Bioactive compounds of Prosopis africana oil (african mesquite) using gas chromatography and mass spectrometry (GC-MS) technique

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Introduction
Prosopis africana "african mesquite" is an evergreen multipurpose leguminous plant belonging to the family Fabaceae.It has about 45 species and it is widely distributed in most part of Africa, Asia and America (Adikwu et al., 2001;Ugwoke et al., 2019).The seeds of P. africana are rich in phytoconstituents such as: alkaloids, tannins, flavonoids, terpenoids, steroids, saponins, steroids, glycosides, and phenols with significant therapeutic properties (Alagbe, 2021;Olorumaiye et al., 2019).The seeds has antioxidant, antifungal, antimicrobial, antifungal, angelsics, antipyretic, anti-proliferative, antifungal, anti-inflammatory, hepato-protective, antiprotozoal, anti-androgenic and cytotoxic properties (Harzallah;Jannet, 2005;Singh et al., 2023) and it also contains important minerals such as Calcium, Potassium, Zinc, Manganese, Magnesium, Copper and Sodium (Ferguson et al., 2015;Oluwafemi et al., 2021).These minerals are vital for the activation of key enzymes that provide a greater protection from diseases (Alagbe, 2022;Shittu;Alagbe, 2020).Moreover, P. africana seeds contains amino acid alanine, proline, valine and isoleucine which are the main structural protein found in connective tissues of animals (Peter et al., 2009;Barminas et al., 1998).The medicinal properties of plants depends on its composition of phytoconstituents or bioactive compounds (Ogunshe et al., 2007;Le Houe'rou, 2003).The stem bark and root decoction of Prosopis are used traditionally for the treatment of rheumatism, cough, malaria, bronchitis, skin diseases, gastrointestinal and sexually transmitted infections (Agubosi et al., 2022).Fermented seeds of the plant can be used in the preparation of soup because of its sweet smell (Gberikon et al., 2015;Platt, 1980).
Preclinical investigations has shown the pharmacological responses of P. africana oil to inhibit the activities of some pathogenic organisms such as; Salmonella spp, Candida albicans, Escherichia coli, Bacillus subtilis, Bacillus pumilus, Bacillus licheniformis and Bacillus megaterium (Oguntoyinbo et al., 2010;Alagbe et al., 2023).Aqueous and ethanolic extracts from the leaves and stem bark of P. africana can be used for the treatment of diarrhea and coccidiosis in poultry (Adewale et al., 2021).Identifying the bioactive compounds in a medicinal plant could lead to the production of novel drugs (Alagbe, 2020).One key method in identifying unknown compounds, quantification and characterization is the use of gas chromatographymass spectrometry (GC-MS) technique.
Investigating the bioactive compounds in a sample will give a clue on its efficacy and safety.Hence, in view of the immense medicinal properties in P. africana seed.This study was designed to evaluate the phytochemicals or bioactive compounds in Prosopis africana oil using gas chromatographymass spectrometry (GC-MS) technique.

Experimental site
This study was carried out at the Department of Animal Science Laboratory, University of Abuja main campus along Airport road, Gwagwalada, Abuja, Nigeria located between latitudes 8o571 and 8o551N and longitude 7o051 and 7o061E (Balogun, 2001).

Collection, identification processing of Prosopis africana oil
Prosopis africana seed were purchased from a local market in Gwagwalada, Nigeria.It was identified and authenticated at the Herbarium of Department of Biological Sciences, University of Abuja, Nigeria with a voucher number ABJ/09A/20.It was shade dried for 13 days and grinded into powder using a laboratory blender (Panasonic, Model EDH-023) and stored in a labeled polythene bag for further test.

Extraction of Prosopis africana oil using steam distillation method
Prosopis africana oil was extracted using steam-distillation technique, the entire extraction procedure requires digital weighing scale, round bottom flask, distilled water, glass yarn heating mantle, measuring cylinder, separatory funnel.50 grams of grinded Prosopis seed was weighed into a round bottom flask, mixed with 250 mL of distilled water.The mixture was placed in a glass yarn heating mantle, adjusted to a temperature of 80 °C before setting up the condenser above the round bottom flask.The mixture is boiled vigorously for 15 min and the distillate was collected in a beaker until no more droplets of oil come over followed by the addition of 5 grams of sodium chloride and stirred vigorously.Thereafter, the distillate was transferred into the separatory funnel and evaporated in a steam bath to obtain P. africana oil (PRAO).

Conclusions
It can be concluded that Prosopis africana oil possess several health promoting properties (antimicrobial,

Table 1 .
Bioactive compounds of Prosopis africana oil as detected by GC-MS.