Comparison Of Sugar Research Articles

Comparison of sugars, organic acids and aroma components of five table grapes in Xinjiang

The sugar, organic acid and aroma Components are very important quality characteristics of fruits. In this study, sugars, organic acids and volatile substances in five varieties of Xinjiang table grape pulp were determined by high-performance liquid chromatography and gas chromatography-mass spectrometry. The results showed that among the five varieties of table grapes in Xinjiang, fructose and glucose were the main sugars, accounting for 46.53-48.82% and 49.35-51.49% of the total sugar content, respectively. Tartaric acid and malic acid were the main organic acids, accounting for 55.72-60.07% and 28.54-39.52% of the total organic acids, respectively. The composition of sugars and organic acids ratio plays a significant role in the taste of table grapes. The sweetness of Red Globe was the highest while the acidity of Centennial Seedless was the highest. In addition, 87 varieties of volatile compounds were identified in table grape pulp with aldehydes as the major compounds (30.93-71.83%). In particular, trans-2-hexenal accounted for 19.33-44.56% of the total volatiles. Analysis of active odorants showed that nerol, geraniol, (Z)-3-hexenal, trans-2-hexenal, phenylacetaldehyde, citral and β-myrcene had great contributions to the flavors of Centennial Seedless and Muscat Hamburg, providing flowery, fruity, green and grassy flavors. Hexanol, trans-2-hexen-1-ol, damascone and ethyl butyrate had great contributions to the flavors of Rizamat, providing flowery, green and fruity flavors. Nonanal and 1-octen-3-one had great contributions to the flavors of Manaizi, providing mushroom and fruity flavors. The results provided the complete chemical characteristics of sugar, organic acids and volatile compounds of five varieties of table grapes in Xinjiang, China.

Comparison of sugars, lipids and phenolics content in the grains of organically and conventionally grown soybean in Serbia

Comparison of sugars, lipids and phenolics content in the grains of organically and conventionally grown soybean in Serbia

Profiles of Sugar and Organic Acid of Fruit Juices: A Comparative Study and Implication for Authentication

A comparison of sugar and organic acid profiles among different fruit juices (including apple, pear, peach, grape, sweet cherry, strawberry, and blueberry with various varieties) was performed to assess the possibility for authentication coupled with chemometrics. It was found that the distribution of each sugar and organic acid in juices showed some specific characteristics related to fruit species, despite the fact that great differences in the content existed among different varieties. Sucrose was the most abundant sugar in peach juice, accounting for 58.26–77.11% of the total sugar content. However, in grape, blueberry, and sweet cherry juice, glucose and fructose were the predominant sugars. Pear juice contained the highest level of sorbitol, which contributed to 15.02–43.07% of the total sugar content. Tartaric acid was detected only in grape juice among the seven species of fruit juice, with a proportion of 57.95–89.68% in the total acid content. Malic acid was the predominant organic acid in apple and sweet cherry juice, accounting for 69.92–88.30% and 97.51–98.73% of the total acid content of each species. Citric acid was the predominant organic acid in strawberry and blueberry juice, which contributed to 62.39–83.73% and 73.36–89.56% of the total acid content of each species. With the aid of principal component analysis and linear discriminant analysis (LDA), the juice samples could be successfully classified according to fruit species by using the sugar and/or organic acid composition as analytical data. Combination of sugar and organic acid composition gave the best differentiation of these seven species of juices, with a 100% correct classification rate for both the original and the cross-validation method in LDA. Adding malic/citric into the dataset of the organic acid content may also improve the differentiation effect. Furthermore, the adulteration of sweet cherry juice, blueberry juice, raspberry juice, and grape juice with apple juice, pear juice, or peach juice could also be distinguished from their corresponding pure juices based on sugar and organic acid composition by LDA.

Sugar and phenolics level dependent on the position of apple fruitlet in the cluster

The abscission process and the modifications in the levels of selected metabolites were monitored on ‘Golden Delicious’ apples in a two-year study. Individual sugars were analyzed using HPLC-RI and individual phenolics by UHPLC–PDA–MS. Fruitlets from lowest positions were most likely to shed. Moreover, fruits from the position nearest to the king fruitlet often dropped. The experiment initially focused on the comparison of sugar and phenolic contents among fruitlets within individual apple clusters. Central (king) fruitlets are bigger in comparison to lateral fruitlets and differ to a certain degree in the contents of metabolites. In general, the results indicate that phenolic contents are higher in fruitlets more susceptible to abscission but the level of sugars does not differ.

Comparison of Sugar and Honey Dressings in Healing of Chronic Wounds

Honey and Sugar dressings were applied to long standing surgical wounds in two groups comprising 25 patients in each matched for age and comorbidities.Dressings were done once in 3 days .Patients in sugar dressing group had faster healing rate, shorter hospital stay with rapid slough and microbial clearance. Sugar dressing also proved to be cost effective with decreased debridement frequency at the end of the study.

Role of cosolutes in gelation of high-methoxy pectin. Part 1. Comparison of sugars and polyols

Mixtures of high-methoxy pectin (DE 70; 1.0 wt%; pH 3.0) with ethan-1,2-diol, glycerol, xylitol, sorbitol, glucose, fructose or sucrose at concentrations of 50, 55, 60 and 65 wt% were prepared at 95 °C and changes in storage modulus ( G′) and loss modulus ( G″) during cooling to 5 °C, heating to 90 °C and re-cooling to 5 °C (at 1 °C/min) were measured at 1 rad s −1 and 0.5% strain. In all cases, the onset temperature for gelation during cooling and the moduli recorded at 5 °C increased with increasing concentration of cosolute. Both values, however, were substantially lower for the liquid cosolutes (ethan-1,2-diol and glycerol) than for mixtures incorporating the same concentrations of the solid cosolutes. The difference is attributed to inhibition of pectin–pectin interactions by pectin–cosolute interactions, which in turn are inhibited by cosolute–cosolute interactions, these being weaker for the liquid cosolutes than for the solids (as indicated by lower melting points). On heating, there was an initial reduction in modulus, with the same temperature-course as the increase on cooling; for the solid cosolutes, this was followed by an increase attributable to hydrophobic association of methyl ester substituents. No such increase was seen with the liquid cosolutes, but differential scanning calorimetry studies showed two (reversible) thermal transitions in all cases, one over the temperature-range of the initial gelation process on cooling and the other coincident with the increase in modulus on heating in the presence of the solid cosolutes. The absence of any detectable increase in modulus on heating with the liquid cosolutes is attributed to accumulation of cosolute around the polymer chains (i.e. pectin–cosolute interactions) promoting hydrophobic association between methyl ester groups on the same chain, or within small clusters of chains, with, therefore, no contribution to network structure. At high concentrations of the solid cosolutes, the increase in modulus on heating was followed by a decrease at higher temperature; this is attributed to excessive aggregation, and was reflected in lower moduli on subsequent re-cooling to 5 °C, in contrast to the enhancement in gel strength after heating and cooling that was observed at lower concentrations of the same cosolutes.

The NMR structure of [Xd(C2)]4 investigated by molecular dynamics simulations

AbstractThe i‐motif tetrameric structure is built up from two parallel duplexes intercalated in a head‐to‐tail orientation, and held together by hemiprotonated cytosine pairs. Two topologies exist for the i‐motif structure, one with outermost 3′ extremities and the other with outermost 5′ extremities, called the 3′E and 5′E topology, respectively. Since the comparison of sugar and phosphate group interactions between the two topologies is independent of the length of the intercalation motif, the relative stability of the 3′E and 5′E topologies therefore should not depend on this length. Nevertheless, it has been shown that the 3′E topology of the [d(C2)]4 is much more stable than the 5′E topology, and that the former is the only species observed in solution. In order to understand the reason for this atypical behavior, the NMR structure of the [Xd(C2)]4 was determined and analyzed by molecular dynamics simulations. In the NMR structure, the width of the narrow groove is slightly smaller than in previously determined i‐motif structures, which supports the importance of phosphodiester backbone interactions in the structure stability. The simulations show that the stacking of cytosines, essential for the i‐motif stability, is produced by a similar and non‐negative twisting of the phosphodiester backbones. The twisting is induced by an interaction between the backbones; the [Xd(C2)]4 in 5′E topology, exhibiting very limited interaction between the phosphodiester backbones, is thus unstable. Copyright © 2002 John Wiley & Sons, Ltd.

Accumulation of aluminium in the cell wall pectin in cultured tobacco (Nicotiana tabacum L.) cells treated with a combination of aluminium and iron

ABSTRACTIn nutrient medium, aluminium (Al) accumulation in tobacco cells occurs only in the presence of ferrous ion [Fe(II)]. The localization of Al was examined to elucidate a mechanism of Al accumulation. After the digestion of Al‐treated cells with cellulase and pectolyase together, the resulting spheroplasts contained as much Al as the intact cells. However, the cell walls isolated from Al‐treated cells also contained as much Al as the intact cells. Comparison of sugar and Al contents in polysaccharide components extracted chemically from cell walls isolated from intact cells and spheroplasts revealed that the enzymes digested most of the cellulose and hemicellulose, but only half of the pectin, and that Al mainly existed in the pectin remaining in the spheroplasts. Gel‐permeation chromatography of the pectin fraction (NH4‐oxalate extract) from the cell walls of the intact cells indicated that Al was associated with small polysaccharides of approximately 3–7 kDa. These results suggest that a minor part of pectin is a major site of Al accumulation. The content of cell wall pectin increased during Al treatment in nutrient medium. Taken together, we hypothesize that Al may bind to the pectin newly produced during Al treatment.