Search Results (539)

Molasses, a by-product of raw sugar production, is widely used as a cost-effective carbon and nutrient source for industrial fermentations, including the production of baker’s yeast (Saccharomyces cerevisiae). Due to the cost and limited availability of molasses, efforts have been made to replace molasses with cheaper and more readily available substrates such as corn syrup. However, the quality of dry yeast drops following the replacement of molasses with corn syrup, despite the same amount of total sugar being provided. Our understanding of how molasses replacement affects yeast physiology, especially during the dehydration step, is limited. Here, we examined changes in gene expression of a strain of baker’s yeast during fermentation with increasing corn syrup to molasses ratios at the transcriptomic level. Our findings revealed that the limited availability of the key metal ions copper, iron, and zinc, as well as sulfur from corn syrup (i) reduced their intracellular storage, (ii) impaired the synthesis of unsaturated fatty acids and ergosterol, as evidenced by the decreasing proportions of these important membrane components with higher proportions of corn syrup, and (iii) inactivated oxidative stress response enzymes. Taken together, the molecular and metabolic changes observed suggest a potential reduction in nutrient reserves for fermentation and a possible compromise in cell viability during the drying process, which may ultimately impact the quality of the final dry yeast product. These findings emphasize the importance of precise nutrient supplementation when substituting molasses with cheaper substrates. Full article

Biostimulants, particularly single amino acids, can increase plant growth and crop quality, gaining significant attention. This study investigates the effects of 10 amino acids via root/foliar application on the growth, quality, taste, and volatile flavor of mini-watermelons and compares the differences between the application methods. Here, we employed electronic noses, electronic tongues, and gas chromatography–ion mobility spectrometry to investigate these effects. Root application excels in fruit growth and pectin accumulation, while foliar application boosts soluble protein and specific nutrients. Specifically, root application (except for Val) significantly increases fruit weight, with Gly being most effective for longitudinal diameter, while most amino acids (except Val/Lys) promote transverse diameter. Pectin content shows bidirectional regulation: root application of Glu/Gly/Lys/Pro/Trp/Val enhances pectin, whereas foliar application inhibits it. For taste indices, most treatments improve soluble solids (except Glu root/Arg-Leu foliar), and Ala/Asp/Glu/Gly reduce titratable acids, optimizing the sugar–acid ratio. Foliar application is more efficient for soluble protein accumulation (Ala/Glu/Gly/Pro/Leu). For nutritional quality, except for Lys, all treatments increase vitamin C and widely promote total phenolics and lycopene, with only minor exceptions, and only Arg foliar application enhances ORAC. Additionally, the results revealed that root-applied lysine and valine greatly raised the levels of hexanal and 2-nonenal, whereas foliar-applied valine significantly increased n-nonanal and (Z)-6-nonenal. Overall, we found that amino acids can considerably improve mini-watermelon production, quality, taste, and antioxidant capacity, providing theoretical and practical references for their widespread use in agriculture. Full article

To ensure the year-round efficient production of high-quality cherry tomatoes, this study evaluated how four cherry tomato cultivars can enhance yield and quality through optimized nutrient solution and supplementary lighting. Nutrient solutions (N1 and N2) were adjusted, with EC at 1.6 dS/m (N1: nitrogen 10.7 me/L, phosphorus 2.7 me/L, potassium 5.3 me/L) during flowering stage, and 2.4 dS/m (N1: nitrogen 16 me/L, phosphorus 4 me/L, potassium 8 me/L; N2: nitrogen 10.7 me/L, phosphorus 5.4 me/L, potassium 10.8 me/L) from fruit setting to harvest. N1 used standard adjustments, while N2 was optimized by adding solely with KCl and KH₂PO₄. Lighting treatments included L1 (natural light) and L2 (supplemental red/blue light). The application of N2 effectively decreased nitrate levels while it significantly enhanced the content of soluble sugars, flavor, and overall palatability, especially fruit coloring in cherry tomatoes, irrespective of supplementary lighting conditions. However, such optimization also increased sourness or altered the sugar–acid ratio. Supplementary lighting generally promoted the accumulation of soluble sugars, sweetness, and tomato flavor, although its effects varied markedly among different fruit clusters. The combination of optimized nutrient solutions and supplementary lighting exhibited synergistic effects, improving the content of soluble sugars, vitamin C, proteins, and flavor. N1 combined with L2 achieved the highest plant yield. Among the cultivars, ‘Linglong’ showed the greatest overall quality improvement, followed by ‘Baiyu’, ‘Miying’, and ‘Moka’. In conclusion, supplementary lighting can enhance the effect of nitrogen on yield and amplify the influence of phosphorus and potassium on fruit quality improvement in cherry tomatoes. The findings of this study may serve as a theoretical basis for the development of year-round production techniques for high-quality cherry tomatoes. Full article

Fruit yield and quality improvement are challenges for researchers and farmers. This study reveals that the main fruit traits of blueberry (Vaccinium ashei ‘Bluegem’) were significantly improved after hydrogen (H₂)-based irrigation, assessed by the increased single fruit weight (14.59 ± 6.66%) and fruit equatorial diameter (4.19 ± 2.39%), decreased titratable acidity, increased solid–acid and sugar–acid ratios. The enhancement of fruit quality was confirmed by the increased total volatiles, vitamin C contents, and antioxidant capacity. Using weighted protein co-expression network analysis (WPCNA), proteomic interrogation revealed that serine carboxypeptidase-like proteins I/II (SCPLI/II), ADP ribosylation factor 1/2 (ARF1/2), and UDP-glucosyltransferase 85A (UGT85A) might be functionally associated with the increased fruit weight and size driven by H₂. Reduced organic acid accumulation was caused by the regulation of the specific enzymes involved in sucrose metabolism (e.g., α-amylase, endoglucanase, β-glucosidase, etc.). H₂ regulation of fatty acid degradation (e.g., acyl CoA oxidase 1 (ACX1), acetyl CoA acyltransferase 1 (ACAA1), etc.) and phenylpropanoid metabolism were used to explain the improved fruit aroma and anthocyanin accumulation. Meanwhile, the upregulated heat shock protein 20/70 matched with the enhanced antioxidant activity. Together, this study provides a novel approach for yield and quality improvement in horticultural crops. Full article

Potassium (K), a critical macronutrient for the growth and development of Korla fragrant pear (Pyrus sinkiangensis Yu), plays a pivotal regulatory role in sugar-acid metabolism. Furthermore, K exhibits a highly specific response in near-infrared (NIR) spectroscopy compared to elements such as nitrogen (N) and phosphorus (P). Given its fundamental impact on fruit quality parameters, the development of rapid and non-destructive techniques for K determination is of significant importance for precision fertilization management. By measuring leaf potassium content at the fruit setting, expansion, and maturity stages (decreasing from 1.60% at fruit setting to 1.14% at maturity), this study reveals its dynamic change pattern and establishes a high-precision prediction model by combining near-infrared spectroscopy (NIRS) with machine learning algorithms. “Near-infrared spectroscopy coupled with machine learning can enable accurate, non-destructive monitoring of potassium dynamics in Korla pear leaves, with prediction accuracy (R²) exceeding 0.86 under field conditions.” We systematically collected a total of 9000 leaf samples from Korla fragrant pear orchards and acquired spectral data using a benchtop near-infrared spectrometer. After preprocessing and feature extraction, we determined the optimal modeling method for prediction accuracy through comparative analysis of multiple models. Multiplicative scatter correction (MSC) and first derivative (FD) are synergistically employed for preprocessing to eliminate scattering interference and enhance the resolution of characteristic peaks. Competitive adaptive reweighted sampling (CARS) is then utilized to screen five potassium-sensitive bands, specifically in the regions of 4003.5–4034.35 nm, 4458.62–4562.75 nm, and 5145.15–5249.29 nm, among others, which are associated with O-H stretching vibration and changes in water status. A comparison between random forest (RF) and BP neural network indicates that the MSC + FD–CARS–BP model exhibits the optimal performance, achieving coefficients of determination (R²) of 0.96% and 0.86% for the training and validation sets, respectively, root mean square errors (RMSE) of 0.098% and 0.103%, a residual predictive deviation (RPD) greater than 3, and a ratio of performance to interquartile range (RPIQ) of 4.22. Parameter optimization revealed that the BPNN model achieved optimal stability with 10 neurons in the hidden layer. The model facilitates rapid and non-destructive detection of leaf potassium content throughout the entire growth period of Korla fragrant pears, supporting precision fertilization in orchards. Moreover, it elucidates the physiological mechanism by which potassium influences spectral response through the regulation of water metabolism. Full article

A substrate–product switch model was proposed to describe ethanol fermentation from longan solid waste using Candida tropicalis at an initial glucose and xylose ratio of 2 to 1. The model incorporated multiple rate equations for cell growth, sugar uptake, and ethanol production along with ethanol consumption. It elucidated the following three-step mechanism: (I) sugar uptake, (II) sugar conversion, and (III) ethanol consumption concerning the effects of concentration factor (CF) and associated growth function. Optimal kinetic parameters were estimated and validated against experimental data. The identification of two critical xylose concentrations showed that ethanol consumption either preceded or coincided with xylose consumption cessation. The phenolics inhibitory effect of gallic acid, ellagic acid, pyrogallol, and catechol on cell growth and ethanol production was elucidated with relatively minimal effect. The highest ethanol concentration of 25.5 g/L was reached with corresponding ethanol mass yield and productivity of 0.30 g/g and 1.063 g/L/h, respectively. The proposed model and kinetics provide valuable insights for designing and optimizing ethanol fermentation, contributing to more sustainable and cost-effective ethanol production. Full article

Honey quality and authenticity are influenced by floral origin, processing, and storage, with implications for composition and sensory appeal. This study offers a comparative assessment of eight monofloral honey samples, representing five botanical varieties: acacia, linden, rapeseed, lavender, and thyme. For acacia, linden, and rapeseed, both producer-sourced and commercial honeys were analyzed, while lavender and thyme samples were available only from local beekeepers. The botanical origin of each sample was confirmed using morphological markers of pollen grains. Physicochemical characterization included acidity, pH, moisture content, refractive index, hydroxymethyl furfural (HMF), proline concentration, and carbohydrate profiling by HPLC-RID. Acacia honey exhibited the lowest acidity and HMF levels, alongside the highest fructose/glucose (F/G) ratios, indicating superior freshness, lower crystallization risk, and a sweeter flavor profile. In contrast, rapeseed honey showed elevated glucose levels and the lowest F/G ratio, confirming its tendency to crystallize rapidly. All samples recorded proline concentrations well above the quality threshold (180 mg/kg), supporting their authenticity and proper maturation. The estimated glycemic index (eGI) varied between 43.91 and 62.68 and was strongly inversely correlated with the F/G ratio (r = −0.98, p < 0.001). Sensory evaluation highlighted acacia honey from producers as the most appreciated across visual, tactile, and flavor attributes. Correlation analyses further revealed consistent links between sugar composition and both physical and sensory properties. Overall, the findings reinforce the value of integrated analytical and sensory profiling in assessing honey quality and authenticity. Full article

The objective of this study was to assess the effects of gallic acid (GA) on nutrient degradability, gas production, rumen fermentation, and the microbial community and its functions using in vitro fermentation methods. An in vitro experiment was conducted to test GA dose levels (0, 5, 10, 20, and 40 mg/g DM) in the cow’s diet. Based on the results of nutrient degradability, gas production, and rumen fermentation, the control group (0 mg/g DM, CON) and the GA group (10 mg/g DM, GA) were selected for metagenomic analysis to further explore the microbial community and its functions. The degradability of dry matter and crude protein, as well as total gas production, CH₄ production, CH₄/total gas, CO₂ production, and CO₂/total gas, decreased quadratically (p < 0.05) with increasing GA doses, reaching their lowest levels at the 10 mg/g DM dose. Total volatile fatty acid (VFA) (p = 0.004), acetate (p = 0.03), and valerate (p = 0.03) exhibited quadratic decreases, while butyrate (p = 0.0006) showed a quadratic increase with increasing GA doses. The 10 mg/g DM dose group had the lowest levels of total VFA, acetate, and valerate, and the highest butyrate level compared to the other groups. The propionate (p = 0.03) and acetate-to-propionate ratio (p = 0.03) linearly decreased with increasing gallic acid inclusion. At the bacterial species level, GA supplementation significantly affected (p < 0.05) a total of 38 bacterial species. Among these, 29 species, such as Prevotellasp.E15-22, bacteriumP3, and Alistipessp.CAG:435, were less abundant in the GA group, while 9 species, including Aristaeella_lactis and Aristaeella_hokkaidonensis, were significantly more abundant in the GA group. At the archaeal species level, the relative abundances of Methanobrevibacter_thaueri, Methanobrevibacter_boviskoreani, and Methanobrevibactersp.AbM4 were significantly reduced (p < 0.05) by GA supplementation. Amino sugar and nucleotide sugar metabolism, Starch and sucrose metabolism, Glycolysis/Gluconeogenesis, and Pyruvate metabolismwere significantly enriched in the GA group (p < 0.05). Additionally, Alanine, aspartate and glutamate metabolism was also significantly enriched in the GA group (p < 0.05). GA use could potentially be an effective strategy for methane mitigation; however, further research is needed to assess its in vivo effects in dairy cows over a longer period. Full article

Background: Childhood and adolescent obesity often coexist with micronutrient deficiencies and metabolic alterations, particularly in marginalized communities. Objectives: This cross-sectional study evaluated the biochemical, anthropometric, and dietary characteristics of 55 children and adolescents (ages 4–13) from Tlaltizapán, Mexico, to identify the early metabolic risk factors associated with excess weight. Methods: Nutritional intake was assessed through six-day dietary recalls and analyzed for adequacy against the national reference values. Anthropometric and biochemical indicators—including the BMI-for-age Z-score, waist-to-height ratio (WHtR), lipid profile, and plasma amino acid levels—were stratified by age and weight status. Results: Overall, 36.4% of participants were overweight or obese. Alarmingly, 89.4% of children and 94.1% of adolescents had low HDL levels, regardless of their BMIs. Several participants with a normal BMI showed elevated WHtR, triceps skinfold, and plasma branched-chain amino acids, suggesting hidden metabolic risks. The dietary analysis revealed an excess intake of sugars, proteins, and fats, alongside insufficient fiber, vitamins, and minerals. The adolescents had poorer adherence to dietary recommendations than children. Conclusions: These findings underscore the limitations of BMI alone and support the use of WHtR, skinfolds, and biochemical markers to detect preclinical obesity. Urgent, targeted nutritional strategies are needed in semi-rural areas to address the double burden of obesity and undernutrition. Full article

Golden mulberry (Morus macroura Miq.) is favored for its rich bioactive components and unique flavor, but fruit quality depends on harvest time. In the present study, golden mulberry fruits were collected at 18 (T1), 21 (T2), 24 (T3), and 27 (T4) days after flowering to investigate the impact of the harvesting stage on its physicochemical properties, antioxidant capacity, and aroma profile. Physicochemical parameters such as total phenols, total soluble solids, titratable acidity, and sensory evaluation revealed that the hardness gradually decreased with fruit maturity, whereas the weight of single fruit, total soluble solids, and solid–acid ratio increased, and soluble sugars, titratable acidity, total polyphenols and sugar–acid ratio initially increased and then decreased. Antioxidant capacity, measured by ABTS, FRAP, and DPPH assays, decreased with ripening, but stabilized at T3. In addition, the aroma components of golden mulberry fruit were analyzed by GC-MS, and it was found that aldehyde, alcohol, and ester were the main aroma components of the golden mulberry fruit. Combining the physicochemical indices, sensory evaluation, and aroma profiles, T3 period considered the optimal harvesting time. These findings offer practical guidance for the optimal harvesting and utilization of golden mulberry fruits. Full article

Cinnamomum parthenoxylon (Jack) Meisner is an important spice tree species in southern China. In in vitro cultures of C. parthenoxylon, the young stem explants can differentiate into adventitious buds and roots under different exogenous growth regulator conditions. However, the underlying regulatory mechanisms governing this differentiation process remain unclear. In this study, physiological and biochemical characteristics were measured, and transcriptomic sequencing was performed in different differentiation processes. Significant changes in physiological and biochemical parameters were observed during the differentiation of the young stems. Soluble sugars, soluble proteins, malondialdehyde (MDA), zeatin riboside (ZR), abscisic acid (ABA), gibberellin (GA) content, the (IAA + GA + ZR)/ABA ratio, and polyphenol oxidase (PPO) activity displayed contrasting expression patterns during the formation of adventitious buds and roots. The RNA-seq result revealed that the differentiation direction of young stems is regulated by the synthesis of endogenous hormones and associated signaling pathways. At the same time, phenylpropanoid metabolism and glucose metabolism pathways acted as auxiliary pathways, facilitating the formation of adventitious buds and roots. Furthermore, quantitative real-time PCR (qRT-PCR) results were highly consistent with transcriptome sequencing results. This study lays the foundation for exploring the directional differentiation of young stems in C. parthenoxylon. Full article

Lignocellulose is an important renewable biomass resource. However, at present, there is a lack of efficient and environmentally friendly catalytic systems that can selectively convert lignocellulose components into high-value sugars, and the value realization of agricultural waste (such as straw) remains challenging. Carbon-based solid acids are used in the valorization of biomass due to their simple preparation and excellent catalytic performance. In this study, the magnetic carbon microspheres catalyst was prepared using concentrated sulfuric acid and hydroxyethyl sulfonic acid as sulfonating agents. Two sulfonation catalysts were applied to the hydrolysis of typical agricultural waste (rice straw). The performance of catalyst conversion to reducing sugar was compared, and the glucose yield was lower than 30%. The sulfonation catalyst of hydroxyethyl sulfonic acid obtained a higher yield of pentose (76.67%) than that of concentrated sulfuric acid (74.25%) in 110 min. The optimal reaction conditions were found: substrate was 0.04 g straw, catalyst was 0.04 g, H₂O/γ-valerolactone ratio was 8:2 in the solvent, and the reaction time was 110 min at 140 °C. Under these conditions, the sulfonation properties of hydroxyethyl sulfonic acid as a green sulfonating agent are similar to those of concentrated sulfuric acid. Its excellent catalytic performance is attributed to the medium B/L acid density ratio on the catalyst surface. In addition, the prepared catalyst can be effectively separated from the reaction residue in the catalytic system. This work provides a green catalytic system for the high-value utilization of agricultural waste from renewable carbon sources. Full article

This study compares the physicochemical properties of Royal Gala apple snacks fresh and processed using different methods: solar-dried (SD), oven-dried at 65 °C (OD65°) and 85 °C (OD85°) and two commercial brands (CC—commercial apple C and CF—commercial apple F). Evaluated parameters included color, microstructure, acidity, sugar content, phenolic compounds, antioxidant activity, and the presence of heat-induced compounds such as 5-hydroxymethylfurfural (5-HMF) and acrylamide. Commercial samples showed more pronounced color changes and a denser microstructure, with higher browning index (BI) values. The ratio of soluble solids to titratable acidity, an indicator of sensory acceptance, was more influenced by drying methods than temperature. Total phenolic content was highest in fresh apples (123.68 mg GAE/100 g d.m.) and decreased across all drying methods, particularly in solar-dried (SD) samples (78.57 mg GAE/100 g d.m.). Antioxidant activity followed a similar trend, although SD samples performed better than expected, likely due to the retention of certain bioactive compounds. Fresh apples had the highest sugar content (43.25 mg/100 g d.m.), followed by CC (33.81 mg/100 g d.m.), OD65° (33.37 mg/100 g d.m.), CF (31.56 mg/100 g d.m.), OD85° (25.92 mg/100 g d.m.) and SD (25.01 mg/100 g d.m.). Commercial samples were sweeter and darker, with detectable levels of 5-HMF and acrylamide. The findings highlight that drying method significantly affects snack quality. While solar- and oven-dried samples better preserve bioactive compounds, industrial processes enhance sweetness and visual appeal but increase the formation of potentially undesirable compounds. These results are valuable for both consumers and producers aiming to balance sensory quality with nutritional and food safety considerations in dried apple products. Full article

Toona sinensis (A. Juss.) Roem, classified under the Toona genus of the Meliaceae family, is a fast-growing, woody species endemic to China, valued as both a vegetable crop and medicinal plant. Its seeds achieve rapid germination through a cascade of interconnected physiological, metabolic, and hormonal adaptations. Initially, physiological hydration is driven and accelerated by only two distinct phases of water imbibition. This hydration surge triggers storage reserve mobilization, with soluble sugars, proteins, and lipids undergoing rapid degradation during imbibition, while starch catabolism proceeds gradually—a pattern mirrored by progressive increases in enzymatic activities (amylase, protease, and acid phosphodiesterase (ACP)) that correlate with reserve reallocation. Concurrently, a metabolic shift from glycolysis to the pentose phosphate pathway (PPP) optimizes energy utilization, supporting germination acceleration. These biochemical changes are orchestrated by hormonal coordination: elevated gibberellin A₃ (GA₃), zeatin riboside (ZR), and indole-3-acetic acid (IAA) levels, coupled with rising GA₃/ABA, IAA/ABA, and ZR/ABA ratios, temporally aligned with germination progression. Finally, structural evidence confirms successful germination completion, as cotyledon lipid droplet breakdown and starch granule synthesis directly correlate with embryonic elongation. Together, these mechanisms underscore T. sinensis’ adaptive strategy, integrating physiological plasticity, metabolic flexibility, and endocrine precision to ensure efficient germination. Full article

This study investigates the impact of high temperature (HT) on the metabolic profile, oxidative-stress parameters, and antioxidant capacity of broccoli (Brassica oleracea var. cymosa) at different developmental stages—microgreens, seedlings, and two organs at the mature stage (leaves and head). We used spectrophotometric and chromatographic methods to quantify the concentrations of different groups and individual phenolic compounds, L-ascorbic acids, soluble sugars, proteins, glucosinolates, nitrates, pigments, oxidative-stress parameters, and antioxidant capacity. The highest number of analyzed variables significantly impacted by HT was in mature broccoli heads, with the most substantial change being an increase in proline by 168%. The lowest number of variables susceptible to HT (66%) was in the leaves of mature broccoli. The most dramatic change observed in this study was an increase in proline in seedlings by 587%. Statistical analyses showed that developmental stage plays a dominant role in shaping metabolic profiles, while HT further modulates it. Based on the measured parameters, the average contribution of developmental stage to the variance was 75%, while temperature explained 39% of the variance. The highest proportion of variance caused by temperature was seen in proline (92%), followed by kaempferol (80%), chlorophyll a/b (76%), soluble sugars (73%), total flavonoids (65%), antioxidant capacity measured by DPPH (58%), and chlorophyll/carotenoids ratio (56%). Temperature explained more variance than developmental stage for the concentration of soluble sugars, total hydroxycinnamic acids, and total tannins, which indicates an important role of these metabolites’ groups in the response of broccoli to HTs. The interaction of developmental stage and temperature explained more variance than developmental stage alone for the concentration of total proanthocyanidins, hydroxycinnamic acids, and phenolic acids. These findings underscore the complexity of metabolic regulation in broccoli and emphasize the importance of considering both developmental stage and environmental conditions when assessing its nutritional and functional properties. Full article