Chemical Composition and Biological Activities of Seeds from Four Vitis vinifera Tunisian Varieties

Thousands of polyphenolic compounds have been identified in various plants. Recently, a number of studies showed that beneficial effects of grapes are related to the presence of polyphenols, with multiple biological activities. The aim of this study was to compare the polyphenol profiles as well as biological activities of the seeds of four Tunisia cultivated grape cultivars, syrat, merlot, cabernet sauvignon and carignan. The total phenolic content of seed extracts varied between varieties and seemed to be correlated to the scavenging activity. Preliminary antibacterial results showed a good growth inhibitory activity of syrat cultivar against Staphylococcus epidermidis. To our knowledge, this is the first of such study being performed on this bacterium, known as a leading cause of Tunisian hospital-acquired infections. Gas Chromatography Mass Spectrometry analysis identified 20 polyphenol components, flavonoids being the most abundant in all extracts, followed by phenolic acids, resveratrol, tyrosol, and syringaldehyde. We also noticed a deficiency of three phenolic acid compounds (salicylic acid methyl ester, ferulic acid, Sinapic acid) as well as a flavonoid one (myricetin) in merlot cultivar, which could be responsible for its low antioxidant activity. These results will help in the selective exploitation of the seeds obtained from winemaking wastes, as well as in further pharmacological and/or in vivo investigations.

A Validated Method for Detection and Quantitation of 2’Fucosyllactose in Infant Formula Matrices

Analytical methods to assess the content of free carbohydrates in solution range from simple tests of reductive power to combinations of chromatography and mass spectrometry. Soluble carbohydrates such as lactose, maltose, fructooligosaccharides, and galactooligosaccharides are commonly found in infant formulas either as sources of energy or soluble fibers. On the other hand, a rich repertoire of lactose-based carbohydrates occurs naturally in human milk. The advent of novel biosynthesis technologies resulted in the availability of human milk oligosaccharide structures that are being used as ingredients in infant formulas. Notably, 2’Fucosyllactose has been tested in preclinical and clinical studies to determine its safety and to explore its potential health benefits in the context of pediatric nutrition. Several chromatographic methods for the analysis of human milk oligosaccharides have been published and, the main challenge associated with 2’Fucosyllactose quantitation has been to improve its resolution from lactose, which is present at concentrations around 70 g/l in both, infant formula and human milk. We developed a high-performance anion exchange chromatography method to detect and quantify 2’ Fucosyllactose in the presence of lactose by expanding the elution time between these saccharides. We validated the analytical procedure which behaved linearly (average R=0.99951) at concentrations as low as 1.75 µg/ml (limit of quantitation) with an average limit of detection of 0.43 µg/ml.

Genotypic Variation of Mineral Elements and Phytate Levels of Thirty Cowpeas (Vigna unguiculata L. Walp.) Varieties Cultivated in Burkina Faso

Cowpea is consumed as a staple food in many developing countries. The present study was undertaken to determine the variation in mineral elements and phytate concentrations in 30 cowpeas seeds varieties consumed in Burkina Faso. The composition of the thirty cowpeas seeds in total mineral varies from 5.08 % ± 0.00 to 3.55 % ± 0.08. The genotype CR06-07 showed the high content of total mineral (ashes) and the genotype Kondesyoungo local, the low content of ashes. IT81D-994 showed the high content of iron (7.07 ± 0.057 mg/100g of seeds dw), zinc (4.42 ± 0.012 mg/100 g of seeds dw), magnesium (239.80 ± 1.192 mg/100 g of seeds dw), calcium (123.39 ± 2.31 mg /100 g of seeds dw) and potassium (1201.97 ± 25.66 mg/100 g of seeds dw). Na and Se levels in the seeds showed about 4.5-fold and 7.6-fold variations between the cowpeas varieties. The genotype komcallé showed the high content of sodium (5.45 ± 0.20 mg/100 g of seeds dw) and the genotype KVx 414-22-2 had the high content of selenium (0.006 ± 0.0002 mg/100 g of seeds dw). The phytate content of the cowpeas genotypes varied from 555.61 ± 7.48 for TVU 14676 to 13.50 ± 1.14 mg/100 g of seeds dw for KVx 30-309-6G. The [Phy]/[Fe], [Phy]/[Zn], [Phy]/[Ca] and [Phy] x [Ca]/[Zn] ratios showed that the phytate content might compromise the Fe, Zn and Ca bioavailability in some cowpeas varieties. This study indicates that the cowpeas varieties might be considered as mineral source suitable for animal and human consumption.

Ascorbic Acid, Total Polyphenols and Antioxidant Activity of Ficus Carica Fruits

Ficus carica fruits are widely consumed in most part of rural areas in Northern part of Nigeria. This study was carried out to evaluate the ascorbic acid contents, tocopherols content, total polyphenols (as garlic acid equivalents), total flavonoids (as quercetin equivalents) and antioxidants capacity of Ficus carica fruits on a dry weight basis (DW). The contents of Ascorbic acid were determined colourimetrically using 2,6-dichloroindophenol; total polyphenolic compounds by Folin-Ciocalteu reagent, vitamin E was determined spectrophotometrically using standard α-tocopherols and antioxidant scavenging activity by DPPH. The value recorded was 37.00 ± 1.59 mg/100 g, 0.7 ± 0.1 mg/100 g, 384 ± 3.11 mgGAE/100 g, 21.63 ± 1.89 mgQE/100 g, 66.82 ± 7.80% and 560.25 ± 2.89%, respectively for ascorbic acid, tocopherols, total polyphenols, total flavonoids, 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity and antioxidant capacity respectively. The results obtained showed that the fruits if properly utilized can serve as a supplement of ascorbic acid, tocopherols and some polyphenols which important antioxidants with a wide range of biological benefits.

Protein Content and Amino Acid Composition among Selected South African Sorghum Genotypes

The presence of genetic diversity is essential for quality improvement to achieve balanced protein and amino acid levels in sorghum. The objective of this study was to determine the genetic diversity present among selected South African sorghum genotypes for protein and amino acid content and to select candidate lines for breeding or direct production. Fifty nine selected South African sorghum genotypes grown at two localities were analysed for crude protein content using near-infrared spectroscopy (NIR). Nineteen genotypes with high crude protein content from each location were selected and analysed for amino acid profiles using protein hydrolysates. The crude protein content of the genotypes varied from 7.69 to 16.18% across the two sites with a mean of 13.07%. The genotypes that had high crude protein content at both sites were Mammopane, AS16 M1, Macia-SA, AS19, Maseka-a-swere, and AS4. The genotype AS16cyc was the best candidate for high phenylananine content at 5.99%. Overall, the studied lines had great variability in their protein and amino acid profiles. Accessions with high protein content or amino acid values can be used in sorghum breeding programmes to increase grain nutritional quality.

Determination of Phenolic Compounds and Antioxidant Activity in Vegetables Consumed in Mekelle Tigray Ethiopia

Vegetables are widely consumed in Mekelle and imported from different regions and zones of the countries. This study was performed to evaluate the phenolic content and antioxidant activity of vegetables commonly consumed in Mekelle. Kale, carrot, cabbage and barcoli were used in the study. This research studies in detail the contents of phenolic compounds determined by the Folin−Ciocalteu reagent and the antioxidant activities determined by DPPH (using diphenyl-p-picrylhydrazyl radical). Among all vegetables kale showed highest phenolic content followed by barcoli, cabbage and carrot and the highest antioxidant activity were barcoli followed by kale, cabbage and carrot which was expressed in % of DPPH consumption after 30 minutes of reaction. The data shows the importance of antioxidant activity of vegetables in the diet.

Quality of Autmun Harvested Honey in Dangilla Wereda

The study was initiated to evaluate the physico-chemical quality of autumn harvested honey of Ethiopia particularly in Dangilla district, North West Gojjam. Twenty seven honey samples were collected from three different altitudes throughout the chain of honey handlers. The mean value of moisture content, pH, ash, titratable acidity, hydroxyl methyl furfural (HMF) and diastase activity was found to be 18.44, 4.18, 0.265, 3.88, 3.61 and 10.39 respectively. All physico-chemical quality of honey exhibit a significant (P<0.05) difference between samples collected from different altitude and across the chain. The majority of the samples were found to be in acceptable range of international honey commission standard and Ethiopian honey quality standard for all of the tested parameters. Among the tested honey samples, only 14.8% (moisture content) and 11.1% (titratable acidity) were above the standard limit. Overall, the outcome of this study shows, Dangilla district has the great potential to provide honey for local consumption as well as for exporting honey to foreign market.

Changes in Chemical Compositions of Olive Oil under Different Heating Temperatures Similar to Home Cooking

Four olive oils with varying amounts of total phenols were exposed to four different heating conditions. Chemical parameters such as free fatty acid, peroxide values, UV absorbency, total phenols, individual phenols, α-tocopherol, squalene, oleocanthal, fatty acid profile and smoke point were measured before and after heating to evaluate the impact of heating conditions on the oils. We found olive oils have reasonably high smoke point that is suitable for typical home-cooking conditions and fresh olive oil with low FFA and high phenolics are important for the conservation of olive oil quality and health benefits. A larger degree of oxidation occurred as with increase of heating time and temperature, oils with high level of phenols produced less polar compounds than oils with lower levels of phenols, including refined oils. A significant amount of total phenols and individual phenols such as oleocanthal remained after heating at 121 °C for 10 and 20 minutes, most of squalene stay intact even after heating at 220 °C.