n-Alkane bound biomarker fingerprints from asphaltenes in the bitumens of Eastern Dahomey Basin, Nigeria: Source and genetic implications

The asphaltene fractions of the bitumens of Eastern Dahomey Basin in Nigeria, were analyzed by flash pyrolysis-gas chromatography (Py-GC) method in order to unravel its geochemical history and properties. The distributions of the initial biomarkers of the original oils from the pyrolysates are related to the assessment of organic matter source, paleo-redox conditions and source environment during deposition. Also, it effectively establishes the genetic relationship of the bitumens. The n-alkane distributions in the pyrolysates reveal nC$_9$-nC$_{32}$ n-alkanes, maximizing at nC$_{14}$, isoprenoids-pristane (Pr) and phytane (Ph), and some n-alkene peaks. High peaks of low to medium-weight nC$_9$-nC$_{20}$ n-alkanes and low peaks of nC$_{21}$+ n-alkanes characterize the distributions. These reveal that abundant algal organic matter with some terrigenous inputs contributed to the source rock of the bitumens. The high concentration of marine organic matter inputs to the source rock is further confirmed by the nC$_{17}$/nC$_{27}$ ratios which range from 5.39 to 19.82 and shows the predominance of nC$_{17}$ alkanes. The general unimodal n-alkane distributions in the bitumens indicate derivation from similar organic matter types showing that they are genetically related. The anoxic to suboxic environmental conditions that prevailed during the deposition of the sediments is revealed by the isoprenoids, Pr/Ph ratios (0.72–1.28). Pristane/nC$_{17}$ and Phytane/nC$_{18}$ range from 0.16 to 0.33 and 0.22 to 0.56, revealing that the bitumens were from predominantly marine organic matter (type II kerogen) preserved in a reducing environment with no evidence of biodegradation. However, the Ph/nC18 ratio and the cross plot of Pr+Ph/nC17+nC18 allow the classification of the bitumens into two subfamilies/groups (A and B). The bitumen samples have low wax content as indicated by the degree of waxiness ranging from 0.21 to 0.38 which confirms low terrigenous input. Based on the carbon preference index (CPI: 0.92 to 1.55) and odd-even predominance (OEP: 0.70 to 1.36), it is concluded that the bitumens are immature to marginally mature

Traditional medicine use during pregnancy and labor in African context: A scoping review

Traditional medicine (TM) has been more popular among pregnant women worldwide and has played a significant part in maternal health-care services in many nations. Herbs, herbal preparations, and finished herbal products all contain active substances that are derived from plant parts or other plant components that are thought to have medicinal advantages. To diagnose, prevent, and treat illnesses as well as to enhance general well-being, about 80% of people use a variety of TM, including herbal remedies. A systematic search of Google Scholar and PubMed was performed utilizing an established scoping review framework by Joanna Briggs Institute from January 2012 to December 2022. A consequent title and abstract review of articles published on TM in the African context were completed. Of over 15,000 published studies identified, 15 meeting the inclusion criteria were integrated into the following seven categorical themes: prevalence of TM use, source of information on TM use, reasons for use of TM, route of administration, common herbs used in pregnancy and labor, the effect of herbs used in pregnancy and labor, and predictors of use of TM. The studies reviewed were primarily in the context of an African setting on the use of TM regarding herbal medicine. Of all the articles, the highest number of studies was conducted in Zimbabwe. This review shows increased use of TM by women during pregnancy and labor with a reported prevalence rate varying from 12% to 60%. However, a decrease in use in the third trimester of pregnancy was reported. The most frequent source of information on the use of TM was from family and friends, while age, parity, education, and income were factors affecting use. In conclusion, the participants do not often disclose the use of TM during their antenatal attendance and the reason for use was accessibility and cost. Therefore, there is a need for further study on the safety and efficacy of TM use in pregnancy and labor