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Kuey teow is one of the delicacies of Guangdong, China and is a gluten-free noodle dish made from rice. It has a short storage period and extending the shelf life by quick freezing induces quality deterioration due to temperature fluctuations. To improve its freeze-thaw frozen storage quality, this paper examined the effects of hydroxypropyl corn starch (HCS), guar gum (GG), and compound phosphates (CP) on the quality of quick-frozen kuey teow during freeze-thaw cycles. The mechanism was investigated by identifying changes in the moisture status, aging degree of the starch, and textural and cooking characteristics. The results showed that all three additions improved the toughness, chewiness and steaming characteristics of the kuey teow, with CP significantly enhancing chewiness. XRD and FTIR results revealed that GG more significantly inhibited the decrease of starch crystallinity, while HCS inhibited starch aging. GG, HCS and CP all improved the hydration characteristics and water holding capacity of rice starch. GG enhances the ability of starch to bind more tightly with water, resulting in a more uniform water distribution and a more continuous and tight structure of the kuey teow. This study will provide a theoretical basis for compounding and optimizing the quick-freezing of kuey teow.

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This study investigated the influence of curdlan on the gel properties of whey protein isolate (WPI). Results demonstrated that curdlan significantly improved the water-holding capacity, gel strength and rheological properties of the WPI gels. Moreover, it promoted the unfolding of the molecular structures of WPI, which was manifested by the transition from α-helix to ß-sheet, an increase in free sulfhydryl content and a decrease in surface hydrophobicity. Furthermore, 4 % curdlan promoted the formation of WPI with uniform and compact elastic gel network structures, primarily attributed to disulphide bonds, hydrogen bonds and hydrophobic interactions. However, when the addition of curdlan exceeds 4 %, excessive entanglement of curdlan chains and steric hindrance effects hinder the unfolding and folding of protein structures, weaken their interaction, result in a loose network structure and affect the gel properties. In conclusion, this study demonstrates that curdlan can effectively improve the gelling properties of WPI, suggesting its potential application in low-calorie gel-based dairy products.

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Previous studies demonstrated that the non-thermal effects of pulsed electric fields can promote protein glycation below 40 °C, but it does not always enhance the emulsifying properties of proteins, such as in the bovine serum albumin/glucose model. Therefore, the aim of this study was to investigate the impact of non-thermal effects on the glucose glycation and emulsification properties of bovine serum albumin at 90 °C. The results of circular dichroism, surface hydrophobicity, and molecular dynamics simulations showed that the polarization effect increased the degree of glycation of bovine serum albumin-glucose conjugates from 12.82 % to 21.10 % by unfolding protein molecule, while the emulsifying stability index was increased from 79.17 to 100.73 compared with the control. Furthermore, the results of principal component analysis and Pearson correlation analysis indicated that the ionization effect and the free radicals generated by pulsed electric fields significantly (p < 0.05) inhibited browning and reduced free sulfhydryl content. This study demonstrated that pulsed electric fields combined with heating can prepare glycated proteins with good emulsifying properties in a short period of time and at temperatures lower than conventional heating while reducing energy consumption. This processing strategy has potential applications in improving the emulsifying performance of highly stable proteins.

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Bananas (Musa spp.) are one of the world's most important fruit crops and play a vital role in food security for many developing countries. Most banana cultivars are triploids derived from inter- and intraspecific hybridizations between the wild diploid ancestor species Musa acuminate (AA) and M. balbisiana (BB). We report two haplotype-resolved genome assemblies of the representative AAB-cultivated types, Plantain and Silk, and precisely characterize ancestral contributions by examining ancestry mosaics across the genome. Widespread asymmetric evolution is observed in their subgenomes, which can be linked to frequent homologous exchange events. We reveal the genetic makeup of triploid banana cultivars and verify that subgenome B is a rich source of disease resistance genes. Only 58.5% and 59.4% of Plantain and Silk genes, respectively, are present in all three haplotypes, with >50% of genes being differentially expressed alleles in different subgenomes. We observed that the number of upregulated genes in Plantain is significantly higher than that in Silk at one-week post-inoculation with Fusarium wilt tropical race 4 (Foc TR4), which confirms that Plantain can initiate defense responses faster than Silk. Additionally, we compared genomic and transcriptomic differences among the genes related to carotenoid synthesis and starch metabolism between Plantain and Silk. Our study provides resources for better understanding the genomic architecture of cultivated bananas and has important implications for Musa genetics and breeding.

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Background: Despite poor oral hygiene, the Baiku Yao (BKY) ethnic group in China presents a low prevalence of dental caries, which may be related to genetic susceptibility. Due to strict intra-ethnic marriage rule, this ethnic has an advantage in studying the interaction between genetic factors and other regulatory factors related to dental caries. Methods: Peripheral blood from a caries-free adult male was used for whole genome sequencing, and the BKY assembled genome was compared to the Han Chinese genome. Oral saliva samples were collected from 51 subjects for metabolomic and metagenomic analysis. Multiomics data were integrated for combined analysis using bioinformatics approaches. Results: Comparative genomic analysis revealed the presence of structural variations in several genes associated with dental caries. Metabolomic and metagenomic sequencing demonstrated the caries-free group had significantly higher concentration of antimicrobials and higher abundance of core oral health-related microbiota. The functional analysis indicated that cationic antimicrobial peptide resistance and the lipopolysaccharide biosynthesis pathway were enriched in the caries-free group. Conclusions: Our study provided new insights into the specific regulatory mechanisms that contribute to the low prevalence of dental caries in the specific population and may provide new evidence for the genetic diagnosis and control of dental caries.

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Cassava is a crucial crop that makes a significant contribution to ensuring human food security. However, high-quality telomere-to-telomere cassava genomes have not been available up to now, which has restricted the progress of haploid molecular breeding for cassava. In this study, we constructed two nearly complete haploid resolved genomes and an integrated, telomere-to-telomere gap-free reference genome of an excellent cassava variety, 'Xinxuan 048', thereby providing a new high-quality genomic resource. Furthermore, the evolutionary history of several species within the Euphorbiaceae family was revealed. Through comparative analysis of haploid genomes, it was found that two haploid genomes had extensive differences in linear structure, transcriptome features, and epigenetic characteristics. Genes located within the highly divergent regions and differentially expressed alleles are enriched in the functions of auxin response and the starch synthesis pathway. The high heterozygosity of cassava 'Xinxuan 048' leads to rapid trait segregation in the first selfed generation. This study provides a theoretical basis and genomic resource for molecular breeding of cassava haploids.

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The valorization of industrial fruit and vegetable waste has gained significant attention due to the environmental concerns and economic opportunities associated with its effective utilization. This review article comprehensively discusses the application of subcritical and supercritical fluid technologies in the valorization process, highlighting the potential benefits of these advanced extraction techniques for the recovery of bioactive compounds and unconventional oils from waste materials. Novel pressurized fluid extraction techniques offer significant advantages over conventional methods, enabling effective and sustainable processes that contribute to greener production in the global manufacturing sector. Recovered bio-extract compounds can be used to uplift the nutritional profile of other food products and determine their application in the food, pharmaceutical, and nutraceutical industries. Valorization processes also play an important role in coping with the increasing demand for bioactive compounds and natural substitutes. Moreover, the integration of spent material in biorefinery and biorefining processes is also explored in terms of energy generation, such as biofuels or electricity, thus showcasing the potential for a circular economy approach in the management of waste streams. An economic evaluation is presented, detailing the cost analysis and potential barriers in the implementation of these valorization strategies. The article emphasizes the importance of fostering collaboration between academia, industry, and policymakers to enable the widespread adoption of these promising technologies. This, in turn, will contribute to a more sustainable and circular economy, maximizing the potential of fruit and vegetable waste as a source of valuable products.

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Selenium nanoparticles (SeNPs) are among the emerging selenium supplements because of their high bioactivity and low toxicity. However, bare SeNPs are prone to activity loss caused by aggregation and sedimentation. This study aims to stabilize SeNPs with curdlan (CUR), a polysaccharide, to maintain or even enhance their biological activity. Herein, the stable SeNPs were constructed via the unique conformational transition of CUR induced by alkali-neutralization (AN) pretreatment. The physicochemical properties and structures of the prepared SeNPs were characterized by dynamic light scattering (DLS), UV-visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and free-radical-scavenging activity assays. The results show that most SeNPs are stabilized within the triple helix of CUR that has been pretreated with high-intensity AN treatment. These amorphous, small-sized (average size was 53.6 ± 17.7 nm), and stabilized SeNPs have significantly enhanced free-radical-scavenging ability compared to the control and can be well-stabilized for at least 240 days at 4 °C. This work indicates that CUR, as a food additive, can be used to well-stabilize SeNPs by AN pretreatment and provides a facile method to prepare and enhance the stability and bioactivity of SeNPs via triple-helix conformational transition.

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Schistosomiasis is a neglected tropical disease of humans caused by blood flukes of the genus Schistosoma, the only dioecious parasitic flatworm. Although aspects of sex determination, differentiation and reproduction have been studied in some Schistosoma species, almost nothing is known for Schistosoma japonicum, the causative agent of schistosomiasis japonica. This mainly reflects the lack of high-quality genomic and transcriptomic resources for this species. As current genomes for S. japonicum are highly fragmented, we assembled and report a chromosome-level reference genome (seven autosomes, the Z-chromosome and partial W-chromosome), achieving a substantially enhanced gene annotation. Utilizing this genome, we discovered that the sex chromosomes of S. japonicum and its congener S. mansoni independently suppressed recombination during evolution, forming five and two evolutionary strata, respectively. By exploring the W-chromosome and sex-specific transcriptomes, we identified 35 W-linked genes and 257 female-preferentially transcribed genes (FTGs) from our chromosomal assembly and uncovered a signature for sex determination and differentiation in S. japonicum. These FTGs clustering within autosomes or the Z-chromosome exhibit a highly dynamic transcription profile during the pairing of female and male schistosomula, thereby representing a critical phase for the maturation of the female worms and suggesting distinct layers of regulatory control of gene transcription at this development stage. Collectively, these data provide a valuable resource for further functional genomic characterization of S. japonicum, shed light on the evolution of sex chromosomes in this highly virulent human blood fluke, and provide a pathway to identify novel targets for development of intervention tools against schistosomiasis.

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Winter rapeseed (Brassica rapa L.) is an important overwintering oilseed crop that is widely planted in northwest China and suffers chronic low temperatures in winter. So the cold stress becomes one of the major constraints that limit its production. The currently existing genomes limit the understanding of the cold-tolerant genetic basis of rapeseed. Here we assembled a high-quality long-read genome of B. rapa "Longyou-7" cultivar, which has a cold-tolerant phenotype, and constructed a graph-based pan-genome to detect the structural variations within homologs of currently reported cold-tolerant related genes in the "Longyou-7" genome, which provides an additional elucidation of the cold-tolerant genetic basis of "Longyou-7" cultivar and promotes the development of cold-tolerant breeding in B. rapa.

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Actinomycete strain YIM PH20352, isolated from the rhizosphere soil sample of Panax notoginseng collected in WenShang, Yunnan Province, China, exhibited antifungal activity against some phytopathogenic fungi. The structures of bioactive molecules, isolated from the ethyl acetate extract of the fermentation broth of the strain, were identified as rabelomycin (1) and dehydrorabelomycin (2) based on extensive spectroscopic analyses. Compound 1 exhibited antifungal activity against four tested root-rot pathogens of the Panax notoginseng including Plectosphaerella cucumerina, Alternaria panax, Fusarium oxysporum, and Fusarium solani with the MIC values at 32, 64, 128, and 128 µg/mL, respectively. Compound 2 exhibited antifungal activity against F. oxysporum, P. cucumerina, F. solani, and A. panax with the MIC values at 64, 64, 128, and 128 µg/mL, respectively. Based on the phylogenetic analyses, the closest phylogenetic relative of strain YIM PH20352 is Streptomyces cellulosae NBRC 13027 T (AB184265) (99.88%), so strain YIM PH20352 was identified as Streptomyces cellulosae. To the best of our knowledge, this is the first report of rabelomycin and rabelomycin-type antibiotics from Streptomyces cellulosae and their antifungal activity against root-rot pathogens of the Panax notoginseng.

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Background: The lack of suitable diagnostic tools contributes to the high prevalence of tuberculosis (TB) worldwide. Serological tests, based on multiple target antigens, represent an attractive option for diagnosis of this disease due to their rapidity, convenience, and low cost. Methods: Measures to reduce non-specific reactions and thereby improve the specificity of serological tests were investigated, including blocking antibodies against common bacteria in serum samples and synthesizing polypeptides covering non-conserved dominant B-cell epitopes of antigens. In addition, a fusion polyprotein containing HspX and eight other antigen sequences was constructed and expressed to increase overall sensitivity of the tests. Results: Inclusion of Escherichia coli lysate partially increased the specificity of the serological tests, while synthesis and inclusion of peptides containing non-conserved sequences of TB antigens as well as dominant B-cell epitopes reduced non-specific reactions without a decrease in sensitivity of the tests. A polyprotein fusing HspX and eight other antigen sequences was constructed and displayed 60.2% sensitivity, which was higher than that of HspX and the other individual antigen segments. Moreover, the specificity of the polyprotein was 93.8%, which was not significantly decreased when compared with HspX and the other individual antigen segments. Conclusions: The roles of the fusion polyprotein in the humoral immune response against TB infection were demonstrated and provide a potential novel approach for the development of TB diagnostics.

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Triple-helical aggregates (THAs) have been proven to affect the biological activities and functional properties of triple-helix polysaccharides. Thus, it's urgent to seek a method to reduce the size of THAs while preserving independent triple helices (ITHs). In this study, the effects of alkali-neutralization (AN) treatment on THAs and ITHs of curdlan were studied. The positive values of the Congo red test data (R2>0.99) fitted using a Logistic model indicated that AN treatment (CNaOH/HCl>0.28 mol/L) facilitated the disaggregation of THAs. Congo red test, sedimentation test, and turbidity test showed that AN treatment (CNaOH/HCl = 1.0 mol/L) significantly reduced the size of THAs to approximately 1 µm while effectively increasing the relative amount of ITHs to approximately 199 %. Fourier transform infrared spectroscopy and X-ray diffraction analysis showed that AN treatment basically unchanged the primary structure of curdlan chains, but affected the crystalline structure and the intermolecular and intramolecular hydrogen bonding of curdlan.

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To study dextran degradation by sonoenzymolysis, the degradation rate, the change of molecular weight, the mass fractions of fragments of certain molecular weight, and the degradation kinetics were analyzed and compared with the corresponding parameters under ultrasonic and enzymolysis treatments. The degradation rate improved greatly and the time required to stabilize the rate was shortened compared with ultrasonic treatment, for example, more than 120 min was needed at 4 W/mL for ultrasonic treatment before stabilization with the degradation rate of 77.41%, whereas 80 min was needed for sonoenzymolysis treatment with the degradation rate of 91.44%. A lower molecular weight limit was established (7.15 × 104 Da at 4 W/mL for sonoenzymolysis treatment compared with 19.61 × 104 Da at 4 W/mL for ultrasonic treatment), with decreased time to approach the new limiting molecular weight (80 min compared with more than 120 min). The mass fraction of 104-105 Da fragment increased (61.02% at 4 W/mL for sonoenzymolysis treatment compared with 42.98% at 4 W/mL for ultrasonic treatment) and the dextran degradation kinetics for sonoenzymolysis under lower ultrasonic intensity fitted the Malhotra model well. Sonoenzymolysis treatment at the ultrasonic intensity of 4 W/mL for 80 min resulted in more 104-105 Da fragments in a shorter time. The results indicated that sonoenzymolysis can be applied as an efficient method to obtain clinical dextran.

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The applications of dextran depend not only on the molecular weight but also on the types and number of branches. In this study, dextran generated from Leuconostoc mesenteroides (L.M.CICC-20724) was characterized by fourier-transform infrared spectrum and nuclear magnetic resonance spectroscopy. Our analyses showed that dextran was a polysaccharide composed of d-glucose units with predominantly α(1 â†’ 6) linkages in the main chain and few α(1 â†’ 3) linkages in the branch. Periodate oxidation, a classic chemical method, was usually combined with Smith degradation and gas chromatography to analyze glycosidic linkages in polysaccharide quantitatively. In this study, we calculated the exact straight-chain/branched-chain ratio in the dextran using periodate oxidation only. The ratios obtained by periodate oxidation only were compared to the ratios obtained by nuclear magnetic resonance. The results showed that the ratios of the two groups were nearly equal, and the average relative error between the two groups was 0.83%. This method was evaluated and found to be accurate and stable. This technique provided a convenient and straightforward chemical method for the quantitative analysis of the straight-chains and branched-chains in polysaccharides which had a similar structure. The ratios during the enzymatic synthesis process of dextran were analyzed by this method and were found to be stable with a high level of approximately 95% on average.

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BACKGROUND: The identification and characterization of epitopes facilitate the discovery and development of new therapeutics, vaccines and diagnostics for infectious diseases. In this study, we developed a glutathione S-transferase (GST)-peptide fusion protein microplate array for the identification of linear B-cell epitopes and applied this novel method to the identification of linear B-cell epitopes of SjSP-13, an immunodiagnostic biomarker of schistosomiasis japonica. METHODS: SjSP-13 was divided into 17 overlapped peptides (p1-17), and the coding sequence of each peptide was obtained by annealing two complementary oligonucleotides. SjSP-13 peptides were expressed by fusion with an N-terminal GST tag and a C-terminal 6xHis tag. The GST-peptide-His fusion protein was specifically bound to the Immobilizer Glutathione MicroWell 96-well plates without purification. SjSP-13 peptides and core epitopes that could be recognized by sera from schistosomiasis patients were identified by ELISA and confirmed by Western blot analysis. The receiver operating characteristic (ROC) analysis was performed to determine the diagnostic validity of the identified peptide. RESULTS: Full-length GST-peptide-His fusion proteins were successfully expressed and specifically bound to the Immobilizer Glutathione MicroWell 96-well plates. Two adjacent peptides (p7 and p8) were found to be highly immunogenic in humans. The core epitope of p7 and p8 is an 11-aa peptide (80KCLDVTDNLPE90) and an 8-aa peptide (90EKIIQFAE97), respectively. The area under the ROC curve (AUC) value of the peptide which contains the two identified epitopes is 0.947 ± 0.019. The diagnostic sensitivity and specificity of the peptide is 76.7% (95% CI: 68.8-84.5%) and 100%, respectively. CONCLUSIONS: 90EKIIQFAE97 and 80KCLDVTDNLPE90 are the two linear epitopes of SjSP-13 recognized by patient sera, and could be potential serological markers for schistosomiasis japonica.

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Schistosoma japonicum eggs trapped in host liver secretes microRNA (miRNA)-containing extracellular vesicles (EVs) that can be transferred to host cells. Recent studies demonstrated that miRNAs derived from plants can modulate gene expression and phenotype of mammalian cells in a cross-kingdom manner. In this study, we identified a Schistosoma japonicum miRNA (e.g., Sja-miR-3096) that is present in the hepatocytes of mice infected with the parasite and has notable antitumor effects in both in vitro and in vivo models. The Sja-miR-3096 mimics suppressed cell proliferation and migration of both murine and human hepatoma cell lines by targeting phosphoinositide 3-kinase class II alpha (PIK3C2A). We generated a murine hepatoma cell line that stably expressed the pri-Sja-miR-3096 gene and demonstrated cross-species processing of the schistosome pri-miRNA to the mature Sja-miR-3096 in the mammalian cell. Importantly, inoculation of this cell line into the scapula and livers of mice led to a complete suppression of tumorigenesis of the hepatoma cells. Moreover, tumor weight was significantly reduced on intravenous administration of Sja-miR-3096 mimics. Thus, the schistosome miRNA-mediated antitumor activity occurs in host liver cells during schistosome infection, which may strengthen resistance of host to liver cancer, and discovery and development of such miRNAs may present promising interventions for cancer therapy.

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Actinomycete strain YIM PH20520, isolated from the rhizosphere soil sample of Panax notoginseng collected in Wenshang, Yunnan Province, China, exhibited antifungal activity against root-rot pathogens of the Panax notoginseng. The structures of bioactive molecules, isolated from the ethyl acetate extract of the fermentation broth of the strain, were identified as echinosporin (1) and 7-deoxyechinosporin (2) based on extensive spectroscopic analyses. 1 exhibited antifungal activity against four tested root-rot pathogens of Panax notoginseng include Fusarium oxysporum, Fusarium solani, Alternaria panax, and Phoma herbarum with the MIC value at 64, 64, 32, and 64 µg/mL, respectively. 2 exhibited antifungal activities against F. oxysporum, F. solani, A. panax, and P. herbarum with the MIC value at 128, 128, 64, and 128 µg/mL, respectively. Based on the phylogenetic analyses, the closest phylogenetic relative of strain YIM PH20520 is Amycolatopsis speibonae JS72T (97.69%), so strain YIM PH20520 was identified as Amycolatopsis strain. To the best of our knowledge, this is the first report of echinosporin antibiotics isolated from Amycolatopsis strain besides Streptomyces strain and their antifungal activity against four tested root-rot pathogens of the Panax notoginseng. The results provide a reliable evidence for the following related biosynthetic investigations on Amycolatopsis strain YIM PH20520 due to echinosporins antibiotics' unique tricyclic acetal-lactone structures.

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Schistosomiasis japonica is one of the most prevalent parasitic diseases in China. The scarcity of effective diagnostic tools is a major factor that contributes to the high prevalence of schistosomiasis japonica. SjSP-13 is a promising serological diagnostic biomarker of the disease. However, it is unclear whether polymorphisms in SjSP-13 affect its diagnostic efficacy and immunogenicity. Here, we found the SjSP-13 gene was highly polymorphic, and all the alleles of the gene were clustered into two clades, clade A and B. SjSP-13.6 and SjSP-13.25, the representative alleles of clade A and B, were produced in Escherichia coli. The diagnostic value of SjSP-13.6 (AUC = 0.983 ± 0.006), was found to be similar to the SjSP-13.25 (AUC = 0.973 ± 0.009) by receiver operating characteristic (ROC) analysis. SjSP-13.6 and SjSP-13.25 have the same specificity (96.7%), while the sensitivity of SjSP-13.6 (90.4%) is slightly but not significantly higher than SjSP-13.25 (85.2%). The combination use of the two alleles (SjSP-13.6/25) didn't increase the diagnostic performance of SjSP-13 as the AUC value of SjSP-13.6/25 is 0.977 ± 0.009, lower than individual SjSP-13.6 (AUC = 0.983 ± 0.006). In addition, we found the immunogenicity of clade A alleles is significantly higher than clade B in Schistosoma japonicum naturally infected animals and patients, as the mean antibody levels of SjSP-13.6 was significantly higher than SjSP-13.25. We conclude that polymorphisms of the SjSP-13 gene should not affect its diagnostic efficacy, and it is not necessary to combine the alleles of the two clades for diagnosis of schistosomiasis.

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BACKGROUND: The challenges posed by Mycobacterium tuberculosis infection require the gradual removal of the pool of latent tuberculosis infection (LTBI). The current cell-immune-based diagnostic tests used to identify LTBI individuals have several irreversible drawbacks. In the present study, we attempted to identify novel diagnostic antigens for LTBI. METHODS: A high-throughput glutathione S-transferase (GST)-fusion technology was used to express over 409 TB proteins and sera from LTBI and healthy individuals was used to interrogate these GST-TB fusion proteins. RESULTS: Of 409 TB proteins, sixty-three reacted seropositive and defined the immuno-ORFeome of latent M. tuberculosis. Within the immuno-ORFeome, the rare targets were predominantly latency-associated proteins and secreted proteins, while the preferentially recognized antigens tended to be transmembrane proteins. Six of novel highly-reactive antigens had the potential to distinguish LTBI from active TB and healthy individuals. A multiple-antigen combination set was selected through analysis of various combinations. A panel of 94 archived serum samples was used to validate the diagnostic performance of the multiple-antigen combination set, which had sensitivity of 66.1% (95% CI 52.9, 77.4) and specificity of 87.5% (95% CI 70.1, 95.1). CONCLUSION: These results provide experimental evidence of the immunogenicity of novel TB proteins that are suitable for the development of serodiagnostic tools for LTBI.

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