Piper Guineense Research Articles

English

The study compared the antimicrobial activities of essential oils (EOs) from Piper guineense (Uziza) and Xylopica aethiopica (Uda) using diffusion and dilution assays, and evaluated their antioxidant properties at different temperatures. Comparison of the antimicrobial activities was determined using well-in-agar diffusion, disc diffusion and broth dilution methods against Escherichia coli, Salmonella sp and Bacillus cereus as test isolates. The antioxidant activities at different temperatures (28, 50 and 70°C) were determined using 1,1- diphenyl-2-picrylhydrazyl (DPPH), ferric ion reducing antioxidant power (FRAP) and Fe2+ chelation methods. Their antimicrobial activities increased with increase in concentration. From the diffusion assays, B. cereus was more susceptible to the EOs than other isolates (19.5 and 18.0 mm). MIC values obtained from the broth dilution assay (8.0 – 16.0 mg/mL) were generally much lower than those obtained from disc diffusion and well-in-agar diffusion assays. Percent inhibition of isolates using broth dilution method ranged from 91.28 to 96.86%. Their antioxidant activities decreased with increase in temperature. P. guineense EO yielded higher DPPH scavenging activity (43.25, 46.64 and 33.36%, respectively) and Fe2+ chelating ability (25.60, 12.58 and 8.97 mg/g, respectively) at the different temperatures, while FRAP elicited the strongest antioxidant ability of the EOs (70.10, 37.51 and 26.55 mg/g, respectively). The EOs exhibited their strongest antioxidant abilities at 28°C.   Key words: Microbial isolates, antimicrobial susceptibility testing, antioxidant capacity, spices, essential oils.

Potential of Five Local Plant as Protectant against Hide Beetle, Dermestes maculatus Degeer Infesting Dry Cat Fish; Clarias gariepinus Burchell

Efficacy of varying amounts of five selected local plant namely : Balanite aegyptiaca, Eugenia aromatica, Piper guineense, Ocimum gratisimum, and Ziziphus mauratania against the mortality, oviposition, progeny emergence and weight loss of dried fish due to infestation by Dermestes maculatus was studied under ambient conditions. The plant were pulverised into powders and applied as 2.0, 4.0 and 6.0 g per 50 g of dried fish. Three pairs of newly emerged adults by were inoculated into each of the treated fish in a beaker, arranged in a Complete Randomized Design in the laboratory. The result showed all the plant powders tested evoked significant mortalities of adults at the highest concentration (6) after 3 and 7 days of post-treatment when compared with untreated control. The rate of oviposition was drastically suppressed by all plant powders, especially at higher concentration. The number of adults emerged were significantly lower than control at (p>0.05). Similarly, all the plant's powders significantly prevented weight loss at highest concentration after 12 weeks of post-treatment periods. These results have shown that tested plants demonstrated potential ability against adults hide beetle infesting dried fish.

Anti-staphylococcal activity and antibiotic-modulating effect of Olax subscorpioidea, Piper guineense, Scorodophloeus zenkeri, Fagara leprieurii, and Monodora myristica against resistant phenotypes

Anti-staphylococcal activity and antibiotic-modulating effect of Olax subscorpioidea, Piper guineense, Scorodophloeus zenkeri, Fagara leprieurii, and Monodora myristica against resistant phenotypes

Alkaloid-Rich Crude Extracts, Fractions and Piperamide Alkaloids of Piper guineense Possess Promising Antibacterial Effects.

Piper guineense is a food and medicinal plant commonly used to treat infectious diseases in West-African traditional medicine. In a bid to identify new antibacterial compounds due to bacterial resistance to antibiotics, twelve extracts of P. guineense fruits and leaves, obtained by sequential extraction, as well as the piperine and piperlongumine commercial compounds were evaluated for antibacterial activity against human pathogenic bacteria. HPLC-DAD and UHPLC/Q-TOF MS analysis were conducted to characterize and identify the compounds present in the extracts with promising antibacterial activity. The extracts, with the exception of the hot water decoctions and macerations, contained piperamide alkaloids as their main constituents. Piperine, dihydropiperine, piperylin, dihydropiperylin or piperlonguminine, dihydropiperlonguminine, wisanine, dihydrowisanine and derivatives of piperine and piperidine were identified in a hexane extract of the leaf. In addition, some new piperamide alkaloids were identified, such as a piperine and a piperidine alkaloid derivative and two unknown piperamide alkaloids. To the best of our knowledge, there are no piperamides reported in the literature with similar UVλ absorption maxima and masses. A piperamide alkaloid-rich hexane leaf extract recorded the lowest MIC of 19 µg/mL against Sarcina sp. and gave promising growth inhibitory effects against S. aureus and E. aerogenes as well, inhibiting the growth of both bacteria with a MIC of 78 µg/mL. Moreover, this is the first report of the antibacterial activity of P. guineense extracts against Sarcina sp. and E. aerogenes. Marked growth inhibition was also obtained for chloroform extracts of the leaves and fruits against P. aeruginosa with a MIC value of 78 µg/mL. Piperine and piperlongumine were active against E. aerogenes, S. aureus, E. coli, S. enterica, P. mirabilis and B. cereus with MIC values ranging from 39–1250 µg/mL. Notably, the water extracts, which were almost devoid of piperamide alkaloids, were not active against the bacterial strains. Our results demonstrate that P. guineense contains antibacterial alkaloids that could be relevant for the discovery of new natural antibiotics.

Evaluation of five storage technologies to preserve quality composition of maize in Nigerian markets

Maize needs to be stored using good and safe postharvest management measures that will maintain the quality as at harvest. Insects and moisture must be controlled in storage to ensure quality and methods to achieve this, such as the use of reduced-risk measures were evaluated in this study, conducted February–December 2016. The efficacy of Bularafa diatomaceous earth (DE), Piper guineense (Botanical), PICS bags, ZeroFly® bags and permethrin (Rambo™) in preserving maize quality in Nigerian markets was assessed. A sixth treatment comprised maize in untreated polypropylene bags. Study locations were in four markets in Ibadan, Ilorin and Oyo towns. Each market had a storehouse, which contained experimental 100-kg bags. In each storehouse, each technology had six bags, which were all sampled monthly except in PICS treatment where six bags were destructively sampled every four months. Data taken in February) and December) showed that quality of maize in PICS bags was best having the lowest percentage of insect damaged kernels, numerical based (%IDKNB), — 0.01 ± 0.01and 0.02 ± 0.01; %IDKWB— weight based were 0.00 ± 0.00 and 0.00 ± 0.00); % weight loss (0.01 ± 0.01; 0.01 ± 0.01), % number of discolored maize (0.02 ± 0.01; 0.01 ± 0.01) and % seed germination (96.77 ± 0.53; 98.37 ± 0.35) respectively. Treated and untreated maize had mean aflatoxin levels below limit of detection of 5 ppb in February and December (0.47 and 1.66), respectively and their proximate composition were within ranges reported in literature. By December, untreated maize had the highest %IDKNB (1.42 ± 0.22), %IDKWB (1.07 ± 0.18), % weight loss (0.36 ± 0.07) and lowest % seed germination (88.09 ± 0.98) when compared to the evaluated storage technologies Therefore, these five technologies can be incorporated in integrated management of storage insect pests in storehouses.

An ethnobotanical survey and antifungal activity of Piper guineense used for the treatment of fungal infections in West-African traditional medicine

Ethnobotanical relevancePiper guineense occurs commonly in West Africa where it is used for fungal infections instead of the costly and not always accessible conventional antifungals. Fungal, yeast-based diseases are common in West-Africa especially among those living with HIV/AIDS, and thus this study was performed in Imo state, South-Eastern Nigeria, where P. guineense is predominantly used for the treatment of fungal diseases, such as skin rashes, oral thrush and vaginosis. Aim of studyThe scarce number of previous studies on the documentation of the traditional uses of P. guineense extracts for the treatment of fungal infections in Nigeria prompted this survey. The investigation focused on how traditional healers recognize and diagnose fungal infections, how P. guineense is collected, on the various parts used for the treatments, methods of preparations, administrations and treatments. In addition, an in vitro antifungal screening of P. guineense fruit and leaf extracts of various polarities, and piperine and piperlongumine, representing the main constituents in these extracts, were performed. MethodsA house to house ethnobotanical survey was conducted using questionnaires. Twenty traditional medical practitioners (TMP) and herb sellers from ten villages were interviewed. Four human pathogenic strains of yeast and Cryptococcus neoformans, a yeast-like basidiomycete causing meningitis in immunocompromised individuals, were used for the antifungal screening. ResultsThe traditional medical practitioners (TMP) and herb sellers explained that the leaves and fruits are the most commonly used plant parts for the treatments. The oral intake of the extracts in locally produced bamboo alcohol (Kai-kai) is the most common method of administration. In accordance with these recorded traditional uses, we found that extracts of P. guineense were growth inhibitory against the fungal strains with MIC values ranging from 39 to 2500 µg/mL. The lowest MIC value of 39 µg/mL was recorded for a methanol fruit extract against Candida albicans, C. glabrata and C. tropicalis. In addition, ethanol and hexane fruit extracts were effective against the growth of C. albicans and C. glabrata, respectively, with a MIC of 78 µg/mL. Piperlongumine and piperine were active against C. albicans with MIC values of 39 and 78 µg/mL respectively. ConclusionP. guineense fruit and leaf extracts, as well as their piperamide alkaloid constituents piperine and piperlongumine, have interesting antifungal properties and could have potential as new antifungal scaffolds. Our results warrant further in-depth investigations to isolate and characterize piperamide alkaloids and other compounds responsible for the antifungal activity in the extracts.

Proximate, Mineral and Phytochemical Composition of Piper guineense Seeds and Leaves

Proximate, Mineral and Phytochemical Composition of Piper guineense Seeds and Leaves

English

The study was conducted to evaluate the preservative potentials of essential oils (EOs) of Piper guineense, Xylopica aethiopica and Tetrapleura tetraptera in mixed fruit juice and determine their antioxidant capacity. The preservative effect at varying concentrations was evaluated using S. cerevisiae, S. aureus and B. cereus as test isolates. The antioxidant properties were determined using 1,1- diphenyl-2-picrylhydrazyl (DPPH) and ferric ion reducing power assay (FRPA) methods. Concentrations (10 and 5%) of P. guineense and X. aethiopica EOs reduced the number of S. cerevisiae by one log cycle on the 10th day of storage, while 3.3% reduced it by one log cycle after 14 days. The 10% concentration produced a log cycle reduction in the growth of S. aureus and B. cereus on the 12th day. However, 5% concentration reduced the growth of B. cereus by one log cycle on the 14th day. T. tetraptera had the largest amounts of vitamin A (544.41 iu/100 mL), phenol (1.81%) and flavonoids (0.45%). P. guineense had the highest value for vitamin E (37.03 iu/100 mL). X. aethiopica EO produced the highest scavenging activity (46.04%), while P. guineense EO produced the strongest reducing power activity (38.64%). The EOs can act as natural preservative in mixed fruit juice. Their inclusion in such products can improve the products thereby serving as functional foods/beverages, and thus can reduce the risks of cancer formation and chronic diseases in humans. Key words: Mixed fruit juice, preservation, microbial isolates, essential oils, antioxidant ability.

Evaluation of the Anti-inflammatory Activity of Piper guineense Schumach. & Thonn. Seeds Fractions using In vitro and In vivo Models

Piper guineense Schumach. & Thonn. seeds are employed in ethnomedicine practice as therapy against inflammatory disorders. This study was designed to determine the most active anti-inflammatory fraction of P. guineense seed using in vitro and in vivo models. Pulverized P. guineense seeds were partitioned into hexane and aqueous fractions using solvent-solvent partitioning method. Heat-induced protein denaturation, hypotonicity-induced hemolysis of erythrocyte membrane, anti-proteinase assays and formaldehyde-induced inflammation rat model were carried out. Results showed that hexane fraction of P. guineense seeds (HFPGS) significantly (P<0.01) inhibited heat-induced protein denaturation and proteinase activity while it stabilized (P<0.05) erythrocyte membrane against hypotonicity-induced hemolysis when compared with aqueous fraction of P. guineense seeds (AFPGS). Furthermore, 100 mg/kg body weight (b.w.) HFPGS significantly (P<0.01) suppressed 2% v/v formaldehyde-induced paw thickness in rats by 83.30 ± 0.03% on the 7th day when compared with rats treated with 100 mg/kg b.w. AFPGS (34.08 ± 0.02%) and 10 mg/kg b.w. Diclofenac sodium (66.15 ± 0.05%). In addition, experimental rats treated with HFPGS had significantly (P<0.05) reduced alanine and aspartate aminotransferase activities and modulated hematological cells when compared with AFPGS rats. Thus, hexane fraction of P. guineense seeds showed substantial anti-inflammatory activity and could serve as a viable source for anti-inflammatory agent(s).

Nutritional composition and microbial load of &lt;i&gt;Eugenia caryophyllus&lt;/i&gt; and &lt;i&gt;Piper guineense&lt;/i&gt; spices

This study determined the proximate composition, mineral content and microbial load of Eugenia caryophyllus (EC) and Piper guineense (PG) obtained from Garki (gk), Wuse (ws) and Karmo (km) markets of FCT, Abuja in order to ascertain the nutritional value and their safety from being contaminated with heavy metals or microbes. The results obtained for proximate (moisture ash, fibre, protein, lipid and carbohydrates) analysis, mineral content and microbial load were within the following ranges 6.14-9.07% and 6.00-7.00% (moisture), 5.79-8.04% and 5.28-7.64% (ash), 5.44-8.62% and 6.32-8.28% (fibre),1.02-1.93% and 1.37-2.54% (protein), 2.33-7.78% and 5.33-7.34% (lipid),67.53-73.84% and 69.20-75.02% (carbohydrates); 0.1-6.5μg/g and 3.05-5.85μ g/g (Energy value); 2.006-2.6672kcal/100g (Cr), 0- 868.4 μg/g and 244-326.4μg/g (Fe), 43.45-46.75 μg/g and 9.65-81.45μg/g (Mn), 57.45-115.35 μg/g and 54- 96.9 μg/g (Mg), 233.05-261μg/g and 216.15-234.65μg/g (K), 0.25-6.80μg/g and 15.65-20.10μg/g (Zn) and 12.15- 62.90μg/g and 19.4-29.90μg/g (Pb). ANOVA results of the parameters analyzed range from significant difference (˂0.0001) to no significance difference (0.1862) among the samples. The microbial load indicated total viable count range of 1.41×10 2 cfu - 2.04×10 2 cfu for Piper guineense and 0.19×10 2 cfu - 0.69 x 10 2 cfu for Eugenia caryophyllus , while yeast/mould, coliform and pathogenic organisms were not detected. Both spices have low level of most of the proximate values with the exception of carbohydrate; but they are rich in minerals. All the samples contained lead above WHO limits (10μg/g) established for herbal medicines. Keywords: Spices; Nutritional value; Mineral content; Microbial load

Efficacy of Piper guineense Schumach. seed powder in the control of Callosobruchus maculatus (Fabricius, 1775) (Coleoptera: Chrysomelidae: Bruchinae) and on the nutritional and organoleptic characteristics of stored cowpea Vigna unguiculata (L.) Walp.

Abstract Brown pepper (Piper guineense) seed powder, used for culinary and medicinal purposes, was evaluated in the laboratory with a conventional storage chemical, actellic 2% dust (Pirimiphos-methyl), as standard, to protect stored cowpea against the cowpea bruchid, Callosobruchus maculatus. Four rates of the seed powder were used (2.5, 5.0 and 10.0 g/100 g seed with a control, 0.0 g) while actellic dust was applied at 1.0, 2.0, 3.0 g/100 g seed and 0.0 g/100 g seed as control. Data on percentage mortality, oviposition, adult emergence and seed damage were collected over a six-month period. Weevil perforation indexes (WPI) were estimated with the seed damage data. All data were analysed for variance at P≤0.05. Actellic dust at the lowest dose inflicted adult mortality (90 – 100%) in the first 48 h after treatment and prevented oviposition (95 – 100%) in the first five months of storage compared to the control. The highest rate of Piper guineense application caused mortality of up to 90.0% in 48 h, reduced oviposition (70 – 80%), decreased adult emergence (15.90 to 28.40 insects) as against the control (104.7 – 272.7 insects) and reduced seed damage by 80 % with a WPI of between 33.3 and 10.0 %. Proximate analysis and germination tests indicated that the treatment materials increased the moisture and crude fibre content, decreased crude protein content but had no significant effect on the viability of stored seeds. Organoleptic tests demonstrated that treatment materials had no significant negative effect on taste, odour, texture, appearance and overall acceptability of cooked cowpea seeds after six months of storage. It can be safely concluded that the powdered form of P. guineense seed at the highest doses (5.0 and 10.0 g) gave significant protection of cowpea seeds against the cowpea bruchid, which compared favourably with actellic dust when applied topically.

Comparative hypoglycemic potentials and phytochemical profiles of 12 common leafy culinary vegetables consumed in Nsukka, Southeastern Nigeria.

Background Metabolic disease like diabetes mellitus is on the increase in developing countries due to lack of access to orthodox medicine owing to its high cost. Health benefits of culinary vegetables cannot be overemphasized. This study therefore aims to profile the hypoglycaemic potentials of 12 common leafy vegetables consumed in Nsukka, Southeastern Nigeria and advise diabetic patients accordingly. Methods A total of 75 albino Wistar rats assigned to 15 groups of five rats per group were used for the study. Diabetes was induced in groups 1-14 rats by intraperitoneal injection of alloxan monohydrate (160 mg/kg), and rats in group 15 were not made diabetic. Groups 1-12 rats were treated with aqueous extracts of the vegetables (200 mg/kg), and group 13 rats received glibenclamide at 2 mg/kg and served as standard control. Rats in groups 14 and 15 received distilled water (10 mL/kg) to serve as negative and normal controls, respectively. The fasting blood glucose (FBG) values of the rats were determined 3, 6 and 24 h post-treatment. Phytochemical studies on the vegetables were also carried out. Results Results revealed that the hypoglycaemic activities of Gongronema latifolium, Pterocarpus santalinoides, Ocimum gratissimum, Pterocarpus mildbraedii and Vernonia amygdalina were comparable (p>0.05) to that obtained for glibenclamide (standard anti-diabetic drug) while Gnetum africanum and Piper guineense did not show significant hypoglycaemic activities. Phytochemicals such as flavonoids, alkaloids, tannins, saponins, glycosides, and terpenes were present in the vegetables. Conclusions It was concluded that the vegetables possess hypoglycaemic activities at different capacities with G. latifolium being the most potent.

Effects of aqueous extracts of Gongronema latifolium leaves and Piper guineense seeds on liver and kidney biomarkers of albino rats

Effects of aqueous extracts of Gongronema latifolium leaves and Piper guineense seeds on liver and kidney biomarkers of albino rats

Etude Phytochimique Et De Cytotoxicité De Quelques Plantes Utilisées Dans Le Traitement De La Stérilité Féminine Au Sud-Bénin

The most cited plant drugs during an ethnobotanical survey conducted for traditional healers and resource persons in southern Benin, used in the treatment of female infertility, were the subject of a phytochemical screening. It aims to determine the chemical substances that are conferred on the plants. These chemical substances are the pharmacological properties that are used for the treat of ailment recognized as being the origin of this disease. As a result, we studied the cytotoxicity of each herbal drug. In total, the organs of 17 plant species involved in this study are Aframomum melegueta, Allium cepa, Anchomanes deformants, Baphia nitida, Carissa spinarum, Elaeis guineensis, Garcinia cola, Kigelia africana, Monodora myristica, Morinda lucida, Musa sapientum, Olax subscorpioidea, Piper guineense, Pterocarpus erinaceus, Pupalia lappacea, Tetrapleura tetraptera, Xylopia aethiopica. The results obtained indicate that the richness in phytochemical element is a function of the species. Thus, Aframomum melegueta, Garcinia kola, Monodora myristica, Tetrapleura tetraptera, Xylopia aethiopica, and Anchomanes difformis are rich in catechin and/or gallic tannins, mucilages, reducing compounds, anthocyanins and/or leucoanthocyanins. On the other hand, no drugs is at same time rich in free anthracenics, steroids and / or terpernoids, alkaloids, saponosides, and quinone derivatives. The calculated CL50 values for each of the plant organs are all greater than 0.1 mg / ml. None of them is toxic. However, the non-toxicity of an herbal drug does not mean the same with the multispecies recipe in which it is used. Pharmacological tests of the various recipes used are also of significant importance.

Enquête Ethnobotanique Sur La Prise En Charge Traditionnelle De L’infertilité Féminine Dans La Région Sanitaire Des Savanes Au Togo

Introduction: The management of female infertility by the conventional medicine is very expensive and its coast is unavailable for the very poor populations. In Africa, an important recourses of medicinal plants are available for health care. Objective: The present study was led to recorder traditional remedies use to treat female infertility in the Sanitary Savannas Region of Togo. Methodology: For data collection, semi interview was used. Data were processed and analysed using ethnobotanical quantitative index. The Selection by Progressive Elimination (SPE) was essentially used for the choice of species. Results: With 51 practitioners interviewed, 79 recipes constituted by 87 species belonging to 48 botanical families were collected. Combretaceae (12,64 %) and Rubiaceae (5,7 %) were the most frequent families. Trees (36,78 %) and shrubs (27,58%) were the main ports. Roots (29,17 %) and leaves (27,5 %) were the most used parts. Recipes were prepared frequently by decoction (51,88 %) and powder (38,12%), and were principally taken orally (47,28 %) and by body bath (43,48 %). Sexually transmitted infections (STI) (143 citations) and Painful menstruations (PM) (108 citations) were the most frequent pathologies. The highest Informants consensus factors were 0,61 and 0,56 respectively for STI and PM. The most important Fidelity degrees was 25,49 % for STI related to Capsicum frutescens and Piper guineense. Related to Aframomum melegueta, Piper guineense and Zanthoxylum zanthoxyloides the Fidelity degree was 19,61% for PM and STI. Blighia sapida, Ganoderma colossus, Kigelia africana and Mangifera indica were selected. Conclusion: Plants with highest fidelity degree and those selected by SPE will be subjected to laboratory tests.

Cytotoxicity and antibacterial activity of fruits extracts of &lt;i&gt;Xylopia aethiopica&lt;/i&gt; against some selected beta-lactamase producing bacteria

Xylopia aethiopica commonly known as the West African pepper tree is consumed as food condiment and also used traditionally in the treatment of cough, bronchitis, dysentery and female sterility. Air-dried and ground fruits of Xylopia aethiopica were extracted using ethanol and the recovered extract was partitioned to give chloroform, water, methanol and n-hexane fractions. The five extracts were screened for antibacterial activity against strains of β-lactamase producing bacteria: Escherichia coli , Proteus sp., and Klebsiella pneumonia as well as cytotoxicity against brine shrimp larvae. The result of the antibacterial screening showed that all the extracts exhibited selective activity against Proteus sp., the interface-2 demonstrated the highest activity with diameter of zone of inhibition of 14mm at 1000μg/disc. On the other hand, methanolic extract showed high cytotoxic activity in the brine shrimp lethality bioassay with LC 50 value of 3.4μg/mland moderate antibacterial activity with diameter of zone of inhibition of 12mm at 1000μg/ml. Keywords: Xylopiaaethiopica ; Extracts; antibacterial activity; β-lactamase producing bacteria; cytotoxicity; brine shrimp lethality bioassay

Comparative Effects of Piper guineense Emulsion and Cabbage-Tomato Intercropping for Controlling Cabbage Pests and Improving Performance

Comparative Effects of Piper guineense Emulsion and Cabbage-Tomato Intercropping for Controlling Cabbage Pests and Improving Performance

In vitro acid-base buffering capacity of some Nigerian green leafy vegetables and fruit juices

Background: Nigerian diets are mostly composed of starchy staples which is usually eaten with vegetable soup or stew. The preponderance of a food type may modify the body buffering capacity and interfere with the development of diseases. Objective: This study was carried out to evaluate the in vitro buffering capacity of some Nigerian green leafy vegetables (GLV) and fruits. Methods: Ten distinct types of green leafy vegetables (GLV) namely: bitterleaf, curry leaf, ewedu leaf, Amaranthus hybridus (locally called green) pumpkin leaf, scent leaf, soko leaf utazi leaf, uziza leaf, water leaf, were oven dried. While fruits like apple, carrot, garden egg, lemon, lime, mango, orange, pineapple, soursop, water melon, were juiced. The dried GLV were homogenised in deionised water and filtered to obtain an extract. The pH of the extract and fruit juices were determined. The in vitro buffering capacities were determined by titrating the extract with initial pH greater than 4 with 1M HCl until pH decreased to 2. Extract with pH lower than 4 was titrated with 1M NaOH until the pH increased to 4. Results: GLV had a high buffering capacity (BC) from (2.03 ± 0.10 to 6.45 ± 0.19). Green (Amaranthus hybridus) had the highest BC while uziza leaf (Piper guineense) had the lowest. The fruits had BC from minus 7.52 ±0.07 to 4.56 ±1.76). Oranges (Citrus sinensis) and pineapples (Annas comosus) had the highest BC. Lemon had the lowest BC of -7.52. other fruits with negative BC were lime; (-5.95 ±2.62) and soursop (-4.57 ± 1.75). Conclusion: Oranges, pineapples, green and water leaf had high buffering capacities. Lemon, lime and soursop had negative buffering capacities. These fruits and GLV can be used as adjuvant for nutrition interventions with the aim of alkalinizing diets for therapeutic purpose against disease and cancer progression.Keywords: Buffering capacity, pH, fruits, vegetables

Optimization of Thin-layer Chromatography and High-Performance Liquid Chromatographic Method for Piper guineense Extracts

In this study, a thin-layer chromatography (TLC) and a high performance liquid chromatographic (HPLC) methods were developed for the chemical profiling, qualitative and quantitative analysis of P. guineense extracts. To obtain a chromatogram with satisfactory resolution and favorable retention time, DryLab software was used to simulate and optimize a HPLC method for the analysis of P. guineense extracts. The aim was to achieve the best possible overall resolution while keeping the analysis time and solvent consumption to a minimum. With the optimized method, a total of 16 main components in the extract were separated with favorable resolution. Optimal TLC conditions were also developed using solvents of various solvent strength (ST) and solvent selectivity (PS) values. The mobile phase composition was systematically tested using various proportions of solvents differing in ST and PS values under the same experimental conditions. During the optimization, emphasis was set on achieving the best possible overall separation of the main components of the extracts (for example piperine). In addition, the effects of the developing chamber was tested using three types of unsaturated chamber conditions: horizontal chamber in sandwich configuration, horizontal chamber in non-sandwich configuration and twin-trough vertical chamber. During the study, a TLC method was developed, and the best mobile-phase composition giving favorable resolution of the bands was toluene: ethyl acetate (PS 6-4 corresponding to 60:40 % v/v). The developing chamber conditions did not affect the TLC separation efficacy in the analysis of P. guineense extracts. The HPLC method was applied to determine the percentage content of piperine in P. guineense. The piperine content was 0.43 % w/w, linearity (0.997), interday precision (% relative standard deviation (RSD), 1.6), intraday precision (% RSD, 2.7 – 5.9), recovery (98.4%), limit of detection (0.001 μg /mL) and limit of quantification (0.003 μg /mL).

Synergistic effect of spinosad with selected botanical powders as biorational insecticides against adults of Tribolium castaneum Herbst, 1797 (Coleoptera: Tenebrionidae)

The synergistic effect of spinosad with three botanical (Aframomum melegueta, Eugenia aromatica and Piper guineense) powders as biorational insecticides against Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) infesting melon (Citrullus lanatus) seeds was investigated. Treatments included sole application of each botanical powder (50 g/kg of melon seed), sole application of spinosad (SASp) (1.0g/kg), mixture of spinosad (0.5 g/kg) + botanical powders (25 g/kg) and an untreated control. Data were collected on tenebronid mortality rate (%) (PM) and melon seed weight loss rate in % (PWL). Phytochemical analysis of the botanicals was also carried out. At 3-14 days after treatment (DAT), PM observed in melon seeds treated with SASp (90.00-100.00%) was not significantly (p&gt;0.05) different from PM observed in melon seeds treated with spinosad + E. aromatica powder (86.67-100.00%) and spinosad + P. guineense powder (85.00-100.00%). PWL observed in melon seeds treated with spinosad + botanical powders (1.17-1.40%) was not significantly different from PWL observed in seeds treated with SASp (0.42%), but it was significantly lower than PWL (3.28%) observed in melon seeds treated with sole application of A. melegueta powder. P. guineense powder had the highest contents of alkaloids (868.33 mg/100 g), tannins (550.00 mg/100 g), phenolics (53.57 GAE/g), and steroids (740.00 mg/100 g). E. aromatica powder had the highest contents of flavonoids (1466.67 mg/100 g), terpenoids (1276.00 mg/100 g) and cardiac glycosides (7.33 mg/100 g), while A. melegueta powder had the highest content of saponins (376.67 mg/100 g). The combination of spinosad with P. guineense powder or E. aromatica powder performed better than the combination with A. melegueta powder and is therefore recommended as a biorational approach for the control of T. castaneum.