Characterizing Individual Differences in Sweet Taste Hedonics: Test Methods, Locations, and Stimuli

Sweetness drives the consumption of added sugars, so understanding how to best measure sweet hedonics is important for developing strategies to lower sugar intake. However, methods to assess hedonic response to sweetness vary, making results across studies difficult to integrate. We compared methods to measure optimal sucrose concentration in 21 healthy adults (1) using paired-comparison preference tracking vs. ratings of liking, (2) with participants in the laboratory vs. at home, and (3) using aqueous solutions vs. vanilla milk. Tests were replicated on separate days to assess test-retest reliability. Test-retest reliability was similar between laboratory and home testing, but tended to be better for vanilla milk and preference tracking. Optimal sucrose concentration was virtually identical between laboratory and home, slightly lower when estimated via preference tracking, and about 50% lower in vanilla milk. However, optimal sucrose concentration correlated strongly between methods, locations, and stimuli. More than 50% of the variability in optimal sucrose concentration could be attributed to consistent differences among individuals, while much less variability was attributable to differences between methods. These results demonstrate convergent validity between methods, support testing at home, and suggest that aqueous solutions can be useful proxies for some commonly consumed beverages for measuring individual differences.

Spontaneous Regeneration of Plantlets Derived from Hairy Root Cultures of Lopezia racemosa and the Cytotoxic Activity of Their Organic Extracts

A histological analysis was performed with the aim of elucidating the spontaneous regeneration process of the hairy root lines LRT 2.3 and LRT 6.4, derived from Lopezia racemosa leaf explants and genetically transformed with the Agrobacterium rhizogenes strain ATCC15834/pTDT. The analysis showed both lines regenerate via indirect somatic embryogenesis; LRT 6.4 also regenerated by direct organogenesis. The morphogenic characteristics of the regenerated plantlets from both lines showed the typical characteristics, described previously, including a higher number of axillary shoot formation, short internodes, and plagiotropic roots compared with wild-type seedlings. The regeneration process occurred without the addition of plant growth regulators and was linked to the sucrose concentration in the culture medium. Reducing the sucrose concentration from 3% to 2%, 1%, and 0.5% increased the regeneration rate in LRT 6.4; the effect was less pronounced in LRT 2.3. The cytotoxic activity of different organic extracts obtained from roots and shoots were evaluated in the cancer cell lines HeLa (cervical carcinoma), HCT-15 (colon adenocarcinoma), and OVCAR (ovary carcinoma). The hexane and dichloromethane extracts from roots of both lines showed cytotoxic activity against the HeLa cell line. Only the dichloromethane extract from the roots of PLRT 2.3 showed cytotoxic activity against the OVCAR cell line. None of the methanol extracts showed cytotoxic activity, nor the shoot extracts from any solvent.

Competitive Biosynthesis of Bacterial Alginate Using Azotobacter vinelandii 12 for Tissue Engineering Applications

This study investigated the effect of various cultivation conditions (sucrose/phosphate concentrations, aeration level) on alginate biosynthesis using the bacterial producing strain Azotobacter vinelandii 12 by the full factorial design (FFD) method and physicochemical properties (e.g., rheological properties) of the produced bacterial alginate. We demonstrated experimentally the applicability of bacterial alginate for tissue engineering (the cytotoxicity testing using mesenchymal stem cells (MSCs)). The isolated synthesis of high molecular weight (Mw) capsular alginate with a high level of acetylation (25%) was achieved by FFD method under a low sucrose concentration, an increased phosphate concentration, and a high aeration level. Testing the viscoelastic properties and cytotoxicity showed that bacterial alginate with a maximal Mw (574 kDa) formed the densest hydrogels (which demonstrated relatively low cytotoxicity for MSCs in contrast to bacterial alginate with low Mw). The obtained data have shown promising prospects in controlled biosynthesis of bacterial alginate with different physicochemical characteristics for various biomedical applications including tissue engineering.

Changes in Structural and Rheological Properties of Guar Gum Particles in Fluidized-Bed Agglomeration: Effect of Sucrose Binder Concentration

Fluidized-bed agglomeration (FBA) is known to modify the structure and rheology of food powders. In this study, guar gum (GG) powders with various concentrations of sucrose binder (0%, 10%, 20%, or 30%) were subjected to fluidized-bed agglomeration. Subsequently, changes in the characteristics of the GG powders were evaluated by using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), particle size distribution (PSD) analysis, and rheological and dispersibility measurements. SEM images and FTIR spectra revealed surface morphology changes and structural modification, respectively, in the original GG powder after FBA, although the changes observed in FTIR spectra were only slightly dependent on sucrose concentration at low concentrations (0–20%). XRD patterns confirmed that the crystallinity of the GG powder was affected by FBA, but not greatly so by binder concentration. The PSD results showed that the GG particle size was increased by FBA and there was a clear relationship between sucrose concentration (10–30%) and mean particle size. The rheological behavior and dispersibility of GG (properties that are known to be affected by the structure of a powder) were also influenced by sucrose concentration. To sum up, FBA and the concentration of sucrose binder used can serve as factors for modifying GG powder.

Zinc sulphate or zinc nanoparticle applications to leaves of green beans

The green bean (Phaseolus vulgaris L.) is a very widely grown food crop that contributes significantly to human dietary needs in many countries due to its high content of protein. This study evaluates foliar applications of ZnSO4 versus that of zinc oxide nanoparticles (ZnO NPs) to leaves of the green bean cv. ‘Strike’ and records the plant responses in terms of Zn uptake and concentrations of photosynthetic pigments and bioactive compounds. The experiment was conducted under greenhouse conditions in Chihuahua, Mexico, with a completely randomised experimental design with 10 replicates. The two treatments were foliar applications of either an aqueous solution of ZnSO4 or an aqueous suspension of ZnO NPs (both 150 mg · L−1). The application of ZnO NPs significantly increased concentrations of Zn2+ in the leaflets, roots, stems and pods of chlorophylls a and b (values 15.40 μg · g−1 and 11.64 μg · g−1, respectively). Sucrose concentration was also increased by Zn2+ applications, but no differences were found in total phenols (TP), total flavonoids (TFl) or antioxidant capacity (AC). In the pods and seeds, Zn2+ application left sucrose and TFl concentrations unchanged, but the TP increase was significant. The AC was affected by both zinc sources and only in the pods. The applications of ZnSO4 or ZnO NPs significantly increased the biomass accumulation (79.10 g · p−1 and 84.70 g · p−1 DW) and yield (55.64 g · p−1 and 53.80 g · p−1 FW). These results suggest that the application of ZnO NPs could represent a worthwhile biofortification strategy in the commercial production of green bean cv. ‘Strike’.

Optimization of the enzymatic synthesis of fructo-oligosaccharides using fructosyltransferase from aspergillus aculeatus

The obvious benefits of employing prebiotics as functional components in many food and feed products have resulted in higher demand for their industrial production, necessitating the development of more efficient and cost-effective manufacturing procedures. As a result, the goal of this study was to synthesize confirmed prebiotics, namely fructo-oligosaccharides (FOS), using sucrose as a substrate, since it allows the synthesis of oligosaccharides with lower polymerization degree, and consequently, a more pronounced prebiotic effect. Due to its availability, low market price, and high stability under industrial conditions, a commercial enzymatic mixture, Pectinex® Ultra SP-L, is used as a source of enzyme – fructosyltransferase (FTase). By optimizing reaction conditions such as pH, temperature, enzyme and substrate concentrations, as well as the duration of the process, the composition of the FOS mixture can be adjusted to fit the potential applications. It was found that by performing the reaction in an aqueous medium (pH 7), at a temperature of 50 °C using an enzyme concentration of 1% (v/v) and any sucrose concentration in the range of 200-700 g/L, it was possible to achieve maximum FOS yield of 60% of total carbohydrates within a 24 h. The produced syrup with a high content of FOS can be further used as an adequate food additive, or else, optimized proceses should be used for transformation of various food products (such as juices, jams, fillings, candies, cakes, etc.) in which sucrose dominates, creating products with lower caloric and higher functional value.

Characterizing Individual Differences in Sweet Taste Hedonics: Test Methods, Locations, and Stimuli

Sweetness drives consumption of added sugars, so understanding how individuals differ is important for developing strategies to lower sugar intake. However, methods to assess hedonic response to sweetness vary, making results across studies difficult to integrate. We compared methods to measure optimal sucrose concentration in 21 healthy adults (1) using paired-comparison preference tracking vs. ratings of liking, (2) with participants in the laboratory vs. at home, and (3) using aqueous solutions vs. vanilla milk. Tests were replicated on separate days to assess test-retest reliability. Test-retest reliability was similar between laboratory and home testing, but tended to be better for vanilla milk and preference tracking. Optimal sucrose concentration was virtually identical between laboratory and home, slightly lower when estimated via preference tracking, and about 50% lower in vanilla milk. However, individual optimal sucrose concentration correlated strongly between Methods, test Locations, and Stimuli. More than 50% of the variability in optimal sucrose concentration could be attributed to consistent differences among individuals while much less variability was attributable to differences in Methods, test Locations or Stimuli. These results demonstrate convergent validity between measures of preference and liking, support testing at home to lower participant burden, and suggest that aqueous solutions can be useful proxies for some commonly consumed beverages for measuring individual differences.

RESEARCH OF AMYLOLYTIC ACTIVITY OF CULTURAL LIQUIDS IN BIOTECHNOLOGY OF SYMBIOTIC CROPS МЕDUSOMYCES GISEVII AND ORYZAMYCES INDICI

Based on the literature review found that the natural symbionts Medusomyces gisevii and Oryzamyces indici biotechnology are a valuable objects. It is urgent to find ways to impact on it in order to obtain these or other products of its life activity. At present, it is urgent to search for microorganisms producing enzymes, including amylase. One of the most promising in terms of biological objects is a natural microbial symbiont Medusomyces Gisevii (tea fungus) and Oryzamyces Indici, which, thanks to the not identical, microbiological composition and different growing conditions may have a different composition of metabolites. Studies of the amylolytic activity of the culture liquid Medusomyces Gisevii and Oryzamyces indici with different cultivation periods have been carried out. Cultivation of the fungus was carried out in the laboratory according to the classic method. The optimal concentration of sucrose for Medusomyces Gisevii and Oryzamyces Indici biomass growth was set at 5%. Sucrose concentration of 15% and above is not recommended for use due to inhibition of biomass growth with increasing concentration of carbohydrates in the culture medium. It is established that these symbionts start to show the amylolytic activity already on the 10th day of cultivation cultivation in standard nutrient medium, medium supplemented with 10 % milk and serum-based medium and stores it in the course of the experiment (30 days). Over time the amylolytic activity increases. However, the intensity of metabolism of the microorganisms, the criterion of which is the ratio of the total and exogenous amylase is most pronounced in the early stages of cultivation. It was found that the culture medium of polycultures shows high amylolytic activity. This fact allows us to consider the Medusomyces Gisevii and Oryzamyces Indici inoculum as a promising biotechnological raw material source of amylase enzyme.

Identification and Evaluation of Factors Affecting Nectar Volume and Concentrations of Croton Macrostachyus Hochst.ex Delile

Background: Secretion of nectar is highly influenced by many factors and the objective of the study was also to evaluate factors affecting concentrations of nectar of Croton macrostachyus Hochst.ex Delile. Age of plants highly affect nectar concentration and volume. Honey quality and its medicinal values depends on plants species variety and their sucrose concentration quality and quantity which is governed by many biotic and abiotic factors as well micro climate of the area. Wholesale of nectar and concentration of tend to show more differences in time of day for species study undertaken.Results: As results publicized that nectar concentration and volume of youngest age was not more affected by temperature and relative humidity like that of medium and oldest ages. Temperature and age have significant effect on volume (p = 0.0001) and their interactions is also significant (p = 0.01145). Temperature has significant effects on nectar concentration (p = 0.000). Interaction of relative humidity, time, and layers has significant effects on nectar concentration (p = 0.0024012). The oldest plants had the highest concentration of 10.1 w/w mornings and afternoon 36.5 w/w at 4:00 PM for whereas medium plants had nectar concentration of 5.7 w/w morning and afternoon 16.7 w/w and the smaller or younger plants had nectar concentration of 2.7 w/w mornings and afternoon 9.1 w/w and this shows age significantly affect nectar concentration and volume.Conclusions:Concentration and volume were affected by many biotic and abiotic factors. I conclude imminent fever intensification could harm nectar production since for croton also no nectar could be collected at 30 C⁰ and no nectar recreation was observed after this peak temperature this indicates environmental change can increase the temperature which will have negative influences on honey production in the future unless we combat against climate change which will affect honey production and productivity for the country and we will lose honey and its medicinal values also.

Foliar herbivory increases sucrose concentration in bracteal extrafloral nectar of cotton

Cultivated cotton, such as Gossypium hirsutum L., produces extrafloral (EF) nectar on leaves (foliar) and reproductive structures (bracteal) as an indirect anti-herbivore defense. In exchange for this carbohydrate-rich substance, predatory insects such as ants protect the plant against herbivorous insects. Some EF nectar-bearing plants respond to herbivory by increasing EF nectar production. For instance, herbivore-free G. hirsutum produces more bracteal than foliar EF nectar, but increases its foliar EF nectar production in response to herbivory. This study is the first to test for systemically induced changes to the carbohydrate composition of bracteal EF nectar in response to foliar herbivory on G. hirsutum. We found that foliar herbivory significantly increased the sucrose content of bracteal EF nectar while glucose and fructose remained unchanged. Sucrose content is known to influence ant foraging behavior and previous studies of an herbivore-induced increase to EF nectar caloric content found that it led to increased ant activity on the plant. As a follow-up to our finding, ant recruitment to mock EF nectar solutions that varied in sucrose content was tested in the field. The ants did not exhibit any preference for either solution, potentially because sucrose is a minor carbohydrate component in G. hirsutum EF nectar: total sugar content was not significantly affected by the increase in sucrose. Nonetheless, our findings raise new questions about cotton’s inducible EF nectar responses to herbivory. Further research is needed to determine whether an herbivore-induced increase in sucrose content is typical of Gossypium spp., and whether it constitutes a corollary of systemic sucrose induction, or a potentially adaptive mechanism which enhances ant attraction to the plant