Abstract Cancer is a disease that invades the lives of millions of people each year. Chemotherapy is currently the most effective treatment however resulting in many adverse effects to the human body. Alternative treatments are being explored to overcome this obstacle. Peptides that possess radical scavenging activity and bioactive properties can be advantageous in prevention and treatment of chronic diseases. In this study, Lablab purpureus isolate and its hydrolysates (trypsin, pepsin and alcalase) were analysed for radical scavenging potential (DPPH, ABTS, superoxide radical scavenging and FRAP) and antiproliferative activity. Antiproliferative activity was confirmed with the peptides ability to induce apoptosis (Caspase 3/7 activity and Annexin V-PI). The lowest inhibitory concentrations (IC50) for DPPH, ABTS and Superoxide radical scavenging ranged between 1.81-4.47, 1.73-2.42 and 1.36-4.41 mg/mL, respectively. FRAP ranged from 19.20 to 21.94 mg/mL. Generally, it is considered that a good antioxidant encompasses antiproliferative potential. Cell lines, A549, MCF-7 and HEK293, treated with pepsin hydrolysate showed (IC50 values of 119.6, 9.80 and 13.86 µg/mL). The isolate and pepsin were chosen for apoptotic studies. The pepsin hydrolysate showed the highest inhibition in the cancerous cell lines (A549 and MCF-7) without greatly effecting normal cells (HEK293), and the isolate was selected for comparative analysis. Annexin V-PI staining showed cells in different stages of apoptosis (cells during early apoptosis; A549, 42%; MCF-7, 17%; HEK, 34%). Caspase 3/7 assay demonstrated that the peptide causes an increase in caspase activity. Peptides have the potential to act as chemo-preventative agents due to their antioxidant and apoptotic abilities.

Abstract New insights on the use of peptides as therapeutic agents in the treatment of cancer have emerged with reports showing anti-tumour activity of peptides, predominantly derived from animals or microorganisms. Amaranth is a pseudocereal traditionally acknowledged to possess pharmacotherapeutic properties. Thus, the aim of this study was to compare the in vitro anti-cancer effect of amaranth protein hydrolysates (alcalase, trypsin, and pepsin). Protein hydrolysates were tested for their antioxidant activity together with the anticancer and apoptotic potential. Antioxidants results revealed hydrolysates to have a greater antioxidant effect than un-hydrolysed protein, with results exceeding that of controls. The MTT cytotoxicity assay conducted on MCF-7, A549 and HEK 293 cell lines showed the trypsin hydrolysate to exhibit a preeminent anti-cancer effect. Annexin V-FITC flow cytometry showed an increased number of early apoptotic and late necrotic cells compared to untreated cells, further validated by caspase 3/7 activity. These assays confirmed the induction of apoptosis of the trypsin hydrolysate thereby demonstrating that the hydrolysate can be used as a potential therapeutic against selected cancers.

Abstract Intestinal bacteria utilize the constituent of ingested food for their metabolic activities making the gut microbiota a target in the modification of functional foods. This study examines the effect of modified citrus pectin and encapsulated probiotic, Lactobacillus acidophilus ATCC 4356 on colon lactobacilli microbiota in healthy Balb/c mice. Mice were orally administered once daily with modified citrus pectin alginate probiotic, alginate calcium probiotic, modified citrus pectin and water for 28 days. Faecal lactobacilli count were determined using automated colony counter Doc-It® imaging station. The number of faecal lactobacilli in the modified citrus pectin alginate probiotic-treated mice significantly increased at day 7, 14 and 28 [7.99 ± 0.22, 8.32 ± 0.08 and 8.36 ± 0.23 (log10cfu/g) respectively]. A little or no increase in the faecal lactobacilli count was noted in the modified citrus pectin-treated mice. Modified citrus pectin alginate combined with live probiotic, Lactobacillus acidophilus ATCC 4356 supplements can be used as probiotic therapy to improve the intestinal lactobacilli microbiota in healthy host.

Abstract This study investigated the effect of processing on anti-nutritional factors of thirteen traditional leafy vegetables collected in Kwa Zulu-Natal, South Africa. The aim was to determine whether processing reduced anti-nutrient levels of leafy vegetables. The vegetables were boiled in a plant-to-distilled water ratio of 1:4 (w/v) at 97 °C for a time period of 5 and 15 min. The vegetables studied were: Amaranthus dubius, Amaranthus hybridus, Asystasia gangetica, Bidens pilosa, Ceratotheca triloba, Chenopodium album, Emex australis, Galinsoga parviflora, Guilleminea densa, Momordica balsamina, Oxygonum sinuatum, Physalis viscosa and Solanum nigrum. From this study, it was determined that non processed samples contained anti-nutrients such as tannins, phytic acid, alkaloids, oxalic acid, and cyanogenic glycoside. Both boiling parameters were effective in reducing the tannin, phytic acid, alkaloid, oxalic acid and cyanogenic glycoside contents of all 13 traditional leafy vegetables. The results of this study provide evidence that the local traditional leafy vegetables which the population is so reliant upon, are important contributors to micronutrient malnutrition in developing countries and can be minimized through common boiling methods for a minimum of 5 and maximum of 15 minutes.

Abstract Hibiscus sabdariffa is an under-utilized plant that has reported to have great potential in the food industry. The vibrant red pigment from the calyces indicate a source of anthocyanins. Anthocyanins would make ideal natural food colourants with additional nutritional benefits however stability is a hindering factor. Stability studies were the main focus of this study. Crude anthocyanins were extracted using four different solvent systems. The crude extracts were analysed under the following parameters; heat (50 and 80 °C), light (darkness and 20 W light) and pH (pH 1-9) stability. Degradation kinetic studies were done on thermally treated samples. Radical scavenging ability was thereafter calculated. Anthocyanidins were identified and quantified by HPLC coupled with a Diode Array Detector (DAD). Total phenolic content was determined with Folin – Ciocalteu’s method. Approximately 87% of pigments were retained when heated at 50 °C while heating at 80 °C resulted in 61% pigment retention. The pH stability of samples incubated for 7 days indicated that crude anthocyanins degraded slower at acidic pH. Light stability showed slower degradation in dark incubated samples resulting in 84% pigment retention after a 10 day period. H. sabdariffa shows potential for the application of a food in products such as jelly and yoghurt.