Phragmanthera capitata was reported to possess many biological properties making it a good candidate for the formulation of a phytomedicine with multiple effects. In this work, we studied some factors likely to modify these therapeutic properties with the aim to contribute to its standardization as an improved traditional medicine. P. capitata parasitizing Persea americana, Psidium guajava, and Podocarpus mannii were harvested at three phenological stages (vegetative, flowering, and fruiting stages). The extracts were prepared by maceration in n-hexane, ethyl acetate, ethanol, methanol, and distilled water. The total phenolic, flavonoid, flavonol, and tannin contents were measured using appropriate methods. The antioxidant potential of extracts was investigated using TAC, DPPH scavenging, and FRAP methods. The α-amylase and α-glucosidase inhibitory activities of extracts were determined using enzymatic methods. The ethyl acetate extracts with the best phenolic content were subjected to HPLC analysis. The extraction yields were higher with methanol. The ethyl acetate extract of P. capitata harvested from P. guajava showed a stable HPLC profile during the development of the plant, while extracts from the plant collected from P. americana and P. mannii showed both qualitative and quantitative variations according to phonological stages of the plant. The inhibition of α-amylase was more pronounced for P. capitata harvested from P. guajava, decreasing during flowering and fruiting, while inhibition of α-glucosidase was not influenced by the phenological stage and the host of the plant. The α-amylase inhibitors were better extracted by ethyl acetate and those of α-glucosidase by ethanol or methanol. The phenolic contents and antioxidant properties of the extracts were influenced by the phenological stage of P. capitata and its hosts. These results suggest that it is preferable to harvest P. capitata during flowering or during fruiting stages on any host. None of the used solvents permitted an optimal extraction of active principles form P. capitata, suggesting that the mixture of solvents must be considered in further studies.

A bacteriological and physicochemical study was conducted in the waters of farms in mountainous regions of Cameroon. The different water samples were collected during two campaigns in December 2018 and February 2019. Ten stations representing the drinking water supply points in our study area were identified. The results showed that these waters contained both pathogenic and commensal fecal bacteria. The highest abundances reached 10x103 CFU/100mL for Salmonella sp., 72x103 CFU/100mL for Staphylococcus aureus, 102x103 CFU/100mL for Brucella suis and 40x103 CFU/100mL for Brucella abortus. These abundances were subject to space-time fluctuations. Water contamination by tweezers was not general and was present only in surface waters (rivers and ponds). The water in the ponds, rivers and wells analyzed were all basic, with low mineralization on average. The dissolved oxygen ranged from 37.5 to 70.6%, nitrate from 3.7 to 19.8 mg/L and iron from 0.01 to 3.5 mg/L. Most of the physicochemical parameters were relatively stable during the two campaigns. The degree of correlation between the physicochemical parameters and the abundance dynamics of the isolated bacteria was heterogeneous. This was clearly more pronounced with Salmonella sp. and Brucella suis. This would be due to the fraction of metabolically active cells present when the bacteria are exposed to unfavorable conditions. Correlations with the abiotic factors were less marked with Staphylococcus aureus and Brucella abortus; this would be due to their tolerance to environmental stresses.

Fusariosis is one of the diseases that cause many pre- and post-harvest losses of tomato fruits. This disease is caused by fungi belonging to the genus Fusarium spp. The present study was carried out to determine the prevalence of Fusariosis in the major tomato fruit production basins in West Cameroon, to inventory and characterize the different Fusarium spp. morphotypes associated with this tomato fruit rot. To achieve this objective, the prevalence of these fruit rots was determined in each production basins. The different morphotypes were obtained from tomato fruit rot. The results showed that the prevalence of this disease was significantly higher and identical in all localities covered by the study according to the Duncan test at P ≤ 0.05. Fruits from these basins contained nine morphotypes of Fusarium spp. of which the most frequent were F1DS morphotypes (16.92%) from Dschang followed by F1BD (16.62%) and F3BD (16.34%) from Mbouda fruits and the least frequent was F3FBT from Foumbot. The study of the morpho-cultural characters of the different morphotypes of Fusarium spp. showed that the morphotypes F2DSC from Dschang, F1FBT, F3FBT from Foumbot, F1BD, F3BD and F4BD from Mbouda showed the greatest radial growth. Similarly, the morphotypes F2DSC from Dschang and F1BD from Mbouda showed the fastest growth rate, while the lowest growth rates were recorded with the F1DSC, F3DSC from Dschang and F2FBT from Foumbot. Foumbot's F3FBT and Mbouda's F1BD morphotypes showed the highest sporulation rate. On the other hand, the F3DSC morphotype of Dschang showed the lowest number of conidia.

The aim of the present work is to study and compare antidiabetic activity of extracts from Catharentus roseus, Persea americana, and Eucalyptus globulus as well as their mechanism of action. The aqueous and methanolic plant extracts were respectively prepared by decoction and maceration. The phytochemical screening was done by standard methods. The extracts were subsequently tested in vivo on Wistar albino rats (Rattus norvegicus) with temporary hyperglycemia. The methanolic extract of P. americana leaves showing the best activity was selected for the antidiabetic test at doses 37.5, 75 and 150 mg/kg. For that purpose, permanent diabetes mellitus was induced in rats fasted overnight by intraperitoneal injection of alloxan (150 mg/kg). Hematological and biochemical parameters were evaluated from the cardiac puncture’s blood. The antidiabetic mechanism of action of the 6 extracts was performed by evaluating their inhibitory activity on alpha glucosidase, beta glucosidase and glucoamylase. Phytochemical analysis of aqueous and methanolic extracts revealed that all extracts contain phenols, anthraquinones and tannins. On the other hand, no extract contains sterols. All extracts showed hypoglycemic activities. The antidiabetic tests showed that the methanolic extract of P. americana caused a decrease in blood sugar level in all the treated rats with the dose of 150 mg / kg of body weight being the most effective, without any adverse side effect in the animals. All the tested extracts showed an inhibitory activity against alpha glucosidase and glucoamylase enzymes and have no inhibitory activity on beta glucosidase. The results of the present study demonstrate the antidiabetic properties of the tested plants through inhibitory effect on alpha glucosidase and glucoamylase enzymes with P. americana being the most active.

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