Antiradical potential and antifungal activities of essential oils of the leaves of Citrus latifolia against Phaeoramularia angolensis

Investigations were conducted to determine the chemical composition, antiradical and antifungal activities of the essential oil extracted from the fresh leaves of Citrus latifolia var. Tahiti from Cameroonagainst Phaeoramularia angolensis. The essential oil obtained by hydrodistillation was analysed by GC and GC/MS. The disc diffusion method was used to evaluate the zone of fungal growth inhibition atvarious concentrations of the oil while the antiradical activity of the oil was studied by the DPPH (diphenyl picryl hydrazyl) method. The chemical analysis revealed 26 components among whichlimonene (45.76%), geranial (13.12%) and neral (10.35%) were the main components. The antiradical activity of C. latifolia essential oil (SC50 = 9.93 g/l) was less than that of butylated hydroxyl toluene (BHT) which was used as the reference compound (SC50 = 7.02 x 10-3 g/l). After 40 days of incubation on oil – supplemented medium, the growth of P. angolensis was totally inhibited by 1600 mg/l of C. latifolia oil. Results obtained in the present study indicate the possibility of exploiting C. latifolia var Tahiti essential oil to combat P. angolensis which is responsible for heavy losses of Citrus fruits harvests

Anti-inflammatory, anthropometric and lipomodulatory effects Dyglomera® (aqueous extract of Dichrostachys glomerata) in obese patients with metabolic syndrome

Background: Increased visceral fat, dyslipidemia and increased markers of inflammation and coagulation are cardiovascular risk factors commonly encountered in obese people with metabolic syndrome. Previous studies have shown that ground Dichrostachys glomerata (DG), a spice used in Western Cameroon, can have beneficial effects on inflammation and various other cardiovascular disease risk factors. The purpose of the present study was to evaluate the effects of Dyglomera®, an aqueous extract of DG (standardized to NLT 10% polyphenols) on certain anthropometric, biochemical (including pro-inflammatory and pro-thrombotic states) and hemodynamic parameters in obese patients with metabolic syndrome. Methods: The study was an 8-week randomized, double-blind, placebo-controlled trial involving 116 males and 202 females aged between 24 and 58 years. Participants were randomly divided into two groups: treatment and placebo. Capsules containing the active treatment (200 mg Dyglomera®) or placebo (200 mg maize powder) were administered 30–60 minutes before lunch and dinner throughout the study period. Various biochemical (namely, blood glucose, lipid profile, pro-inflammatory and pro-thrombotic markers), anthropometric and hemodynamic parameters were measured at baseline and after 4 and 8 weeks of treatment.Results: At the end of the study, the Dyglomera® group showed statistically significant differences in all 16 parameters compared to baseline values. Changes in BMI and waist circumference were accompanied by changes in biochemical parameters, with the exception of adiponectin levels which were not correlated to waist circumference and PAI-1 values. The results confirm the hypothesis that Dyglomera®, the aqueous extract of DG, has anti-inflammatory properties, and is effective in reducing cardiovascular disease risk factors associated with metabolic syndrome in obese human subjects

Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) in Cameroon: case study on its distribution, damage, pesticide use, genetic differentiation and host plants

Open Access JournalMaize farmers in sub-Saharan Africa recently experienced unusual damage in their farms, attributed to the fall armyworm (FAW) Spodoptera frugiperda (J. E. Smith). This pest was first recorded in Africa in 2016, but detailed information on its distribution and damage and farmer's response in invaded areas are largely lacking. In this study, we determined FAW distribution, genetic diversity, host plants, crop damage, and farmers' responses. S. frugiperda was recorded in the 10 regions of Cameroon. Average percentage of infested plants and damage severity (on a scale of 1 to 5) were lowest-20.7 ± 7.4% and 2.1 ± 0.1 respectively-in the Sahelian regions and greatest-69.0 ± 4.3% and 3.1 ± 0.1 respectively-in the Western Highlands. Altitude did not influence FAW incidence and severity and its larvae infrequently co-occurred with maize stemborers on the same plants, suggesting possible direct and/or indirect competition between the two groups of maize pests. In response to this new threat to maize production, farmers have opted for the application of synthetic pesticides. Although our experiments were not designed to determine pesticide efficacy, as parameters such as time since application were not considered, our observations suggest lack of a drastic effect on S. frugiperda infestations on maize. There were two haplotypes of FAW co-occurring in Cameroon corresponding to the rice and corn strains and separated by 1.7% sequence divergence, which does not support the existence of cryptic species. S. frugiperda larvae were also recorded on Sorghum bicolor (L.) Moench (10.6%), Solanum tuberosum L. (2.8%), Ipomoea batatas (L.) Lam. (1.9%), Saccharum officinarum L (0.8%), Phaseolus vulgaris L. (0.4%) and Gossypium hirsutum L. (1.9%). This study show that two strains are present in all agroecological zones in Cameroon, and probably in neighboring countries of central Africa sharing the same agroecologies. Management options should therefore consider the use of specific natural enemies and an informed decision of intervention based on strain capture and damage threshold, to avoid pesticide resistance that may arise from inadequate use of chemicals. Further studies should also be undertaken to assess the response of the two S. frugiperda strains to biopesticides and botanical insecticides

The effects of ProAlgaZyme novel algae infusion on metabolic syndrome and markers of cardiovascular health

<p>Abstract</p> <p>Background</p> <p>Metabolic Syndrome, or Syndrome X, is characterized by a set of metabolic and lipid imbalances that greatly increases the risk of developing diabetes and cardiovascular disease. The syndrome is highly prevalent in the United States and worldwide, and treatments are in high demand. ProAlgaZyme, a novel and proprietary freshwater algae infusion in purified water, has been the subject of several animal studies and has demonstrated low toxicity even with chronic administration at elevated doses. The infusion has been used historically for the treatment of several inflammatory and immune disorders in humans and is considered well-tolerated. Here, the infusion is evaluated for its effects on the cardiovascular risk factors present in metabolic syndrome in a randomized double-blind placebo-controlled study involving 60 overweight and obese persons, ages 25–60. All participants received four daily oral doses (1 fl oz) of ProAlgaZyme (N = 22) or water placebo (N = 30) for a total of 10 weeks, and were encouraged to maintain their normal levels of physical activity. Blood sampling and anthropometric measurements were taken at the beginning of the study period and after 4, 8 and 10 weeks of treatment. Eight participants did not complete the study.</p> <p>Results</p> <p>ProAlgaZyme brought about statistically significant (p < 0.001) reductions in the following: weight, body fat, total cholesterol, LDL-cholesterol, triglycerides, C-reactive protein and fasting blood glucose levels, accompanied by a significant (p < 0.001) increase in HDL-cholesterol levels over the 10-week study period. The infusion was well-tolerated and no side effects were noted.</p> <p>Conclusion</p> <p>ProAlgaZyme (4 fl oz daily) consumption resulted in significant reductions in weight and blood glucose levels, while significantly improving serum lipid profiles and reducing markers of inflammation, thus improving cardiovascular risk factors in overweight and obese subjects over a course of 10 weeks with an absence of adverse side effects.</p> <p>Trial Registration</p> <p>US ClinicalTrials.gov NCT00489333</p

Temperature-dependent phenology of the parasitoid Fopius arisanus on the host Bactrocera dorsalis

Fopius arisanus (Sonan), an egg-pupal parasitoid of numerous fruit fly species, was recently introduced into Africa for the control of the Oriental fruit fly, Bactrocera dorsalis (Hendel). In this study, life-table data of F. arisanus were generated under laboratory conditions at six constant temperatures (15, 20, 25, 30, 28 and 35&nbsp;°C; 75% RH, L12:D12 photoperiod) and under variable conditions in a screenhouse on B. dorsalis. Several non-linear functions were fitted to model species development, mortality, longevity and oviposition using the Insect Life Cycle Modeling (ILCYM) software. The established phenology models were stochastically simulated at variable temperatures to estimate the life table parameters. Fopius arisanus completed development from egg to adult at all the temperatures tested except at 35&nbsp;°C. Mean developmental time from egg to adult was inversely proportional to the temperature. The minimum temperature threshold (Tmin) from egg to adult was 8.15&nbsp;°C, while the maximum temperature threshold (Tmax) was estimated at 34.2&nbsp;°C. The optimal temperature for immature stages survival was predicted for 20-30&nbsp;°C. The optimum fecundity estimated was 251 eggs/female at 22&nbsp;°C. Following the stochastic simulations under natural conditions of the selected agro-ecological zones, it appears that the Humid Forest with Bimodal Rainfall provides a suitable thermal condition for potential population growth of F. arisanus. The present study shows the importance of temperature on the demographic parameters of F. arisanus. Implications of present findings on the biological control of B. dorsalis under climate change scenarios is discussed

How does cultivar, maturation, and pre-treatment affect nutritional, physicochemical, and pasting properties of plantain flours?

Open Access JournalThe effect of cultivar, ripening stage, and pre-treatment method were investigated on the nutritional, physicochemical, and pasting properties of plantain flours from two plantains and two plantain hybrids. There were significant variations (p < 0.05) in chemical composition and physical properties influenced by the interaction of cultivars, ripening stages, and pre-treatment methods. The highest levels of amylose, water-holding capacity (WHC), and oil-holding capacity (OHC) were observed in unripe flours and acid-treated flour recorded the highest content of resistant starch (RS). Flour after pre-blanching contained the highest level of total phenolic (TP), carotenoid contents, and browning index (BI) value. In contrast, acid-treated flours had the lowest BI value. As ripening progressed, peak viscosity and breakdown values increased but final viscosity, setback, and pasting temperature values were reduced. Untreated flour samples showed the highest peak viscosity. Higher breakdown values were found in acid-treated samples and higher setback values in pre-blanched samples

Natural enemies of fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) in different agro-ecologies

Open Access Journal; Published online: 31 May 2021Fall armyworm (FAW) Spodoptera frugiperda (J.E. Smith) and southern armyworm (SAW) Spodoptera eridania (Stoll) have become major threats to crops in Africa since 2016. African governments adopted emergency actions around chemical insecticides, with limited efforts to assess the richness or roles of indigenous natural enemies. Field surveys and laboratory studies were conducted to identify and assess the performance of parasitoids associated with spodopterans in Cameroon. FAW was the most abundant spodopteran pest. Telenomus remus (Nixon), Trichogramma chilonis (Ishi), Charops sp. (Szépligeti), Coccygidium luteum (Cameron), Cotesia icipe (Fernandez & Fiaboe), and Cotesia sesamiae (Cameron) are the first records in the country on spodopterans. Telenomus remus, T. chilonis, C. icipe, and Charops sp. were obtained from both FAW and SAW; C. luteum and C. sesamiae from FAW. The distribution of spodopterans, their endoparasitoids, and parasitism rates varied with host, season and location. In the laboratory, T. remus showed significantly higher parasitism on FAW than SAW, and significant differences in the development parameters between the two host eggs, with shorter development time on FAW. It induced significant non-reproductive mortality on FAW but not on SAW. Developmental parameters showed that C. icipe has a shorter development time compared to other larval parasitoids. Implications for conservative and augmentative biocontrol are discussed

Influence of bunch maturation and chemical precursors on acrylamide formation in starchy banana chips

The present study investigated the effect of ripening stages and chemical precursors on acrylamide formation in deep-fried chips of five plantains and one cooking banana. The highest level of acrylamide was found in the cooking banana, followed by False Horn plantain and French plantain, respectively. French plantain hybrids exhibited a significantly lower (P 0.60) with acrylamide formation in fried chips. The higher level of TP was significantly related (P < 0.05) to the lower level of acrylamide (r = −0.62). The reduced levels of carotenoid isomers, except lutein, during fruit ripening were positively correlated (P < 0.05) with acrylamide formation, especially trans-BC (r = 0.72) and 9-cis-BC(r = 0.64)

Subterranean microbiome affiliations of plantain (Musa spp.) under diverse agroecologies of western and central Africa

Open Access Article; Published online: 29 Sep 2021Plantain (Musa spp.) is a staple food crop and an important source of income for millions of smallholder farmers in sub-Saharan Africa (SSA). However, there is a paucity of knowledge on soil microbial diversity in agroecologies where plantains are grown. Microbial diversity that increases plant performance with multi-trophic interactions involving resiliency to environmental constraints is greatly needed. For this purpose, the bacterial and fungal communities of plantain fields in high rainfall forests (HR) and derived savannas (SV) were studied using Illumina MiSeq for 16S rDNA and ITS amplicon deep sequencing. Microbial richness (α- and β-diversity), operational taxonomic units, and Simpson and Shannon–Wiener indexes (observed species (Sobs), Chao, ACE; P < 0.05) suggested that there were significant differences between HR and SV agroecologies among the most abundant bacterial communities, and some specific dynamic response observed from fungal communities. Proteobacteria formed the predominant bacterial phylum (43.7%) succeeded by Firmicutes (24.7%), and Bacteroidetes (17.6%). Ascomycota, Basidiomycota, and Zygomycota were the three most dominant fungal phyla in both agroecologies. The results also revealed an immense array of beneficial microbes in the roots and rhizosphere of plantain, including Acinetobacter, Bacillus, and Pseudomonas spp. COG and KEGG Orthology database depicted significant variations in the functional attributes of microbes found in the rhizosphere to roots. This result indicates that the different agroecologies and host habitats differentially support the dynamic microbial profile and that helps in altering the structure in the rhizosphere zone for the sake of promoting synergistic host-microbe interactions particularly under resource-poor conditions of SSA