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Aims: Rosehip seed press cake is a waste material in the industrial extraction of rosehip seed oil using cold press process. The current study seeks to evaluate the phytochemical profile, total phenolic content, total flavonoid content and DPPH radical scavenging activity of the ethanolic extract of rosehip seed press cake using standard methods and DPPH assay. Study Design:  This is an experimental laboratory report on the phytochemical properties and antioxidant potential of the ethanolic semi-solid extract (ESE) of rosehip seed press cake in order to assess its commercial viability as a food supplement. Place and Duration of Study:  The work was conducted in the Department of Chemistry, National University of Lesotho, from August 2019 to March 2020.  Methodology: Ethanol was used for the extraction of the semi-solid extract (ESE) from the rosehip seed press cake. The ESE was analysed for phytochemical constituents using standard methods. In vitro antioxidant activity of the ESE was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. For data analysis, mean and standard deviation were computed for each parameter that was quantitatively determined. Results: Presence of flavonoids, alkaloids, terpenoids, sterols, glycosides, reducing sugars, proteins, amino acids, fatty acids, phenols and polyphenols in the ESE was confirmed. Total phenolics and flavonoids content were found to be 134.44 mg GAE/g DW and 73.23 mg QE/g DW, in the range of 200 to 3000 µg/ml respectively. The DPPH radical scavenging activity of the extract was found to be in the range 10.32±3.89 and 76.06±3.48% within the concentration range and was very close to the scavenging activity of DPPH at concentrations ≥ 1500 µg/ml. The ESE showed an IC50 value of 1367.06 µg/ml relative to that of the positive control, ascorbic acid, being <200 µg/ml. Conclusion: The ESE from the rosehip seed press cake was found to be very promising as a food supplement since 50% of the 16 screened phyto-constituents were present in high concentrations; 6.25% were detected in moderate concentrations and another 6.25% were present in low concentrations. Furthermore, the ESE exhibited antioxidant properties. Further studies are recommended to obtain more information on its composition and suitability additive in animal feed or as a food supplement.

Objective: The aim of the study was to determine the quality of Liquid Digestate (LD) from selected small scale anaerobic digesters for biogas production and assess the suitability for crop irrigation. Methodology: The selection of the parameters was guided by national standards and international guidelines for the agricultural use of wastewater and wastewater treatment products. The analysis was carried out using standard methods. Results: The results showed that most of the parameters determined of the LD from the anaerobic reactors were within the ranges of the national standards and the FAO recommended guideline limits for crop irrigation with wastewater; pH (6.75-8.50), alkalinity 12.5-45.7 mg/L), EC 0.39-1.30dS/m), COD (82.3-158.0 mg.O2/L, SS (1.35-6.17 mg/L) and TDS (249.6-832.0 mg/L). The LD from the reactors contain some considerable amounts of plant nutrients; total nitrogen (11.5- 33.1 mg/L), ammonium nitrogen (2.3-22.0 mg/L), total phosphorous (1.5-121.6 mg/L) calcium (37.68-438 mg/L), magnesium (15.25-127-36 mg/L), sodium (4.67-32.47 mg/L), chloride (9.30-19.5 mg/L) and potassium (12.07-39.50 mg/L). The mean concentrations of the micronutrients cobalt (0.67-0.94 mg/L), copper (0.78-1.08 mg/L), iron (0.851.93 mg/L), manganese (0.09-0.20 mg/L), nickel (0.82-1.48 mg/L) and zinc (0.31-2.24 mg/L) were greater than the FAO guideline limits for wastewater used in crop irrigation, which suggests that the LD are potential low-cost biofertilizer. The level of toxic metals arsenic (0.65-0.87 mg/L), cadmium (0.70-0.97 mg/L), chromium (0.71-0.98 mg/L) and lead (0.55-1.46 mg/L), were higher than the recommended levels for use of treated wastewater in crop irrigation. The numbers of the common pathogenic microorganisms determined were much lower than the FAO and WHO recommended limits indicating that the liquid digestate will not pose any major health risk a biofertilizer. Conclusion: The nutrients and other parameters indicated that the quality of the LD is good enough to be used for crop irrigation without any restrictions.However, the LD should be used with caution, because of the levels of the toxic metals, which may accumulate in the soil after prolonged application. Also, extension services on best practices for the agricultural application of the LD should be made available to potential users to mitigate any potential negative environmental and health impacts.

Objective: The study aimed at determining the nutrient content of nine selected wild leafy vegetables growing in Roma Valley of Lesotho as a means to achieve food security, improve nutritional and dietary diversity and address malnutrition in rural communities. Methodology: The vegetables were analysed for proximate composition, and Ca, Mg, Na, P, K, Fe, Mn, Se, Cu and Zn and vitamin C. Analyses were carried out using standard methods. Results: The proximate analysis revealed a high in moisture (81.15 - 92.23%) statistically similar (p<0.05), some were rich in protein, vitamin C, Cu, Mn, K and Fe. Chenopodium album has the highest protein (31.53±8.65 mg/100 g) fresh weight (FW); and Rorripa nudiscula (51.4% of RDA). Chenopodium album and Rorripa nudiscula were rich in Ca, 1598.21±15.25 mg/100 g FW and 1508.50±25.40 mg/100 g FW and in Mg, 505.14±35.55 mg/100 g FW and 525.18 mg/100 g FW respectively. The vegetables were rich in K, but low in Na, with Na-to-K ratio < 1.0, indicating that the vegetables could be ideal source of balanced sodium and potassium intake in diet. The vegetables were rich in Cu with ranging from 114.4% of RDA in Hypochaeris radicata to 342.2% of RDA in Chenopodium album. Fe was abundant in Rorripa nudiscula 251.7% of RDA and Chenopodium album 187.8% of the RDA. Mn was abundant in Amaranthus cruentus 557.8% of the RDA, in Chenopodium album or 245.7% of the RDA, in Rorripa nudiuscula, 205.5% of RDA, Amaranthus thunbergii (130.9% of RDA), moderate amounts in Amaranthus caudatus (1.94±0.36 mg/100 g FW or 84.4%) and Amaranthus spinosus (83.5% of RDA). The content of Se was moderate: Rorripa nudiscula (38.3% of RDA). Amaranthus thunbergii (20.50±0.27 µg/100 g FW, 37.3% of RDA), Amaranthus spinosus (34.0% of RDA) and Lactuta serriola (20.7% of RDA). Zn was high in Chenopodium album (117.3% of RDA) moderate in Rorripa nudiscula (35.6% of RDA) Lactuta serriola (23.9% of RDA), Amaranthus spinosus (19.6% of RDA), Amaranthus caudatus (15.9% of RDA). Most of the nutrient were statistically similar at p<0.5. Conclusion: The nutrient composition indicated that the vegetables could be good source of minerals and vitamin C and could be incorporated in rural household diets to improve nutrition, address malnutrition and food insecurity.