Integrated Soil Fertility Management Options for Maize Production and Sustainability in the Western Highlands of Cameroon

Background: Continuous cultivation without fertilizer application and soil erosion are responsible for plant nutrient depletion and yield decline of major food crops in Sub-Saharan Africa.Methods: Nutrient status of Calliandra calothyrsus, Leucaena leucocephala, Acacia angustissima and Cassia spectabilis were characterized. Field experiments were conducted over two years in the Western Highlands of Cameroon to evaluate the effects of the application of leaf biomass of agroforestry tree species and mineral fertilizers on maize yield performance. The residual effects on soil physicochemical properties were also investigated for umbric Cambisols of Babungo and ustic Oxisols of Bansoa. Ten treatments encompassing; sole leaf biomass of Calliandra calothyrsus, Leucaena leucocephala, Acacia angustissima and Cassia spectabilis, leaf biomasses combined with NPK fertilizer, sole NPK fertilizer and absolute control were laid in a randomized complete block design and replicated three times. Data were subjected to analysis of variance and the Duncan Test (p < 0.05) used for mean separation.Results: All the species characterized had nitrogen, polyphenol and lignin contents greater than 2.5 %, 5 % and 15 % respectively. Significant differences (p < 0.05) were observed among treatments on maize growth, productivity parameters and soil chemical properties for both soil types. The highest maize grain yields were recorded in plots amended with 1 t/ha of biomass of Calliandra calothyrsus or Leucaena leucocephala as well as1.5 t/ha of biomass of Acacia angustissima and Cassia spectabilis plus mineral fertilizer (50 N+ 37.5 P2O5 + 45 K2O) on both soils compared to other treatments.on umbric Cambisols and ustic Oxisols respectively. The residual effects of treatments on soil chemical properties showed severe nutrient depletion in control plots and those amended with sole inorganic fertilizer.Conclusions: Combined application of agroforestry tree biomass and inorganic fertilizers remains an appropriate technology to enhance maize yield and sustain production of resource-limited farmers of acid tropical soils..

Antiplasmodial activity of Ethanolic extract of Cassia spectabilis DC leaf and its inhibition effect in Heme detoxification

Background In previous studies, Cassia spectabilis DC leaf has shown a good antiplasmodial activity. Therefore, this study is a follow-up study of the extract of leaf of C. spectabilis DC on its in vitro and in vivo antiplasmodial activity and mechanism as an antimalarial. Methods The extract was fractionated, sub-fractionated and isolated to obtain the purified compound. In vitro antiplasmodial activity test against Plasmodium falciparum to find out the active compound. In vivo test against P. berghei ANKA-infected mice was conducted to determine prophylactic activity and antiplasmodial activity either alone or in combination with artesunate. The inhibition of heme detoxification test as one of the antimalarial mechanisms was carried out using the Basilico method. Results The results showed that active antimalarial compound isolated from C. spectabilis DC leaf had a structural pattern that was identical to (−)-7-hydroxycassine. Prophylactic test of 90% ethanolic extract of C. spectabilis DC leaf alone against P. berghei ANKA-infected mice obtained the highest percentage inhibition was 68.61%, while positive control (doxycycline 13 mg/kg) was 73.54%. In combination with artesunate, 150 mg/kg three times a day of C. spectabilis DC (D0-D2) + artesunate (D2) was better than the standard combination of amodiaquine + artesunate where the inhibition percentages were 99.18 and 92.88%, respectively. The IC50 of the extract for the inhibitory activity of heme detoxification was 0.375 mg/ml which was better than chloroquine diphosphate (0.682 mg/ml). Conclusion C. spectabilis DC leaf possessed potent antiplasmodial activity and may offer a potential agent for effective and affordable antimalarial phytomedicine.

Antimalaria Activity of Cassia spectabilis DC Leaf and Its Inhibition Effect in Heme Detoxification

Background In previous studies, Cassia spectabilis DC leaf has shown a good antimalarial activity. Therefore, this study is a follow-up study of leaf activity and mechanism of C. spectabilis DC as an antimalarial. Methods In vitro antimalarial activity testing using P. falciparum which was done with bioassay guide isolation in order to obtain the active compound. In vivo testing towards infected P. berghei mice was conducted to determine the effects of antimalarial prophylaxis and antimalarial activity in combination with artesunate. Whereas, heme detoxification inhibition testing as one of the antimalarial mechanisms was carried out using the Basilico method. Results The results showed that active antimalarial isolate obtained from C. spectabilis DC leaf had a structural pattern that was identical to (-)-7-hydroxyspectaline. Prophylactic test on infected P. berghei mice obtained the highest dose of inhibition percentage of 90% ethanol extract of C. spectabilis DC leaf was 68.61% while positive (doxycycline) control at 100 mg kg-1 was 73.54%. In antimalarial testing in combination with artesunate, it was found that administering 150 mg kg-1 (three times a day) of C. spectabilis DC (D0 − D2) + artesunate (D2) was better than the standard combination of amodiaquine + artesunate with 99.18% and 92.88% inhibition percentage. For the inhibitory activity of heme detoxification from ethanol extract 90%, C. spectabilis DC leaf had IC50 value of 0.375 mg mL-1 which was better than chloroquine diphosphate. Conclusion These results showed that C. spectabilis DC leaves possesses potent antimalarial activity and may offer a potential agent for effective and affordable antimalarial phytomedicine.

Aktivitas Penghambatan Ekstrak Etanol Daun Cassia Spectabilis Terhadap Pertumbuhan Plasmodium falciparum dan Plasmodium berghei

Background: Antimalarial screening against nine species of the genus Cassia showed that the methanol extract of leaves Cassia spectabilis have the highest activity. Since it will be used as a traditional medicine, hence it is needed further studies of antimalarial activity of these plants by choosing a safer solvent, namely ethanol. Objective: In vitro anti-malarial activity against Plasmodium falciparum was conducted using the method of Trager and Jensen. Methods: The serial solution tested were: 100, 10, 1, 0.1 and 0.01 µg/ mL, while the in vivo test was performed based on Peter’s test (The days suppressive test) that using P. berghei (strain ANKA) infected mice. Results: The results showed that ethanolic extract of C. spectabilis leaves has inhibitory activity against P. falciparum with IC50 value of 12.52 µg/ mL and against P. berghei with ED50 value of 131.5 mg/kg body weight. Conclusions: A further study to see the potential of ethanol extract from C. Spectabilis leaves as anti-malaria is warranted.

Aktivitas Penghambatan Ekstrak Etanol Daun Cassia Spectabilis Terhadap Pertumbuhan Plasmodium falciparum dan Plasmodium berghei

Background: Antimalarial screening against nine species of the genus Cassia showed that the methanol extract of leaves Cassia spectabilis have the highest activity. Since it will be used as a traditional medicine, hence it is needed further studies of antimalarial activity of these plants by choosing a safer solvent, namely ethanol. Objective: In vitro anti-malarial activity against Plasmodium falciparum was conducted using the method of Trager and Jensen. Methods: The serial solution tested were: 100, 10, 1, 0.1 and 0.01 µg/ mL, while the in vivo test was performed based on Peter’s test (The days suppressive test) that using P. berghei (strain ANKA) infected mice. Results: The results showed that ethanolic extract of C. spectabilis leaves has inhibitory activity against P. falciparum with IC50 value of 12.52 µg/ mL and against P. berghei with ED50 value of 131.5 mg/kg body weight. Conclusions: A further study to see the potential of ethanol extract from C. Spectabilis leaves as anti-malaria is warranted.