Measurement of total starch in cereal products by amyloglucosidase-alpha-amylase method: collaborative study.
McCleary, B. V., Gibson, T. S. & Mugford, D. C. (1997). Journal of AOAC International, 80, 571-579.
An American Association of Cereal Chemists/AOAC collaborative study was conducted to evaluate the accuracy and reliability of an enzyme assay kit procedure for measurement of total starch in a range of cereal grains and products. The flour sample is incubated at 95 degrees C with thermostable alpha-amylase to catalyze the hydrolysis of starch to maltodextrins, the pH of the slurry is adjusted, and the slurry is treated with a highly purified amyloglucosidase to quantitatively hydrolyze the dextrins to glucose. Glucose is measured with glucose oxidase-peroxidase reagent. Thirty-two collaborators were sent 16 homogeneous test samples as 8 blind duplicates. These samples included chicken feed pellets, white bread, green peas, high-amylose maize starch, white wheat flour, wheat starch, oat bran, and spaghetti. All samples were analyzed by the standard procedure as detailed above; 4 samples (high-amylose maize starch and wheat starch) were also analyzed by a method that requires the samples to be cooked first in dimethyl sulfoxide (DMSO). Relative standard deviations for repeatability (RSD(r)) ranged from 2.1 to 3.9%, and relative standard deviations for reproducibility (RSD(R)) ranged from 2.9 to 5.7%. The RSD(R) value for high amylose maize starch analyzed by the standard (non-DMSO) procedure was 5.7%; the value was reduced to 2.9% when the DMSO procedure was used, and the determined starch values increased from 86.9 to 97.2%.
Measurement of carbohydrates in grain, feed and food.
McCleary, B. V., Charnock, S. J., Rossiter, P. C., O’Shea, M. F., Power, A. M. & Lloyd, R. M. (2006). Journal of the Science of Food and Agriculture, 86(11), 1648-1661.
Procedures for the measurement of starch, starch damage (gelatinised starch), resistant starch and the amylose/amylopectin content of starch, β-glucan, fructan, glucomannan and galactosyl-sucrose oligosaccharides (raffinose, stachyose and verbascose) in plant material, animal feeds and foods are described. Most of these methods have been successfully subjected to interlaboratory evaluation. All methods are based on the use of enzymes either purified by conventional chromatography or produced using molecular biology techniques. Such methods allow specific, accurate and reliable quantification of a particular component. Problems in calculating the actual weight of galactosyl-sucrose oligosaccharides in test samples are discussed in detail.
High hydrostatic pressure influences antinutritional factors and in vitro protein digestibility of split peas and whole white beans.
Linsberger-Martin, G., Weiglhofer, K., Thi Phuong, T. P. & Berghofer, E. (2013). LWT-Food Science and Technology, 51(1), 331-336.
Legumes are of high nutritional value but consumption is low in Western countries due to long processing and antinutritional factors. The development of convenience products can help to overcome these constraints. The present study investigated the effect of high hydrostatic pressure on oligosaccharides, phytic acid and total phenolic acid content, trypsin inhibitor activity and protein digestibility in peas and beans. Oligosaccharides were significantly reduced through pressurisation by up to 68% in peas and 48% in beans but reduction was lower than in cooked samples (max. 82% in peas and 80% in beans). Phytic acid was reduced by high pressure by up to 36% in peas and 11% in beans. Total phenolic acid content was reduced only in some pressurised peas and beans as compared to untreated peas and beans. Reduction of phytic acid (max. 48%) and total phenolic acids (max. 78%) through cooking was greater than through pressurisation. Trypsin inhibitor activity decreased by up to 100% in peas and 84% in beans during pressurisation. Protein digestibility increased by up to 4.3% in peas when treated at 600 MPa and 60°C regardless of time and by 8.7% in beans treated at 600 MPa at 60°C for 60 min.
Differences in chemical composition of field pea (Pisum sativum) cultivars: Effects of cultivation area and year.
Nikolopoulou, D., Grigorakis, K., Stasini, M., Alexis, M. N. & Iliadis, K. (2007). Food Chemistry, 103(3), 847-852.
The influence of the meteorological conditions during the cultivation year, along with the soil characteristics of the cultivation area, on nutrient and antinutrient compositions were evaluated for three field pea (Pisum sativum) cultivars. All varieties were cultivated in three different cultivation areas for two subsequent years. The location of the cultivation area significantly affected the proximate composition, sucrose, starch and non-starch polysaccharide contents, as well as the total tannin and phytic acid contents of peas. The cultivation year also affected all traits with the exception of starch. The major constituents of the pea seeds were significantly affected by the interaction between the cultivation area and the cultivation year. These results indicate that the composition of peas is highly dependent on the climate conditions, as well as on the soil characteristics of the cultivation area during the growing season.
Growth, feed utilization, health and organoleptic characteristics of European seabass (Dicentrarchus labrax) fed extruded diets including low and high levels of three different legumes.
Adamidou, S., Nengas, I., Henry, M., Grigorakis, K., Rigos, G., Nikolopoulou, D., Kotzamanis, Y., Bell, G. J. & Jauncey, K. (2009). Aquaculture, 293(3-4), 263-271.
Three legumes [field peas (P), chickpeas (CP) and faba beans (B)] were evaluated at two inclusion levels; 170 (L) and 350 g kg-1 (H) in a 14-week experiment with triplicate groups of 97.9 ± 6.1 g European seabass. A control diet included wheat meal, fish meal (FM) and a mixture of plant ingredients as protein sources. Diets, processed in a twin-screw extruder, were isonitrogenous and isoenergetic. All experimental diets improved growth compared to the control. Weight gain, feed intake, FCR and SGR were improved for fish fed diet CPL, while fish fed diet CPH gave higher FCR. Protein and starch digestibility were highest for the control diet, while fish fed diets CPL and PL showed significantly lower protein ADCs and lower starch ADC (P≤ 0.05) for diet PH. Among H diets, significantly better fillet yield was found for fish fed diet PH, but no other differences were found in seabass fillet organoleptic characteristics. Serum glucose and cholesterol were elevated in fish fed CP diets, while protein and triacylglycerols did not show significant differences among treatments. Fish fed the test diets showed no significant evidence of either immunosuppression or immunostimulation. Histology of liver, spleen, kidney and foregut revealed no pathological abnormalities. Field peas, chickpeas and faba beans can be included in European seabass diets up to 350 g kg-1 substituting for wheat with no negative effects on growth performance, carcass composition or organoleptic characteristics.
Effects of cultivation area and year on proximate composition and antinutrients in three different kabuli-type chickpea (Cicer arientinum) varieties.
Nikolopoulou, D., Grigorakis, K., Stasini, M., Alexis, M. & Iliadis, K. (2006). European Food Research and Technology, 223(6), 737-741.
Three different varieties of kabuli-type chickpeas were cultivated in three different cultivation areas and for two years. An evaluation was carried out to see the effect of year, of variety and cultivation area on the nutritional value of chickpeas i.e. the proximate composition, the sugars (starch, non-starch polysaccharides, rafinose series oligosaccharides and sucrose) and tannins and phytic acid contents. The cultivation area, the cultivation year and the plant variety, as well as their interactions significantly affect the composition and the sugars contents in chickpea. High proportion of the total variation for all studied parameters explained by the main effects of variety indicates a significant heritability for them. Cultivation area was found to have a significant effect on starch contents, RSO, tannins and phytic acid. Year was found to affect fat contents, NSP and sucrose contents. Rainfall is the climate characteristic that may be responsible for these year-dependent differences.
Moisture deficit stress affects yield and quality in groundnut seeds.
Chakraborty, K., Bishi, S. K., Singh, A. L., Kalariya, K. A. & Kumar, L. (2013). Indian Journal of Plant Physiology, 18(2), 136-141.
A pot study was carried out using six groundnut cultivars viz. JL 286, TPG 41, HNG 10, GG 20, CSMG 84-1 and GG 11 during Kharif 2011 to find out the influence of moisture deficit stress on yield, seed and oil quality and composition. Prolonged moisture deficit stress reduced pod and fodder yield and oil content, while accumulation of raffinose like oligosaccharides (RFOs) increased in the seeds. Stability of oil (O/L ratio) did not alter significantly due to moisture deficit stress. In general, the Virginia Runner cultivars showed more reduction in yield and other nutritional characters, but accumulated more compatible solutes in terms of RFOs to combat moisture deficit stress, indicating acquisition of tolerant characteristics in this group at the expense of yield and nutritional characters of the seed.
Differences in freeze tolerance of zoysiagrasses: II. Carbohydrate and proline accumulation.
Patton, A. J., Cunningham, S. M., Volenec, J. J. & Reicher, Z. J. (2007). Crop Science, 47(5), 2170-2181.
Cold hardiness among zoysiagrass (Zoysia spp.) genotypes varies, but the physiological basis for cold hardiness is not completely understood. The objective of this study was to determine the relationship of carbohydrate (starch, total soluble sugars, total reducing sugars, sucrose, glucose, and raffinose family oligosaccharides) and proline concentrations with the cold acclimation of zoysiagrass and the lethal temperature killing 50% of the plants (LT50). Thirteen genotypes of zoysiagrass were selected with contrasting levels of winter hardiness. Plants were grown for 4 wk of 8/2°C day/night cycles and a 10-h photoperiod of 300 µmol m-2 s-1 to induce cold acclimation. Rhizomes and stolons were sampled from nonacclimated and cold-acclimated plants and used for carbohydrate and proline analysis. Concentrations of soluble sugars and proline increased during cold acclimation, while starch concentrations decreased. Starch, sugar/starch ratio, glucose, total reducing sugars, and proline in cold-acclimated plants were correlated (r = 0.61, −0.67, −0.73, −0.62, and −0.62, respectively) with LT50. These correlations indicate that higher concentrations of total reducing sugars, glucose, and proline are positively associated with zoysiagrass freeze tolerance, whereas higher concentrations of starch appeared detrimental to freeze tolerance.
Characterization of Spanish peanut germplasm (Arachis hypogaea L.) for sugar profiling and oil quality.
Bishi, S. K., Kumar, L., Dagla, M. C., Mahatma, M. K., Rathnakumar, A. L., Lalwani, H. B. & Misra, J. B. (2013). Industrial Crops and Products, 51, 46-50.
Peanut is an important oilseed crop of tropical and sub-tropical area of the world. As a rich source of energy, vitamins and minerals, it has been accepted for table purpose as snacks in domestic and international market. The quality of seeds of sixty Spanish germplasm accessions of peanut were analyzed for their glucose, sucrose, raffinose family oligosaccharides (RFOs) and fatty acid profile. Significant genotypic differences were observed for all the traits. Among the saccharides, sucrose accounted for the major fraction with a mean value of 4.6% in the range of 2.44–7.61%; the mean value of RFOs was 0.62% in the range of 0.17–1.56% while the mean value for glucose was 0.04% in the range of 0.01–0.11%. The mean oil content was 50.3% in range of 47.0–54.6%. The fatty acid composition consisted 12.4–24.5% palmitic acid, 2.1–5.3% stearic acid, 40.3–51.5% oleic acid and 18.7–40.6% linoleic acid. Glucose content was found to be positively correlated with sucrose and negatively correlated with RFOs. The correlation between oil content and any of glucose, sucrose, or RFOs was not significant. Among the major fatty acids, a negative correlation between oleic acid linoleic acid was observed. Some genotypes were found to be superior individually for different traits and few were superior for multiple traits. NRCG 14436 was identified for high sucrose, low glucose and low oil content; NRCG 14470 was identified for low RFOs, low glucose and high oil content, and high O/L ratio; while NRCG 14404 was identified for low RFOs, low glucose and low oil content. High O/L ratio (>2.0) was observed in accessions NRCG 14472 with high oil content. Thus, superior accessions identified for different traits would be useful for peanut breeders looking for germplasm containing high oil, low oil, low RFO, high sucrose, low glucose and high O/L ratio.
Freezing tolerance attributes during spring deacclimation for three asparagus cultivars with varying adaptation to southern Ontario.
Panjtandoust, M. & Wolyn, D. J. (2016). Journal of the American Society for Horticultural Science, 141(1), 22-33.
Winterhardiness in asparagus (Asparagus officinalis) may be related to proper cold acclimation and induction of freezing tolerance in the fall, levels and maintenance of freezing tolerance in the winter, and the timing of deacclimation in the spring. Premature deacclimation and the inability to reacclimate could result in crown damage from spring freeze-thaw cycles. A field experiment was conducted, replicated over 2 years, to determine how three cultivars with varying adaptation to southern Ontario deacclimate in the spring by assessing LT50 (the temperature at which 50% of plants die) and biochemical and physiological parameters associated with freezing tolerance. ‘UC 157’ (UC), the least-adapted cultivar, deacclimated after soil temperatures rose above freezing; LT50 values increased linearly over time and were unaffected by fluctuations in soil temperature. ‘Jersey Giant’ (JG), a cultivar with moderate adaptation, rapidly deacclimated with increased soil temperature but appeared to partially reacclimate as temperatures decreased. For ‘Guelph Millennium’ (GM), the most-adapted cultivar, LT50 values did not change, maintaining the greatest levels of freezing tolerance during the spring sampling period. Although LT50 values did not differ among cultivars on the first spring sampling date, ranking for freezing tolerance at the final sampling in each year was GM>JG>UC, which is consistent with adaptation. Rhizome traits were most associated with freezing tolerance and included high concentrations of low-molecular-weight fructans (LFs), glucose, and proline and low percentage water and sucrose concentration. Overall, data suggest that the timing of deacclimation and loss of freezing tolerance in the spring may significantly affect winterhardiness; cultivars that lose freezing tolerance early and cannot reacclimate could suffer most from late spring freeze-thaw cycles.
Galacto-oligosaccharide Hydrolysis by Genetically-Engineered Alpha-Galactosidase-Producing Pseudomonas chlororaphis Strains.
Solaiman, D. K. Y., Ashby, R. D., Aneja, K. K., Crocker, N. V. & Liu, Y. (2017). Biocatalysis and Agricultural Biotechnology, 13, 213-218.
Various Pseudomonas chlororaphis strains have been shown to produce rhamnolipid, poly(hydroxyalkanoate), and antifungal compounds for plants. Ability to metabolize galacto-oligosaccharides would allow P. chlororaphis to use soy molasses as a low-cost fermentation feedstock. In this study, genetically engineered P. chlororaphis strains expressing a Streptomyces coelicolor α-galactosidase (α-gal) were constructed. In recombinant P. chlororaphis [chr::AG], the α-gal was integrated into the chromosome. P. chlororaphis [pBS-dAG], however, contains a truncated α-gal (coding for the N-terminal catalytic domain of the enzyme) on an expression vector. Real-time RT-qPCR showed 1,438-fold higher α-gal gene expression in [pBS-dAG] than [chr::AG]. In agreement with qPCR study, the results of an enzyme assay using p-nitrophenyl-α-galactopyranoside (p-NP-α-Gal) as a chromogenic substrate also showed that the cell extracts of [pBS-dAG] contained ca. 8-times higher p-NP-α-Gal-hydrolyzing activity than that of [chr::AG]. The cell extracts of [pBS-dAG] were also demonstrated to hydrolyze raffinose (32.7 ± 4.1% of the initial amount remained in the reaction mixture) > melibiose (65.4 ± 7.9%) > stachyose (72.8 ± 11.9%). The incubation of an EDTA-permeabilized (1.5 µM, 28°C, 200 rpm shaking, 20 min) P. chlororaphis [pBS-dAG] whole-cell preparation with 0.5% (w/v) raffinose in a Medium E* for 7 days resulted in the reduction of the carbon source to 0.14% (w/v), or 28% relative to the initially added amount, and the biomass reached a value of 0.46 g CDW (cell dry weight)/l. In contrast, EDTA-permeabilized wild-type P. chlororaphis did not hydrolyze the 0.5% (w/v) raffinose in the medium, and the final biomass yield was 0.26 g CDW/l.