Introduction: Spice consumption is one of the globally recognized healthy nutritional practices. Most spices contain phenolic compounds that may prevent or prolong the onset of non-communicable diseases. The harvesting, processing and preparation procedures of such spices may influence the phenolic amount extracted and eventual biological availability. Literature about how extraction period and spice form affects total phenolic content yield in water infusions is scanty. Aim: This study determined the effect of spice form and length of extraction time on the total phenolic content (TPC) yield of the selected Ugandan spices infused in water. Methods: Samples of Ocimum gratissimum, Allium sativum, Cymbopogon citratus and Zingiber officinale, were collected in triplicates from Kanungu, Bushenyi and Lugazi Districts, in Uganda. Fresh and dry samples of these spices were infused in hot water for four minutes and 40 minutes and sieved with Whatman paper, No. 1. Phenolic content was measured with a spectrophotometer at Makerere University, Biochemistry Department, following Folin-ciocalteu method, using gallic acid as the reference standard. Results were analyzed using GraphPad Prism 8.0.1 software. Results: Higher TPC yield was generally observed in dry samples compared to the flesh ones and 40-minute extracts of both fresh and dry samples also had higher TPC content compared to the four minutes ones. The highest TPC yield was observed in Cymbopogon citratus (12.21±0.75 mg GAE/g) among the dry samples and Ocimum gratissimum (10.02±2.45 mg GAE/g) among the fresh samples, extracted for 40 minutes. Conclusion: Longer extraction time and sample dryness maximize TPC yield.  Ocimum gratissimum and Cymbopogon citratus may benefit consumers by improving their antioxidant status.

Introduction. Globally, the consumption and production of tea are on the rise because of its beneficial constituents. Scarce literature exists on the effects of extraction periods on the contents of the biologically important and protective phytochemicals such as phenolics, flavonoids, and antioxidants in locally produced teas in Uganda. Aim. This study determined the effects of extraction periods on the aqueous total phenolic content (TPC) of local Camella sinensis, black primary grades and green tea, and their ecological differences, their total flavonoid content (TFC), and antioxidant capacities (AOC). Methods. Samples of local tea were collected from Kigezi, Ankole, and Buganda regions, and those of green tea were purchased from a local supermarket in Uganda. Four- and 40-minute infusions were separately prepared for each sample. Total phenolic and flavonoid contents were determined using the Folin–Ciocalteu and aluminium chloride methods using garlic acid and quercetin as standards, respectively. Antioxidant content was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and ferric reducing assay power (FRAP) methods, using ascorbic acid as the standard. Results. Green tea had the highest total phenolic content both with four-minute (9.50 ± 0.25 mgGAE/g) and 40-minute (25.81 ± 1.13 mgGAE/g) extractions, followed by D1 (4.14 ± 0.33 mgGAE/g) at four minutes and PF (23.60 ± 2.37 mgGAE/g) at 40 minutes. Regionally, Kigezi (4.71 ± 0.09 and 22.13 ± 0.85 mgGAE/g) at four and 40 minutes, respectively, gave the highest TPC. In TFC, tea from Buganda (4,371 ± 0.00 μgQE/g) was the highest. In DPPH and FRAP, GT (93.82 ± 0.03%, 39.04 ± 0.02 AAEμg/mL) was the best, followed by Buganda tea (88.71 ± 0.03%, 36.99 ± 0.01 AAEµg/mL), respectively. Conclusion. Longer extraction periods increase TPC in all teas. Green tea generates approximately twice the TPC generated by black tea in four-minute infusions. Green tea gives higher TPC, DPPH, and FRAP but less TFC than some black teas and is perhaps the best in terms of protection against oxidative damage to the body.

Contamination of household foodstuffs by aflatoxins has been associated with many illnesses, especially hepatocellular cancer and malnutrition. Aflatoxins are toxins produced by fungi, especially Aspergillus flavus and Aspergillus parasiticus, usually found in food. Literature concerning the S.W. Ugandan foods that are the main aflatoxicosis route and therefore need most aflatoxin preventive measure is scanty. The current study determined the aflatoxin-susceptible food consumption frequency, prevalence, and levels of aflatoxins in selected foodstuffs in households in S.W. Uganda to establish the main food route of aflatoxicosis. Following a food frequency questionnaire, flour samples of common foodstuffs, namely, groundnuts, maize, millet, and sorghum, were randomly picked from seven districts of Southwest Uganda and analyzed for the presence and levels of aflatoxins using competitive ELISA. On average, maize and groundnut were found to be the most frequently consumed foods (seven times a week) by every family. Groundnuts had the highest mean aflatoxin level (96.5 ± 13.37 μg/kg), ranging from 6.2 to 297.3 μg/kg. Over 90% of the groundnut samples had mean aflatoxin levels greater than 10 μg/kg, the East African regulatory limit. Maize flour had a mean aflatoxin level of 34.1 ± 14.1 μg/kg, with one sample registering 336.5 μg/kg. This study found that groundnuts were the main food-route for aflatoxicosis followed by maize flour. In addition, the study re-affirmed the high prevalence and levels of aflatoxins in common food stuff in households in S.W. Uganda reported by previous studies. This study recommends further studies to elucidate its association with the observed recent increase in diseases like hepatocellular cancer and malnutrition in the region.