Proximate and fatty acid composition changes in developing sandalwood (Santalum spicatum) seeds

Changes in the proximate composition of developing seeds of sandalwood (Santalum spicatum R Br) were quantified. The developing fruits were collected regularly over a period of 5 months commencing 14 days after flower opening. Rapid deposition of seed lipid began at about 91 days after flowering (DAF) at a level of 4 g kg⁻¹ and continued to about 396 g kg⁻¹ at 147 DAF. Protein and ash contents displayed similar trends to that of lipid with a corresponding decrease in moisture content. Fatty acid analysis of the seed oil demonstrated marked changes in composition during seed development. In particular, major increases in oleic and ximenynic acids were noted with corresponding decreases in the other fatty acids. © 1997 SCI.     

Quantitative and qualitative study of spelt and wheat fibres in varying milling fractions

The fibre composition of four spelt genotypes and of three wheat genotypes was studied on three grindings: bran, whole bare grains flour for all genotypes, and whole hulled grains flour for spelt only. Insoluble fibre and soluble fibre contents were measured after removal of proteins, starch and ashes from the sample (Lee, Prosky, & De Vries, 1992). Cellulose, hemicellulose and lignin contents were measured according to the same principles with different chemical degradations of the sample (Van Soest & Wine, 1967). Spelt and wheat bran and whole grain flour displayed significant statistical differences for hemicellulose and cellulose contents. Variability amongst the spelt genotypes was much higher than amongst the wheat genotypes. The study also highlighted the special profile of the true baking variety Ressac and the richness in fibres of the landrace 140. Finally, various methods of measurement were compared and a combination of these methods was proposed for cereal grains dietary fibre analysis.     

Lignification of switchgrass (Panicum virgatum) and big bluestem (Andropogon gerardii) plant parts during maturation and its effect on fibre degradability

Five cultivars of switchgrass (Panicum virgatum L) and four cultivars of big bluestem (Andropogon gerardii Vitman) were harvested at vegetative, boot and heading stages of maturity. Leaf and stem fractions were analysed for detergent fibre composition and 48-h ruminal in-vitro degradability, ester- and ether-linked non-core lignin phenolic acids, and core lignin composition. Big bluestem leaves contained more neutral detergent fibre than switchgrass, but general composition of the fibre did not differ. Stem fibre of switchgrass had relatively lower levels of cellulose and lignin at the vegetative stage than observed in big bluestem. Esterified and etherified p-coumaric and ferulic acid concentrations were generally higher in switchgrass plant parts. Yield of nitrobenzene oxidation products from core lignin was greater for switchgrass leaves, but very little difference in composition was noted. Leaf tissue contained lower concentrations of all lignin components than stems. Maturation resulted in increased total lignification, but all components did not respond in the same manner. Variation for all measures of lignification seemed to be as great within species as between the grass species. Degradability of fibre declined with maturation. The only species difference was that switchgrass fibre was more degradable at the vegetative stage. Relationships between lignification and fibre degradability were in agreement with some, but not all, previously reported relationships. Concentration of core lignin was only a significant predictor of fibre degradability when the relationship was examined across maturity stages. Within a stage of maturity, lignin composition was more closely related to fibre degradability than was concentration. However, the best predictors of fibre digestibility differed among species, plant part and maturity.     

Evaluation of near-infrared reflectance spectroscopy for predicting stover quality trait in semi-exotic populations of maize

Near-infrared reflectance spectroscopy (NIRS) analysis was investigated as a means of predicting quality parameters in semi-exotic maize stover. These parameters included crude protein (CP), neutral detergent fibre, acid detergent fibre and in vitro dry matter digestibility (IVDMD). Samples of semi-exotic maize stover were collected during three growing seasons (1989, 1990, 1991) from three locations in Catalonia, Spain. Calibration equations were obtained by multiple linear regression of conventional laboratory values on NIRS data from 84 samples and verified with 20 additional samples. Separate NIRS calibration were developed also within year (1989 and 1990, respectively). A Bran + Luebbe InfraAnalyzer model 450 was used for the study. In the multi-year calibration the coefficients of squared multiple correlation (R²) ranged from 0–81 for IVDMD to 0–92 for CP and the standard errors of calibration (SEC) ranged from 0–35 for CP to 1–46 for IVDMD. The study showed that NIRS analysis can be used to evaluate the quality of semi-exotic maize in breeding programmes.     

Seasonal variations of chemical composition in prickly pear (Opuntia ficus-indica (L.) miller)

The moisture, ash, free reducing sugar, starch, ether extractive, crude protein, amino acid and the heat energy contents of young and mature cladodes of Opuntia ficus-indica, with or without fruits, are described. The measurements were made in each of the following stages of development: vegetative growth (March), full vegetative development, and at the beginning of fructification (October). Independently of developmental stage (different cladode types) the highest values were reached always in young cladodes in the following months: moisture content in March and October; ash and free reducing sugars in March; starch and ether extractive in September and October; crude protein in March and July. Crude fibre was maximal in September and global heat energy in October. The nutritive and caloric value of cladodes are compared to other products used for livestock nutrition.     

Effect of ochratoxin A on some biochemical changes in seeds of mung bean (Vigna radiata,var Pusa 119

The effect has been studied of a range of concentrations of ochratoxin A on some biochemical parameters, viz chlorophyll, protein and nucleic acid concentrations during seed germination and seedling growth in mung beans (Vigna radiata (L) Wilczek, var Pusa 119). Reduction in levels of all the parameters resulted from ochratoxin A treatment, and the extent of reduction was directly influenced by the concentration of toxin applied.     

Rates of free fatty acid formation from phospholipids and neutral lipids in frozen cape hake (Merluccius spp) mince at various temperatures

Hake mince was stored in frozen condition at ?5°C, ?18°C and ?40°C. Samples were withdrawn periodically, and the lipids were extracted and analysed for free fatty acid and phosphorus (P) content. The free fatty acid contents were corrected for the presence of acidic phospholipids and converted into genuine free fatty acid contents. The results at ?5°C and ?18°C showed an initial rapid surge of free fatty acid formation with a concomitant decrease in P content, followed by a second phase of slower free fatty acid generation and loss of lipid-P. At ?40°C only one phase of free fatty acid generation and loss of lipid-P was observed. The rates of the enzymic hydrolyses of the phospholipids and the neutral lipids were calculated at the three temperatures. An Arrhenius plot showed that the decrease in rate of free fatty acid formation with decreasing temperature was greater for the phospholipids than for the neutral lipids. In the rapid and more important phase, the two rates were identical at about ?12°C while above this temperature the phospholipids hydrolysed faster and below it the neutral lipids. Activation energies for the enzymic hydrolyses were calculated.