Temperature and Light Effects on Germination Behaviour of African Eggplant (Solanum aethiopicum L.) Seeds

Background: A preliminary study of the African eggplant seeds obtained from farmers sources recorded a wide variation in percentage germination under ambient conditions (25±2°C). The germination percentage ranged from 0% to 25%, while fresh seeds ranged between 53% and 87%. As temperature and light are important factors of seed germination, the current study investigated the effect of temperature on the germination pattern and the influence of light interaction with temperature on seed germination of African eggplant (Solanum aethiopicum L.) under controlled conditions. Methods: Seeds of two cultivars of African eggplant were subjected to constant and alternating temperatures and under three light exposure regimes. Seed quality was accessed by per cent germination, mean germination time, time to reach 50% germination, germination index and mean daily germination. Result: The highest percentage germination under constant temperatures was recorded at 25°C (76%) and 20°C (74%). The maximum temperature and light conditions required for maximum seed germination quality (76-95%) at the shortest time (4-5 days) was 30/20°C under alternating 8/16 hours light and dark.

Nutritional Potential of Two Maturity Stages of Eggplant Solanum aethiopicum "Striped Toga" Variety Harvested in Côte d’Ivoire

African eggplant Solanum aethiopicum var. striped toga is a vegetable-fruit widely consumed in Côte d'Ivoire. However, observations have shown that the cortex was removed from the pulp during culinary preparations for various reasons. The objective of this study is to contribute to the valorization of this eggplant by showing the nutritional interest of the cortex and the pulp. The samples used in this study were collected in a market garden located south of Abidjan. After separating the cortex from the pulp, they were ground into powder and used for physicochemical analysis. The results concerning physicochemical parameters showed that the ripe pulp (Pm) compared to the ripe cortex (Cm) contained more total sugars (165±0.7 versus 107±0.70 mg/100 g DM). Whereas, the unripe pulp Pnm contained significant amounts of polyphenols and tannins compared to the unripe cortex (636±0.25 versus 328±0.04 mg/100g DM for total polyphenols; 577±0.09 versus 171±0.21 mg/100 g DM for tannins). Oxalate contents decreased in ripe parts of the fruit (Pnm: 332±2.52 and Cnm: 131±1.00 mg/100g DM in unripe eggplant versus Pm: 157.75±1.52 and Cm: 55±0 .00 mg/100g DM in ripe eggplant). Also, Solanum aethiopicum var. striped toga could play an important role in human nutrition because of their nutrients content, thus contributing to better health.

Amino acid profiles of Solanum aethiopicum, Amaranthus hybridus, and Telfairia occidentalis, common leafy vegetables in Nigeria

The aim was to evaluate the amino acid compositions of three commonly consumed leafy vegetables ( Solanum aethiopicum, Amaranthus hybridus, and Telfairia occidentalis) in Abakaliki, Ebonyi State. Leafy vegetables are important protective foods and beneficial for the maintenance of healthy living and prevention of diseases. The fresh leaves of A. hybridus, T. occidentalis, and S. aethiopicum were air-dried under room temperature for 1 week. The dried samples were further milled into a fine powder using a mechanical grinder and were stored in an air-tight plastic container. Amino acid content was determined using an applied Bio-system (phenylthiohydantoin, PTH) amino acid analyzer. Among amino acids determined in the vegetables, glutamic acid had the highest value with 12.59, 11.20, and 11.96 g/100 g protein, which was followed closely by leucine with 9.81, 7.94, 9.28 g/100 g protein, and aspartic acid with 8.99, 8.62, and 9.74 g/100 g protein in S. aethiopicum, A. hybridus, and T. occidentalis, respectively on dry weight bases. The leaf that contained the highest total amino acid (TAA) was S. aethiopicum with 88.69 g/100 g protein followed by T. occidentalis with 80.39 g/100 g protein while A. hybridus being the lowest, had 73.38 g/100 g protein. The limiting essential amino acid was tryptophan with 1.98 g/100 g protein while leucine with 9.0 g/100 g protein was the most abundant TAA. The percentage concentration of different groups of amino acid in vegetables revealed that total essential amino acid (TEAA) had 54.85%, total non-essential amino acid (TNEAA) had 48.27%, total neutral amino acid (TNAA) had 22.24%, total acidic amino acid (TAAA) had 32.48%, total basic amino acid (TBAA) had 11.53%, total aromatic amino acid (TArAA) had 11.89% while total sulfur amino acid (TSAA) had 3.94%. The results indicate that the vegetables studied are rich in essential amino acids and could serve as a good source of quality protein. Therefore, they could be recommended as food supplements, especially when animal proteins become more expensive as a source of protein.

Effects of oven drying on the physicochemical composition of eggplant (Solanum Aethiopicum L.)

The objective of this work is to determine the effects of oven drying on the physico-chemical composition of eggplant (Solanum Aethiopicum L.). The samples were collected in the field school of the University Jean Lorougnon Guédé in Daloa. The water contents, pH, titratable acidity and vitamin C were determined at different temperatures (50 ° C, 60 ° C, 80 ° C and 90 ° C) and time. Analyzes show that the moisture (92 to 5%), pH (5.67 to 3.44) and vitamin C (1.095 to 0.508 mg EAA / 100g) contents decrease progressively as a function of the drying time and over time. as the temperature rises. However, the titratable acidity contents of eggplants increase (0.0153 to 0.229 meq / 100g) gradually with increasing temperature. Increasing temperature and time lead to a decrease in humidity, pH and vitamin C and an increase in the titratable acidity content of eggplants during drying. Keywords: Eggplant; Solanum Aethiopicum, drying, vitamin C