Showing papers by "University of Nigeria, Nsukka published in 1995"

Preliminary studies of the antifungal activities of some medicinal plants against Basidiobolus and some other pathogenic fungi.

Abstract: Summary. The antifungal activities of extracts of 10 medicinal plants collected from south-eastern parts of Nigeria were tested against seven pathogenic fungi using the broth dilution and agar plate methods. All the extracts at 1:10 dilution inhibited the growth of Basidiobolus haptosporus and B. ranarum but did not inhibit that of Aspergillus fumigatus, Geotrichum candidum and Candida albicans. While extracts from Piper guineense, Ocimum gratissimum, Moringa oleifera and Erythrophleum suaveolens inhibited the growth of Trichophyton rubrum and T. mentagrophyies, those from Jatropha curcas, Mitraccrpus villosus. Azadirachta indica and Gongronema latifolium failed to do so at 1.10 dilution. Extract from Piper sp. was also able to inhibit the growth of B. haptosporus at a concentration as low as 1:80 dilution followed by those of Ocimum and Rauvolfia spp. at 1:40 dilution. These results indicate possible use of certain plant extracts in the treatment of subcutaneous phycomycosis in humans and animals. Zusammenfassung. Die antimyzetische Aktivitat von zehn offizinellen Pflanzen, in den sudostlichen Landesteilen von Nigeria gesammelt, gegen sieben pathogene Pilze wurde im Dilutionstest und im Agardifusionstest untersucht. Samtliche Pflanzenextrakte hemmten in der Verdunnung 1:10 das Wachstum von Basidiobolus haptosporus und B. ranarum, nicht jedoch das Wachstum von Aspergillus fumigatus, Geotrichum candidum und Candida albicans. Extrakte von Piper guineense, Ocimum gratissimum, Moringa oleifera und Erythrophleum suaveolens hemmten in der Verdunnung 1:10 das Wachstum von Trichophyton rubrum und T. mentagrophytes. Extrakte von Jatropha curcas, Mitracarpus villosus, Azadirachta indica und Gongronema latifolium zeigten keine Hemmwirkung auf diese Pilze. Der Extrakt von Piper sp. hemmte noch in der Verdunnung von 1:80 das Wachstum von B. haptosporus. der von Ocimum und Rauvolfia spp. noch bei einer Verdunnung von 1:40. Diese Ergebnisse weisen auf die Moglichkeit hin, gewisse Pflanzenextrakte zur Behandlung subkutaner Zygomykosen bei Mensch und Tier einzusetzen.

Production of raw starch digesting amylase by Aspergillus niger grown on native starch sources

Abstract: Aspergillus niger isolated from rotting cassava produced raw starch degrading amylase on cassava, maize, sorghum and soluble potato-derived starch as the sole carbon source without prior gelatinisation. Maximum activity of the amylase was attaired using cassava starch as substrate. The crude enzyme solution which comprised a mixture of raw and non raw starch digesting amylase degraded both cereal and tuber or root starches significantly. Source of assay starch significantly influenced raw starch digesting activity. Optimum pH for the raw starch degrading and the extracellular amylase were 6.0 and 3.5-4.0, respectively. However, both enzyme activities appeared to be uninfluenced across a relatively broad pH range 3.0-7.0. No correlation was found between the capacity of starch to induce expression of the enzyme and its susceptibility to enzyme digestion. The adsorbability of the various starches to raw starch digesting amylase was directly related to their digestibility.

Antimicrobial Activities of the Constituents of Garcinia Kola Seeds

Abstract: Antimicrobial activity of seed extracts derived from Garcinia kola was studied in vitro. The seeds were successively extracted with petroleum ether, 70% ethanol and water. The ethyl acetate fractio...

Rainfall parameters influencing erosivity in southeastern Nigeria

Abstract: Rainfall erosivity was characterized for the Guinea Savanna, Forest and Coastal belts of southeastern Nigeria (4° and 7°N; 6°30′ and 9°30′E). The highest maximum rainfall amounts ranged from 117 to 183 mm per rain event whereas the maximum 6-minute intensities ranged from 191 mm h−1 to 254 mm h−1 Advanced storms were dominant in the region. The values of the Kowal and Kassam kinetic energy equation (designated Ek were 1.6 times higher than the values obtained using Wischmeier and Smith's equation (designated E). Compound rainfall erosivity used were the EI30, KE ≥ 25mm h−1, AIm, Ek I30 and Ek Em. The mean annual erosivity values using the EI30 index ranged from 12,814 to 18,611 MJ · mm/ha · h. The KE ⩾ 25mm h−1 ranged from 141 to 249 MJ ha−1, the AIm from 849 to 1421 cm2 h−1, the Ek I30 from 16,697 to 29,610 MJ · mm/ha · h and Ek Im from 32,752 to 62,238 MJ · mm/ha · h. Rainfall erosivity approximations from rainfall amounts using indices from Roose and Arnoldus may be converted to Sl units (Foster et al.) by multiplying by a factor of 17. Rainfall erosivity differences were more pronounced between the Guinea Savanna and Forest or Coastal belts than between the Forest and Coastal belts. Erosivity is higher in the Forest or Coastal belts than the Guinea Savanna belt. The high erosivity of rains in southeastern Nigeria can be attributed to heavy storms of comparatively high intensities and, often, long duration. The magnitude of rainfall erosivity provides a useful insight into the causes of the catastrophic erosion problems in southeastern Nigeria.

Taenia solium cysticercosis and human taeniasis in the Nsukka area of Enugu State, Nigeria.

Abstract: The prevalence of Taenia solium cysticercosis in slaughter pigs and of taeniid ova in hospital patients were determined in the Nsukka area of Enugu State, Nigeria, in March 1986-September 1988 and May 1986-May 1988, respectively Cysticercus cellulosae were detected in the pigs by ante-mortem examination of the pigs' tongues and detailed post-mortem examination of the dressed pig carcasses using standard meat-inspection procedures Human infection was assessed by examining iodine-stained stool samples collected from patients from one selected hospital in the study area Over 20% (483) of the 2358 trade pigs examined were found infected with C cellulosae Most of the cases were generalized, all the musculature being heavily infested with live cysticerci The age and sex of the pig and the season of the year in which it was examined had no significant effect on the occurrence of cysticerci in the animals (P > 001) but there was a highly significant year-to-year decrease (P 30 years The epidemiological factors which might have influenced these results are identified and discussed, and suggestions are made for the control of this important zoonosis

The adverse effects of long-term cassava (Manihot esculenta Crantz) consumption.

Abstract: Cassava (Manihot esculenta Crantz) is an important dietary staple for more than 500 million people in developing countries. People eat 60% of the cassava produced and one third of the harvest feeds animals. All cultivars of cassava contain the cyanogenic glucoside, linamarin, but in different concentrations. The roots of those cultivars with high cyanogenic content are processed to reduce the level of linamarin, because linamarin is hydrolysed in the intestinal tract of both men and animals by microbial flora and HCN is released. Researchers have implicated the sublethal levels of HCN produced on ingestion in the development of a number of metabolic diseases in both man and animals when cassava-based diets are consumed over a long period of time but the release of HCN cannot fully explain the metabolic effects of ingested linamarin. A significant amount of linamarin remains intact and is excreted in the urine. It appears that the intact linamarin inhibits Na+K+ATPase causing electrolyte imbalance within the cell. This phenomenon is exacerbated by free radicals generated by the hypoxia/normoxia cycles created by cyanide released from linamarin, which cause lipid peroxidation and cell membrane damage. When the supply of endogenous thiosulphate is adequate, cyanide plays a very minor role in the development of lesions. The amount of damage is related to the quantity of linamarin routinely ingested at sublethal levels. There appears to be species differences in the rate of the development of diseases and the intensity.

Content of antinutrients and in vitro protein digestibility of the African yambean, pigeon and cowpea.

Abstract: The protein, trypsin inhibitor (TI), tannin, phytate, phytic acid phosphorus and in vitro protein digestibility (IVPD) of cultivars of the African yambean (Sphenostylis stenocarpa) — AYB, pigeon pea (Cajanus cajan) — PP and cowpea (Vigna unguiculata) — CP were determined. The protein content of CP (24–28.0%) was higher than those of PP (21–22.5%) and AYB (21–22.5%). The cream and speckled AYB contained more TI (30.9 and 25.3 mg/g) than PP (7.5–14.1 mg/g) and CP (9.8–20.5 mg/g). Apart from the white CP cultivar, they contained more tannin (1.24–1.42 mg/g) than PP (0.14–0.97 mg/g) and AYB (0.71–1.17 mg/g). Phytate was lowest in the AYB (6.30–7.49 mg/g) than PP (8.31–11.31 mg/g) and CP (8.40–9.92 mg/g). Phytic acid contributed 67–74% of the phosphorous in the AYB, 66–75% in PP and 54–59% in CP. The IVPD of the AYB (73.3±0.7%) was significantly lower (p<0.05) than those of PP (76.34±0.2%) and CP (77.8±0.4%). There was a significant negative correlation between TI and IVPD (r=−0.63,p<0.05). There was no significant correlation between IVPD and phytate and tannin contents. There was a positive correlation between protein content and IVPD (r=0.69**) for the legumes under study. These legumes may pose no serious problems to populations consuming them especially when heat treatment is applied before consumption.

Effects of air rest periods on malting sorghum response to final warm water steep

Abstract: The effects off various lengths of air rests on response off malting sorghum main root length, malting loss, diastatic activity, α- and β-amyloytic activity and extract to final warm water steep at 40°C was investigated. Grains were steeped in distilled water for a total of 48 h at 30°C with a 6 h final warm water steep under four different cycles incorporating 1, 2, 3 or 4 h air rest periods. All malt quality properties evaluated were significantly affected by the length of air rest, the cultivar and their pair-wise interactions. Main rootlet length and malting loss reduced progressively as the length of air rest increased. Reducing power, α- and β-amylolytic activity and extract generally increased as the length of air rest was increased for both sorghum cultivars ICSV 400 and KSV 8 examined. The steep cycle incorporating 3 h length of air rest was found by experiment to give the optimum levels of malt quality indices analysed while at the same time causing considerable reduction in average main rootlet length and total malting loss for both grain cultivars.

The effects of Icacina trichantha tuber extract on the nervous system

Abstract: The tuber of Icacina trichantha was extracted with 50% methanol and concentrated to dryness in vacuo to give a yield of 5.6% w/w. The extract induced sleep in rats treated with high doses (400–1000 mg/kg i.p.). The LD50 of the extract was 671 mg/kg i.p. It potentiated pentobarbitone sleeping time in rats dose-dependently and also induced significant local anaesthetic effects in guinea-pigs. The extract was able to give 80% protection to rats poisoned with pentylenetetrazole but failed to protect rats from strychinine poisoning. It induced significant dose-dependent analgesia in rats and showed significant muscle relaxant activity in mice.

Fluconazole in the therapy of tropical deep mycoses

Abstract: Summary. A clinical study was conducted to test the efficacy of fluconazole in the treatment of tropical deep mycoses. Two out of four patients with zygomycosis due to Conidiobolus coronatus who were treated with the drug were completely cured; the other two patients exhibited considerable improvement but could not be followed up. Two patients with eumycetoma, one due to an Acremonium sp. and one due to Pseudallescheria boydii, were treated successfully, whereas another patient with a eumycetoma caused by an unidentified fungus could not be followed up. A complete cure was achieved with one patient with African histoplasmosis and one with candiduria. A case of cerebral phaeohyphomycosis due to Cladesporium sp. showed some improvement but the patient later developed meningitis and died. Zusammenfassung. Zur Bewertung des Fluconazols in der Therapie tropischer tieflokalisierter Mykosen wurde eine klinische Studie durchgefuhrt. Von vier durch Conidiobolus coronatus verursachten Zygomykosen konnten zwei vollstandig ausgeheilt werden; bei den beiden anderen wurde deutliche Besserung beobachtet, doch konnten sie nicht nachkontrolliert werden. Zwei Eumyzetom-Falle, verursacht durch Acremonium sp. bzw. Pseudallescheria boydii, konnten erfolgreich behandelt werden; ein dritter Fall mit einem nichtidentifizierten pilzlichen Erreger konnte nicht nachkontrolliert werden. Eine Afrikanische Histoplasmose und eine Candidurie konnten mit Fluconazol voll ausgeheilt werden. Bei einem Patienten mit zerebraler Phaeohyphomykose durch Cladosporium sp. zeigte sich Besserung, doch entwickelte sich spater eine Meningitis, und der Patient verstarb.

Testing the goodness of fit of infiltration models for highly permeable soils under different tropical soil management systems

Abstract: The Kostiakov, modified Kostiakov (A), modified Kostiakov (B), Philip, modified Philip (A) and modified Philip (B) infiltration models were tested for their ability to describe water infiltration into highly permeable sandy soils from the Nsukka plains of SE Nigeria. Infiltration data were obtained on field plots with the following management systems: tilled-mulched, tilled-unmulched, untilled-mulched, untilled-unmulched and continous pasture. On all treatments, the cumulative infiltration values predicted by the classical Kostiakov, Philip and modified Philip (A) models deviated most from the experimental data. The other models produced values that agreed very well with the measured data. Considering the ease of determining the fitting parameters it is proposed that on soils with high infiltration rates, either the modified Kostiakov model (I = Kta + Ict) or modified Philip model (I = St12 + Ict), (where I is cumulative infiltration, K is the time coefficient, t is the time elapsed, a is the time exponent, Ic is the steady infiltration rate and S is the soil water sorptivity), be used for routine characterisation of the infiltration process.

Feeding of lactic acid-fermented high nutrient density weaning formula in paediatric settings in Ghana and Nigeria: Acceptance by mother and infant and performance during recovery from acute diarrhoea

Abstract: A period of acute diarrhoea in infants is often associated with anorexia and weight loss. Catch-up growth is, therefore, necessary and this depends very much on the type of food, in terms of nutrient density, protein quality and digestibility, given to the child. Fermented (F) and non-fermented (NF) maize-soybean porridges of increased nutrient density were formulated and compared with traditionally fermented maize-only porridge (P) for acceptability using mothers in peri-urban Ghana as well as urban Nigeria as subjects. Subsequently, infants hospitalised in paediatric wards for acute diarrhoea, from the same communities in both countries, were assigned randomly to one or other of the three porridges. Infant subjects in all cases fell within the ages of 6-15 months. Complementary to regular breast-feeding, infants could consume as much porridge as they wanted and their total daily consumption was interpreted as an indication of acceptance. Although mothers in both the environments of Ghana and Nigeria rated P as more acceptable than F and NF, no significant difference was recorded in the quantitative intake by infants of the three formula groups. By adding enzyme-rich cereal malt flour (at the 1-5% level by weight) as a viscosity-thinning agent to F and NF porridges, it was possible to feed these porridges to infants at total solids concentration levels of 20-25% (wet basis) which is approximately double the solid matter content of the P porridge. Consequently, the daily nutrient intake by infants consuming F and NF porridges was considerably higher compared to the P porridge group. It is concluded that the concept of high nutrient density weaning foods is a feasible vehicle for an improvement of nutrient supply to infants.

Effects of air rest period on the mobilisation of sorghum reserve proteins

Abstract: The influence of air rest treatment period on the mobilisation of storage proteins of two improved Nigerian sorghum cultivars ICSV 400 and KSV 8 was evaluated. Grains were steeped in distilled water for a total period of 48 h at 30°C with a 6 h final warm steep at 40°C under four different cycles incorporating 1, 2, 3 or 4 h air rest period respectively. Cold water soluble protein, cold water soluble protein modification index, total cold water solubles, total free alpha amino acid nitrogen, carboxy-peptidase and proteinase activities were determined after 6 days malting. All these protein modification indices were highly significantly affected by length of air rest and cultivar, plus their pair-wise interactions. The levels of all these variables were also higher in sorghum cultivar ICSV 400 compared to KSV 8 except for proteinase activity. Significant differences in grain storage protein complexity and structure coupled with probable differences in key proteinase iso-forms are advanced as possible explanation for the higher proteinase activity recorded in KSV 8 malts.

Certain functional properties of gums derived from some lesser known tropical legumes (Afzelia africana, Detarium microcarpum andMucuna flagellipes)

Abstract: Gum was extracted from some lesser known tropical legumes —Afzelia africana, Detarium microcarpum andMucuna flagellipes. The extracts were evaluated for some functional properties. At a constant shear rate the apparent viscosity of the gums was directly proportional to the gum concentration. At 2% concentration, the gum dispersions showed an apparent viscosity of 41.24, 115.05 and 145.14 cps forA. africana, D. microcarpum andM. flagellipes gums respectively, measured at 174/sec and 25±1°C with the NV sensor of Haake rotovisko viscometer. All the gums were found to contain D-galactose as a major monosaccharide. In addition, the presence of D-mannose, and D-glucose were indicated in bothD. microcarpum andM. flagellipes while L-rhamnose, was indicated only inA. africana. A. africana showed significantly (p<0.05) lower water absorption capacity and gelation properties thanD. microcarpum andM. flagellipes. All the gums showed good emulsion properties. Emulsions ofM. flagellipes gum showed little response to pH changes whileA. africana andD. microcarpum gum showed better emulsion properties at acid pH than at alkaline pH.

Isolation and characterization of a d-glucose/xylose isomerase from a new thermophilic strain Streptomyces sp. (PLC)

Abstract: A thermostable d-xylase isomerase from a newly isolated thermophilic Streptomyces sp. (PLC) strain is described. The enzyme was purified to homogeneity. It is a homotetramer with a native molecular mass of 183 kDa and a subunit molecular mass of 46 kDa. The enzyme has a K m of 35 mM for d-xylose and also accepts d-glucose as substrate, however, with a tenfold higher K m (0.4 M) and half the maximum velocity. Both the activity and stability of this d-xylose isomerase depend strongly on divalent metal ions. Two metal ions bind per subunit to non-identical sites. Mg2+, Mn2+ and Co2+ are of comparable efficiency for the d-xylose isomerase reaction. Con2+ is the most efficient cofactor for d-glucose isomerization. The enzyme remains fully active up to 95°C. The activity decreases at 53°C in the presence of Co2+ and Mg2+ with a half-life of 7 and 9 days respectively. In the presence of Mn2+ the enzyme activity remains constant for at least 10 days and at 70°C 50% of the activity is lost after 5 days.

Microbiological studies on cases diagnosed as typhoid/enteric fever in south-east Nigeria.

Abstract: Eight hundred and nine patients suspected of having typhoid/enteric fever were investigated. Enteric fever bacilli (Salmonella typhi and S. paratyphi) were cultured from stool samples of 128 (16%) patients. Serological evidence of typhoid fever was obtained in 83 (13%) of 620 of the patients examined by the Widal test. The antibody titres ranged from 1:160 to 1:1280. A higher proportion of paratyphoid infection over typhoid infection was recorded both by culture (56%) and by the Widal test (63%). The predominant serotype was paratyphi C. Non-typhoid Salmonellae were recovered from stool samples of 60 patients, comprising five serovars, namely, S. typhimurium-22 strains, S. enteritidis-15, S. hardar-9, S. virchow-5, S. bredeney-3, and 6 non-typable strains. Shigella sonnei and S. flexneri were detected in diarrhoeic and semi-formed stools of 19 (2.3%) of the typhoid suspects. It is clear from the results of the study that though typhoid is endemic in South-East Nigeria and the number of cases may rise at certain periods of the year, the news of a current wave of epidemic of typhoid seem unfounded.

Evaluation of the Chemical Composition of Manures from Different Organic Wastes and their Potential for Supply of Nutrients to Tomato in a Tropical Ultisol

Abstract: Manures (sewage sludge, swine, rabbit and poultry manures) from four farm or homestead wastes were analyzed for their chemical composition and were compared with NPK fertilizer for their ability to supply nutrient elements to tomato plants under field conditions. The organic manures varied considerably in their initial content of nutrient elements, their effects on soil pH and in their release of nutrients for tomato absorption. NPK fertilizer appeared more efficient than the organic manures in supplying N, P and K, at least in the short run, while the organic manures had an advantage in the supply of other macro- and micro- nutrient elements not contained in NPK fertilizer. There were variabilities in the efficiency of supply or uptake of the elements contained in the various manures. Under the conditions of the experiment, the recommendable manure rates at which tomato gave good growth were 10 t ha−1 for swine manure, 20 t ha−1 for sewage, a range of 10 to 20 t ha−1 for rabbit and poultry manur...

Protein quality of some Nigerian traditional diets based on the African yambean (Sphenostylis stenocarpa) and pigeon pea (Cajanus cajan)

Abstract: The protein quality of Nigerian traditional diets based on the African yambean (AYB) and pigeon pea (PP) were performed by in vivo and in vitro bioassays. The individual foods were processed, cooked, dried and mixed to resemble the traditional diets. Weanling male Wistar rats (45–55 g) were used for the bioassay. The rats were fed ad libitum for 35 days of which 28 days were for growth and 7 days for N-balance. All the eleven diets including casein (control) provided 1.6 g N/100 g diet. The parameters tested include PER, growth, N-balance, BV, NPU and apparent digestibility (AD). The rats fed the AYB diets, except AYB: Agidi (Ag), showed superiority in most of the parameters tested. There were significant positive correlations between PER and NPU (r=0.925;p<0.001); PER and AD (r=0.908;p<0.001); PER and body weight gain (r=0.969;p<0.001). The in vitro protein digestibility of the diets was significantly correlated (r=0.80;p<0.01) with the in vivo apparent digestibility. These parameters were used to rank the various diets. Crayfish protein was a better supplement to legume/cereal or legume starchy staple mixtures than leguminous oil seed. However, supplementation of PP: steamed corn (SC) diet with crayfish did not prove beneficial. The result showed that diets based on the African yambean, an under-exploited legume, are nutritious. The need for its reintroduction into the fare of the populace through increased production and appropriate processing technology is stressed. The results of this study can form a base for the standardization of Nigerian diets based on these legumes.

HEAT SENSITIVITY, OPTIMUM pH AND CHANGES IN ACTIVITY OF SORGHUM PEROXIDASE DURING MALTING AND MASHING

Abstract: Peroxidase activity was demonstrated in dry and germinating sorghum seeds. The specific activity increased about 14-fold during malting for a 96-hour period. On the average about 41% of peroxidase activity was located in the endosperm, and the remaining 56% in the acrospire and rootlet of sorghum malt. The crude enzyme extract retained 77%, 17.5% and 7.6% of activity after heating at 60°, 70° and 80°C, respectively. More than 50% of the peroxidase activity in the finished malt survived mashing at 65°C. Optimum activity was recorded at pH 5.5 which falls within the observed pH range of sorghum worts. The level of residual peroxidase activity in the wort differed with sorghum species.

Antihepatotoxic and Antimicrobial Activities of Harungana madagascariensis Leaf Extracts

Abstract: The antimicrobial and antihepatotoxic activities of the leaf extracts of Harungana madagascariensis were tested in vivo and in vitro. The leaf was extracted with petroleum ether and 70% ethanol, re...