α-D-glucopyranosyl-(1→2)-[6-O-(L-tryptophanyl)-β-D-fructofuranoside]

Funding: K.K. wishes to thank the Centre for African Wetlands (CAW), University of Ghana, for providing seed funding to enable the collection of soil samples for microbe isolation and a TWAS Research Grant Award_17-512 RG/CHE/AF/AC_G. K.K. is also very grateful to the Cambridge-Africa Partnership for Research Excellence (CAPREx), which is funded by the Carnegie Corporation of New York, for a Postdoctoral Fellowship. K.K. also appreciates the Cambridge-Africa ALBORADA Research Fund for support and MRC African Research Leaders MR/S00520X/1 Award. S.K. wishes to thank the Carnegie BANGA-Africa Project Award for a PhD scholarship. Acknowledgments: All the authors extend their gratitude to the Department of Chemistry, UG for providing NMR facility. Conflicts of Interest: The authors declare no conflicts of interests. Author Contributions: K.K. collected mangrove plant parts and isolated the strain BRS2A-AR2. A.S.C. and M.C. identified the exact taxonomy of the strain. M.J. and H.D. provided access to facilities for mass spectrometry and data interpretation. K.K. performed chemical profiling to identify the major metabolite. S.K. and G.M.T. performed seed culture, large scale culture, isolation and purification of compound. A.K.D. performed all the biological assays. K.K. measured all NMR, IR and UV, analyzed the results and integration of data to give the complete structure of the compound. K.K. wrote the article.Peer reviewedPublisher PD

Paenidigyamycin g : 1-acetyl-2,4-dimethyl-3-phenethyl-1H-imidazol-3-ium

Author Contributions: K.K. and H.D. collected mangrove sediments and isolated the strain DE2SH. A.S.C. and M.C. identified the exact taxonomy of the strain after K.K. isolated DNA and whole genome sequenced the strain. M.J. and H.D. provided access to facilities for mass spectrometry and data interpretation. K.K. performed chemical profiling to identify the major metabolites. S.K., G.M.T. and T.M. performed seed culture, large scale culture, isolation and purification of compound. K.K. measured all NMR, IR and UV, analyzed the results and integration of data to give the complete structure of the compound. K.K., S.K. and G.M.T. wrote the initial draft of the article which was edited and finalized by all the authors. Funding: KK wishes to thank the Centre for African Wetlands (CAW), University of Ghana, for providing seed funding to enable the collection of soil samples for microbe isolation and a TWAS Research Grant Award_17-512 RG/CHE/AF/AC_G. K.K. is also very grateful to the Cambridge-Africa Partnership for Research Excellence (CAPREx), which is funded by the Carnegie Corporation of New York, for a Postdoctoral Fellowship. K.K. also appreciates the Cambridge-Africa ALBORADA Research Fund for support. K.K., H.D. and M.J. are grateful for this research which is jointly funded by the UK Medical Research Council (MRC) and the UK Department for International Development (DFID) under the MRC/DFID African Research Leaders Award (MR/S00520X/1). S.K. wishes to thank the Carnegie BANGA-Africa Project Award for a PhD scholarship and M.T. is grateful for an MPhil full scholarship from TWAS Research Grant Award_17-512 RG/CHE/AF/AC_G. Acknowledgments: All the authors extend their gratitude to the Department of Chemistry, UG for providing NMR facility. Conflicts of Interest: The authors declare no conflicts of interestsPeer reviewedPublisher PD

Mango anthracnose disease: the current situation and direction for future research

Mango anthracnose disease (MAD) is a destructive disease of mangoes, with estimated yield losses of up to 100% in unmanaged plantations. Several strains that constitute Colletotrichum complexes are implicated in MAD worldwide. All mangoes grown for commercial purposes are susceptible, and a resistant cultivar for all strains is not presently available on the market. The infection can widely spread before being detected since the disease is invincible until after a protracted latent period. The detection of multiple strains of the pathogen in Mexico, Brazil, and China has prompted a significant increase in research on the disease. Synthetic pesticide application is the primary management technique used to manage the disease. However, newly observed declines in anthracnose susceptibility to many fungicides highlight the need for more environmentally friendly approaches. Recent progress in understanding the host range, molecular and phenotypic characterization, and susceptibility of the disease in several mango cultivars is discussed in this review. It provides updates on the mode of transmission, infection biology and contemporary management strategies. We suggest an integrated and ecologically sound approach to managing MAD

Isolation and Antitrypanosomal Characterization of Furoquinoline and Oxylipin from Zanthoxylum zanthoxyloides

In the absence of vaccines, there is a need for alternative sources of effective chemotherapy for African trypanosomiasis (AT). The increasing rate of resistance and toxicity of commercially available antitrypanosomal drugs also necessitates an investigation into the mode of action of new antitrypanosomals for AT. In this study, furoquinoline 4, 7, 8-trimethoxyfuro (2, 3-b) quinoline (compound 1) and oxylipin 9-oxo-10, 12-octadecadienoic acid (compound 2) were isolated from the plant species Zanthoxylum zanthoxyloides (Lam) Zepern and Timler (root), and their in vitro efficacy and mechanisms of action investigated in Trypanosoma brucei (T. brucei), the species responsible for AT. Both compounds resulted in a selectively significant growth inhibition of T. brucei (compound 1, half-maximal effective concentration EC50 = 1.7 μM, selectivity indices SI = 74.9; compound 2, EC50 = 1.2 μM, SI = 107.3). With regards to effect on the cell cycle phases of T. brucei, only compound 1 significantly arrested the second growth-mitotic (G2-M) phase progression even though G2-M and DNA replication (S) phase arrest resulted in the overall reduction of T. brucei cells in G0-G1 for both compounds. Moreover, both compounds resulted in the aggregation and distortion of the elongated slender morphology of T. brucei. Analysis of antioxidant potential revealed that at their minimum and maximum concentrations, the compounds exhibited significant oxidative activities in T. brucei (compound 1, 22.7 μM Trolox equivalent (TE), 221.2 μM TE; compound 2, 15.0 μM TE, 297.7 μM TE). Analysis of growth kinetics also showed that compound 1 exhibited a relatively consistent growth inhibition of T. brucei at different concentrations as compared to compound 2. The results suggest that compounds 1 and 2 are promising antitrypanosomals with the potential for further development into novel AT chemotherapy

The role of tryptophan derivatives as anti-kinetoplastid agents

Kinetoplastids are the causative agents for a spectrum of vector-borne diseases including Leishmaniasis, Chagas disease and Trypanosomiasis that affect millions of people worldwide. In the absence of safe and effective vaccines, chemotherapy, in conjunction with vector control, remain the most significant control approach for kinetoplastid diseases. However, commercially available treatment for these neglected tropical diseases frequently ends up with toxic side effects and increasing resistance. To meet the rising need for innovative medications, alternative chemotherapeutic agents are required. Moreover, insights into target-based mode of action of chemotherapeutic agents are required if novel drugs that may outwit resistance to commercially available drugs are to be developed. Tryptophan has been implicated in a variety of diseases and disorders due to its fundamental role as a precursor to several bioactive metabolites, as well as its importance in the improvement of health and nutrition, diagnostics, and therapeutics. The regulation of tryptophan metabolism plays a fundamental role in the growth of kinetoplastids. Moreover, the levels of tryptophan may serve as a biomarker to distinguish between the stages of kinetoplastids making it an important amino acid to explore for drug targets. The main aim of this review is thus to provide a comprehensive literature synthesis of tryptophan derivatives to explore as potential anti-kinetoplastids. Here we highlight the role of tryptophan derivatives as chemotherapeutic agents against kinetoplastids. The reviewed compounds provide insights into potential new drug interventions that may combat the increasing problem of anti-kinetoplastid resistance

N-(Isobutyl)-3,4-methylenedioxy Cinnamoyl Amide

The plant Zanthoxylum zanthoxyloides (Lam.) Zepern. & Timler is one of the most important medicinal species of the genus Zanthoxylum on the African continent. It is used in the treatment and management of parasitic diseases in sub-Saharan Africa. These properties have inspired scientists to investigate species within the genus for bioactive compounds. However, a study, which details a spectroscopic, spectrometric and bioactivity guided extraction and isolation of antiparasitic compounds from the genus Zanthoxylum is currently non-existent. Tortozanthoxylamide (1), which is a derivative of the known compound armatamide was isolated from Z. zanthoxyloides and the full structure determined using UV, IR, 1D/2D-NMR and high-resolution liquid chromatography tandem mass spectrometry (HRESI-LC-MS) data. When tested against Trypanosoma brucei subsp. brucei, the parasite responsible for animal African trypanosomiasis in sub-Saharan Africa, 1 (IC50 7.78 µM) was just four times less active than the commercially available drug diminazene aceturate (IC50 1.88 µM). Diminazene aceturate is a potent drug for the treatment of animal African trypanosomiasis. Tortozanthoxylamide (1) exhibits a significant antitrypanosomal activity through remarkable alteration of the cell cycle in T. brucei subsp. brucei, but it is selectively non-toxic to mouse macrophages RAW 264.7 cell lines. This suggests that 1 may be considered as a scaffold for the further development of natural antitrypanosomal compounds

The Global Impact of COVID-19: Historical Development, Molecular Characterization, Drug Discovery and Future Directions

In December 2019, an outbreak of a respiratory disease called the coronavirus disease 2019 (COVID-19) caused by a new coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began in Wuhan, China. The SARS-CoV-2, an encapsulated positive-stranded RNA virus, spread worldwide with disastrous consequences for people’s health, economies, and quality of life. The disease has had far-reaching impacts on society, including economic disruption, school closures, and increased stress and anxiety. It has also highlighted disparities in healthcare access and outcomes, with marginalized communities disproportionately affected by the SARS-CoV-2. The symptoms of COVID-19 range from mild to severe. There is presently no effective cure. Nevertheless, significant progress has been made in developing COVID-19 vaccine for different therapeutic targets. For instance, scientists developed multifold vaccine candidates shortly after the COVID-19 outbreak after Pfizer and AstraZeneca discovered the initial COVID-19 vaccines. These vaccines reduce disease spread, severity, and mortality. The addition of rapid diagnostics to microscopy for COVID-19 diagnosis has proven crucial. Our review provides a thorough overview of the historical development of COVID-19 and molecular and biochemical characterization of the SARS-CoV-2. We highlight the potential contributions from insect and plant sources as anti-SARS-CoV-2 and present directions for future research