John Ogbaji Igoli

Joseph Sarwuan Tarka University, Makurdi Nigeria

Phytochemical investigation of the root bark of Caesalpinia bonduc has yielded a novel diterpene as well as seven other known compounds. The new diterpene was characterised as 5-hydroxyvihaticanal (Caesaldekarin M) and the known compounds were Caesaldekarin C, F and H, Demethylcaesaldekarin C, Vouacapen-5, 19-diol, Caesalmin D and E-Caesalpin. The...

Natural products have been successfully used for treating various ailments since ancient times and currently there are several natural product based anti-cancer agents used as the main therapy to treat cancer patients or as a complimentary treatment to chemotherapy or radiation. Balanocarpol, which is a promising natural product that has been isola...

The Nigerian and South African varieties of Siphonochilus aethiopicus were examined for their phytochemical constituents. The ethyl acetate extract of the rhizomes of the South African variety yielded a novel diarylheptanoid, 2,3-diacetoxy-7-(3′′,4′′-dihydroxy-5′′-methoxyphenyl)-1-(4′-hydroxy-3′-methoxyphenyl)-5-heptene and the flavonoid 3,7-dimeth...

Calliandra portoricensis is a medicinal plant growing freely in Nigeria. It is used traditionally to treat tuberculosis, as an anthelmintic and an abortifacient. Phytochemical fractionation and screening of its root extracts has yielded a novel (5-hydroxy-7-methoxy-4-oxo-1-chromanyl)-4-methoxy-p-benzoquinone (breverin)-substituted cassane diterpene...

The powdered roots of the medicinal plant Acacia nilotica were extracted with hexane and ethyl acetate, and the extracts were subjected to column chromatography for the isolation of potentially bioactive compounds and their screening against kinetoplastid pathogens. NMR and HREI mass spectrometric analyses identified two new diterpenes, characteriz...

Aim/background: Lomariopsis guineensis (Underw.) Alston is an epiphytic climbing fern. It is widely distributed in Africa where it is also used in traditional medicine and as food. There are no previous reports of any constituents of the plant, hence this study to isolate any phytoconstituents. Method: The ethyl acetate extract of the leaves was su...

The nutrient recovery potentials of the plants Ocimum basilicum and Corchorus olitorius in a polyculture aquaponic system were evaluated. Two treatments of polyculture aquaponics (fish + crayfish + O. basilicum; and fish + crayfish + C. olitorius) and a conventional recirculating aquaculture system (RAS) as the control (fish + crayfish) were set up...

Chemical investigation of propolis samples from southern Nigeria led to the isolation of cycloartanetype triterpenes namely: 24-methylene cycloartanol and ambonic acid along with pentacyclic triterpenes: Lupeol and α, β-amyrins. All compounds were identified and structures elucidated using proton nuclear magnetic resonance (1HNMR) spectroscopic dat...

NMR and FTIR analyses were used to evaluate methanol extracts from Eastern Nigeria propolis. The main component of the extract was determined to be lupenone (LEU). Gravimetric, electrochemical impedance spectroscopy, and computational approaches were employed in the studies of the adsorptive and inhibitive effects of the propolis extracts on the c...

Propolis is a resin that is gathered by bees from exudates produced by various plants. Its exact chemical composition depends on the plants available near the hive. Bees use propolis to coat the surfaces of the hive, where it acts as an anti-infective. Regardless of the chemical composition of propolis, it is always anti-protozoal, probably because...

Tapinanthus sessilifolius (Loranthaceae) (P. Beauv) Blume. commonly known as African mistletoe is a well-known medicinal plant in Africa and Europe. A bioassay-guided isolation of the plant constituents was carried out to identify potential anti-hyperglycemic agents. The hexane extract was discovered to be active which yielded two triterpenoids; be...

Propolis is a honeybee product employed in folkloric medicine and as a source of various bioactive constituents. Chromatography is a proven method for isolating natural compounds and the ethyl acetate extracts of propolis from Owerri in Imo State and Umuahia in Abia State Nigeria were subjected to column chromatography and the isolated compounds we...

Propolis is a honeybee product employed in folkloric medicine and as a source of various bioactive constituents. Chromatography is a proven method for isolating natural compounds and the ethyl acetate extracts of propolis from Owerri in Imo State and Umuahia in Abia State Nigeria were subjected to column chromatography and the isolated compounds we...

Plant oils form a major component of our nutrition and also have various applications in medicine and industry. In Benue state, many plant seed oils are used for food and as components of traditional medicine. However, the levels of unsaturation of many of these oils has not been determined. A study of twenty (20) medicinal plants (Abrus precatoriu...

Tapinanthus globiferus is a mistletoe plant used in traditional medicine throughout Africa. A chloroform extract of the aerial parts of the plant epiphytic to Parkia biglobosa trees was fractionated using silica gel column chromatography. Three compounds identified as 7, 15-dihydroxy-lup-20-(29)-ene-2--palmitate, (R)-6-[(S)-2-hydroxy-4-(4-hydro...

Neglected and underutilized plant species (NUS) in Tanzania are maintained by socio-cultural preferences. However, a majority remains inadequately characterized and neglected by research and conservation initiatives. Over long time ago, the NUS have been part of the major component in the food systems of local communities especially in the dryland...

Green synthesis of silver nanoparticles using stem bark extract of Lonchocarpus laxiflorus plant as a reducing agent following a simple, effective, and eco-friendly route was reported in this work. UV-vis, FTIR SEM/EDX, and Backscatter Electron Detector (BSD) analysis were employed in the characterisation of the nanoparticles synthesised. The dispe...

Chemical composition of propolis has been reported to be phyto-geographical in nature. The aim of this study was to isolate and characterize chemical compounds from hexane and ethyl acetate extract of propolis obtained from Gboko. To isolate compounds, extract was subjected to column chromatography by gradient elution using two solvent mixtures - h...

Profiling a propolis sample from Papua New Guinea (PNG) using high-resolution mass spectrometry indicated that it contained several triterpenoids. Further fractionation by column chromatography and medium-pressure liquid chromatography (MPLC) followed by nuclear magnetic resonance spectroscopy (NMR) identified 12 triterpenoids. Five of these were o...

Propolis obtained from various geographical regions has yielded various phyto-constituents and exhibited several biological activities. The aim of the present study was to isolate and characterize chemical compounds from hexane and ethyl acetate extract of propolis obtained from Gboko. To isolate compounds, extract was subjected to column chromatog...

Rural communities in developing countries have water sanitation and hygiene (WASH) needs. The absence of this has led to a high prevalence of diseases as the life cycle of several neglected tropical diseases has revealed. Transmission of diseases such as helminths, schistosomiasis, cholera can be prevented by high standards of sanitation and hygien...

In this study, the essential oils obtained from the fruits of Amomum villosum var. xanthioides by three different extraction methods (hydrodistillation, steam distillation, and microwave-assisted hydrodistillation) were reported for their yield, chemical composition and antimicrobial activity. The oils obtained were analysed using gas chromatograph...

Cassava roots undergo postharvest physiological deterioration (PPD), and for most varieties it sets in within 72 hours of harvest. An untargeted metabolomics approach combined with a data-driven approach for statistical analysis was used to characterize and profile high beta-carotene cassava varieties with the aim of identifying any relevant metabo...

Cassava tubers suffer from postharvest physiological deterioration (PPD) which normally sets in within 72 hours of harvest. This study examines the role of scopoletin and carotenoids in the onset or delay in PPD in two transgenic varieties EC20-7 and EC20-8 compared to a wild variety TME-7. Scopoletin and carotenoids were quantified by liquid chrom...

Ethanolic extracts of samples of temperate zone propolis, four from the UK and one from Poland, were tested against three Trypanosoma brucei strains and displayed EC50 values < 20 µg/mL. The extracts were fractionated, from which 12 compounds and one two-component mixture were isolated, and characterized by NMR and high-resolution mass spectrometry...

A new eusdesmane sesquiterpenoid, characterised as 5-acetoxy-9aβ-hydroxy-4aαH-3,5α, 8aβ-trimethyl-4, 4a, 6, 7, 8a, 9-hexahydronaphtho-([2, 3 b]-dihydrofuran-2-one)-8-one or phaeusmane F acetate (1) has been isolated from the rhizomes of the South African variety of wild ginger (iphonochilus aethiopicus (Schweinf) B.L. Burtt). The compound was obtai...

Propolis is a resinous substance produced by bees with a wide range of medicinal uses. It is collected by bees from buds, leaves and bark exudates of several plants in both tropical and temperate regions. Propolis is sometimes referred to as "bee glue" as it is produced by bees for sealing and protection of their hives. Exploration and research int...

A selected sorbent granulated activated charcoal solid - phase extraction was developed and used to extract diazinon from distilled water (TDW), distilled deionized water (DDW) and stream water (DW) was studied in the laboratory. Prior to the extraction, the half-live of the diazinon was determined in buffer solutions of pH 6, 7 and 8. The study sh...

Trypanosomiasis and leishmaniasis are a group of neglected parasitic diseases caused by several species of parasites belonging to the family Trypansomatida. The present study investigated the antitrypanosomal and antileishmanial activity of chalcones and flavanones from Polygonum salicifolium, which grows in the wetlands of Iraq. The phytochemical...

Propolis is a natural product produced from bees which have been acclaimed a medicinal product. In this study, greenish propolis samples collected from a private apiary in Umudike of Abia State, Nigeria were subjected to column chromatography using ethyl acetate as solvent. The eluates that were soluble in ethyl acetate only was subjected to liquid...

The present study investigated the nutritional and phytochemical properties of seeds oils and flours from Pachira aquatica seed cultivated in Nigeria. Proximate composition and phytochemical composition were determined by standard methods while mineral content of the seed flours and oil was determined using Thermo Scientific iCAP 6200 Inductively C...

The West African country Nigeria features highly diverse vegetation and climatic conditions that range from rain forest bordering the Atlantic Ocean in the South to the Desert (Sahara) at the Northern extreme. Based on data from the World Conservation Monitoring Center of the United Nations Environmental Protection, Nigeria, with ~5,000 documented...

A bioassay-guided phytochemical investigation of propolis samples from Tanzania and Zambia that screened for activity against Trypanosoma brucei has led to the isolation of two novel flavanones with promising anti-trypanosomal activity. The compounds were characterized based on their spectral and physical data and identified as 6-(1,1-dimethylallyl...

The kinetoplastids are protozoa characterized by the presence of a distinctive organelle, called the kinetoplast, which contains a large amount of DNA (kinetoplast DNA (kDNA)) inside their single mitochondrion. Kinetoplastids of medical and veterinary importance include Trypanosoma spp. (the causative agents of human and animal African Trypanosomia...

Bergenin is an important constituent of Flueggea virosa (Euphorbiaceae), a tropical plant with several traditional uses. While there are numerous reports on the isolation and characterization of bergenin, a rapid, high-throughput, readily accessible method for the isolation and characterization of the compound locally has not been reported. Isocrat...

The absence or idle state of analytical equipment such as nuclear magnetic resonance spectroscopy, mass spectrometers and chromatographic techniques has constrained natural products research in Nigeria. Presently, gas chromatography-mass spectrometry has become the more easily available method in Nigeria for the identification of natural products i...

Calliandra portoricensis is a plant widely used in Nigerian ethnomedicine for the treatment of tuberculosis and other respiratory conditions. In view of its traditional use, the present study is aimed at the isolation and identification of bioactive components or secondary metabolites which may be responsible for its biological activity. The air dr...

Youth unemployment in Nigeria. A case study of youths in Makurdi town in Benue State Nigeria.

A presentation on the nature and composition of propolis samples from Nigeria and their potential for drug discovery, economic and chemical exploitation.

The first report on the isolation of isosativan from Nigerian propolis

The stem bark of Cassia sieberiana was extracted with methanol and the methanol extract partitioned with chloroform. Column chromatography of the chloroform fraction over silica gel yielded a novel benzofurochromene [2-(4-hydroxylphenyl)-7’-1, 2-dihydroxy-1-phenylpropyl)-4’, 6’-dihydroxy [1] phenylbenzofuro (2, 3-c)-7’-chromene], lupeol and epiafze...

Psidium guineense Sw. (Myrtaceae) is a shrub distributed all over South America and Brazil. Its leaves are traditionally used to treat digestive problems and infections. Several biological activities have been reported for P. guineense extracts, however phytochemical studies are scarce. The present study is on the isolation of compounds from P. gui...

Extracts and compounds from the sawdust and stem bark of Erythrophleum suaveolens were studied for antifungal activity. The plant materials were extracted using hexane, ethyl acetate and methanol to obtain the crude extracts. Column chromatography over silica gel was used to purify the extracts and obtain pure compounds. Betulin and 21-acetoxylupen...

Extracts of 35 samples of European propolis were tested against wild type and resistant strains of the protozoal pathogens Trypanosoma brucei, Trypanosoma congolense and Leishmania mexicana. the extracts were also tested against Crithidia fasciculata a close relative of Crithidia mellificae, a parasite of bees. Crithidia, Trypanosoma and Leishmania...

Landolphia owariensis is a plant common in West Africa with many ethnomedicinal uses. The leaves of the plant were investigated for phytochemical constituents. Successive extraction and chromatographic purification led to the isolation of two flavonoid glycosides myricitrin and quercitrin, and the triterpenoid and sterol glucoside, α-amyrin and dau...

The relative composition of the fatty acids in Pachira aquatica seed oil were determined using GC-MS and 1H NMR. The results obtained from GC-MS and 1H NMR show that the oil contained saturated fatty acids (>67%), oleic acid (>18%), linoleic (>3%) and linolenic acid (≤0.01%). 1H NMR gave more reliable and reproducible results.

About 30 years ago when American chemists jokinly commented that very soon there will no longer be frequent communication between Nigerian chemists and our foreign counterparts, the comment was ignored, parried away and discarded. Today that reality has come to stay. Nigerian scientists no longer communicate scientifically with their foreign or spe...

The antibacterial activity of compounds isolated from the stem bark and sawdust of Erythrophleum suaveolens were evaluated. Extraction of the pulverized plants materials was carried out using hexane, ethyl acetate and methanol. Extracts were fractionated using column chromatography and fractions were examined using Nuclear Magnetic Resonance spectr...

The four components present in the trypanocidal treatment Samorin, the commercially available formulation of isometamidium, were separated and purified by column chromatography. These compounds as well as the Samorin mixture and the other phenanthridine trypanocide, homidium, were tested on Trypanosoma congolense and wild type, diamidine- and isome...

Hibiscus sabdariffa (Malvaceae) is a plant that is widely recognised for its antihypertensive properties; however the constituent(s) responsible for this biological activity are presently unknown. The aim of this study was to identify the potential compounds that are responsible for the vasorelaxant activity of H. sabdariffa. Thereafter, the mechan...

Aim: Several medicinal uses have been reported for Anthocleista djalonensis and many types of pure compounds have been isolated. However, the anti-cancer activity of this plant has not been proven. The aim of this study was to screen for the phytochemicals present in the rootn-hexane, ethyl acetate, and acetone extracts of Anthocleista djalonensis,...

Twelve propolis samples from different parts of Libya were investigated for their phytochemical constituents. Ethanol extracts of the samples and some purified compounds were tested against Trypanosoma brucei, Plasmodium falciparum and against two helminth species, Trichinella spiralis and Caenorhabditis elegans, showing various degrees of activity...

Seeds of Monodora myristica and M. tenuifolia were extracted with hexane and the extracts were subjected to column chromatography, LC-MS and NMR analysis. In addition to masses of previously isolated compounds, other masses corresponding to unidentified compounds from the plants were detected. Using 2 D NMR techniques, one of the fractions from M....

Currently, the phytochemical and bioassay guided isolation of natural products requires more ingenious and strategic methods to obtain meaningful results. To the best of our knowledge, in Nigeria the absence of equipment and poor collaboration between chemists, biochemists, pharmacists, medical and veterinary doctors and those involved in natural p...