Sucrose/D-Fructose/D-Glucose Assay Kit

Many of the enzymatic test kits are official methods of prestigious organisations such as the Association of Official Analytical Chemicals (AOAC) and the American Association of Cereal Chemists (AACC) in response to the interest from oenologists. Megazyme decided to use its long history of enzymatic bio-analysis to make a significant contribution to the wine industry, by the development of a range of advanced enzymatic test kits. This task has now been successfully completed through the strategic and comprehensive process of identifying limitations of existing enzymatic bio-analysis test kits where they occurred, and then using advanced techniques, such as molecular biology (photo 1), to rapidly overcome them. Novel test kits have also been developed for analytes of emerging interest to the oenologist, such as yeast available nitrogen (YAN; see pages 2-3 of issue 117 article), or where previously enzymes were simply either not available, or were too expensive to employ, such as for D-mannitol analysis.

It is without doubt that testing plays a pivotal role throughout the whole of the vinification process. To produce the best possible quality wine and to minimise process problems such as “stuck” fermentation or troublesome infections, it is now recognised that if possible testing should begin prior to harvesting of the grapes and continue through to bottling. Traditional methods of wine analysis are often expensive, time consuming, require either elaborate equipment or specialist expertise and frequently lack accuracy. However, enzymatic bio-analysis enables the accurate measurement of the vast majority of analytes of interest to the wine maker, using just one piece of apparatus, the spectrophotometer (see previous issue No. 116 for a detailed technical review). Grape juice and wine are amenable to enzymatic testing as being liquids they are homogenous, easy to manipulate, and can generally be analysed without any sample preparation.

In this study a plant-based spread was developed using dextran-enriched ingredients derived from pea flours, supplemented with defatted durum wheat germ and almond flour. Optimization of fermentation with Leuconostoc pseudomesenteroides DSM 20193, both with and without enzymatic hydrolysis, aimed to enhance exopolysaccharide production and the nutritional value of pea flours. Best results were achieved through enzymatic hydrolysis with Veron PS protease followed by fermentation at 25°C, resulting in elevated dextran levels and increased peptides and total free amino acid concentration in green and yellow pea-based ingredients. The yellow pea-based ingredient was selected for the final plant-based spread formulation, blended at 35% w/w, with 45% w/w defatted durum wheat germ, and 20% w/w almond flour. The resultant spread exhibited elastic and solid-like characteristics like milk-based spreadable cheese and yogurt, boasting 'high protein' (12.49 g/100g) and 'high fiber' (11.01 g/100g) designations. It maintained chemical, biochemical, and microbiological stability over a 10-day shelf-life under refrigerated conditions. Sensory evaluation confirmed the acceptability of the plant-based spread (PBS), highlighting a well-balanced aroma and a grainy, adhesive texture. This research underscores the potential of an integrated approach utilizing food-grade enzymes and fermentation for the in-situ production of dextran to create innovative, clean label, and plant-based foods.

Biological nitrogen fixation (BNF) occurring in the rhizosphere is a sustainable source of nitrogen for plants. BNF in cereal crops can be promoted by inoculation of a single or consortium of associative and endophytic diazotrophs. Creating a successful nitrogen-fixing biofertilizer necessitates the study of the core microbiome of the plant rhizosphere and the functional relationship of the members. This study compares the endosphere and rhizoplane microbial diversity of three aromatic landraces and one high-yielding variety of rice using culture-independent methods. The V3-V4 variable regions of 16S rRNA were used for amplicon sequencing of soil DNA. Patescibacteria, Planctomycetota, and Proteobacteria were the predominant phyla in all four genotypes. Richness (Chao-1 and ACE) and microbial diversity indices (Shannon and Simpson indices) showed that microbial diversity among the genotypes varies subtly at the phylum level. Beta diversity analysis with the phylum identified and comparisons of the microbiome at the genus level revealed a more prominent effect of plant genotype on microbial diversity. Canonical component analysis drew a correlation between microbial diversity in each genotype with the sugar and N content of these landraces. Paraburkholderia was identified as one of the major OTUs among the known nitrogen fixing followed by Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium group, Azospirillum, Hebarspirillum, and Azotobacter.

The main mango cultivars produced in the southern Pacific region of Mexico are Ataulfo, Manila, Haden, and Criollo. However, mineral, nutritional, and nutraceutical composition studies are limited. This study aimed to evaluate the effect of cultivars on the nutritional, mineral, and nutraceutical qualities of mango produced in Mexico. The cultivar significantly affected (p ≤ 0.05) the fruit composition across these indices. Criollo had the highest potassium, magnesium, sodium, and zinc concentrations, while Haden showed the highest calcium content. Manila had the highest iron content, contributing 0.76% of the recommended daily intake. Ataulfo and Haden were statistically similar in manganese content, both higher than Criollo, with Ataulfo reaching the maximum copper concentration. Ataulfo also had the highest sugar content, while Criollo had the most dietary fiber (3.1%), double that of Ataulfo and Haden. Haden had the lowest dry matter (14.8%) and lowest protein content (0.46%), with Manila showing the lowest ash content. The cultivars also differed in nutraceutical composition: Ataulfo was highest in total phenols, DPPH, and vitamin A; Haden in carotenoids and flavonoids; and Criollo in vitamin C. Cultivar selection induces changes in mango nutritional composition.

Fire damage can significantly impact fruit productivity in orchards. However, the effects of nonlethal fire injuries on the reproductive development of apple trees remain poorly understood. To investigate these effects, we implemented three treatments: trunk girdling to simulate fire injury to xylem, defoliation of a third of the canopy (simulated crown fire injury), and a combined treatment (simulated surface fire injury), alongside a control. The experiment was conducted during the 2021–22 growing season using a randomised block design with four biological replicate plots. Girdling was less effective than crown and surface fire treatments in influencing fruit composition during the current growing season, and flowering and fruiting in the following season. The crown and surface fire treatments induced localised detrimental effects on fruit sugar and titratable acidity while stimulating peel blush. Additionally, these treatments led to reduced starch reserves by harvest, which likely disrupted subsequent flowering and crop load near the previously defoliated sections of the canopy. When surface fires damage leaves near the base of the canopy in addition to the trunk, fruit production in the lower part of the canopy is more likely to be compromised in the following season. Crown fires, which cause leaf loss near the apex of the canopy, appear to be particularly detrimental to tree productivity, as the top defoliation treatment impaired carbohydrate reserves in shoot terminals and roots. In conclusion, fire-induced loss of leaf area during fruit growth alters fruit composition in the current growing season and may lead to lower yields in the subsequent season.

Entomophilous dioecious plants may present opportunities to conserve insect populations as they often possess flowers accessible to a diversity of visitors and potential pollinators. Additionally, flowers of each sex can vary in the nutrients they provide. Two South Australian populations of the largely dioecious arid zone shrub Pimelea microcephala subsp. microcephala (Thymelaeaceae) were investigated to determine the conservation utility of the species to conserve insect populations by assessing floral visitor and pollinator diversity and the nutritional quality of pollen and nectar. Fifty-five visitors representing species in six insect orders were recorded at Baron Station, while 49 visitors from three insect orders were recorded at Clements Gap. Thirty-nine of the observed visitors were captured, of which two species of Hymenoptera, two of Diptera and one of Hemiptera were carrying pollen and thus potential pollinators. Visitation rates were higher for male than female plants at Clements Gap, but the reverse at Baron Station. Pollen from male plants had low protein content (2.5% dried weight (DW)) compared to co-flowering hermaphroditic angiosperms at the sites (5.3–14.0% DW). In contrast, floral extracts from male plants had at least 2× greater cumulative sugar concentrations than those of females at the same site, but female extracts had at least 4× higher protein content than male ones. As a food resource plant, P. microcephala subsp. microcephala may represent an important plant species for revegetation efforts that support the conservation of insect diversity in arid regions and throughout its broad range.

Inconsistent yield of subtropical table grape across seasons is often associated with low carbohydrate reserves during flowering. In an attempt to increase TNC and thus yield, sucrose was injected into treated trunks during periods of high carbohydrate demand (i.e., between budburst and flowering). Total non-structural carbohydrate (TNC) concentration dynamics were assessed in the grapevine root and trunk tissues of both control and treated vines. In the control (untreated) vines, the TNC concentration in root and trunk tissues was 13.5% and 7.5% w/dw at leaf fall and 7.2% and 3.7% w/dw at flowering, respectively. This decrease in carbohydrate reserve was estimated at ~500 g/vine and is associated with the re-establishment of the plant canopy in early spring. Carbohydrate reserves remained stable or rose slightly between flowering and harvest and recovered between crop harvest and leaf fall. In treated vines, a constantly pressurised low-pressure in situ trunk injection system (69 kPa) with 5% w/v sucrose solution over 45 days from budburst (to flowering), in each of the two seasons, delivered a widely variable amount of sucrose into each vine with variation ascribed to the amount of internal dead wood in the trunk. In the best circumstances, an average of 150 g sucrose/vine/season was injected, and sucrose-injected vines had higher trunk TNC reserve (4.1% compared to 3.6% w/dw in the control) at flowering. A δ¹³C (‰) analysis confirmed the presence of injected sucrose in the shoot at flowering. However, the correlation between the amount of loaded sucrose and δ13C in young shoot tissue was poor, indicative of variable partitioning patterns. Inflorescence number per vine and berry yield were markedly higher in sucrose-injected vines, but differences were not significant given the high variation between vines. The addition of KCl to the sucrose solution and use of the healthy vines are recommended to increase sucrose loading using the injection method to address inconsistent yielding of subtropical table grape.

The escalating issue of light pollution in urban environments poses multifaceted challenges, affecting not only the nocturnal sky but also exerting intricate influences on plant physiology. This study delves into the physiological responses of an urban ornamental tree, Populus alba L. clone DI-1, to varying intensities of streetlamp LED night lighting (NL), a shift from traditional High-Pressure Sodium lamps. The investigation “sheds light” on the molecular pathways underlying observed physiological regulations, aiming to offer a comprehensive understanding of the manifold effects of NL on this tree species. NL altered tree architecture, i.e. increased branch length and diameters, underscoring the dynamic response of trees to nocturnal artificial lighting conditions. Regarding tree physiology, the NL-triggered net CO₂ assimilation (P_n) during the night resulted in limitations in stomatal conductance during daylight hours. This led to a reduction in P_n, particularly during dawn, hindering the quantum yield for the reduction of end acceptors of PSI. Changes in chlorophyll a-to-b proportion and overall concentration, electron transport chain, and gene expression further highlight the intricate interplay between NL and plant metabolic regulation. Notably, the increased gene expression of sugar transporters in both NL trees suggested a responsive shift in sugar and starch metabolism. This was reflected in the absence of a starch accumulation during daylight hours in NL leaves. The study emphasizes the need for a holistic approach to urban lighting, considering its profound impact on photosynthesizing citizens. These findings highlight the pressing need for the development of innovative lighting spectra with reduced impact on plant physio-chemistry while ensuring visibility for citizen safety.

The effects of transient increases in UVB radiation on plants are not well known; whether cumulative damage dominates or, alternately, an increase in photoprotection and recovery periods ameliorates any negative effects. We investigated photosynthetic capacity and metabolite accumulation of grapevines (Vitis vinifera Cabernet Sauvignon) in response to UVB fluctuations under four treatments: fluctuating UVB (FUV) and steady UVB radiation (SUV) at similar total biologically effective UVB dose (2.12 and 2.23 kJ m^-2 day^-1), and their two respective no UVB controls. We found a greater decrease in stomatal conductance under SUV than FUV. There was no decrease in maximum yield of photosystem II (F_v/F_m) or its operational efficiency (ɸ_PSII) under the two UVB treatments, and F_v/F_m was higher under SUV than FUV. Photosynthetic capacity was enhanced under FUV in the light-limited region of rapid light-response curves but enhanced by SUV in the light-saturated region. Flavonol content was similarly increased by both UVB treatments. We conclude that, while both FUV and SUV effectively stimulate acclimation to UVB radiation at realistic doses, FUV confers weaker acclimation than SUV. This implies that recovery periods between transient increases in UVB radiation reduce UVB acclimation, compared to an equivalent dose of UVB provided continuously. Thus, caution is needed in interpreting the findings of experiments using steady UVB radiation treatments to infer effects in natural environments, as the stimulatory effect of steady UVB is greater than that of the equivalent fluctuating UVB.

Seed aging is a complicated process influenced by environmental conditions, impacting biochemical processes in seeds and causing deterioration that results in reduced viability and vigor. In this study, we investigated the seed aging process of ridge gourd, which is one of the most exported commercial seeds in Thailand using sequential window acquisition of all theoretical fragment ion spectra mass spectrometry. A total of 855 proteins were identified among the two groups (0 d/15 d and 0 d/30 d). The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses of differentially expressed proteins revealed that in ridge gourd seeds, the aging process altered the abundance of proteins related to the oxidative stress response, nutrient reservoir, and metabolism pathway. The most identified DEPs were mitochondrial proteins, ubiquitin–proteasome system proteins, ribosomal proteins, carbohydrate metabolism-related proteins, and stress response-related proteins. This study also presented the involvement of aconitase and glutathione pathway-associated enzymes in seed aging, with aconitase and total glutathione being determined as possible suggestive biomarkers for aged ridge gourd seeds. This acquired knowledge has the potential to considerably improve growing methods and seed preservation techniques, enhancing seed storage and maintenance.

In recent years, there has been increasing interest in utilizing Traditional Chinese Medicine principles and natural bioactive compounds to combat age-related ailments and enhance longevity. A Cordyceps sinensis mycelium hydroethanolic extract (CsEx), which was standardized in cordycepin and adenosine using UHPLC-DAD, was investigated for its adaptogenic properties using in vitro assays and a double-blind, placebo-controlled clinical trial involving 40 subjects. The CsEx demonstrated activity at a concentration of 0.0006%, significantly increasing sirtuin expression (SirT1: +33%, SirT3: +10%, SirT6: +72%, vs. CTR, p < 0.05) and NAD+ synthesis in HaCat cells (+20% vs. CTR, p < 0.001). Moreover, the CsEx boosted ATP production by 68% in skin cells, correlating with higher skin energy values (+52.0% at D₂₈, p < 0.01) in the clinical trial. Additionally, CsEx notably reduced cytosolic reactive oxygen species (ROS) by 30% in HaCaT cells (p < 0.05) and enhanced collagen production both in vitro (+69% vs. CTR, p < 0.01) and in vivo (+10% vs. D0, p < 0.01), confirmed by ultrasound examination. Furthermore, CsEx’s stimulation of fibroblasts, coupled with its antioxidant and energizing properties, led to a significant reduction in wrinkles by 28.0% (D28, p < 0.001). This study underscores Cordyceps sinensis hydroethanolic extract’s potential in regulating skin cell energy metabolism and positively influencing the mechanisms associated with skin longevity control.

Sweet corn (Zea mays L.) cultivars must meet stringent quality standards to be accepted in the marketplace. Breeding for eating-quality traits, such as sweetness, typically involves taste ratings or quantification of carbohydrate content. Total soluble solids (TSS) content is used as a proxy for sweetness in many fruit crops. Using a diallel of near-isogenic corn lines for sugary1, shrunken2, waxy1, and wild-type (WT) endosperm types, a combining ability analysis for carbohydrate traits and TSS content determined the relationship of these traits over three harvest dates. Variation existed for total sugar, sucrose, glucose, fructose, total polysaccharides, and starch content within and across endosperm types and harvest dates, but strong correlations with TSS content were present only when assessed across all endosperm types. Strong similarities existed among WT, waxy1, and sugary1 near-isogenic lines for general combining ability for carbohydrate traits, while shrunken2 near-isogenic lines had different desirable combiners. Line C40 was a desirable general combiner for carbohydrate traits among WT, waxy1, and sugary1 endosperm types, while Ia5125, P39, and Ia453 were desirable general combiners for shrunken2 endosperm. This experiment also determined that TSS content is not a useful trait in sweet corn breeding for quality traits.

The use of anthelminthic drugs has several drawbacks, including the selection of resistant parasite strains. Alternative avenues to mitigate the negative effects of helminth infection involve dietary interventions that might affect resistance and/or tolerance by improving host immunity, modulating the microbiota, or exerting direct anthelmintic effects. The aim of this study was to assess the impact of diet on strongyle infection in horses, specifically through immune-mediated, microbiota-mediated, or direct anthelmintic effects. Horses that were naturally infected with strongyles were fed either a high-fiber or high-starch diet, supplemented with either polyphenol-rich pellets (dehydrated sainfoin) or control pellets (sunflower and hay). When horses were fed a high-starch diet, they excreted more strongyle eggs. Adding sainfoin in the high-starch diet reduced egg excretion. Additionally, sainfoin decreased larval motility whatever the diet. Moreover, the high-starch diet led to a lower fecal bacterial diversity, structural differences in fecal microbiota, lower fecal pH, lower blood acetate, and lower hematocrit compared to the high-fiber diet. Circulating levels of Th1 and Th2 cytokines, lipopolysaccharides, procalcitonin, and white blood cells proportions did not differ between diets. Overall, this study highlights the role of dietary manipulations as an alternative strategy to mitigate the effect of helminth infection and suggests that, in addition to the direct effects, changes in the intestinal ecosystem are the possible underlying mechanism.

Blackcurrant is well known for its health benefits, but its wine products are understudied. In this research, studies were conducted after non-Saccharomyces and Saccharomyces yeast strain inoculation in less than 20% (w/v) fruit must for blackcurrant fermentation. Three inoculations were carried out on blackcurrant musts, as follows: (1) sequential inoculation with Torulaspora delbrueckii (strain Biodiva) followed by Saccharomyces EC1118 strain; (2) sequential inoculation with Metschnikowia pulcherimma (strain Flavia) followed by EC1118; (3) single-strain inoculation with EC1118 as the control treatment. None of these treatments did alter sugar consumption dynamics. Biodiva inoculation had impacts on both color dynamic parameter changes and final wine color profiles compared to EC1118. The final wine compositions indicate that Biodiva treatment had a significant impact on wine pH and acidity, whereas EC1118 single-strain largely influenced wine ethanol and glycerol contents. Although the total antioxidant capabilities were close among the three produced wines, the monophenol profiles indicate that Biodiva enhanced the total anthocyanin and hydroxycinnamates content but reduced the total flavanol contents in the final wine. EC1118 and Flavia wines contained more total flavanols compared to Biodiva treatment. The nonflavonoid profiles indicate that there were no significant differences among the three treatments. Our findings provide useful information for the application of yeast strains in blackcurrant wine fermentation.