Characterization of Immunogenic Soluble Crude Proteins from Biomphalaria Pfeifferi Against Schistosoma mansoni

Schistosomiasis is the second most prevalent tropical disease in the world after malaria. Chemotherapy and molluscicides which are the main methods of control do not give lasting protection as the disease continues to spread to other new regions. Previous studies have demonstrated the immunogenic properties of the digestive gland (DG), foot parts (FT) and the rest of body tissue (RT) soluble protein of Biomphalaria pfeifferi against Schistosoma parasite and therefore possible candidates for vaccine development against the parasite. However, information about the chemical composition of the soluble proteins is scanty. The objective of this study was to characterize and determine chemical composition of the DG and FT soluble proteins from Biomphalaria pfeifferi. A total of twelve compounds were identified using GC-MS. N-tert-butyl methylamine and penicillamine were present in both DG and FT soluble proteins. Butylamine S, valine, amino heptanoic acid, 1,1-dimethylamino-1 butane and valienamine were present in the DG soluble protein but were missing in the FT extracts. Tert-butylamine, heptylamine, cycloheptane methylamine, erythro-O-methylthreonine and leucine were present in the FT soluble protein but missing in the DG extracts. FTIR analysis showed N-H stretch at 3100 cm-1, C=O stretch at 1700cm-1, N-H bending at 1600cm-1 and O-H peak at 3500 cm-1 while UV absorption occurred at 240-300 nm thus confirmed the presence of amino acids in the soluble protein extracts. Results from this study justifies medicinal activity of Biomphalaria pfeifferi soluble crude protein extracts. Further studies involving isolation of individual constituents in the crude soluble proteins and subjecting them to bioassay is highly recommended. Keywords: Schistosomiasis; Biomphalaria pfeifferi; Protein extracts; Chemical compounds DOI: 10.7176/JNSR/10-12-03 Publication date:June 30th 202

Characterization of Immunogenic Soluble Crude Proteins from Biomphalaria Pfeifferi Against Schistosoma mansoni

Schistosomiasis is the second most prevalent tropical disease in the world after malaria. Chemotherapy and molluscicides which are the main methods of control do not give lasting protection as the disease continues to spread to other new regions. Previous studies have demonstrated the immunogenic properties of the digestive gland (DG), foot parts (FT) and the rest of body tissue (RT) soluble protein of Biomphalaria pfeifferi against Schistosoma parasite and therefore possible candidates for vaccine development against the parasite. However, information about the chemical composition of the soluble proteins is scanty. The objective of this study was to characterize and determine chemical composition of the DG and FT soluble proteins from Biomphalaria pfeifferi. A total of twelve compounds were identified using GC-MS. N-tert-butyl methylamine and penicillamine were present in both DG and FT soluble proteins. Butylamine S, valine, amino heptanoic acid, 1,1-dimethylamino-1 butane and valienamine were present in the DG soluble protein but were missing in the FT extracts. Tert-butylamine, heptylamine, cycloheptane methylamine, erythro-O-methylthreonine and leucine were present in the FT soluble protein but missing in the DG extracts. FTIR analysis showed N-H stretch at 3100 cm-1, C=O stretch at 1700cm-1, N-H bending at 1600cm-1 and O-H peak at 3500 cm-1 while UV absorption occurred at 240-300 nm thus confirmed the presence of amino acids in the soluble protein extracts. Results from this study justifies medicinal activity of Biomphalaria pfeifferi soluble crude protein extracts. Further studies involving isolation of individual constituents in the crude soluble proteins and subjecting them to bioassay is highly recommended. Keywords: Schistosomiasis; Biomphalaria pfeifferi; Protein extracts; Chemical compounds DOI: 10.7176/JNSR/10-12-03 Publication date:June 30th 202

Analgesic Activity of Conyza Floribunda Extracts in Swiss Albino Mice

Traditional medicine still plays an important role in managing infections especially in Africa. Extracts of Conyza floribunda Kunth are used to treat sore throat, ringworm and other skin related infections, toothache and to stop bleeding from injuries. Extracts from the plant have been reported to exhibit antibacterial and antifungal activities. Previous phytochemical studies on the plant yielded terpenoid, sterols and flavonoids. The aim of the present study was to determine the analgesic activity Conyza floribunda extracts. Methanol, DCM and n-hexane extracts of the plant were subjects to toxicity, hot plate latency and acetic acid induced-writhing tests using Swiss Albino Mice. The plant extract showed analgesic activity in both hot plate latency and acetic acid induced-writhing tests. The extracts significantly increased the response time in the animals compared to the negative control. In the hot plate latency test, the analgesic activity of the extracts and that of morphine rose over time to peak at 90 minutes and then decreased afterwards. In the acetic acid-induces writhing test, administration of the plant extracts significantly reduced the number of abdominal contractions compared to the negative control. The percentage inhibitions of abdominal contractions were 67.2, 46.5 and 39.4 for methanol, DCM and n-hexane extracts respectively. The findings from this study have confirmed the folkloric information that extracts from C. floribunda have analgesic properties. We therefore recommend the extracts from the plant for use in pain management. Further studies should be carried out to isolate and characterize the analgesic principles from the plant. Keywords: Conyza floribunda, Toxicity test, Analgesic activity, Hot plate test, Writhing test DOI: 10.7176/JNSR/12-12-01 Publication date:June 30th 2021

Effect of Acid Treatment on the Chemical Properties of Clays from Selected Sites in Murang’a and Nyeri counties, Kenya

Assessing improvement on the quality of clay has been conducted by treatment with different concentrations of hydrochloric and oxalic acid. This project intended to assess the effect of acid treatment on the elemental composition of clays from selected sites. The clays were leached using hydrochloric and oxalic acid separately at a concentration of 0.0, 0.1, 0.25, 0.5, 1, and 2M. The elemental composition of raw and acid-treated clays was determined using AAS. Elemental composition of the acid-treated clays, in oxide form were in the ranges of 40.80-65.16 % SiO2, 7.16 -30.33 % Al2O3, 0.33-7.62 %TiO2, 0.24-2.65 % K2O, 0.01-1.82 % MgO. The findings of this study showed that the quality of clays could be improved by acid treatment hence the clays can be used as a source of raw materials for industrial applications. Keywords: Acid-treatment, Elemental, raw materials DOI: 10.7176/JNSR/11-22-05 Publication date: November 30th 202

Evaluation of Warburgia ugandensis Extracts and Compounds for Crop Protection against Prostephanus truncates

Insect pests cause a significant loss of maize production in Africa. Maize weevil (Sitophilus zeamais Motchulsky) and the larger grain borer (Prostephanus truncatus Horn) are the most destructive insect pests of maize. Chemical control is the most commonly used and the most effective method at the farm level. However, some of the chemicals cause adverse effects to environment and humans. In addition, insecticides available in the market are expensive and mostly out of reach to smallholder farmers. The use of botanicals for pests and disease control is preferred because plant materials are non-toxic and are readily available. This study investigated the efficacy of extracts and compounds from Warbugia ugandensis leaves for control of P. truncatus infestation in stored maize. All the crude extracts exhibited repellent, toxicity and growth inhibition activities against P. truncates. The most active compounds were polygodial, warburganal, ugandensolide and mukaadial. The findings from this study show that extracts from W. ugandensis are effective in controlling the larger grain borer and therefore could be used to control the pest

Warburgia Ugandensis: A Review of Compounds and Bioactivity

Warburgia species (Canellaceae) are traditionally used to treat a wide range of illnesses including stomach ache, diarrhea, abdominal pains, toothache, oral thrush, venereal diseases, cold and cough, fever, muscle pains, weak joints, skin diseases, malaria, parasitic infections and snake bite. Therapeutic properties of medicinal plants have been linked to the secondary metabolites which are biosynthesized by the plants. The aim of this study was to review the bioactivities and chemical composition of Warburgia ugandensis. The findings from this study show that extracts from the plant have antifungal, antibacterial, antiulcer, insect antifeedant, molluscicidal, antimycobacterial, antileishmanial and anti-plasmoidal effects. The most investigated part of W. ugandensis is the stem bark (22 articles) followed by leaves (15), root bark (6), seeds (2) and fruits (2). All parts the plant have important bioactivities. Sixty nine compounds have been reported from the plant including sesquiterpenes (43), flavonoids (15), lignanamides, and macrocyclic glycosides (10) and fatty acid (1) some of which have demonstrated different bioactivities. The drimane sesquiterpenes are the main class of sesquiterpenes in the plant. The Further investigation of the not well studied parts of the plant such as the flowers and fruits is recommended to determine their chemical composition and efficacy in disease management

A Review of Insecticidal Plant Extractsand Compoundsfor Stored Maize Protection

Insect pests cause significant losses to maize grains both in the fieldsand in storage. Maize weevil (Sitophilus zeamais) and larger grain borer (Prostephanus truncatus) are among the most destructive pests of maize in Africa. Currently, researchers have focused on identification of insecticidal plant extracts and compound through in-vivo and in-vitro experiments, as an alternative to synthetic chemicals which have been reported to have adverse effect on the environment.The aim of this study was to collate and review the fragmented information on plants extracts and compounds with insecticital activity against S. zeamais and P. truncatus and present recommendations for future research. Peer-reviewed articles were retrieved from Scopus, Science Direct, SciFinder and Google Scholar. This study led to identification of 123 plant species which have been examined for insecticidal activity focusing more on S. zeamais rather than P. truncatus.It is also evident that most studies end with the crude plant extracts. Effort towards identification of insecticidal principles from the plants is negligible despite the fact that insecticidal compounds from nature are preferred because they are environmentally safe. Future studies aimed in isolating and characterizing the active compounds from the plants is necessary. It is also necessary to develop plant based formulations to be used as altenatives in controlling the crop storage pests

Sweet potato microbial virus detection protocol and microbial infections control

Sweetpotato is an important food crop worldwide since it is drought tolerant and acts as a famine relief crop. However, its production is limited by viral, fungal and bacterial infections. Lack of rapid and sensitive techniques for detection of infections inhibits their control. Use of synthetic chemicals to manage microbial infections is not effective because apart from their potential danger to both humans and environment, they are unaffordable by most farmers. Moreover, because of pathogens resistance, most chemicals have become ineffective. In order to fully exploit the potential of the sweetpotato crop, there is a need to search for affordable, readily available, sustainable, and environmentally friendly means of managing the problems posed by these pathogens. Plants extracts have been reported to be safe, non-phytotoxic to humans, but effective against several plant pathogens. The aim of this study was to identify viruses infecting sweetpotato in western Kenya, develop a multiplex polymerase chain reaction (PCR) protocol for detection of major viruses of the crop, and evaluate efficacy of medicinal plant extracts for antimicrobial activity against the crop pathogens. Symptomatic sweetpotato vines from farmers’ fields were tested for ten viruses using NCM-ELISA. mPCR protocol for detection of Sweetpotato feathery monttle virus (SPFMV) and Sweetpotato chlorotic stunt virus (SPCSV) was optimized through variation of test parameters under standard PCR conditions. Extracts from Warburgia ugandensis, traditionally used to manage microbial infections, were tested for antimicrobial activity against sweetpotato infection pathogens using paper disk diffusion assay. Five viruses namely SPFMV, SPCSV, Sweetpotato mild mottle virus (SPMMV), Sweetpotato chlorotic fleck virus (SPCFV) and Cucumber mosaic virus (CMV) were detected. Eighty nine percent of samples had viral infection with over 80% showing multiple infections. Occurrence of CMV in Kenya was recorded for the first time. A rapid multiplex PCR protocol that simultaneously detects SPFMV and SPCSV was developed. The best amplification was obtained with 2.0 g of complementar cDNA template using the following parameters: one cycle at 95 ºC for 5 min followed by 35 cycles 96 ºC, 5 sec for denaturation; 63 ºC, 5 sec for primer annealing and 72 ºC, 30 sec for extension and a final extension at 72 ºC for 10 min. From the antimicrobial assay, ethyl acetate extract exhibited the highest (P! 0.05) antifungal and antibacterial activities compared to n-hexane and methanol extracts. Rhizopus stolonifer was more susceptible to ethyl acetate extract (inhibition zone = 24.5 mm) than Blitox which was used as a positive control. The minimum inhibitory concentration (MIC) for the isolates ranged between 12.5 to 200 µg/ml with the lowest MIC value of 12.5 µg/ml being observed with polygodial against Fusarium solani; warburganal against Aspergillus niger and F. solani; and mukaadial against Aspergillus niger. This study provided a quantitative assessment of viruses infecting sweetpotato in western Kenya and a simplified mPCR protocol for routine rapid detection of SPFMV and SPCSV. Scientific proof for the efficacy of extracts and isolates of W. ugandensis as antimicrobial agents against sweetpotato pathogens and perhaps other crop pathogens was also provided

Stored Grains Protection Activity of Ocimum Suave Extracts and Compounds on Larger Grain Borer

Post-harvest pests cause serious losses to agricultural products in Africa. The pests consist mostly of beetles or moths and infest the grains at the crop stage or during the storage. Larger grain borer, Prostephanus truncatus (Horn), causes maize-grain losses during storage ranging from 30% to greater 40% of total production in 6 months. It reduces germination potential of maize grain and increases the grain’s moisture content thus accelerating contamination by fungi and bacteria. The aim of this study was to determine the insecticidal extracts and compounds from Ocimum suave. Percentage mortality of the insects were recorded 1, 2, 14 and 21 days after treatment while adult emergence inhibition and weight loss prevention activities were recorded 42 days after treatment. The essential oil of the plant gave 75.4, 77.1 and 78.5% mortality after 7, 14 and 21 days respectively, while leaf powder gave 50.3, 63.7 and 66.6% mortality after 7, 14 and 21 days respectively. Betulinic acid gave 56.9 and 58.1% mortality 14 and 21 days after treatment respectively. The essential oil completely prevented the emergence of the insects and also completely prevented weight loss of maize grains. The findings from this study have provided scientific data to support the use of Ocimum suave to control insect pests. Further studies aimed at identification on plant materials which can be used in pest management are highly recommende

Detection of sweet potato viruses in Western Kenya, development of a multiplex PCR technique for simultaneous detection of major viruses and evaluation of medicinal plants for antifungal and antibacterial activities against the crop pathogens

Doctor of Philosophy in Chemistry, 2011Sweet potato is an important food crop worldwide since it is drought tolerant and acts as a famine relief crop. However, its production is limited by viral, fungal and bacterial infections. Lack of rapid and sensitive techniques for detection of infections inhibits their control. Use of synthetic chemicals to manage microbial infections causes is discouraged since they ar nonbiodegradable. The aim of this study was to identify viruses infecting sweet potato in western Kenya, develop a multiplex PCR protocol for detection of major viruses of the crop, and evaluate efficacy of medicinal plants for antimicrobial activity against the crop pathogens. Symptomatic sweet potato vines obtained from farmers’ fields were testes for ten viruses using NCM-ELISA. The mPCR protocol for detection of SPFMV and SPCSV was optimized through variation of test parameters under standard PCR conditions. Extracts from Warburgia ugandensis, Elaeodendron schweinfurthianum and Terminalia brownii, which are traditionally used to manage microbial infections, were fractionated using chromatographic methods to obtain pure compounds. Structures of isolates were determined using spectroscopic and physical methods. Extracts and isolates were tested for antimicrobial activity against Alternaria spp, Aspergillus niger, Fusarium oxysporum, F. solanum, Rhizopus stolonifer (fungi), Ralstonia solanacearum and Streptomyces ipomoeae (bacteria). Five viruses namely SPFMV, SPCSV, SPMMV, SPCFV and CMV were detected. Eighty nine percent of samples had viral infection with over 80% showing multiple infections. Occurrence of CMV in Kenya was recorded for the first time. An mPCR protocol was successfully developed that detects SPFMV and SPCSV. Phytochemical studies afforded 26 compounds including 7α-acetylugandensolide that was isolated from W. Ugandensis for the first time. All the methanol, ethyl acetate and n-hexane extracts of the three plants were active against one or more of the test organisms. Methanol extract of W. ugandensis exhibited significantly higher activity (24.50 mm) than positive controls against R. stolonifer. Eighteen out of the twenty six compounds isolated exhibited antimicrobial activity against one or more of the test pathogens at concentrations ≤200 µg/ml. Polygodial, warbuganal, mukaadial, ugandensidial, ugandensolide, deacetoxyugandensolide and muzigadial, exhibited low MIC (MIC ≤ 50 µg/ml) against one or more pathogens that was comparable to those exhibited by standard drugs. This study provided a quantitative assessment of viruses infecting sweet potato in western Kenya and a simplified mPCR protocol for routine rapid detection of SPFMV and SPCSV. Scientific proof for the efficacy of extracts of W. ugandensis, E. schweifurthianum and T. brownii as antimicrobial agents against sweet potato pathogens and perhaps other crop pathogens was also provided.Maseno Universit