-containing glycans play an important role in cell wall integrity in A. oryzae. Proton nuclear magnetic resonance spectrometry revealed that the galactofuranose-containing sugar chain was deficient and that core mannan backbone structures were present in ΔugmA A. oryzae, indicating the presence of fungal-type galactomannan in the cell wall fraction of A. oryzae. The findings of this study provide new insights into the cell wall structure of A. oryzae, which is essential for the production of fermented foods in Japan.

INFLUENCE OF ANATOMY ON THE MECHANICAL RESISTANCE OF WOODS IN AN AGROFORESTRY SYSTEM

This study aimed to evaluate the influence of anatomy on the mechanical resistance of Parapiptadenia rigida (Benth.) Brenan, Peltophorum dubium (Spreng.) Taub., Eucalyptus grandis × Eucalyptus urophylla, and Schizolobium parahyba (Vell.) Blake from an agroforestry system. For this purpose, twelve 9-year-old trees were felled. To evaluate the anatomical properties, the specimens were taken from the diameter region at breast height (DBH at 1.30 m from the ground). To determine the mechanical characteristics, central planks from the DBH of the tree logs were removed to produce test specimens with dimensions of 2.5 × 2.5 × 41.0 cm. The modulus of elasticity, modulus of rupture, tension of the proportional limit, and maximum force were then evaluated. Conversely, test specimens with dimensions of 5 × 5 × 15 cm for were used for the transversal and longitudinal Janka hardness and perpendicular compression tests. The higher the cell wall fraction, vessel frequency, and ray frequency values, the better the mechanical properties. Conversely, with the increase in the fiber diameter, lumen diameter, vessel diameter, height, and width of rays, the values of the mechanical properties of wood are lower.

Boron deficiency mediates plant-insect (Diaphorima citri) interaction by disturbing leaf volatile organic compounds and cell wall functions.

In the present study, a hydroponic culture was carried out to evaluate the effects of boron deficiency on psyllid feeding process to decode the molecular/biochemical basis of host-psyllid interaction. Boron deficiency was observed to play a major role in accelerating the release of volatile organic compounds, especially methyl salicylate, affecting the shikimic acid pathway through an elevated synthesis of shikimic acid, l-phenylalanine, 3-phenylpyruvic acid and salicylic acid. These changes made citrus leaf more attractive to psyllid adults. Meanwhile, boron deficiency evidently decreased the boron concentration of leaf cell wall fractions, thereby, weakened the structural stability by affecting pectin and cellulose formations. A significant decrease of cell wall mechanical strength was observed in boron-deficiency leaf, which could be the critical reasons to reduce piercing and to increase phloem ingestion during psyllid feeding. Our study demonstrated that boron deficiency facilitated the feeding behavior of psyllid adults through elevated release of methyl salicylate, coupled with weakened mechanical properties of cell wall.

Effect of chromium stress on metal accumulation and cell wall fractions in Cosmos bipinnatus

As one of the major pollutants in the environment, chromium (Cr), a heavy metal, poses a serious threat to urban green spaces and human life and health. Cosmos bipinnatus is considered a potential accumulator of Cr, and the differences in cellular Cr distribution and compartmentalization may uncover the mechanisms involved in its tolerance to Cr. To elucidate the effects of Cr stress on C. bipinnatus and determine the mechanism of Cr tolerance in C. bipinnatus, we investigated the physiological indicators, subcellular distribution and chemical forms, cell wall fractions and their Cr contents, uronic acid content in the cell wall fractions, and Fourier transform infrared spectroscopy (FTIR) of the cell wall. The results showed that the antioxidant enzyme activities in C. bipinnatus under Cr stress and most of the Cr were fixed in the cell wall. Notably, changes in the content of pectin fractions in the cell wall affected the accumulation of Cr in the cell wall of C. bipinnatus and the stability of negatively charged groups. In addition, the carboxyl and hydroxyl groups played a role in fixing metal in various parts of the C. bipinnatus cell wall.

Tumor targeted delivery of mycobacterial adjuvant encapsulated chitosan nanoparticles showed potential anti-cancer activity and immune cell activation in tumor microenvironment.

Targeting immunotherapeutics inside the tumor microenvironment (TME) with intact biological activity remains a pressing issue. Mycobacterium indicus pranii (MIP), an approved adjuvant therapy for leprosy has exhibited promising results in clinical trials of lung (NSCLC) and bladder cancer. Whole MIP as well as its cell wall fraction have shown tumor growth suppression and enhanced survival in mice model of melanoma, when administered peritumorally. Clinically, peritumoral delivery remains a procedural limitation. In this study, a tumor targeted delivery system was designed, where chitosan nanoparticles loaded with MIP adjuvants, when administered intravenously showed preferential accumulation within the TME, exploiting the principle of enhanced permeability and retention effect. Bio-distribution studies revealed their highest concentration inside the tumor after 6h of administration. Interestingly, MIP adjuvant nano-formulations significantly reduced the tumor volume in the treated groups and increased the frequency of activated immune cells inside the TME. For chemoimmunotherapeutics studies, MIP nano-formulation was combined with standard dosage regimen of Paclitaxel. Combined therapy exhibited a further reduction in tumor volume relative to either of the MIP nano formulations. From this study a three-pronged strategy emerged as the underlying mechanism; chitosan and Paclitaxel have shown direct role in tumor cell death and the MIP nano-formulation activates the tumor residing immune cells which ultimately leads to the reduced tumor growth.

Changes in the cell walls on fruit skin of Beurré D´Anjou pears (Pyrus communis L.) associated with sunburn injury

• Sunburn reduced cuticular microcrack area and skin thickness, and increased cell wall thickness. • Neutral sugars (NS) content increased in two pectin fractions (WSP and CSP) in sunburn skin. • Hemicellulose and lignin contents increased in sunburn skin. • The expression of Exp and XTH genes increased in response to sunburn. The purpose of this work was to evaluate the effects of sunburn on pear fruit skin at the structural, biochemical, and molecular levels. Pears ( Pyrus communis L.) cv. Beurré D'Anjou were collected at the official commercial harvest time and classified into three groups based on levels of sublethal sunburn: no sunburn (S0), mild sunburn (S1), and moderate sunburn (S2). Skin anatomy was characterized by SEM imaging, cell wall components were quantified by spectrophotometric techniques, and the expression of different genes related to cell wall remodeling was measured in S0, S1, and S2 tissues. Sun-damaged skin cells had reduced size and thickened walls. In the cuticular surface, a reduction of microcracking area, correlated with the intensity of the damage, was further noted. Cell wall fractionation revealed changes in the distribution of neutral sugars (NS) following sunburn, although no differences in uronic acid (UA) content were observed in the different pectin fractions. Hemicellulose and lignin contents were significantly ( P <0.05) increased in sun-damaged tissues. Expression levels of genes encoding polygalacturonase (PcPG2), β-galactosidase (PcGAL2 and PcGAL4), xyloglucan endotransglycosylase (PcXET), and expansin (PCExp1) were increased in the skin of sun-damaged (S1 and S2) fruit. These results indicate that sunburn alters the anatomy and cell wall structure and composition of pear fruit skin, and stimulates different mechanisms involved in the acquisition of stress tolerance.

Synthesis and Characterization of Innovative Microgels Based on Polyacrylic Acid and Microalgae Cell Wall and Their Potential as Antigen Delivery Vehicles.

In this study, hybrid polyacrylic acid and Schizochytrium sp. microalgae (PAA/Schizo) microgels were synthesized by inverse emulsion assisted by ultrasound using the cell wall fraction as crosslinker. Physicochemical characterization of PAA/Schizo microgels revealed polymeric spherical particles (288 ± 39 nm) and were deemed stable and negatively charged. The produced microgels are not inherently toxic as cell viability was sustained above 80% when mice splenocytes were exposed to concentrations ranging 10-900 µg/mL. PAA/Schizo microgels were evaluated as antigen delivery nanovehicle by adsorbing bovine serum albumin (BSA); with a loading efficiency of 72% and loading capacity of 362 µg/mg. Overall, intranasally-immunized BALB/c mice showed null IgG or IgA responses against PAA/Schizo microgel-BSA, whereas soluble BSA induced significant humoral responses in systemic and mucosal compartments. Splenocytes proliferation assay upon BSA stimulus revealed positive CD4+ T cells-proliferation response in PAA/Schizo microgels-BSA group. Thus, PAA/Schizo microgels constitute functional antigen delivery vehicles of simple and ecofriendly synthesis. Moreover, the use of cell wall fraction as cross-linker agent provides an alternative use for the generation of high-value products using residual algae biomass from the oil industry. Our data suggests that the PAA/Schizo microgels are potential antigen delivery vehicles for immunotherapy development.

Whey Powder Supplementation Changes Chemical Composition, Improves Fermentation Quality, Increases the Utilization of Nutrients and Net Energy Lactation Value of Alfalfa Haylage in Kıvırcık Rams

The aim of this study was to reveal the effect of whey powder (WP) supplementation on chemical composition, silage fermentation, in vivo digestibility and net energy lactation (NEL) value of high dry matter (DM) alfalfa silage (Haylage). Alfalfa treated with different doses WP (0, 2, and 4%) were ensiled in plastic cans for 60 days. Nine Kıvırcık rams were used to estimated digestibilities of haylages in 3x3 Latin Square design with fifteen days experimental period. According to the results, the addition of WP significantly increased the DM of alfalfa haylage compared to the control whereas decreased ether extract, crude protein and crude ash. But, cell wall fraction rates of all groups were similar. Relative feed value and physical characteristics other than color improved in WP supplemented groups, and lactic acid rates increased in these groups. In terms of silo acids, the best values were found in the group with 4% WP. On the other hand, the addition of WP increased the organic matter digestibility of haylages, however the effect on other in vivo digestibility of crude protein, crude fiber, nitrogen free extract and neutral detergent fiber was insignificant. Moreover, total digestible nutrients (TDN) and NEL values of haylages were found to be improved with the addition of WP. As a result, it was concluded that in order to obtain quality haylage in the ensiling of high DM and long chopped alfalfa, WP generally can be used as an alternative source of carbohydrates and a 4% whey powder dose can be recommended in the production of haylage especially in the sense of improving silage fermentation.