Suchergebnisse

Dr Ngbolua Koto-Te-Nyiwa is former Rector of the University of Gbado-Lite and Full Professor of Molecular Biology, Biochemistry and Biophysics at the University of Kinshasa in Democratic Republic of the Congo

Recent findings revealed that 90% of elephants are decreased, mainly due to hunting for ivory and the rapid expansion of human activities both in protected and non-protected areas including trans-boundary regions. Habitat fragmentation is also a problem faced by many species all over the world due to human activities. The aim this study is to carry out a survey on the movements and migration corridors of Loxodonta africana cyclotis in the Monzo Forest of Bosobolo Territory, Nord-Ubangi Province the Democratic Republic of the Congo. The present study was carried out into three steps: pre-survey (which consists in questioning the Territory Administrator, the heads of sectors and the supervisor of the Territorial Environment Service), survey (on 100 hunters and 100 farmers) and in situ biomonitoring to search elephant indices through the transect technique. The following parameters were taken into account in the survey: The presence of elephant (movement and migration corridors) via indices like dung density, field damage; the level of encounters with elephants; the migration season; the cause of extinction and regular migrations. Results revealed that the majority of respondents have over 5 years of experience in elephant hunting. Among these hunters 64.4% are active and 35.5% inactive. The main livelihood activity was agriculture (53.3%). 84.4% of the respondents encountered live elephants or their dung. The intense frequencies of elephant were observed from 1997 to 2002 while elephant disappearance was certified from 2002 to 2012 and the reappearance confirmed from 2012 to 2017 (90%). From 1997 to 2017, 16.6% of respondents thank that hunters killed 1 to 25 elephant heads while 14.4% of respondents reveal that hunters killed more than 100 heads during this period. The mobility is high in January and from June to December and moderate from February to May. The conservation of these mammals and their habitat would be of great importance, as elephants play a very important ecological role in the forests, ...

According to the WHO, more than 80% of the population in Africa resort to the traditional medicine for their health care. In the present study, a survey was carried out among traditional practitioners and the most cited plant species was submitted to anticancer experiments in vitro. The results revealed that Gardenia ternifolia contains secondary metabolites with anticancer activity and is selective towards breast (MCF-7) cancerous cell lines.

Recent findings indicate that the number of newborns with Sickle cell anemia (SCA) will increase on the horizon 2050. Among the concerned countries, Democratic Republic of the Congo will probably still be the country most in need of policies for the prevention and management of SCA. The present fundamental research was carried out with the aim of providing data to help future design and the development of new generation of techniques for the low cost diagnosis of SCA patients from low income countries. The interest in the protein thermal denaturation is due to its potential to easily quantify any change in the hemoglobin stability. The thermal denaturation of hemoglobin in human total blood samples was studied using molecular ultraviolet/visible absorption method. The result expressed as transition temperature (Tt) displayed the best discrimination between AA, AS and SS bloods at pH 7.40 and without ionic strength. Calculated values of Tt according to a non-linear regression analysis using the Gushimana Yav equation (a sigmoid plot) with the help of Microsoft Origin package are 65.2 ± 0.1 °C for AA blood, 61.0 ± 0.1 °C for AS blood and 58.0 ± 0.1 °C for SS blood. By considering Tt as a specific physical parameter, it is thus proposed to design and develop new generation of spectrophotometer for the biological diagnosis of SCA.

The search and development of antisickling herbal drugs constitute a priority agenda in Democratic Republic of the Congo (DRC), where Sickle cell anemia (SCA), one of the major public health problems affecting Africa, is endemic. The aims of our research program were (1) to identify plants traditionally used in folk medicine for managing SCA in DRC, (2) to identify other/new sources of antisickling bioactive secondary metabolites mainly from great apes pharmacopeia, (3) to validate their bioactivity, (4) to identify and elucidate the structures of the bioactive compounds/secondary metabolites and (5) to formulate a polyherbal medicine for managing SCA.

In Africa, about 80% of population relies on traditional medicine for their health care purpose. The aim of the present study was to evaluate the chemical composition of the plant species Pentadiplandra brazzeana Baill. used as dietary and medicinal plant by indigenous people in the Province of Nord-Ubangi and to provide update knowledge on phytochemistry and bioactivity of this plant species. A literature search was conducted to obtain information about the phytochemistry and pharmacognosy of Pentadiplandra brazzeana from various electronic databases (PubMed, PubMed Central, Science Direct and Google scholar). The scientific name of this plant species was used as a keyword for the search, along with the terms phytochemistry and pharmacognosy. The chemical structures of the P. brazzeana naturally occurring compounds were obtained from PCIDB (PhytoChemical Interactions DB) or drawn using ChemBioDraw Ultra 12.0 software package. Phytochemical screening revealed the presence of alkaloids, linked quinones, saponins, tannins and triterpenoids in both the leaves and roots. While anthocyanis, flavonoids and leuco-anthocyanins are present in the leaves but absent in the roots. Findings revealed that this plant is traditionally used in African folk medicine to treat various ailments including intestinal parasitic diseases and against Chlamydiae. The roots are used for food flour preservation. These roots smelling a raifort pungent odor are edible because of their sweet taste. The ethnopharmacological relevance of this plant species is due to the presence of sulfur-containing phytochemicals. The present study can, therefore, help inform future scientific research towards the development of novel drugs of relevance from P. brazzeana for the improvement of human health and wellbeing.

A forest inventory was conducted in two community-based forests in the Oubanguian eco-region from November 2016 to May 2017 to identify therapeutically valuable phytogenetic resources and traditional knowledge associated with their use. 269 medicinal plants belonging to 24 families and 26 species have been identified. Morinda morindoides (13.01%), Ricinodendron heudelotii (12.26%) and Triplochiton scleroxylon (10.40%) are the most common species in situ. However, species such as: Urena lobata (0.37%), Monodora myristica (0.37%) and Elaeophorbia drupifera (0.37%) are unfortunately becoming rare in the forest. Leaves (51.73%), bark (41.22%) and stems (0.74%) are the most commonly used. Anemia (22, 66%), sexual impotence (15.60%) and malaria as well as hemorrhoid (11.87 %.) are the most treated diseases. In order to protect plant biodiversity from human pressures, it is suggested the creation of a protected reserve to prevent species erosion and regulate access to these genetic resources in this eco-region for a sustainable development of community-based people.

A preliminary ecological study with a special emphasis on Non-timber forest products (NTFPs) was conducted between 2014 and 2015 on both anks of Lokame River in Lokame forest. The results showed that the Lokame natural forest has a very rich and diversified in NTFPs. Data collected over a total area of 2 ha identified 20 families and 25 different plant species producing NTFPs and 914 individuals, of which 39% are food, 38% for different uses, 14% for aphrodisiacs and 9% as medicinal. A comparison of data by region reveals that the left bank region is richer and more diversified than that of the right bank. Fruit is the most used organ (75%) followed by bark (60%) and leaves (50%). The unbarking is the most important collection technique for the entire study area with a frequency of 70%. The unbarking is followed by cutting down, collection, picking-up, thinning-out and uprooting. The collection by unbarking, uprooting and cutting down is destructive, henceforth these methods are not sustainable. The proportions of NTFPs collection are alarming for the conservation of Lokame forest area. It is therefore necessary to: (1) strengthen knowledge on NTFPs and sustainable management techniques associated with their exploitation, (2) develop and implement the NTFP-specific institutional and regulatory framework, (3) carry out economic diagnosis and control of the traceability of NTFP sectors, (4) strengthen institutional and human capacities for the development of the NTFP sector, and last (5) create a conducive environment in order to invest in the NTFP sector. Thus, Lokame natural forest will continue to play its role of biodiversity conservation and sustained production of natural resources.

Although bats carry out important beneficial ecological and agricultural functions such as pollination and dispersion of seeds, they often carry dangerous diseases. This is worrying because of the increased dependency of the urban populations in Kisangani on bats as a source of animal proteins. The straw-coloured fruit bat (Eidolon helvum) is one of the most notable bat species that is both important as a food source and as a host for zoonotic diseases. It is a widely distributed species, which is relatively common throughout its distribution area. Recently, it was classified as Near Threatened on the IUCN Red List due to a decreasing population trend. To evaluate the hunting pressure on this species and the supply of straw-coloured fruit bats for human consumption, we inventoried the carcasses of this species on one of the main bushmeat markets in the region of Kisangani, situated on the island of Maele. Our survey was carried out between January and December 2013 and targeted hunters as well as traders. In total, we counted 3,034 carcasses. Our preliminary results suggest that the hunting pressure on the straw-coloured fruit bat is rather stable. It is highest during the months of October, September and May and lowest in April and December. Our results do not show a decline in trade of these bats during August through November, when hunting is illegal in the DR Congo. This suggests that hunting activities are not ceased during that period. The fact that the local population consumes these bats on a regular basis throughout the year creates a very important opportunity for spill-over events that may lead to the outbreaks of zoonotic diseases.

Anthocleista liebrechtsiana is a plant species widely used in traditional medicine to treat bacterial infections. To provide a scientific basis to traditional uses of this plant species, it different extracts were evaluated for their antibacterial and antioxidant potential. Antibacterial activity was assessed using minimum inhibitory concentration. The presence of phytoconstituents was detected qualitatively. A. liebrechtsiana extracts displayed interesting antibacterial and antioxidant activities. The Gram positive bacteria S. aureus ATCC 33591 were more sensitive to Anthocleista liebrechtsiana than the Gram negative E. coli ATCC 27195. All the extracts tested were found to be biologically active against Staphyloccocus aureus except alcoholic extract of the leaves for which the bioactivity was moderate. The antibacterial activity was marked for the stem bark extracts (MIC ≤ 31.5 µg/mL) than those of the leaves (MIC ≤ 62.5 µg/mL). Methanol extract of A. liebrechtsiana displayed also interesting free radical Scavenging activity (IC50 < 10 µg/mL). Phytochemical analysis revealed the presence of total polyphenols, catechic tannins, alkaloids, saponins, terpenes and steroids. Antibacterial and free radical scavenging efficacy shown by this plant provides a scientific basis and thus, validates it traditional use as phytomedicine. Isolation and purification of different phytochemicals may further yield significant antibacterial and antioxidant agents.

Ebola Virus Disease (EVD) is an endemic zoonosis in tropical regions of Africa and Asia. Nowadays, this emerging and re-emerging disease is a serious public health problem. The present study was initiated to improve the level of knowledge and perception of the population on the EVD in Kinshasa. The survey was conducted among 254 households in Ngaba municipality located at Kinshasa city between 15 and 29 November 2014. The selection focused on this municipality is due to the fact that it was once hit by an epidemic. From identified among households, 249 were successfully surveyed, with a rate of 98%. Among the identified; we had 53.1% men and 46.9% women. It was noticed that 2% have never heard about EDV, 46.8% men and 39% women have a good knowledge of the EDV. Then 66.3% of the population would choose to call the health department if they were in front of a person with symptoms of EDV, and 98.8% perceive that the EVD is dangerous along with 67.9% are willing to help the Congolese authorities to educate the population to prevent it. Television was the most used source of information, either 88.4%. The present study highlights the lack of information and knowledge of the population in relation to the EVD. Many efforts are still required and significant investments are necessary for the dissemination of messages for the whole population. Such survey is reported for the first time in the Kinshasa city.

The emergence of mosquitos' resistance to synthetic insecticides constitutes a public health challenge in endemic areas. Insecticides of plant origin may serve as an alternative bio-control technique. The aim of this study was to evaluate the bioactivity of aqueous extracts of G. mangostana and S. zenkeri on Cx. quinquefasciatus larva. Larvicidal bioassays were carried out according to WHO protocol. The results showed that S. zenkeri is more larvicidal than G. mangostana. Aqueous extract of S. zenkeri displayed a very good larvicidal activity than G. mangostana with 90% mortality rate at 50% of extract dose after 24 hours exposure (LC50= 32.5 ± 5.8 mg/l and LC90= 47.7 ± 6.2 mg/l). The present finding indicates that selection of plant through zoopharmacognosy approach can serve as source of promising botanical mosquito control agents (which are biodegrade and environmentally no persistent) to be proposed as alternative to the conventional larvicides. For the best of our knowledge, this is the first report on the larvicidal activity of S. zenkeri from Democratic Republic of the Congo in the literature using Culex quinquefasciatus as model system.

Sickle cell disease (SCD) is an autosomal recessive type of hemoglobin disorder. Nowadays, the main challenge is how to improve the clinical aspects of life quality of the patients with low toxicity and safer therapy from indigenous knowledge. Democratic Republic of the Congo is one of the biodiversity rich countries in the world and can play the lead role in production and commercialization of standardized antisickling formulations like Drepanoalpha® worldwide. In this research paper, various methods of phytochemical standardization, such as TLC, HPTLC, HPLC, UV-Vis, IR, MS and their hyphenated techniques for profiling and quantification of markers compounds like phenolics (anthocyanins, flavonoids), phenolic and/or triterpenoic acids in Drepanoalpha®, a polyherbal medicine produced through a bio-guided based plant selection after eight years of intensive advanced laboratory research, are proposed for quality control and standardization feature.

Soybean (Glycine max L.) is a legume grown mainly for its seeds rich in proteins with the proportions of 36.5%. In Democratic Republic of the Congo (DRC or DR Congo), there are several varieties of cultivated soybeans. Since there is a diversity of soils cultivated by farmers, some varieties do not always express their potential. The reason why a study was conducted in N'djili-Brasserie crop scientific station from April20 to August12, 2013 for the first test and from October 2, 2013 to January 12, 2014 for the second test. This study was designed to compare the two used fertilizers, to bring out the best dose of these fertilizers enabling the farmers of this country to increase their production and to evaluate the yield of the variety TGX 888-49 C. The results of the test conducted according to a randomized complete block system with four repetitions showed that Stylosanthes guyanensis (6 Kg/m2) has positively influenced the studied parameters as well in the first test as in the second test of which the best yield was that observed from the first test (2133 Kg/ha) while the lowest yield was observed in the second test (1175 kg/ha). Given the findings, Stylosanthes guyanensis biomass can be retained and recommended as organic fertilizer for soybean production in Kinshasa and its surroundings.

Among the foodstuffs having a nutritional value in Democratic Republic of Congo (DRC), there is the corn crop. It is the second food crop after cassava with a high energetic value in calories and proteins. However, its production remains low in Kinshasa because of the poor quality of soil and less appropriate techniques for its production. It is therefore essential to define new more appropriate strategies in order to increase its availability locally. It is in this context that a study was conducted at the N'djili-Brasserie station for the purpose of assessing the effect of different legumes in crops associated with maize, and implementing technique of simple and adaptable production notably the QPM maize based association system and other food legumes that can play a key role in the soil fertility improvement. According to a randomized complete block system with four repetitions, the data collected were analyzed using the method of analysis of variance (ANOVA) with 5% likelihood point completed by the test of the least significant difference (LSD) to compare the different observed parameters. The findings indicate that T1 (QPMCorn + Peanut) and T2 (QPMCorn + Soybean) respectively influenced more vegetative parameters positively than the others. As for the estimated yields, the highest values were recorded in T1 (7.33 tons/ha) followed by T2 (7.03 tons/ha) and T3 (2.95 tons/ha) gave the lowest yield. To that end, T1 (QPM Maize + Groundnut) and T2 (QPM Maize + Soybean) can be kept and recommended to farmers in Kinshasa as varieties of associated crops focusing particularly on T1 (Peanut) for its effectiveness in nodulation and its relatively high yield.