Nature-inspired synthesis of antibacterial glucovanillin derivatives.

The ongoing threat of Antimicrobial Resistance (AMR) complicated by the rise of Multidrug-Resistant (MDR) pathogens calls for increased efforts in the search for novel treatment options. While deriving inspiration from antibacterial natural compounds, this study aimed at using synthetic approaches to generate a series of glucovanillin derivatives and explore their antibacterial potentials. Among the synthesized derivatives, optimum antibacterial activities were exhibited by those containing 2,4- and 3,5-dichlorophenylamino group coupled to a glucovanillin moiety (compounds 6h and 8d respectively). In those compounds, the Minimum Inhibitory Concentrations (MIC) of 128-256 µg/mL were observed against reference and MDR strains of Klebsiella pneumoniae, Methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium (VRE). Moreover, these findings emphasize the claims from previous reports on the essence of smaller molecular size, the presence of protonatable amino groups and halogens in potential antibacterial agents. The observed moderate and broad-spectrum activities of the stated derivatives point to their suitability as potential leads towards further efforts to improve their antibacterial activities.

Isolation and Characterization of Galloylglucoses Effective against Multidrug-Resistant Strains of Escherichia coli and Klebsiella pneumoniae.

The search for new antibiotics against multidrug-resistant (MDR), Gram-negative bacteria is crucial with respect to filling the antibiotics development pipeline, which is subject to a critical shortage of novel molecules. Screening of natural products is a promising approach for identifying antimicrobial compounds hosting a higher degree of novelty. Here, we report the isolation and characterization of four galloylglucoses active against different MDR strains of Escherichia coli and Klebsiella pneumoniae. A crude acetone extract was prepared from Paeonia officinalis Linnaeus leaves, and bioautography-guided isolation of active compounds from the extract was performed by liquid-liquid extraction, as well as open column, flash, and preparative chromatographic methods. Isolated active compounds were characterized and elucidated by a combination of spectroscopic and spectrometric techniques. In vitro antimicrobial susceptibility testing was carried out on E. coli and K. pneumoniae using 2 reference strains and 13 strains hosting a wide range of MDR phenotypes. Furthermore, in vivo antibacterial activities were assessed using Galleria mellonella larvae, and compounds 1,2,3,4,6-penta-O-galloyl-ß-d-glucose, 3-O-digalloyl-1,2,4,6-tetra-O-galloyl-ß-d-glucose, 6-O-digalloyl-1,2,3,4-tetra-O-galloyl-ß-d-glucose, and 3,6-bis-O-digalloyl-1,2,4-tri-O-galloyl-ß-d-glucose were isolated and characterized. They showed minimum inhibitory concentration (MIC) values in the range of 2-256 µg/mL across tested bacterial strains. These findings have added to the number of known galloylglucoses from P. officinalis and highlight their potential against MDR Gram-negative bacteria.

Reproducibility challenges in the search for antibacterial compounds from nature.

BACKGROUND: Reproducibility of reported antibacterial activities of plant extracts has long remained questionable. Although plant-related factors should be well considered in serious pharmacognostic research, they are often not addressed in many research papers. Here we highlight the challenges in reproducing antibacterial activities of plant extracts. METHODS: Plants with reported antibacterial activities of interest were obtained from a literature review. Antibacterial activities against Escherichia coli and Klebsiella pneumoniae were tested using extracts' solutions in 10% DMSO and acetone. Compositions of working solutions from both solvents were established using LC-MS analysis. Moreover, the availability of details likely to affect reproducibility was evaluated in articles which reported antibacterial activities of studied plants. RESULTS: Inhibition of bacterial growth at MIC of 256-1024 µg/mL was observed in only 15.4% of identical plant species. These values were 4-16-fold higher than those reported earlier. Further, 18.2% of related plant species had MICs of 128-256 µg/mL. Besides, 29.2% and 95.8% of the extracts were soluble to sparingly soluble in 10% DMSO and acetone, respectively. Extracts' solutions in both solvents showed similar qualitative compositions, with differing quantities of corresponding phytochemicals. Details regarding seasons and growth state at collection were missing in 65% and 95% of evaluated articles, respectively. Likewise, solvents used to dissolve the extracts were lacking in 30% of the articles, whereas 40% of them used unidentified bacterial isolates. CONCLUSION: Reproducibility of previously reported activities from plants' extracts is a multi-factorial aspect. Thus, collective approaches are necessary in addressing the highlighted challenges.

Harmonization of medical products regulation: a key factor for improving regulatory capacity in the East African Community.

BACKGROUND: Limited capacity to regulate medical products is associated with circulation of products which do not meet standards of quality, safety and efficacy with negative public health and economic outcomes. This study focused on assessing the effect of the East African Community (EAC) medicines regulatory harmonization initiative on the capacity of national medicines regulatory agencies, with a focus on registration and inspection systems. METHODS: An exploratory mixed-method design using both qualitative and quantitative data to access data from six national medicines regulatory authorities (NMRAs) and the EAC Secretariat. Data was collected using a combination of semi-structured interviews, questionnaires, and checklists for the period 2010/11-2015/16 with 2010/11 data serving as baseline. Heads of NMRAs, regulatory and monitoring and evaluation experts, and the EAC Secretariat Project Officer were enrolled in the study. A set of 14 indicators grouped into 6 categories were used to assess NMRAs performance. RESULTS: Policy and legal frameworks provide a foundation for effective regulation. Collaboration, harmonization, joint dossier reviews and inspections of manufacturing sites, reliance and cooperation are key factors for building trust and capacity among NMRAs. Five out of six of the EAC Partner States have comprehensive medicines laws with autonomous NMRAs. All the NMRAs have functional registration and good manufacturing practice inspection systems supported by regional harmonised guidelines for registration, inspection, quality management and information management systems with four NMRAs attaining ISO 9001:2015 certification. CONCLUSIONS: The EAC regulatory harmonization initiative has contributed to improved capacity to regulate medical products. The indicators generated from this research can be replicated for evaluation of similar initiatives across and beyond the African continent and contribute to public health policy.

Comparison of extraction efficiency and selectivity between low-temperature pressurized microwave-assisted extraction and prolonged maceration.

Extraction is a key step in studying compounds from plants and other natural sources. The common use of high temperatures in pressurized microwave-assisted extraction (PMAE) makes it unsuitable for the extraction of compounds with low or unknown thermal stability. This study aimed at determining the suitability of low-temperature, short-time PMAE in attaining yields comparable to those of prolonged maceration at room temperature. Additionally, we explored the phytochemical differences of the extracts from both techniques. Maceration at room temperature for 24 hr and PMAE at 40-45°C and 10 bar for 30 min were carried out on 18 samples from 14 plant species at a solvent-to-feeds ratio of 10. The PMAE yields of 16 out of 18 samples were within the proportions of 91-139.2% as compared with the respective extracts from maceration. Varying numbers of nonmatching peaks were noted in MS chromatograms of five extract pairs, indicating selective extraction of some compounds. Low-temperature PMAE can attain reasonable extraction efficiency with the added value of sparing compounds of low thermal stability. The method can also enable the recovery of compounds distinct from those obtained by maceration.

National medicines regulatory authorities financial sustainability in the East African Community.

INTRODUCTION: Adequate and sustainable funding of national medicine regulatory agencies (NMRAs) is key for assurance of quality, safety and efficacy of medical products circulating in a market. The study aimed to determine factors affecting NMRAs funding in five East African Community (EAC) countries namely: Burundi, Kenya, Rwanda, Tanzania (Mainland and Zanzibar) and Uganda. METHODOLOGY: An exploratory, mixed method design using both qualitative and quantitative data, was employed. Data from six NMRAs was collected through a combination of semi-structured interviews, questionnaires, and checklists for the period 2011/12-2014/15 while 2010/11 data served as baseline. Interviews were conducted with heads of NMRAs and monitoring and evaluation experts of the respective agencies. NMRA's financing was assessed using six indicators namely, funding policy, financial autonomy, the total annual budget, actual funding per annum, funds received from various sources, and the NMRA expenditure. RESULTS: The average total annual budget for all the EAC countries during the study period 2011-2015 ranged from USD 824,328.67 to USD 10,724,536.50. The low budget in Zanzibar may be attributed to population and pharmaceutical market size. Uganda's attainment of 98.75% (USD 10,656,704) revenue from industry fees is a result of deliberate government policy change from 100% reliance on donor funding over a period of 10 years (1995-2015). On average, the proportion of revenue against budget per annum is 54.8% (USD 458,970.11), 98.7% (USD 10,302,295.25) and 100% (USD 7,375,802.08) for Zanzibar Food & Drugs Agency (ZFDA), Uganda National Drug Authority (NDA) and Tanzania Medicines and Medical Devices Authority (TMDA) respectively. Governments, industry fees and donors are the major sources of funding across all NMRAs in the EAC region, with TMDA and Uganda NDA relying more on industry fees by 73.20% (USD 4,664,777.59) and 98.25% (USD 8,077,238.20) respectively. While Burundi relies solely on government funding, ZFDA, on the other hand, received on average 50.40% (USD 252,557.22) from government and 40.60% (USD 165,303.34) from industry fees and the remaining 9% from donors and other sources. An overall contribution of funds received from donors by each NMRA was the least among other sources of financing. Observation of expenditure patterns indicated operational costs to be the major expense in the majority of the NMRAs, followed by salaries and infrastructure development. The Kenya NMRA has the highest degree of average expenditure across all three categories, with the least average expenditures being marked by Burundi NMRA. The operational costs on average increased considerably in all the NMRAs during the study period. CONCLUSION: Evidence from the EAC suggests that government and industry fees are the main sources of funding while donor contributions vary from country to country. Government policy, legal framework, and fees structure are the key enablers of NMRAs funding sustainability.

Conformity of package inserts information to regulatory requirements among selected branded and generic medicinal products circulating on the East African market.

BACKGROUND: Availability of correct and adequate information about medicines is an important aspect in ensuring rational use of medicines and hence facilitating safety and expected efficacy of medicines during therapy. Package inserts have proven to be a good source of information to the prescribers and patients whereby they have been useful in highlighting important information pertaining proper use and handling of the medicines. The present study was aimed at establishing the extent to which package inserts of medicines circulating on the markets of the East African Community (EAC) Partner States conform to medicines information requirements as established in the harmonized guidelines as well as national guidelines. METHODS: A total of 99 package inserts from six (6) types of medicines namely Albendazole, Artemether/Lumefantrine (ALu), Ciprofloxacin, Paracetamol, Amoxicillin and Metronidazole were purposefully collected from three EAC Partner States: Kenya, Tanzania and Uganda. The medicines were selected based on their indications as first line treatments, high rates of utilization within the medicines supply system and their positions in treatment of diseases of public importance across EAC Partner States. The inserts were evaluated on the availability of information regarding fifteen (15) parameters as extracted from the EAC harmonized guidelines for registration of medicines. Moreover, comparisons were made between the percentage conformity of the branded versus generic products, markets from which the samples were collected, origin of the manufacturer and type of medicine. RESULTS: Majority (93.9-100%) of the medicines' package inserts highly conformed to the inclusion of the information regarding the description and composition of the medications, indications, dosage and methods of administration, warnings and precautions, contraindications and storage conditions. However, the information on handling and disposal, container package description, excipients used, clinical pharmacology of the medicines, and directions regarding overdose ranked the least in conformance with conformity ranging from 13.1-52.5%. The parameter with the lowest observed percentage conformity among the branded products scored 50% as compared to 10.8% among the generic products. Moreover, there was no significant difference (P<0.05) in the percentage conformity of the package inserts collected from each of the three Partner States as compared to the average from studied medicines. A generally good conformity was observed among medicines manufactured by European based manufacturers as compared to those based in Asia and EAC Partner States. In addition, PIs of Albendazole, Ciprofloxacin, Amoxicillin and Artemether/Lumefantrine did show overall high conformity across most of the product information requirements. CONCLUSION: Our study revealed the existence of a significant number of medicinal products circulating on the markets of EAC Partner States without necessary compliance with all product information requirements. We therefore recommend that NMRAs ensure thorough pre-market assessment of product information as well as strengthening their post marketing surveillance to ensure that medicines circulating on the market comply to medicines information requirements at all times. Emphasis should also be given to manufacturers on the importance of inclusion of appropriate and adequate product information for the safety of patients, including advocating for inclusion of patient-friendly and easy to understand medicines information.