Articles, Conference and Workshop Papers Collection

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Bacteriostatic and haemolytic activities of extracts and compounds of commiphora swynnertonii
(Research Journal of Pharmacognosy, 2023) Msengwa, Zaituni; Credo, David; Mafuru, Magesa; Mwesongo, James; Mabiki, Faith Philemon; Mwang’onde, Beda John; Mtambo, Madundo Mkumbukwa; Kusiluka, Lughano Jeremy; Mdegela, Robinson Hammerthon; Olsen, John Elmerdahl
Background and objective: Commiphora swynnertonii (Pax) is used in traditional medicine to treat infectious diseases. Previous studies have reported antimicrobial activity of this plant; however, the activity of compounds that are present in extracts of this plant has not been thoroughly documented. Likewise, the primary mode of action (bactericidal or bacteriostatic) and the possible toxicity on red blood cells have not been reported. Methods: Extracts of leaves, whole root, root bark, root wood, whole stem, stem bark and stem wood, were produced using hexane, dichloromethane, methanol and water. Cold and hot extraction methods were employed. Antibacterial activity of extracts was tested against selected medically important Gram-positive and Gram-negative bacteria by growth inhibition, minimum inhibitory concentrations and time kill assays. Moreover, haemolytic activity against sheep red blood cells was determined in vitro. Results: The hexane extracts of whole root and root bark, methanol extracts of root wood, and dichloromethane extracts from the leaves of C. swynnertonii inhibited the growth of S. aureus. MIC values for the extracts and compounds, indicated moderate activity against Gram-positive bacteria (Staphylococcus aureus, Streptococci species and Enterococci species) while the activity against Gram-negative bacteria (Escherichia coli, Klebsiella species, Pseudomonas aeruginosa, Salmonella species, Shigella sonnei and Yersinia enterocolitica) was weak. Time kill profiles showed the extracts have bacteriostatic activity against S. aureus, and low haemolytic effect, except for extracts of whole root and leaves at the concentration of 1000 μg/mL. Conclusion: Extracts of C. swynnertonii showed bacteriostatic activity against Gram-positive bacteria with low toxicity on red blood cells.
Seasonal variation of atmospheric composition of water-soluble inorganic species at rural Background site in Tanzania, East africa
(Ethiopian Journal of Environmental Studies and Management, 2010) Mkoma, S.L; Wang, W; Maenhaut, W; Tungaraza, C.T
Samples of coarse, fine and PM10 aerosols were collected at a rural Morogoro sites, during the 2005 dry season and 2006 wet season campaigns using a “Gent” PM10 stacked filter unit sampler with sequential Nuclepore polycarbonate filters. A total of 80 aerosol samples were analyzed for water-soluble inorganic ions components 2- + - - using Ion Chromatography. The mean concentration for the anions Cl , NO 3 , and SO 4 and the cations Na , + + 2+ 2+ NH 4 , K , Mg , Ca , showed seasonal variation in all size fractions with higher levels during the 2005 dry season campaign than the 2006 wet season campaign. The mean concentrations and associated standard deviation of 3 fine, coarse and PM10 mass were, 17±4, 52±27 and 69±29 μg/m during the 2005 dry season campaign and 3 2+ 13±5, 34±23 and 47±25 μg/m for the 2006 wet season campaign, respectively. Ca was the most important + 2- cation and the SO 4 was the main acidifying anionic component in PM10 while NH 4 was the most abundant - cation in the fine fraction and Cl the main anionic species in the coarse fraction. The ion balance ratios were all larger than 1.0; they range from 1.30 to 1.44 for the fine fraction and from 2.01 to 3.14 for the coarse fraction. The carbonates were not measured by Ion Chromatography therefore; these missing carbonates are thought to be largely responsible for the observed deviation from 1.0. The study suggests that primary sources such as soil dust dispersion and biomass burning made a significant contribution to the atmospheric particulate pollution in Morogoro.
Elemental composition and sources of atmospheric particulate matter in Dar es salaam, Tanzania
(Ethiopian Journal of Environmental Studies and Management, 2010) Mkoma, S. L; Tungaraza, C; Maenhaut, W; Raes, N
An intensive aerosol field campaign was carried out from 16 August to 16 September 2005 (dry season) at a kerbside in Dar es Salaam, Tanzania. A Gent PM 10 stacked filter unit sampler with coarse and fine Nuclepore polycarbonate filters, providing fine (0.4 μm) and coarse (8 μm) size fractions, was deployed. A total of 64 parallel collections were made. All samples were analysed for the PM mass by weighing. A further analysis was performed for 25 elements by particle-induced x-ray emission spectrometry. The PM 10 mass, as derived from the 3 stacked filter unit samples, was, on average, 58 μg/m . The concentrations of the heavy metals were lower than those for the elements of crustal origin. Nevertheless, some typical anthropogenic metals, such as Zn and Pb, exhibited much higher median PM 10 levels, suggesting strong local sources for these elements in Dar es Salaam. The results also showed very strong day/night differences for the crustal elements (Al, Si, Ca, Ti and Fe). Most elements exhibit strong correlations in the coarse size fraction and somewhat weaker ones in the fine size fraction suggesting that they may originate predominantly from the same source. Principal component analysis with VARIMAX rotation was applied to the data set. Five and four components were identified for the fine and coarse fractions and explained 86.5% and 90.8% of the variance in the data set respectively.
Urban dietary heavy metal intake from protein foods and vegetables in Dar es salaam
(International Journal of Biological and chemical science, 2011) Tungaraza, Clavery; Mato, Rubhera; Mkoma, Stelyus l; Ezekiel, Charles Nyarongo
This was an investigation to characterize seasonal and spatial distribution of particulate organic matter (POM) in the surface water of Lake Victoria at Speke Gulf, by using carbon-13 and nitrogen-15 isotopic signatures. Speke Gulf is under the influence of terrestrial inflow through river Simiyu. The POM from the lake surface water had higher C:N ratio values decreasing towards the deeper lake water, an indication of decreasing nitrogen content relative to carbonic materials. Samples away from the river mouth provided C:N ratios within the Redfield ratio range (C:N:P; 106:16:1) indicating materials of phytoplanktonic origin. The POM isotopes composition indicated a maximum δ 13 C value of −21.2‰ close to the river mouth and lowest value (~ −25‰) away from the river influence. The δ 15 N maximum (14.7‰) was observed near the river mouth with lower values (5.8‰) found in deeper waters away from the river mouth. Overall, there was a general decrease of 13 C and δ 15 N values from shallow water to deeper water. There was higher δ 15 N value dispersion (std. Dev. ±3.4‰) compared to δ 13 C values with std. Dev.±1.2‰. These values also varied with seasons, a phenomenon showing significant influence of land run off on the lake elemental distribution, carbon and nitrogen in particular.
Investigation of noise pollution in restaurants in Morogoro municipality, Tanzania, East Africa
(JASEM, 2009) Mkoma, Stelyus l; Tungaraza, Clavery; Samagwa, Dafrozah
The assessment of the present status of sound levels in seven restaurants at Morogoro municipality was studied. The indoor and outdoor ambient noise levels were measured twice a day, thrice a week for a period of two months by using digital sound level meter. In addition, questionnaires survey was used to assess sources of noise pollution in restaurants environment. The results show that the measured noise level in all studied restaurants ranged from 61dBA to 64dBA. The measured indoor noise levels were higher than outdoor in B-One, High Classic and Vyakula vya Asili restaurants and vise versa in Saddiq, Princes and Malindi dishes restaurants. The correlation coefficients between the indoors and outdoors locations in all the restaurants were either negative or less than 0.3 thus suggesting little or no impact of the indoor environment on the outdoor environment’s noise level. In comparison with permissible Tanzania Bureau of Standards the measured indoor ambient noise levels in the restaurants were higher than the maximum permissible standard limit of 55dBA for mixed residential zones. As for sources of noise pollution at Morogoro municipality, the study shows that people who visit restaurants to have a meal encounter three kinds of noise pollution: the noise created by other customers, the noise from outside (the street), and the noise provided by the music systems which are run in most restaurants. Therefore, proper planning for restaurants areas and other use zones is recommended @ JASEM
Isolation and toxicity evaluation of feruloyl ester and other triterpenoids from synadenium glaucescens pax
(The Journal of Phytopharmacology, 2022) Rwegoshora, Frank
The use of plants as sources of drug agents is attributed by factors among which are the easy accessibility to plants, less toxicity and little or no drug resistance. An improvement in both traditional medicine and drug discovery field necessitates investigation of pure compounds in any plant with medicinal value. Synadenium glaucescens Pax of the family Euphorbiaceae is among the medicinal plant in Tanzania which are proven to contain bioactive compounds against microbial infections. Analysis of ethanolic and methanolic extracts of root and stem barks respectively aided to isolated six pure compounds (SG1- 6). These compounds were analyzed by both 1D, 2D NMR and GC-MS while their spectral processing was achieved in the Bruker TopSpin 3.6.2. Among these compounds, one was a phenolic (hemicosanyl ferulate-SG1), three triterpenoids, (lupeol- SG2, epifriedelanol- SG4 and euphol- SG5), one steroid (β-sitosterol- SG6) and a long chain alkene (1-nonacosene- SG2). Cytotoxicity evaluation by Brine shrimp lethality test (BLST) indicated the compounds under report were practically non-toxic.
Ecotoxicity of mercury contaminated sediment collected from Mabubi river (Geita district, Tanzania) to the early life stages Of African catfish (clarias gariepinus)
(Elsevier, 2009) Chibunda, R.T; Pereka, A. E; Phiri, E.C.J; Tungaraza, C.
The quality of Hg contaminated sediments in artisanal gold mining areas of Tanzania have to date only been assessed through bulk chemical analysis. However, measurement of contaminant levels alone has a limited ability to predict adverse effects on living resources. In this study we investigated the possible effects of Hg contaminated sediments from the river Mabubi which drains the artisanal gold mine on the hatching success, larval survival and growth of the African catfish (Clarias gariepinus). The tested species is a resident fish whose demersal behaviour keeps it in frequent contact with the sediment. Sediments collected downstream of the mine decreased survival and impaired growth of Clarias gariepinus but did not affect its hatching success. These effects were observed up to six kilometres downstream of the mining activity. The calculated 5 d- LC 50 value (larval survival) was 1.75 μg/g Hg dw (95% CL of 0.72 – 2.53), the 5d-NOEC for hatching was >2.3 μg/g Hg dw and that for larval survival and growth was 0.23 μg/g Hg dw. In conclusion, chemistry and ecotoxicity results from this study suggest that sediments collected downstream of the mine adversely affect catfish and probably other fauna and as such present a considerable local environmental risk.
Social economic factors and malaria transmission in lower Moshi, northern Tanzania
(BioMed Central Ltd, 2022) Lowassa, Asanterabi; Mazigo, Humphrey D; Mahande, Aneth M; Mwang’onde, Beda J; Msangi, Shandala; Mahande, Michael J; Kimaro, Epiphania E; Elisante, Eliapenda; Kweka, Eliningaya J
Background: For many years social economic status has been used as an indicator to characterize malaria treatment seeking behaviors of communities and their adherence to malaria control programs. The present study was therefore conducted to assess the influence of household social economic status, knowledge, attitude and practice on treatment seeking behaviors, distance to health facilities and vector control measures in the Lower Moshi area, northern Tanzania. Methods: A cross-sectional household survey was carried out, a quantitative method was used to collect information from the households, and the household socio-economic status was estimated by employing a household asset-based approach. The structured questionnaire also collected information on malaria knowledge, attitudes and treatment seeking behaviors. Results: A total of 197 (68.8% were female) household heads were interviewed. Distance to the health centers influenced malaria treatment seeking behaviors especially for children (P = 0.001) and the number of visits to the health facilities made by the household members (P = 0.001). The head of the households' level of education had an influence on bed-net retreatment (P < 0.001) and acceptability of larval control programmes (P <0.001). Similarly, a significant association was observed between bed-net retreatment, larval control and occupation of the head of the household . Conclusion: Distance to the health centre influenced malaria treatment seeking behaviors, and the number of visits made by the household members. In addition, the education level of the household heads played a role in understanding and in the selection of malaria interventions for the households. Increasing the number of health facilities close to rural areas will improve malaria treatment seeking behavior, case management and hence reduce malaria-associated morbidities, especially in high risk groups.
Influence of bacterial activities on nitrogen uptake rates determined by the application of antibiotics
(Oceanologia, 2003) Tungaraza, Clavery; Brion, Natacha; Rousseau, Véronique; Baeyens, Willy; Goeyens, Leo
The influence of bacterial activities on inorganic nutrients has always affected total phytoplankton uptake rates owing to the absence of a reliable method that can exclude these effects. The use of natural samples to determine the contribution of bacterial activities has been based on the size fractionation method which, unfortunately, is encumbered with uncertainties, especially because of the size overlap between bacteria and phytoplankton communities. In this paper, the results are reported of an estimation of bacterial activities by the use of inhibitors (antibiotics). It was shown that the contribution of bacterial activities to the uptake of nitrogenous nutrients was highest for ammonium (79%), followed by nitrate (72%) and urea (62%). In a second set of experiments the concentration of ammonium was raised by 5 μM. This was done to avoid nutrient limitation resulting from the absence of recycled nutrients following the addition of antibiotics and the maximum contribution of bacterial activity to the uptake rate of ammonium increased to 87%. It can be concluded that the use of inhibitors is a good method, a reliable alternative to the fractionation method. However, it is important to note that inhibitors can affect both phytoplankton growth and the nutrient recycling process. Our results indicate that the application of antibiotics had measurable effects not only on the target bacteria but also on the uptake behaviour of phytoplankton. Our observations were therefore limited to the period when there was no effect on the phytoplankton, as was demonstrated by a carbon protein incorporation experiment.
Pre-sowing treatments to improve seed germination And seedling growth of commiphora swynnertonii (burrt.) and synadenium glaucescens (pax.)
(Academic Journals, 2023) Madege Richard, Raphael; Babu, Saidi; Mabiki, Faith Philemon; Mtui, Hosea; Kudra, Abdul
Medicinal and pesticidal plant propagation is hampered by poor seed germination due to seed dormancy. This study aimed to enhance seed germination and seedling growth using various pre- sowing treatments. A triplicated two-factor experiment in a Randomized Complete Block design was used. Soaking in water at 25°C for 24 h (T1), soaking in 60°C hot water for 10 min (T2), 10 ppm Potassium nitrate (KNO 3 ) treatment for 24 h (T3), 20 ppm Potassium nitrate (KNO 3 ) treatment for 24 h (T4), Treating seeds with Gibberellin (GA 3 ) solution at 250 ppm (T5), GA 3 Treating seeds with Gibberellin (GA 3 ) solution at 500 ppm for 72 (T6), Treating seeds with Gibberellin (GA 3 ) solution at 1000 ppm for 72 h (T7), and seeds without any pre-treatment were sown and used as control (T o ) on seed germination and seedling growth of two MPP species. The ability of a pre-sowing treatment to break seed dormancy was significantly dependent (p = 0.002) on the plant species. The effects due to interaction between pre- sowing seed treatment and plant species on seedling growth parameters (height, branches/shoot, leaves/shoot/, leaf area, fresh and dry weight) were significant (p < 0.05). These results provide the basis for the sustainable use of MPPs through propagation and conservation.
In-vitro assessment of antibacterial effects of combined crude extracts of s. glaucescens and c. swynnertonii with antibiotics
(Academic Journals, 2023) Ochollah, Mary George; Mabiki, Faith Philemon; Kusiluka, Lughano Jeremy Moses; Mdegela, Robinson Hammerthon; Olsen, John Elmerdahl
Currently, there is an upsurge of bacterial resistance in single-drug treatment regimens. This has stimulated a growing interest in research and development of new antibacterial agents containing several ingredients as one of the means to combat bacterial resistance. Herb-antibiotic combination therapy is one of the reported effective treatment regimens to combat antimicrobial resistance. This study was aimed to assess antibacterial effects of combined crude extracts of Synadenium glaucescens and Commiphora swynnertonii with antibiotics. In this study, three standard antibiotic drugs namely, ciprofloxacin, ampicillin and erythromycin in combination with crude extracts from S. glaucescens and C. swynnertonii were screened for antibacterial effects against two Gram-positive bacteria, Staphylococcus aureus and Enterococcus faecalis and three Gram-negative bacteria Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa. Broth microdilution technique was used to determine the Minimum Inhibitory Concentration (MIC) while Fractional Inhibitory Concentration (FIC) indices were calculated from MIC values of combined extracts to determine the combination effects. Synergism was observed when ciprofloxacin was combined with all tested crude extracts against E. coli (ΣFIC of 0.02), combination of ciprofloxacin with extract from root barks of C. swynnertonii (ΣFIC of 0.5) against S. aureus, root barks of Synadenium glaucescens (ΣFIC of 0.1) against S. aureus and combination of ampicillin with all tested crude extracts (ΣFIC of 0.03-0.1) against E. faecalis. Moreover, antagonism was observed between the combinations of ampicillin and erythromycin with all tested crude extracts against Gram-negative bacteria (ΣFIC of 4-8). Therefore, the combinations which demonstrated synergism may be promising alternatives for the treatment of infectious diseases caused by E. coli, S. aureus and E. faecalis. However, in the future, toxicity studies for combinations which demonstrated synergism are recommended.
Isolation and cytotoxicity evaluation of long chain bioactive compounds from commiphora swynnertonii (Burtt)
(Journal of Scientific and Innovative Research, 2022) Mabiki, Faith P; Machumi, Francis; Chacha, Musa
Commiphora swynnertonii (Burtt) is a medicinal plant with diverse traditional uses in Tanzania. However, there is limited information on isolation and cytotoxicity properties of bioactive compounds responsible for its pharmacological activities. Hence, this study attempted to isolate and assess toxicity properties of bioactive compounds from its leaves, stem barks and whole root. Isolation of bioactive compounds was done by column chromatography method. There structures were deduced with the aid of NMR and GC-MS data and comparison with spectral data available in the literatures. Cytotoxicity evaluation was done by brine shrimp lethality test (BSLT) method. Chromatographic separation led to isolation of Hexacosane (1), Ethyl octadecanoate (2) and Octacosanol (3) from the leaves; Ethyl pentadecanoate (4) and Hexacosanoic acid (5) from the stem barks and Ethyl tetradecanoate (6), Methyl pentadecanoate (7) and Ethyl hexadecanoate (8) from the whole root. BSLT evaluation revealed that all compounds were non-toxic to brine shrimp larvae (LC 50 >100 μg/ml). This study reports the isolation of these compounds for the first time from this plant, moreover, their presence demonstrates the usefulness of C. swynnertonii as a good source of pharmacological active reported compounds which authenticate its diverse uses in traditional medicine. Furthermore, the revealed non-toxic effect of these compounds shows safety and possibly its traditional use has no cytotoxicity effect. Yet, further studies on toxicity of these compounds are recommended.
Effect of changes in business environments on traded medicinal plants products in Tanzania: an explorative study
(Heliyon, 2022) Mpelangwa, Eziacka Mathew; Makindara, Jeremia Ramos; Sorensen, Olav Jull; Bengesi, Kenneth Michael Kitundu; Mabiki, Faith Philemon
In Tanzania, a complex rural to urban supply network for the medicinal plants' products trade has developed over time driven by changes in business environments at the macro level notably in the policy and regulatory frameworks and the micro level resulting from traders’ reactions and responses to those changes and pandemics. These changes in business environments and responses of traders have shaped the current trade practices. However, the response of traders to changes in business environments and the evolutionary paths over time are not well documented. Therefore, this paper aimed to synchronize changes in business environment over time and empirically determine how the trade has evolved concerning the responses of the medicinal plants' traders in Tanzania. The study applied economic evolution theory to describe the interactions of changes in business en- vironments and responses of traders to demarcate the evolutionary stages. Primary data were collected from traders, regulators, and researchers through ten focus group discussions and sixteen in-depth interviews from five regions of Tanzania. The results indicated that the traders of medicinal plant products responded by improving product appearance and modernizing both practices and business premises. The study findings have identified four evolutionary stages of trade in medicinal plant products in Tanzania: The first stage was the colonial era (1882–1961), the second is the government supremacy era (1961–1984), the third is the emergence of the private sector era (1985–2004), and the fourth is the market and regulation integration era (started in 2005). Moreover, because of the partial implementation of the regulatory framework, the fifth stage of trade evolution is also ex- pected. This stage is expected to be demarcated when the regulatory framework and market forces work together. Therefore, the study recommends that proper enforcement measures be put in place to ensure desired results whenever there are changes in business environments in traditional medicines practice. This is due to the expectation of the fifth stage whereby one of its characteristics is stiff competition among traders and which will require robust business models to survive in business.
Epifriedelanol is the key Compound to antibacterial Effects of extracts of synadenium glaucescens (pax) against Medically important bacteria
(Frontiers, 2023) Msengwa, Zaituni; Rwegoshora, Frank; David, Credo; Mwesongo, James; Mafuru, Magesa; Mabiki, Faith P; Mwang’onde, Beda J; Mtambo, Madundo M; Kusiluka, Lughano J. M; Mdegela, Robinson H; Olsen, John E
Introduction: Synadenium glaucescens has been used for the treatment of bacterial infections in many parts of the world. We investigated the antibacterial and cytotoxicity activities of secondary metabolites of this plant. Methods: Hexane, dichloromethane, methanol, and water were used as extraction solvents. The extract of the root bark was fractionated with ethyl acetate and methanol. The isolation of compounds from root barks, leaves and stem wood extracts were carried out using column chromatography. Antibacterial activities were characterized based on growth curves, killing curves and MIC determinations. Haemolytic effect towards sheep red blood cells (RBCs) was analysed with spectrophotometer at the wavelength of 540nm. Results and Discussion: Extracts from whole root and root bark showed strong activity against Staphylococcus aureus, and Streptococci and Enterococci species, and moderate to weak activity against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella species, Shigella sonnei and Yersinia enterocolitica. Staphylococcus aureus was the most susceptible, and E. coli and Klebsiella pneumonia were the least susceptible ones. Likewise, extracts, fractions, sub-fractions and epifriedelanol demonstrated bacteriostatic activity against S. aureus. The haemolytic activity of the extracts, fractions, sub-fractions and epifriedelanol was significantly low compared to the positive control, hydrogen peroxide. But extract from leaves showed high haemolytic effects at the concentrations of 500 mg/mL and 1000 mg/mL. Thus, extracts of S. glaucescens have antibacterial activity against several Gram-positive bacteria including Methicillin Resistant S. aureus with low haemolytic activity. At high concentrations, the extracts from leaves have toxicity risk. More studies for the active compounds are required for biological testing.
In vitro antibacterial potential of extracts of sterculia Africana, acacia sieberiana, and cassia abbreviata ssp. abbreviata used by yellow baboons (papio cynocephalus) for possible self-medication in Mikumi national park, Tanzania
(Hindawi, 2018) Kirabo, Irene; Mabiki, Faith P; Mdegela, Robinson H; Obbo, Christopher J. D
In the animals in general and nonhuman primates in particular self-medication has been widely reported; however, little is still known about the pharmacological activity of the extracts present in their daily diet. The in vitro antibacterial activity of the stem, root bark, and leaf extracts of three selected plants on which yellow baboons feed in an unusual manner in Mikumi National Park, Tanzania, was evaluated. Crude plant extracts were tested against Gram positive and Gram negative bacteria of medical and veterinary importance employing a modified agar well diffusion method and Minimum Inhibitory Concentration (MIC) technique. The lowest MIC value for Gram positive strains was 0.31 mg/ml demonstrated by Cassia abbreviata ssp. abbreviata against Staphylococcus aureus (ATCC 25923). The highest susceptibility to the ethanol plant extracts was exhibited by Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus, examples of microbes that affect both human and nonhuman primates. These findings demonstrate that the plant extracts from Sterculia africana, Acacia sieberiana, and Cassia abbreviata ssp. abbreviata have antibacterial activity and may be used as feed for their prophylactic benefits. Remarkably, the lowest MIC of 0.16 mg/ml was only 16-fold weaker than Gentamicin, a standard drug.
Isolation and identification of long -chain aliphatic compounds from synadenium glaucescens
(The Journal of Phytopharmacology, 2022) Nyigo, Vitus A; Malebo, Hamisi M; Mabiki, Faith; Mdegela, Robinson
Purification of dichloromethane extract from root barks and leaves of Synadenium glaucescens extracts through chromatographic techniques resulted into the isolation of two compounds, namely erythrinacinate C and 1-octacosanol. Chemical structures were established mainly using both one and two dimensional 1H and 13C NMR data and by comparison of the current NMR data with those from literature. Mass spectrophotometry data were used for confirmation through molecular ion peak. Both compounds are known to have been isolated from other plant species but are being reported from this plant species for the first time.
Thin layer chromatographic method for detection of conventional drug adulterants in herbal products
(MDPI, 2022) Mwankuna, Christopher Johnson; Mariki, Eliapenda Elisante; Mabiki, Faith Philemon; Malebo, Hamisi Masanja; Styrishave, Bjarne; Mdegela, Robinson Hammerton
Commercially available conventional drugs have been used to adulterate herbal products. Considering the rapid growth of herbal products’ market, it is essential to screen herbal products for the presence of conventional drugs. Simple analytical methods are needed for the rapid screening of conventional drugs that are likely to be adulterated in herbal products. Thin layer chromatography (TLC) methods for screening twelve conventional drugs in herbal products have been developed and applied. The analytes were extracted from herbal products using acetonitrile:methanol:acetic acid:water (4:4:1:1, v/v). Solvent mixture of dichloromethane:ethyl acetate:methanol (75:15:10, v/v) separated well trimethoprim, sildenafil, paracetamol, and sulfamethoxazole while pyrimethamine, metronidazole, and sulfadoxine were well separated by dichloromethane:ethyl acetate:methanol (77.5:12.5:10, v/v). In addition, acetyl salicylic acid, ibuprofen, diclofenac, quinine, and lumefantrine were well separated by ethyl acetate:methanol:30% ammonia (75:22.5:2.5, v/v). Chromatographic separations were found to be highly reproducible, and more than 10 samples can be analysed in one run. The method was applied in the screening of 229 herbal products. Consequently, 24.0% of the samples contained one adulterant, while 21.4% contained at least two adulterants. All conventional drugs detected in herbal products were not mentioned on the labels and therefore the consumers are kept unaware of their side effects and health problems. Further studies for confirming and quantitatively determining the adulterants in a wide range of products as well as a systematic toxicological analysis of the adulterants in herbal products are recommended.
Antibacterial effects of single and combined crude extracts of synadenium glaucescens and commiphora swynnertonii
(2022) Ochollah, G, Mary; Olsen, E, John; Mdegela, H, Robinson; Kusiluka, J.M, Lughano; Mabiki, P, Faith; Msengwa, S, Zaituni
Background: Synadenium glaucescens and Commiphora swynnertonii are among the reported plants used traditionally for treatment of bacterial infections. This study reports antibacterial effects of single and combined extracts from leaves, stem and root barks of Commiphora swynnertonii and Synadenium glaucescens. Materials and Methods: Plants were collected from Manyara and Njombe regions in Tanzania. Extraction was done using dichloromethane and methanol. The extracts were assessed for antibacterial activity against Gram-positive bacteria (Staphylococcus aureus and Enterococcus faecalis) and Gram-negative bacteria (Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa). Minimum Inhibitory Concentrations (MIC) was determined by broth microdilution, while Fractional Inhibitory Concentration (FIC) indices were calculated from MIC values of combined extracts to determine combination effects. Results: Strong antibacterial activities were demonstrated by all extracts of S. glaucescens (MIC 0.011-0.375mg/mL) against Gram-positive bacteria and methanol extracts of C. swynnertonii (MIC 0.047-0.375mg/mL). Synergistic effect was observed when combining methanol extracts of C. swynnertonii stem bark with S. glaucescens leaves against S. aureus (∑FIC 0.5), Other synergistic effects were observed against E. faecalis with dichloromethane extracts of C. swynnertonii stem bark and S. glaucescens stem bark (∑FIC 0.5), and C. swynnertonii root bark and S. glaucescens root bark (FIC index 0.3). For the remaining combinations, mainly additive effects were observed. Conclusion: Synergistic effects on bacteria were observed by combining different plant parts of S. glaucescens and C. swynnertonii suggesting that it could be beneficial to combine such extracts when used for antibacterial purposes.
PCDD/F and Dioxin-Like PCB determinations in Mtoni estuarine sediments (Tanzania) using the chemically activated luciferase gene expression (CALUX) bioassay
(Canadian Center of Science and Education, 2013-03-19) Mihale, Matobola J.; Croes, Kim; Tungaraza, Clavery; Baeyens, Willy; Van Langenhove, Kersten
Sediments from Mtoni estuary and 2 tributaries, Tanzania, were screened for polychlorinated-p-dibenzodioxins, -dibenzofurans (PCDD/Fs) and dioxin-like PCBs (dl-PCBs) using the chemically activated luciferase gene expression (CALUX) bioassay approach. PCDD/Fs expressed as bio analytical equivalence (BEQ) values ranged from 5.7 ± 1.4 to 39.9 ± 5.8 pg BEQ/g sediment in the wet season and from 14.1 ± 2.0 to 32.8 ± 4.7 pg BEQ/g sediment in the dry season, with higher levels observed in Kizinga River and stations close to the mouth of that river. Dioxin-like PCB levels ranged from 0.21 ± 0.03 to 0.53 ± 0.03 pg BEQ/g sediment in the wet season and from 0.22 ± 0.03 to 0.59 ± 0.04 pg BEQ/g sediment in the dry season. Higher PCDD/F and dl-PCB levels in sediments are probably related to open burning of plastic scraps, household burning of wood or charcoal and traffic related emissions, all of which occur in the Dar es Salaam region. The denser population and the more intense industrial activities in the Kizinga River basin may explain the enhanced PCDD/F and dl-PCB levels observed in the sediments of that river compared to the levels in the Mzinga River basin. A third sampling campaign, including also stations in the downstream estuary, confirmed the enhanced levels in the Kizinga River (maximum of 400 pg-BEQ/g) and also showed that a clear decreasing concentration gradient in the downstream direction exists. It cannot be excluded that the levels of these pollutants in the sediments of the Mtoni estuary pose a threat to the local biological community.
Implementation report of research project: adaptation strategies for challenges associated with climate and ecological changes affecting lake victoria communities
(United National Institute for Training and Research, 2015) Tungaraza, Clavery; Eliapenda, Elisante; Osewe, Kajitanus O.; Palapala, Paul M.

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