Analytical Standard Methods Research Articles

DEVELOPMENT OF ENRICHED CUPCAKES AND COOKIES WITH ORANGE-FLESHED SWEET POTATO (IPOMEABATATAS L.): SENSORY AND NUTRITIONAL EVALUATION

In developing countries especially in Côte d’Ivoire child malnutrition is a major burden. This malnutrition is often associated with poor nutritional composition of the complementary foods introduced during the weaning period. The purpose of this study was to assess nutritional, microbiological, and sensory properties of cupcakes and cookies supplemented with orange-fleshed sweet potato (OFSP). The proximate and microbiological analysis of enriched products was performed using analytical standard methods. Sensory evaluation of formulated cupcakes and cookies was based on nine-point hedonic scales. Proximate composition showed significant improvements in the contents of ash (1.02±0.06 – 1.98±0.03 g/100g dw), fiber (5.39±0.13 – 7.64±0.47 g/100g dw), and provitamin A (1031 – 4641 mg/100g dw) of enriched cupcakes and cookies compared to control. Based on moderate daily consumption of two pieces of OFSP composite cupcakes (60g/piece) and cookies (44g/piece), children aged 1 to 3 years may cover at least 42 and 85 % of their RDA for vitamin A, respectively. The microbial analysis indicated showed that enriched OFSP cupcakes and cookies were of acceptable microbiological quality. In addition, the enriched OFSP cupcakes and cookies were accepted and liked by the consumers excepted those containing 50% OFSP flour. Thus, cupcakes and cookies formulated with 35% OFSP flour can serve as a valuable vehicle for improving the nutritional status of young children.

Chemical, Thermal and Antioxidant Properties of Lignins Solubilized during Soda/AQ Pulping of Orange and Olive Tree Pruning Residues.

Some agroforestry residues such as orange and olive tree pruning have been extensively evaluated for their valorization due to its high carbohydrates content. However, lignin-enriched residues generated during carbohydrates valorization are normally incinerated to produce energy. In order to find alternative high added-value applications for these lignins, a depth characterization of them is required. In this study, lignins isolated from the black liquors produced during soda/anthraquinone (soda/AQ) pulping of orange and olive tree pruning residues were analyzed by analytical standard methods and Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (solid state 13C NMR and 2D NMR) and size exclusion chromatography (SEC). Thermal analysis (thermogravimetric analysis (TGA), differential scanning calorimetry (DSC)) and antioxidant capacity (Trolox equivalent antioxidant capacity) were also evaluated. Both lignins showed a high OH phenolic content as consequence of a wide breakdown of β-aryl ether linkages. This extensive degradation yielded lignins with low molecular weights and polydispersity values. Moreover, both lignins exhibited an enrichment of syringyl units together with different native as well as soda/AQ lignin derived units. Based on these chemical properties, orange and olive lignins showed relatively high thermal stability and good antioxidant activities. These results make them potential additives to enhance the thermo-oxidation stability of synthetic polymers.

Assessment on the Physicochemical and Phytochemical Properties, Nutritional and Heavy Metal Contents, and Antioxidant Activities of Hylocereus polyrhizus Peel from Northern Philippines

Background/Objectives: In the Philippines, Hylocereus polyrhizus is gaining upsurge interest due to its potential health benefits. Aside from the edible fruit pulp, various products from its peel are being developed, and claimed as health boosters. Thus, this study was conducted to assess the physicochemical characteristics, phytochemical constituents, nutritional and heavy metal contents and antioxidant activity of the peel of H. polyrhizus. Methods/Statistical analysis: Physicochemical and phytochemical screening were conducted following established protocols. Nutritional value and trace metals were measured with food analytical standard methods. Antioxidant activity was estimated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing capacity (FRC) assays. Statistical analyses were carried out for DPPH and FRC assays using Graph-Pad Prism. Findings: Results showed that H. polyrhizus peel contains alkaloids, coumarins, flavonoids, phenols, and triterpenoids. Trace amounts of arsenic (0.022 mg/kg), lead (0.887 mg/kg), cadmium (0.068 mg/kg) and chromium (0.225 mg/kg) were detected which were all within the acceptable limit set by the WHO for herbal materials. H. polyrhizus peel contained 6.72% moisture, 14.7% ash, 0.526% total fat, 0.226% saturated fat, 3.73% total sugar, 4.28% crude protein, 73.8% total carbohydrate, and 63.2% total dietary fiber. Other nutrients detected are macronutrients such as K > Ca > Mg > Na, micronutrients Mn > Fe, and Vitamin C. Moreover, it exhibited remarkable antioxidant activity in terms of FRC assay and DPPH assay (IC50 = 986.8mg/mL). The present study results showed that H. polyrhizus peel could be used as a potentially rich source of nutrients and natural antioxidants. Thus, it can be developed as an ingredient for food and health products. Novelty/Applications: The preliminary data obtained provide information that could support the development of products from dragon fruit peel. The conversion of these wastes into utilizable natural health products would help in reducing environmental problems Ma. Danica Ines Ramil et al. / Indian Journal of Science and Technology 2021;14(14):1097–1104 associated with processing waste disposal. Keywords: Antioxidant; Dragon Fruit Peel; Hylocereus polyrhizus; Phytochemical Screening; Nutritional Content; Heavy Metals

A data-driven comparison of commercially available testing methods for algae characterization

Algal biomass composition is often the primary driver of economic viability of research and commercial algae-based product development. As the commercial algae production field is expanding, there is a growing need for a standardized language across producers and markets in terms of biomass characterization. Similarly, to establish and design collaborative or cross-institutional algae research projects, groups need to harmonize reported compositional analysis data to ensure comparable and reproducible results. In order to provide a consistent foundation of algae quality assessment, we are working towards closely coordinated, harmonized and objective operational protocols across the algae community. We present here a demonstration of biomass composition data from different commercial analytical laboratories, specifically applied to a reference biomass material. The data highlights a lack of consistency across laboratories in methods that are available for analysis. The data presented here illustrate variability in reported biomass measurements of protein, lipids and carbohydrate content causing differences of up to 1.36, 1.43, and 3.37-fold respectively, when expressed on a dry biomass basis. When the same methods are used between the laboratories, e.g. for protein and ash measurements, the data are consistent across laboratories. However, the reported lipid content varies with the method chosen at each laboratory, and causes the calculated carbohydrate content to then absorb the remaining difference from full mass balance closure. A suggestion of a common set of analytical standard methods available commercially is provided and can help to alleviate some of the challenges the algae community faces in terms of biomass descriptive reporting. This work sets the stage for and identifies critical niches to build on an established framework for understanding and harmonizing analytical methodologies for compositional analysis of algal biomass.

Nano-Biosensing Platforms for Detection of Cow's Milk Allergens: An Overview.

Among prevalent food allergies, cow milk allergy (CMA) is most common and may persist throughout the life. The allergic individuals are exposed to a constant threat due to milk proteins’ presence in uncounted food products like yogurt, cheese, and bakery items. The problem can be more severe due to cross-reactivity of the milk allergens in the food products due to homologous milk proteins of diverse species. This problem can be overcome by proper and reliable food labeling in order to ensure the life quality of allergic persons. Therefore, highly sensitive and accurate analytical techniques should be developed to detect the food allergens. Here, significant research advances in biosensors (specifically immunosensors and aptasensors) are reviewed for detection of the milk allergens. Different allergic proteins of cow milk are described here along with the analytical standard methods for their detection. Additionally, the commercial status of biosensors is also discussed in comparison to conventional techniques like enzyme-linked immunosorbent assay (ELISA). The development of novel biosensing mechanisms/kits for milk allergens detection is imperative from the perspective of enforcement of labeling regulations and directives keeping in view the sensitive individuals.

Rapid sample clean-up procedure for aminophosphonate determination by LC/MS analysis

Aminophosphonates are commonly utilised for complexing bivalent ions such as calcium and magnesium. With regard to environmental samples, the analysis of these highly polar compounds is still challenging due to matrix effects and lacking analytical standard methods. We have recently developed a LC/MS method for common aminophosphonates without derivatisation. This LC/MS method delivers precise and accurate measurement for standard samples with very low concentration of cations disturbing the analysis. However, due to matrix effects this LC/MS method requires a sample clean-up being also applicable to natural water or wastewater samples. We developed and optimised a sample clean-up procedure applying strong cation exchange resin Dowex 50WX8. This clean-up allows a single LC/MS analysis of hydroxyethelidene(diphosphonic acid) (HEDP), aminotris(methylenephosphonic acid) (ATMP), ethylenediaminetetra(methyloenephosphonic acid) (EDTMP), diethylenetriaminepenta(methylenephosphonic acid) (DTPMP) and its major intermediates amino(methylphosphonic acid) (AMPA) and iminodi(methylenephosphonic acid) (IDMP). We compared different test conditions with six aminophosphonates in either ultra pure water or tap water. The latter was used to simulate cation concentrations typical for natural waters. To elute all aminophosphonate including AMPA, ammonium acetate addition was necessary. The addition of ammonium acetate was combinable with all tested aminophosphonates and provides high sample quality for LC/MS analysis. For acceptable recovery, the smallest aminophosphonate AMPA required the highest addition of ammonium acetate (1000 mg L-1) during the sample clean-up. Finally, the optimised clean-up procedure was successfully applied to identify and quantify phosphonates from an industrial wastewater sample. The sample clean-up procedure is simple, cheap, rapid and precise and can be further combined with solid phase extraction and more sensitive LC/MS methods.

Chemical and thermal analysis of lignin streams from Robinia pseudoacacia L. generated during organosolv and acid hydrolysis pre-treatments and subsequent enzymatic hydrolysis

Lignin streams produced in biorefineries are commonly used to obtain energy. In order to increase the competitiveness of this industry, new lignin valorization routes are necessary, for which a depth characterization of this biological macromolecule is essential. In this context, this study analyzed lignin streams of Robinia pseudoacacia L. generated during organosolv and acid hydrolysis pre-treatments and during the subsequent enzymatic hydrolysis. These lignins included dissolved lignins from pre-treatment liquors and saccharification lignins from pre-treated materials. Chemical composition and structural features were analyzed by analytical standard methods and Fourier Transform Infrared spectroscopy (FTIR), size exclusion chromatography (SEC), 13C solid state nuclear magnetic resonance (13C NMR) and 1H–13C two-dimensional nuclear magnetic resonance (2D NMR); while thermal characterization included thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). In general, all studied lignins contained a predominance of β-O-4′ aryl ether linkages, followed by resinol (β-β′) and phenylcoumaran (β-5′), with a predominance of syringyl over guaiacyl and hydroxyphenyl units. Nevertheless, the dissolved lignins revealed a removal of linkages, especially β-O-4′, leading to an enrichment of phenolic groups. Moreover, high thermal stability and good thermoplasticity were characteristics of these lignins. Contrary, the saccharification lignins exhibited a more intact structure, but with an important remaining carbohydrates content.

Analysis of Nano Ca3(PO4)2 on Bone’s Calcium Deficiency at Peak Age

In this research, we studied how the nano Ca3(PO4)2 uptake in bone mineral influenced Rattus norvegicus (Sprague Dawley) calcium deficiency status. Association of Official Analytical standard method was used for proximate analysis, meanwhile calcium and magnesium compositions were determined by atomic absorption spectrophotometry. In addition to that, ultraviolet spectrophotometry and fourier transform infrared were used to determine the content of phosphorus and infrared spectrum of transmittance, respectively. The results showed that administration of nano-sized Ca3(PO4)2 purified diet gives a higher uptake than the regular-size, suggesting that the application of nano Ca3(PO4)2 to rats suspected in a bone mass peak age with calcium deficiency may potentially prevent the occurrence of osteoporosis.

International descriptive and interventional survey for oxycholesterol determination by gas- and liquid-chromatographic methods

Increasing numbers of laboratories develop new methods based on gas-liquid and high-performance liquid chromatography to determine serum concentrations of oxygenated cholesterol metabolites such as 7α-, 24(S)-, and 27-hydroxycholesterol. We initiated a first international descriptive oxycholesterol (OCS) survey in 2013 and a second interventional survey 2014 in order to compare levels of OCS reported by different laboratories and to define possible sources of analytical errors. In 2013 a set of two lyophilized serum pools (A and B) was sent to nine laboratories in different countries for OCS measurement utilizing their own standard stock solutions. In 2014 eleven laboratories were requested to determine OCS concentrations in lyophilized pooled sera (C and D) utilizing the same provided standard stock solutions of OCS. The participating laboratories submitted results obtained after capillary gas-liquid chromatography-mass selective detection with either epicoprostanol or deuterium labelled sterols as internal standards and high-performance liquid chromatography with mass selective detection and deuterated OCS as internal standard. Each participant received a clear overview of the results in form of Youden-Plots and basic statistical evaluation in its used unit. The coefficients of variation of the concentrations obtained by all laboratories using their individual methods were 58.5–73.3% (survey 1), 56.8–60.3% (survey 2); 36.2–35.8% (survey 1), 56.6–59.8, (survey 2); 61.1–197.7% (survey 1), 47.2–74.2% (survey 2) for 24(S)-, 27-, and 7α-hydroxycholesterol, respectively. We are surprised by the very great differences between the laboratories, even under conditions when the same standards were used. The values of OCS's must be evaluated in relation to the analytical technique used, the efficiency of the ample separation and the nature of the internal standard used. Quantification of the calibration solution and inappropriate internal standards could be identified as major causes for the high variance in the reported results from the different laboratories. A harmonisation of analytical standard methods is highly needed.

Direct growth inhibition assay of total airborne fungi with application of biocide-treated malt extract agar

Indoor air pollution by airborne fungi has risen to become a common issue all over the world and it is hazardous to indoor occupants’ health as it is associated with a series of respiratory-related and skin-related diseases. Selected bioactive compounds from the food industry have been suggested to be effective against individual fungus isolated from indoor environment. However, the techniques used to evaluate these compounds were lengthy and unsuitable against total airborne fungi. Therefore, this paper describes an assay to assess the effectiveness of a bioactive compound to inhibit growth of total airborne fungi.•A combination and modification of previous methods and the NIOSH Manual Analytical Standard Method (NMAM 0800) is proposed.•This method concurrently samples the total airborne fungi and evaluates the ability of bioactive compounds (potassium sorbate in this paper), as a biocide, to treat these indoor airborne fungi.•The current method shortens the time of evaluation from 30 days to only 5 days and employs the counting of colony forming units (CFUs) to ease the measurement of the growth of fungi.

The Impact of Land Use Activities on Vegetation Cover and Water Quality in the Lake Victoria Watershed

The impact of land use activities on loss of vegetation cover and water quality was assessed in three selected sites within the Lake Victoria Basin using remote sensing technologies and standard water quality analysis techniques. The three study sites were: (i) Nzoia River Basin (Kenya), (ii) Nakivubo Wetland (Uganda) and (iii) Simiyu drainage basin (Tanzania). Lake Victoria is the second largest fresh water lake in the world and is served by a drainage basin area of over 193,000 km 2 , traversing five East African Community States; Kenya, Uganda, Tanzania, Rwanda and Burundi. This paper examines the impact of land use activities on vegetation cover and water quality based on remote sensing and Geographical Information Systems analysis combined with chemical and physical water analysis. The quality of the effluent generated by the industries found within the study sites and their effects on downstream discharge was also determined. Pesticide residues in soil and water samples were determined using analytical standard methods. Soils from some selected fields in Nzoia River basin showed high levels of compounds such as aldrin, dieldrin, endosulfan, DDT, and endrin which are together referred to as persistent organic pollutants (POPs). The physical and chemical analysis of water quality revealed high levels of phosphates and nitrates along the agricultural zones of River Nzoia Basin. The satellite images revealed that in all the three study sites land vegetation cover has continuously reduced in size. The extent of environmental degradation caused by agricultural, domestic and industrial wastes and how this affects loss of vegeta- tion cover and water quality is discussed.

Preliminary assessment of nutritional value of plant-based diets in relation to human nutrients

In this research, we present preliminary nutritional data for traditional vegetables and fruits including their content of mineral elements (calcium, potassium, sodium, zinc, and iron) and antioxidant phenolic compounds levels. Eight vegetables and vegetables were studied. Plant foods Asparagus officinalis DC, Chlorophytum comosum Linn., Cordia myxa Roxb., Portulaca oleracia Linn. and Solanum indicum Linn. were collected in Behbehan, south Iran, and also Alocacia indica Sch., Eulophia ocherata Lindl. and Momordica dioica Roxb. were collected from the south of India. Nutrients were measured with food analytical standard methods. The results of this study provide evidence that these local traditional vegetables, which do not require formal cultivation, could be important contributors to improving the nutritional content of Pune and Behbehan people. Results indicate that 50% of the vegetables have significant energy values ranging from 281.4 to 303.9 kcal/100 g. From this study, it was determined that five vegetables, namely A. officinalis, C. comosum, E. ocherata, P. oleracia and S. indicum, provide mineral concentrations exceeding 2% of the plant dry weight and are much higher than typical mineral concentrations in conventional edible vegetables; they are thus recommended for future commercial cultivation. High levels of antioxidant compounds were noticed in P. oleracia and S. indicum. The three plants S. indicum, A. officinalis and P. oleracia are suitable for high-temperature food processes.

Derating of a distribution transformer for non-linear loads

This paper deals with an important problem related to power quality that has been tackled in the literature quite often. The three-phase distribution transformer in electrical power systems is generally installed for supplying loads with rated frequency. Non-linear loads introduce harmonics to the supply and result in a different performance compared with that of the designed transformer. In this paper a three-phase 50 kVA distribution transformer is modeled using the finite element (FE) method in order to evaluate its losses under non-linear loads. Comparison of the FE computation results with the analytical standard method results shows that the latter method leads to a more conservative estimate of the transformer derating. Copyright © 2005 John Wiley & Sons, Ltd.

Dipstick Immunoassay Format for Atrazine and Terbuthylazine Analysis in Water Samples

A new dipstick immunoassay format for terbuthylazine determination, based on the use of polystyrol strips as antibody coating support, is described. The terbuthylazine calibration curve shows a linear measuring range between 1.2 and 10 μg/L. Real water samples were analyzed, and results correlate well with those from gas chromatography (GC/MS) and ELISA. No false negative results were evidenced. The dipstick immunoassay format for atrazine determination (Wittmann et al. Analyst 1996, 121, 863−869) was also used for the analyses of the same samples. Some false positive results were obtained, probably due to cross-reactivity of the atrazine monoclonal antibody for terbuthylazine. At this developmental stage, these dipsticks can be very useful as a qualitative/semiquantitative “field test” for identifying “positive” samples, reducing the number of samples to be reanalyzed in the laboratory, according to analytical standard methods (GC). Further improvements are possible to optimize the whole system on the strictly analytical aspects. Keywords: Atrazine; terbuthylazine; dipstick immunoassay; enzyme immunoassay; environmental monitoring; water samples

Comparison of dynamic test data with results of various analytical methods

For design and qualification of safety-related piping systems of nuclear power plants in the case of high dynamic loading of low load cycle and low probability linear analytical standard methods are usually applied. These methods do not really consider the fact, that such systems exhibit large margins of conservatism due to the ductility of the materials employed. The concept of strain limitation is intended to provide a more realistic design and qualification than stress limitation. Extensive seismic testing of a branched piping system was performed in order to study the elastoplastic behavior and to compare the test results to those of various analytical methods. It is shown that the results of linear best estimate calculations do not allow a reliable extrapolation to the response in the case of local plastification. Nonlinear analysis gives a good description of these effects, but need rather careful input of material data to yield exact quantitative results. As nonlinear time history analysis is rather expensive, simplified methods which allow a reliable estimation of elastoplastic strains would be useful. The application of two such methods to the presented tests provides promising results.