Antioxidant, antibacterial, and anti-SARS-CoV Activity of Commercial Products of \u3cem\u3eXylopia\u3c/em\u3e (\u3cem\u3eXylopia aethiopica\u3c/em\u3e)

Xylopia aethiopica (Annonaceae) is a spice and medicinal plant that grows wild in many West African countries (from Liberia to Nigeria) and is locally known as Guinea pepper, grains of Selim, hwentia and uda. The dried fruits are used as a flavoring for soups and traditionally in decoctions as an analgesic and anti-inflammatory, as well as a treatment for infections. The medicinal properties of the fruits are associated with the presence of phenolics and essential oil constituents. We studied the total phenols, total flavonoids, and antioxidant activity in different X. aethiopica extracts using spectrophotometry. We found variation in total phenolic and flavonoids and antioxidant capacity between different samples and different extraction solvents. Antibacterial activity against Escherichia coli and Bacillus subtilis were evaluated using a spectrophotometric assay and Kirby-Bauer test. Additionally, a pseudoviral cell-based assay was used to test the antiviral activity against severe acute respiratory syndrome coronaviruses (SARS-CoV-1 and SARS-CoV-2). High total phenolic and flavonoid content was correlated with high antioxidant capacity. Results of antibacterial tests indicated that one Xylopia extract potentially has strong antibacterial activity against gram-positive bacteria B. subtilis. The pseudoviral assay showed moderate antiviral activity against SARS-CoV-1 and SARS-CoV-2

Characterization of n-Hexane sub-fraction of Bridelia micrantha (Berth) and its antimycobacterium activity

<p>Abstract</p> <p>Background</p> <p>Tuberculosis, caused by <it>Mycobacterium tuberculosis </it>(MTB), is the most notified disease in the world. Development of resistance to first line drugs by MTB is a public health concern. As a result, there is the search for new and novel sources of antimycobacterial drugs for example from medicinal plants. In this study we determined the <it>in vitro </it>antimycobacterial activity of <it>n</it>-Hexane sub-fraction from <it>Bridelia micrantha </it>(Berth) against MTB H₃₇Ra and a clinical isolate resistant to all five first-line antituberculosis drugs.</p> <p>Methods</p> <p>The antimycobacterial activity of the <it>n</it>-Hexane sub-fraction of ethyl acetate fractions from acetone extracts of <it>B. micrantha </it>barks was evaluated using the resazurin microplate assay against two MTB isolates. Bioassay-guided fractionation of the ethyl acetate fraction was performed using 100% <it>n</it>-Hexane and Chloroform/Methanol (99:1) as solvents in order of increasing polarity by column chromatography and Resazurin microtiter plate assay for susceptibility tests.</p> <p>Results</p> <p>The <it>n</it>-Hexane fraction showed 20% inhibition of MTB H₃₇Ra and almost 35% inhibition of an MTB isolate resistant to all first-line drugs at 10 μg/mL. GC/MS analysis of the fraction resulted in the identification of twenty-four constituents representing 60.5% of the fraction. Some of the 24 compounds detected included Benzene, 1.3-bis (3-phenoxyphenoxy (13.51%), 2-pinen-4-one (10.03%), N(b)-benzyl-14-(carboxymethyl) (6.35%) and the least detected compound was linalool (0.2%).</p> <p>Conclusions</p> <p>The results show that the <it>n-</it>Hexane fraction of <it>B. micrantha </it>has antimycobacterial activity.</p

ASSESSMENT OF THE NUTRITIONAL VALUE OF FADOGIA TRIPHYLLA HERBAL TEA OF ZAMBIA

Fadogia triphylla, a perennial shrub that can reach up to 120 cm is used both as a local herbal tea and in traditional medicine. Traditional healers have reported the use of Fadogia spp. in the treatment of coughs, ascariasis, abdominal pains and stomachs. There is limited information about the nutritional and medicinal value of the leaves of this local tea. Thus, the objective in this study was to asses the nutritional value and herbal tea characteristics of F. triphylla leaves from Zambia. Fadogia triphylla leaves were collected from Shatumbu district, Lusaka at two different times (June 2006 and August 2006). The dry Fadogia leaves were then subjected to foreign matter analysis and moisture content analysis. Total ashes and total insoluble ashes, total phenols, antioxidant activity, and elemental and caffeine. The leaves are high in antioxidant components (8%) and rich in minerals (7%), potassium (1%), calcium (1.3-1.8%) and manganese (90-71 mg/100 g). No caffeine was detected in the leaves based upon HPLC analysis and pure caffeine as the standard, permitting the labelling of this bush tea to be caffeine-free infusion. Initial quality standards were developed for the first time to define quality in Fadogia tea. While a preliminary study, we found the leaves to be high in antioxidant components, rich in minerals (e.g. potassium, calcium and manganese), caffeine-free and the herbal tea to have a pleasant taste. Fadogia leaves contain interesting functional properties that show the leaves to be healthy and nutritional and which may assist in the commercialization of this indigenous tea into non-local markets