Carbohydrate Analysis Research Articles

Elaboração de macarrão enriquecido com farinha de resíduos do camarão gigante da Malásia

Um dos grandes entraves das plantas processadoras de camarões é a geração de resíduos. Atualmente, as legislações ambientais por partes dos órgão reguladores, vem cobrando destinação adequadas destes resíduos das indústrias, minimizando os impactos ao ambiente. Os resíduos de camarão possuem uma grande quantidade de nutrientes, entre elas lipídeos e proteínas com potencial aproveitamento na alimentação animal e humana. Desta forma, objetivou-se elaborara um macarrão enriquecido nutricionalmente, através da inclusão de diferentes concentrações de farinha de resíduo de camarão Macrobrachium rosenbergii. O experimento foi conduzido em DIC com três tratamentos, inclusão (15, 20 e 25%) de farinha de resíduo, mais um controle, sem a inclusão. Foram realizadas análises sensoriais dos tratamentos para aparência, aroma, cor sabor, textura, aceitação geral, frequência de consumo, intenção de compra e índice de aceitação, realizados por 60 provadores não treinados e análises bromatológicas para umidade, cinzas, lipídeos, proteínas, carboidratos e valor calórico do produto elaborado. Indica-se a inclusão de resíduos de camarão acima de 20% para produção do macarrão, pois não houve diferença significativa (P>0,05) em relação ao tratamento com 25 %, que apresentou 20,51% de proteínas. Quanto à aceitação do produto, o tratamento com 0% de inclusão foi o que obteve melhor resultado com 77,22%, no entanto, apresenta o menor valor de proteínas 16,89%, e maior valor calórico 215,80 (kcal/100g). A inclusão de farinha de resíduos de M. rosenbergii na formulação de macarrão pode ser uma alternativa de destinação dos resíduos gerados, assim como, a agregação de valor deste recurso.

Flow Chemistry System for Carbohydrate Analysis by Rapid Labeling of Saccharides after Glycan Hydrolysis.

This study demonstrates the utilization of a flow chemistry system for continuous glycan hydrolysis and saccharide labeling to assist with the existing methods in glycan structural analysis. Acidic hydrolysis of glycans could be accelerated in a flow system. Aldoses and α-ketoacid-type saccharides were effectively labeled with naphthalene-2,3-diamine (NADA) at 60 °C for 10 min to form the fluorescent naphthimidazole (NAIM) and quinoxalinone (QXO) derivatives, respectively. The NADA-labeled derivatives improved the structural determination and composition analysis for their parent saccharides by using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), liquid chromatography mass spectrometry (LC-MS), and nuclear magnetic resonance (NMR). Furthermore, this protocol was applied to determine the SA–Gal–Glc sequence of GM3-sugar out of six possible permutations.

Driving Forces Analysis of Non-structural Carbohydrates for Phragmites australis in Different Habitats of Inland River Wetland

Habitat variation in non-structural carbohydrates (NSC) reflects the resource allocation trade-offs for clonal plants, and its driving force analysis embodies the ecological adaptation strategy of clonal plants to heterogeneous environments. In this paper, the reed (Phragmites australis) in the northwestern inland wetlands of China, as a typical example of clonal plants, was used as the research object. The content and distribution of NSC in reeds and their response characteristics to soil environmental factors were compared under three different environmental gradients with wet, salt marsh and desert habitats. The results showed: (1) the content of NSC and starch gradually increased and the content of soluble sugar gradually decreased from wetland to desert habitats, and the ratio of soluble sugar to starch increased significantly (p < 0.05), which demonstrated that reeds converted more NSC into starch to adapt to harsh environments as the environment changed. (2) Reeds tended to invest more NSC in underground architectures to achieve survival and growth with the increase in environmental stress, providing the evidence that NSC were transferred from leaf to rhizome, and root, stem and rhizome received more soluble sugar investment. The ratio of soluble sugar to starch of reed stem and rhizome increased significantly with the increasing content of soluble sugar and the decreasing content of starch, and more starch was converted into soluble sugar to resist the harsh environment. (3) Soil water, soil bulk density and salinity were the main driving forces for the NSC content and the distribution characteristics of reeds using the relative importance analysis. The study results clarified the habitat variation law, and the main environmental driving forces of NSC for reeds in inland river wetlands, which provided the significant references for enriching the ecology research theory of clonal plants and protection measures in the fragile and sensitive wetlands in arid regions.

Development, standardization, quality evaluation and shelf life studies of indigenous beverage – Jigarthanda

The paper elaborates the investigation carried out to determine and standardize traditional beverage Jigarthanda, indigenous to the state of Tamil Nadu in India, the beverage hails from Madurai district. The paper discusses about the formulating and selecting ingredient levels of almond gum, basil seeds and sherbet concentration for the preparation of Jigarthanda. The chemical attributes comprise of protein, fat, carbohydrate and ash content analysis. From the results of the study it was apparent that 50% almond gum and 5% basil seed, 25g Ice cream and 10 ml evaporated milk as good combination to combine and process a ready to consume Jigarthanda. Different flavours of sherbet like rose, nannari (Indian sarsaparilla) and pine apple was subjected to different concentration and added to the beverage. The combination of 50% almond gum, 5%basil seeds and 8% syrup showed the better overall acceptability and comestible than others. The beverage contained Protein in the range of 1.64 to 1.75%, Fat was 3.19 to 3.98%, 0.33 to 0.36% Ash, moisture content ranged between 0.83 to 0.84% and carbohydrate was 9.97% to 11.73%.

The application of DFRC method for the analysis of carbohydrates in a peat bog: Validation and comparison with conventional chemical and thermochemical degradation techniques

Traditional acid hydrolysis is the main method used for carbohydrates characterization in soils and sediments. It has been used to cleave the glycosidic bond, yielding monomers that compose polysaccharides of the non-cellulosic pool (free, ligno-cellulosic and hemicellulosic carbohydrates). In this study, the widely used chemical and thermochemical degradation procedures have been compared with the derivatisation followed by reductive cleavage (DFRC) method. This method presented efficiency in specifically cleaving the aryl ether bonds, yielding for sugar moieties linked to aromatic structures (ligno-cellulosic fraction). Once applied for peat samples, some discrepancies were observed. DFRC method revealed some information about the origin of carbohydrates that was hidden from the traditional chemical and thermochemical degradation methods. Several patterns of carbohydrates have been obtained with DFRC indicating difference in the origin and/or degradation rates between monosaccharides. For xylose, it showed an increase in the catotelm (deepest layer of the peatland), indicating an angiosperm vegetation input at the early stage of the peatland formation. Ribose, commonly known as a microbial indicator, showed the same profile as for hexoses and deoxyhexoses, with acid hydrolysis. The difference in the profile yielded in the case of DFRC method, revealed its microbial input. These information were hindered from acid hydrolysis and thermochemolysis, as the first showed nearly the same profile for all monosaccharides and the second one didn't have the capacity to analyze arabinose and ribose.Generally, higher similarity was obtained between DFRC and acid hydrolysis than between DFRC and thermochemolysis. This is due to the difference of mechanisms involved in chemolytic and thermochemolytic methods. For the first group, both methods shared acid conditions and milder temperature conditions if compared to the second group. In addition thermochemolysis is performed under alkaline conditions.

Determination of simple carbohydrates in beer using SPME, on fiber derivatization and gas chromatography mass spectrometry

Fermentable sugars directly contribute to the sweetness of beer, whereas carbohydrates with more than four glycosyl units can be beneficial to the perception of beer in that they contribute to body or mouthfeel. GC/MS has not been widely used for the analysis of carbohydrate contents in beer. The analysis of beer by using L-SPME, on fiber derivatization with bis(trimethylsilyl) trifluoroacetamide (BSTFA) and GC-MS showed the presence of some carbohydrates (D-arabinose, -D-arabinopyranose, D-galactose, Dxylose, and D-mannose) never detected in beer. The analysis of three different types of beer showed that the presence of these carbohydrates can represent a significant part of the total amount of carbohydrates present in the beer.

Unmasking the heterogeneity of carbohydrates in heartwood, sapwood, and bark of Eucalyptus

In this study, the cellulose and hemicelluloses in heartwood, sapwood, and bark of E. urophylla × E. grandis were comprehensively investigated. The ultrastructural topochemistry of carbohydrates in cell walls was examined in situ by confocal Raman microscopy. Cellulose and alkali-extractable hemicelluloses samples were isolated from different tissues and comparatively characterized by compositional carbohydrate analyses, determination of molecular weights, FT-IR spectroscopy, and XRD and NMR techniques. It was found that among all of the samples, heartwood cellulose had the highest molecular weight as well as the lowest degree of crystallinity. Meanwhile the hemicelluloses in heartwood had higher xylose content, lower degree of branching, slightly lower molecular weights but narrower polydispersity than those in sapwood. The eucalyptus hemicelluloses mainly consisted of (1→4)-β-D-xylan backbone with glucuronic acid side chains. Furthermore, the hemicelluloses isolated from sapwood had a higher degree of substitution with terminal galactose than those isolated from heartwood and bark.

SEASONAL VARIATION OF AMINOACIDS AND CARBOHYDRATES IN HAEMOLYMPH OF SPODOPTERA LITURA FABRICIUS (LEPIDOP TERA: NOCTUIDAE) FED WITH DIFFERENT HOST PLANTS

Spodoptera litura, an important polyphagous pest, causes serious threat to a large number of economically important crops all over the world. In the present study, the quantitative analysis of aminoacids and carbohydrates in haemolymph of the last instar larvae of Spodoptera litura fed with five different host plant leaves was carried out. A comparative study of the biochemical components in the selected host plant leaves was also carried out. The data obtained were statistically analysed using one-way ANOVA (P<0.01). The results revealed that there was a significant variation in the concentration of these biochemical components in haemolymph with respect to the feeding material and with seasonal variation.

Nutritional and Functional Potential of Selliera radicans Cav., a Chilean Native Halophyte

Background: Selliera radicans was recognized as one of the foods consumed by the oldest human settlement in America (Monte Verde, Chile) that had a diet with a high component of plants. Objective: This study aims at investigating nutritional and functional characteristics of S. radicans, a native halophyte from Chile. Materials and Methods: An analysis of total protein, carbohydrate, ash, and moisture from S. radicans leaves was performed, using standard methods. The content of macro and micronutrients was quantified by atomic absorption spectrometry. The inulin content was carried out based on the Seliwanoff reactions. S. radicans leaves were extracted with methanol and the total content of phenolic and flavonoids and antioxidant activity were evaluated by spectroscopic method. Results: Leaves from cultivated plants proved to be a suitable source of proteins (7.5 % on DW), ash (6.8 % on DW), and a wide range of macro and micronutrients, where Ca, K, and Na had the highest values. In addition, inulin (2.3% on DW), total phenolics (63.4 GAE/g LDW) and flavonoids (21.8 QE/g LDW), and antioxidant capacity (10 TE/g LDW) were noted. Conclusions: According to the results, cultivated S. radicans leaves are promising sources of food with beneficial health properties.

Effect of essential oils of Mentha spicata L. and Melaleuca alternifolia Cheel on the midgut of Podisus nigrispinus (Dallas) (Hemiptera: Pentatomidae)

Agricultural pest control is a popular research topic, and essential oils are widely studied because they represent a promising alternative to synthetic insecticides. However, despite the increase in studies on pests, little work has been done on pesticide contamination of the predators feeding on insecticide-affected prey. Therefore, the objective of this study was to evaluate the effects of Lethal Dose 50 (LD50) from the essential oils of Mentha spicata L. and Melaleuca alternifolia Cheel on the histology, including histochemistry (from protein and carbohydrate analysis) and immunohistochemistry (from the evaluation of cellular apoptosis), of the midgut of fifth instar nymphs of Podisus nigrispinus (stinkbug) (Dallas). The periods of analysis were 12, 24, and 48 h after ingestion of Alabama argillacea Hübner caterpillars treated with the respective oils. The oil from M. spicata did not cause histological alterations or apoptosis in the insect. However, there was a reduction in the level of carbohydrates within the 48-h period. After 24 h, the oil of M. alternifolia caused an elongation of digestive cells and, after 48 h, cell lysis with the release of material into the lumen, suggesting tissue necrosis. The immunohistochemical study revealed no apoptotic process. There was a reduction in the neutral carbohydrate levels in the 24- and 48-h periods and in the number of regenerative cells, when compared to the control, after the period of 48 h. These results demonstrate that M. spicata oil has potential for use in cotton fields because it does not affect the vital characteristics of P. nigrispinus. However, the essential oil of M. alternifolia is not suitable for use as a pesticide because it is extremely toxic to predators.

CCMRD: a solid-state NMR database for complex carbohydrates.

Carbohydrates are essential to various life activities in living organisms and serve as the central component in many biomaterials. As an emerging technique with steadily improving resolution, solid-state Nuclear Magnetic Resonance (NMR) spectroscopy has the unique capability in revealing the polymorphic structure and heterogeneous dynamics of insoluble complex carbohydrates. Here, we report the first solid-state NMR database for complex carbohydrates, Complex Carbohydrates Magnetic Resonance Database (CCMRD). This database currently holds the chemical shift information of more than four hundred solid-state NMR compounds and expects rapid expansion. CCMRD provides open portals for data deposition and supports search options based on NMR chemical shifts, carbohydrate names, and compound classes. With the timely implementation, this platform will facilitate spectral analysis and structure determination of carbohydrates and promote software development to benefit the research community. The database is freely accessible at www.ccmrd.org.

Spatial and Pregnancy-Related Changes in the Protein, Amino Acid, and Carbohydrate Composition of Bovine Oviduct Fluid.

Knowledge of how the biochemical composition of the bovine oviduct is altered due to the oviduct anatomy or the presence of an embryo is lacking. Thus, the aim of this study was to assess the effect of (І) oviduct anatomy and (ІІ) embryo presence on oviductal fluid (OF) protein, amino acid, and carbohydrate composition. Cross-bred beef heifers (n = 19) were synchronized and those in standing estrus were randomly allocated to a cyclic (non-bred) or pregnant (artificially inseminated) group. All heifers were slaughtered on Day 3 after estrus. The oviducts ipsilateral to the corpus luteum from each animal were isolated, straightened and cut, separating ampulla and isthmus. Each portion was flushed with 500 µl of PBS enabling recovery of the oocyte/embryo. Recovered unfertilized oocytes (cyclic group) and embryos (8-cell embryos; pregnant group) were located in the isthmus of the oviduct. Samples of flushing medium from the isthmus and ampulla were used for proteomic (n = 2 per group), amino acid (n = 5), and carbohydrate (n = 5) analysis. For proteomic analysis, total protein from cyclic and pregnant samples were labelled with different cyanine fluorescent probes and separated according to the isoelectric point using immobilized pH gradient strips (pH 3–10, 17 cm, Protean® IEF cell system, Bio Rad). Second dimension was performed in a polyacrylamide gel (12%) in the presence of SDS using a Protean II XL system (Bio Rad). Images were obtained with a Typhoon 9410 scanner and analyzed with Progenesis SameSpots software v 4.0. Amino acid content in the OF was determined by high performance liquid chromatography (HPLC). Glucose, lactate, and pyruvate were quantified using microfluorometric enzyme-linked assays. For the proteomic assessment, the results of the image analysis were compared by ANOVA. For both amino acid and carbohydrate analyses, statistical analysis was carried out by 2-way ANOVA with the Holm-Sidak nonparametric post hoc analysis. On Day 3 post-estrus, OF composition varied based on (І) anatomical region, where isthmic metabolites were present in lower (i.e., lactate, glycine, and alanine) or higher (i.e., arginine) concentrations compared to the ampulla; and (ІІ) embryo presence, which was correlated with greater, arginine, phosphoglycerate kinase 1, serum albumin, α-1-antiproteinase and IGL@ protein concentrations. In conclusion, data indicate that the composition of bovine OF is anatomically dynamic and influenced by the presence of an early embryo.

Proximate analysis of fruits and vegetables wastes from Nairobi County, Kenya

Proximate analysis of twenty fruits and vegetable waste from Nairobi County was evaluated. They were obtained from Kangemi and Wakulima markets. Standard procedures were used for the analysis of crude fat, protein, fiber, carbohydrates, moisture, ash, nitrogen-free extract and energy. The results obtained revealed that moisture content was in the range of 82.8 to 95.86% apart from sweet potato and banana which was 62.05 and 74.30% respectively. Protein range was between 0.57 to 3.49% with high-fat content being recorded in avocado at 9.03%. The ash content was highest in comfrey at 3.46% and lowest in mango at 0.44%. The carbohydrate level obtained by the difference method was lowest in courgette at 1.99% with crude fiber ranging from 0.69 to 2.73%. The total calculated energy ranged from 1.94 to 39.98 Kcal/100g. The macro-nutrient concentrations were 3.59 and 1.53% for potassium and calcium respectively. Lead, iron and zinc were detected at 15.1±3.6, 3742±235 and 176±11 ppm respectively. There is the presence of proximate properties in the edible portion of wasted fruits and vegetable and therefore, this study recommends proper fruits and vegetable handling during harvest, transportation, storage and marketing. Besides, the unavoidable waste should be used as biomass in energy production to deal with landfilling issues in the market places.

Nutritive value of ghee residue incorporated bakery product

The present study entitled “Nutritive value of ghee residue incorporated bakery product” was carried out with the objectives to utilize the Ghee residue for the preparation of bakery products. The products prepared were Cake and Muffins by utilization of Ghee residue incorporated in different proportions and served as treatments T 1, T 2 ,T 3 and T 4 respectively. T 0 , without incorporation of utilization of Ghee residue , served as control. Chemical analysis of carbohydrate, protein, energy, calcium was done by AOAC (2005) methods. Sensory evaluation was carried out using the nine-point Hedonic scale. The nutritive value of the prepared products was determined using food composition tables (Gopalan et al ., 2011) and the values obtained from the analysis of prepared products. Data obtained were statistically analysed by using analysis of variance (ANOVA), (t) test and critical difference (CD) techniques. On the basis of findings, it was observed that in case of Cake 60 percent refined flour and 40 percent ghee residue incorporation level scored the best with regard to colour, body and texture, taste and flavour and overall acceptability. In muffins 60 percent refined flour and 40 percent ghee residue incorporation level scored the best with regard to colour, body and texture, taste and flavour and overall acceptability. Four replications of control and treatments for all two products were carried out and mean values were obtained. Utilization of Ghee residue for the preparation of bakery products like Cake, Muffins were well acceptable, based on sensory evaluation . In Cake T 4 (wheat flour refined + Ghee residue in the ratio, 60:40) was the best. In Muffins T 4 (wheat flour refined + Ghee residue in the ratio, 60:40) was the best. The cake had maximum calcium(71.35mg/100g), Protein (23.48g/100g) and Fat (89.96g/100g) were increased as compared to control. In Muffins, Calcium (131.35mg/100g), Protein (56.48g/100g) and Fat(90.72g/100g) were increased as compared to control. Cost of the products on the basis of raw ingredients per 100g ranged between Rs 29.00 for Cake, Rs 31.00 for Muffins. It is concluded that Ghee residue can be incorporated in the preparation of different products in addition to improving the nutrient content.

A55 LACK OF EXPERIMENTAL REPRODUCIBILITY IN PRECLINICAL RESEARCH IS INFLUENCED BY THE NUTRITIONAL PROFILE OF STANDARD RODENT CHOWS

Abstract Background Lack of experimental reproducibility, particularly in studies investigating the microbiota, is of growing concern to the scientific community. Factors such as environment, stress, and sex have been identified as contributors, whereas dietary composition has received less attention. Aims To profile the use of standard rodent chows in research institutions, analyze the nutrient content of common rodent chows, and assess the impact of different chows on microbiota profiles. Methods A survey was conducted to evaluate which rodent chows are used by research institutions worldwide. Seven standard rodent chows were selected for analysis of ingredients, fermentable carbohydrate (FODMAP) and gluten content. FODMAP content was measured by high-performance liquid-chromatography and enzymatic assays, and gluten content was assessed by a commercial kit using G12 antibody. Forty C57BL/6 mice were randomized to 4 groups of 10 mice (5 male, 5 female). Group A was euthanized at baseline. Group B received the breeding institution chow (LabDiet 5066). Group C received ResearchDiets AIN93G (low FODMAP and gluten content). Group D received LabDiet 5001 (high FODMAP and gluten content). After 3 weeks, cecal contents were collected and analyzed by 16S rRNA gene sequencing; short- and branched-chain fatty acids (SCFA, BCFAs) content was also determined. Results Twenty-eight different types of rodent chows were reported to be used by 45 international survey respondents. Ingredient composition of the standard chows varied widely, resulting in differences in FODMAP and gluten content. Microbiota analysis of cecal contents revealed that gut microbiota composition was altered by the standard chows, as reflected by significantly different clusters in β-diversity analysis as well as by altered α-diversity. Microbiota diversity was also influenced by sex in Groups A and B (p<0.01). Total SCFA levels were lower (p=0.03) and BCFA levels were higher (p=0.01) in Group C compared to Group B. Conclusions Our results suggest that the composition of the diet not only significantly impacts gut microbiota profiles and fermentation patterns but may also emphasize sex differences in preclinical studies, with major implications for the reproducibility of results across laboratories. Funding Agencies CIHRThe Canadian Nutrition Society

The investigation of adaptogenic, hypoglycemic and hepatoprotective properties of Clitoria ternatea L. on experimental models in vivo

This work is devoted to the study of the effect of Clitoria ternatea L. decoction for energy and carbohydrate metabolism in conditions of increased physical activity, the analysis of possibilities carbohydrate and lipid metabolism markers correcting in a model of experimental hyperphagia and experimental diabetes, and the efficiency of the stabilization of liver injury and lipid peroxidation markers in rats in an experimental model of chronic alcohol intoxication. It’s established that Clitoria ternatea L. has a stabilizing effect on carbohydrate metabolism in rats with experimental diabetes and hyperphagia, exhibits antioxidant and hepatoprotective effect in rats with experimental alcoholic liver, comparable to the action of classical hepatoprotector «Hepsil-Rn», has adaptogenic effect in experimental model of physical activity, comparable to the energy drink «Burn». The effect of the prepatation tested was more pronounced under alloxan diabetes than the effect of the anti-diabetic «Sadifit» collection. The results obtained may be due to the presence of flavonoids, ascorbic acid, tannins and unsaturated fatty acids, exhibiting an antioxidant effect, as well as glycosides, terpenes and diterpenes, contributing to increased permeability of cell membranes for glucose.

Analysis of Non-Structural Carbohydrates and Xylem Anatomy of Leaf Petioles Offers New Insights in the Drought Response of Two Grapevine Cultivars.

In grapevine, the anatomy of xylem conduits and the non-structural carbohydrates (NSCs) content of the associated living parenchyma are expected to influence water transport under water limitation. In fact, both NSC and xylem features play a role in plant recovery from drought stress. We evaluated these traits in petioles of Cabernet Sauvignon (CS) and Syrah (SY) cultivars during water stress (WS) and recovery. In CS, the stress response was associated to NSC consumption, supporting the hypothesis that starch mobilization is related to an increased supply of maltose and sucrose, putatively involved in drought stress responses at the xylem level. In contrast, in SY, the WS-induced increase in the latter soluble NSCs was maintained even 2 days after re-watering, suggesting a different pattern of utilization of NSC resources. Interestingly, the anatomical analysis revealed that conduits are constitutively wider in SY in well-watered (WW) plants, and that water stress led to the production of narrower conduits only in this cultivar.

Does pre-culture in sugar-rich media affect carbohydrate content and post-thawing recovery rate of cryopreserved potato (Solanum phureja) shoot tips?

Shoot tips of Potato (Solanum phureja) were cryopreserved with the encapsulation-dehydration method, including: coating of shoot tips in calcium alginate beads, pre-culture in a solution containing 0.75 M of sugar (0.1 M of sucrose +0.65 M of another cryoprotectant sugar), and dehydration (for 4.5 h) on silica gel to reduce water content to 21–27%. Regrowth of shoot tips was assessed after freezing in liquid nitrogen. After cryopreservation, coated shoot tips were cultivated on a medium enriched with growth substances to measure concentrations of soluble carbohydrates. Maltose and trehalose ensured a better cryopreservation (88% and 91% of regrowth, respectively). Regrowth rates of potato shoot tips in the presence of polyols were very low and no recovery was obtained after freezing of shoot tips that were pre-cultivated in monosaccharides. Concentration of soluble carbohydrates increased in shoot tips pre-cultivated in sucrose, trehalose or glucose, especially when sucrose was applied as the cryoprotectant. The application of sucrose helped potato shoot-tips to acquire a certain tolerance to dehydration and cryofreezing. The analysis of soluble carbohydrates in potato shoot tips confirmed the accumulation of sugars during the pre-culture process, principally in the form of sucrose. The statistical analysis showed that soluble carbohydrate contents in shoot tips increased when total carbohydrates increased in the cultivation medium. The modelling approach indicated that the contents of soluble carbohydrates increased when pre-cultivation of potato shoot-tips was conducted in sucrose media compared to the control and other sugars.

The Importance of Verification Practicum before Projet Based Practicum based on Local Material in Science Education

Practical activities cannot be separated from science education. Various kinds of practical models have been developed in science education. This research was conducted to see the importance of the verification practicum carried out before the project-based practicum with local material. Implementation of research using a mixed method with embedded design. The effectiveness of the program is measured by pre-post test design. Topics implementation were done on a qualitative analysis of protein, a qualitative analysis of lipids and a quantitative analysis of proteins for verification practicum. Topics were done on a quantitative analysis of proteins, carbohydrates qualitative analysis, quantitative analysis of carbohydrates and enzyme kinetics for laboratorium project based local material. The research instrument is a matter of pre-tests and post-tests that use creative thinking skills tests in the form of a description. Quantitative data analysis performed using SPSS 22.0 to see the significance of normality, the value of N-Gain. Qualitative data analysis is done through a questionnaire scale attitude. The results of the study showed that the verification practicum that was carried out before the project-based practicum with local materials had made students prepare themselves to be ready to do practical activities.

Computer-Assisted 3D Structure Elucidation (CASE-3D): The Structural Value of 2 JCH in Addition to 3 JCH Coupling Constants.

We present a method to use long-range CH coupling constants to derive the correct diastereoisomer from the molecular constitution of small molecules. A set of 79 2 JCH and 3 JCH values collected from a single HSQMBC experiment on a sample of strychnine were used in the CASE-3D (computer-assisted 3D structure elucidation) protocol. In addition to the most commonly used 3 JCH coupling constants, the subset of 32 2 JCH values alone showed an excellent degree of configuration selection. The study is mainly based on comparison of DFT-calculated 2,3 JCH values with experimental ones, critical for the case of 2 JCH . But the configuration selection also works well using 3 JCH values predicted from a semi-empirical Karplus-based equation limited to H-C-C-C fragments. The robustness, shown using strychnine as a proof of concept, makes the J-based CASE-3D analysis a viable option for the application in fields such as peptide and carbohydrate research, organic synthesis, natural-product identification and analysis, as well as medicinal chemistry.