Functional properties, nutritional value, and industrial applications of Niger Oilseeds (Guizotia abyssinica Cass.)

Determining the Optimal Harvesting Moment of Green Forage from Guizotia abyssinica Cultivated as a Catch Crop on Silage and Its Quality Form, Fresh or Wilted Green Material, in the Two Following Years

Guizotia abyssinica is currently being used for soil improvement; however, owing to its rapid growth and high productivity, it may have value as feed for ruminants, although this has not been well studied. Thus, this research aimed to evaluate the silage quality of Guizotia abyssinica grown during the short season (July-October) as a catch crop in northern Europe when harvested 58, 68, and 90 days after sowing (DAS) over two production years. Ensiled material was analyzed to compare silage quality for the three different DAS. Two factors were analyzed factorially in the experiment: the silage preparation year (2018 or 2019) and the form of the ensiled material (fresh or wilted). We used 36 replications, 18 for each variant of the experimental factor. Harvesting at 58 DAS resulted in unsatisfactory forage fermentability, even after wilting. At 68 DAS, silage quality was satisfactory, but the dry matter content before ensiling was below 20% for both fresh and wilted forage, indicating limitations for silage use without additional wilting for that DAS harvest time. Dry matter content and water-soluble carbohydrates consistently increased as harvest was delayed. Thus, the highest silage quality was obtained from forage harvested 90 DAS regardless of differences in dry matter content. Therefore, it is possible to prepare silage at lower temperatures when the wilting process is limited by environmental conditions.

Fatty Acids and Elements Profile of Different Parts from Congress grass (Parthenium hysterophorus L.)

Congress grass (Parthenium hysterophorus L., family Asteraceae) is found generally in agricultural and vacant lands across the globe. This study investigated the fatty acids and elemental profiles of different parts including roots, stem and leaves of P. hysterophorus in the response to seasonal variation. The elemental analysis and fatty acid were determined in both the winter and summer seasons. The root, stem, and leaves powder were subjected to extraction with acetone, water, chloroform, diethyl ether, ethanol, methanol, and n-hexane to measure the extractive values. Among all the plant parts, leaves recorded the highest extractive value of 29%, and 28% with acetone and diethyl ether, respectively, while the root recorded the lowest (10.3%) extractive value with chloroform. Higher concentrations of saturated and unsaturated fatty acids were detected in all the plant parts in the winter collection than in the summer season. Parthenium hysterophorus is multi medicinal applications such as used for rheumatic pain, urinary tract infections, inflammation, diarrhea, neuralgia, and malaria. The study highlights the importance of collection time (seasons) of different parts of P. hysterophorus for the maximum extraction of both elements and fatty acids either saturated or unsaturated from the pharmacogenetic point of view.

Sterols as a biomarker in tracing niger and sesame seeds oils adulterated with palm oil

Food adulteration is a serious social problem all over the world. The oil obtained from the niger and sesame is known for its quality and has a high market value in Ethiopia. The cost of the oil obtained from these oilseed crops is high unlike other plant oils, thus prone to be mixed with other cheap oils to increase profits. The study aimed to quantify the sterol profile of niger seed and sesame oils thereby trace adulteration of these oils with palm oil. Gas Chromatography coupled to Mass Spectrometry was used to analyze the sterol fractions of oils. A blend of palm oil, at a level of 10%, with niger seed and sesame oil was prepared. In all the studied oils; sitosterol (467.2–2778.96 mg/kg), campesterol (295.9–869.85 mg/kg) and stigmasterol (125.6–920 mg/kg) were the dominant sterols identified. Lupeol, Lanosterol, and Olean-12-en-3-one were only identified in a significant proportion for niger seed oil. Moreover, cholestroltrimethyl silyl ether (19.9 mg/kg) and 24-Nor-22,23- methylenecholest-5-en-3β-ol trimethylsilyl (TMS) ethers (139.14 mg/kg) were only identified in palm oil and used to trace adulteration. An attempt made to trace these compounds by mixing palm oil at a level of 10% with niger seed and sesame oils was successfully detected its presence. Hence, as the physicochemical properties of oils can be arranged to cover adulteration, marker identification provides a reliable identity of the specific oil.

New Transcriptome-Based SNP Markers for Noug (Guizotia abyssinica) and Their Conversion to KASP Markers for Population Genetics Analyses

The development and use of genomic resources are essential for understanding the population genetics of crops for their efficient conservation and enhancement. Noug (Guizotia abyssinica) is an economically important oilseed crop in Ethiopia and India. The present study sought to develop new DNA markers for this crop. Transcriptome sequencing was conducted on two genotypes and 628 transcript sequences containing 959 single nucleotide polymorphisms (SNPs) were developed. A competitive allele-specific PCR (KASP) assay was developed for the SNPs and used for genotyping of 24 accessions. A total of 554 loci were successfully genotyped across the accessions, and 202 polymorphic loci were used for population genetics analyses. Polymorphism information content (PIC) of the loci varied from 0.01 to 0.37 with a mean of 0.24, and about 49% of the loci showed significant deviation from the Hardy-Weinberg equilibrium. The mean expected heterozygosity was 0.27 suggesting moderately high genetic variation within accessions. Low but significant differentiation existed among accessions (FST = 0.045, p < 0.0001). Landrace populations from isolated areas may have useful mutations and should be conserved and used in breeding this crop. The genomic resources developed in this study were shown to be useful for population genetics research and can also be used in, e.g., association genetics.

Impact of dietary oils and fats on lipid peroxidation in liver and blood of albino rats

OBJECTIVE

To investigate the effects of different dietary fat and oils (differing in their degree of saturation and unsaturation) on lipid peroxidation in liver and blood of rats.

METHODS

The study was conducted on 50 albino rats that were randomly divided into 5 groups of 10 animals. The groups were fed on dietary butter (Group I), margarine (Group II), olive oil (Group III), sunflower oil (Group IV) and corn oil (Group V) for 7 weeks. After 12 h of diet removal, livers were excised and blood was collected to measure malondialdehyde (MDA) levels in the supernatant of liver homogenate and in blood. Blood superoxide dismutase activity (SOD), glutathione peroxidase activity (GPx), serum vitamin E and total antioxidant capacity (TAC) levels were also measured to determine the effects of fats and oils on lipid peroxidation.

RESULTS

The results indicated that no significant differences were observed in SOD activity, vitamin E and TAC levels between the five groups. However, there was significant decrease of GPx activity in groups IV and V when compared with other groups. The results indicated that feeding corn oil caused significant increases in liver and blood MDA levels as compared with other oils and fats. There were positive correlations between SOD and GPx, vitamin E and TAC as well as between GPx and TAC (r: 0.743; P<0.001) and between blood MDA and liver MDA (r: 0.897; P<0.001). The results showed also negative correlations between blood MDA on one hand and SOD, GPx, vitamin E and TAC on the other hand.

CONCLUSIONS

The results demonstrated that feeding oils rich in polyunsaturated fatty acids (PUFA) increases lipid peroxidation significantly and may raise the susceptibility of tissues to free radical oxidative damage.