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The microbiological and sensory profile soymilk-based juice treated with aqueous extract of Aframomum danielli (1%-3%-w/v) and stored at 27±2C for twenty four weeks were examined. Synthetic additives/preservatives, which have been in use over the years, are more expensive and mostly imported with hard earned scarce foreign exchange. Adequate research work into the production and utilization of indigenous food additives on a large scale has not been undertaken in developing countries. This work was therefore planned to ascertain the usefulness of extracts of A. danielli, a local spice, in stabilizing the microbiological quality of soymilk-based juice. Standard methods were used for the production of juice samples from pineapple, orange, carrot and milk from soybeans. They were blended together in equal proportion and thereafter treated with A. danielli extract (1.0% to 3.0%) and stored at 27+2C for twenty four weeks. Infrared spectrophotometer was used to identify functional groups in Aframomum danielli and hence the active components responsible for the stability of the juice. Standard AOAC method was used for microbiological analysis of treated and untreated samples. Consumer evaluation of juice samples was done using analysis of variance (ANOVA). Some of the active components of the spice identified are 4-amino-acetophenone, N,N-dimethyl-2-chloroacetoacetamide, 3-beta-acetoxy-5-etienic acid, 6,10-dimethylundeca-5,9,-diene2-one, Phenyl-3-buten and 4-Phenyl butanone. There were significant differences in the microbial counts of the treated and untreated samples. Treated samples experienced little or no growth over the period of storage. The results validate previous reports that A. danielli extract has great preservative potentials. There were significant differences (P < 0.5) for colour and overall acceptability of the samples. When A. danielli extract was added to soymilk-based fruit juice, the microbiological and sensory qualities were found to be better preserved than that of the untreated samples.

This study investigated the effects of the aqueous extracts of Aframomum danielli, Turmeric and Clove in sprouting of yam (Dioscorea rotundata) and sweet potato (Ipomoea batatas). The sliced tubers were dipped into the aqueous extracts of A. danielli, turmeric and Clove, each at concentrations of 5%, 10% and 15%. The tubers were allowed to stand in the solution for 5 and 10 minutes. Distilled water was used in the control samples. The yam slices were air dried after removal from the liquids, placed in paper boxes and incubated at room temperature (28.9 ± 4.0°C) and Relative Humidity of 44.6 ± 18.4 % for a period of six weeks (Bibah, 2014). Weight loss was determined by finding the difference between the initial and final weights and expressed as percentage weight loss. The results indicated that Turmeric treatments at different concentrations of 5%, 10% and 15% were more effective in reducing sprouting index at 5 minutes treatment time with values of 1.79%; 3.00% and 3.02% respectively. Clove treatment at 15%, 10% and 15% A. danielli treatment were more effective in controlling sprouting at 10 minutes treatment time for the yam tubers. There was no clear distinction in the effectiveness of each of aqueous extract of A. danielli, Turmeric and Clove in controlling sprouting at 5 and 10 minutes treatment time for sweet potato tubers.

This study was carried out to evaluate the effect of using the aqueous extracts of Aframomum danielli, Turmeric and Clove at different concentrations of 5%, 10% and 15% as pretreatments in controlling browning of yam (Dioscorea rotundata) and sweet potato (Ipomoea batatas). Colour measurements were carried out on the untreated (control) and pretreated yam and sweet potato slices, using reflectance spectroscopy. The L* and a* values obtained for the control samples were compared with those of the pretreated yam and sweet potato samples. The inhibition of enzymatic browning in the samples was indicated by an increase in the “L*” values which ranged from 81.60 to 62.66 for yam samples and from 81.52 to 62.03 for sweet potato samples; browning was also associated to a decrease in the “a*” values for all the samples, which ranged from 4.29 to -1.86 for yam samples and 4.02 to -2.46 for sweet potato samples. Aqueous extracts of Aframomum danielli at minimum concentrations of 5% and 10% were found to be effective in controlling browning reactions in the pretreated yam slices and sweet potato slices respectively.

Cassava bread was prepared by pre-gelling, battering and baking cassava flour to which were added, in moderate amounts, sugar, yeast solution and edible oil. Baking was at 215 degrees C for 40 min. No mould was isolated from the cassava bread and the mean value of aflatoxin B1 (AFB1) for the three subsamples of cassava bread was 0.03 microgram/kg. The cassava tuber (Manihot esculenta Crantz), which was used for the production of cassava bread had an initial AFB1 level of 1.91 micrograms/kg and the dominant mycoflora were Penicillium oxalicum, Aspergillus flavus, Fusarium spp and some unidentified fungi.

Garcinia kola, (a herb grown in Nigeria; calorific value 358.54 k.cal/100 g) inhibited in vitro lipid peroxidation of rat liver homogenate in a dose dependent manner. The inhibitory activity of G.kola was not affected by heating (100 degrees C/10 min). The antioxidant component of G.kola was soluble in aqueous and ethanolic media. The active component(s) in G. kola responsible for its inhibitory activity on lipid peroxidation is tentatively identified as isoflavones.

Sodium metabisulphite and hydrogen peroxide alone or in combination with heat (50-70 degrees C) were found to be effective in degrading aflatoxin B1 (AFB1) in lafun and gari. Hydrogen peroxide (H2O2) at a concentration of 3% in the aqueous phase gave a 12.5% degradation of aflatoxin B1 in lafun and at 50 degrees C, degradation levels of 25% and 50% were obtained with 6.0 and 9.0% H2O2, respectively. When sodium metabisulphite was applied during the production of gari (a fermented cassava product heated to 50-70 degrees C during production) AFB1 degradation levels were found to be 65.8%, 60.9%, 41.5% and 36.6%, respectively, for sodium metabisulphite levels of 1.0%, 0.8%, 0.5% and 0.3%.

Non-commercial spices and herbs Tetrapleura tetrapetra, Triumfetta cordifolia, Garcina kola, Monodora myristica and Xylopia aethiopica at 0.08 to 0.32% (w/v) decreased the mycelial weight of Aspergillus parasiticus NRRL 2999 in yeast extract/sucrose broth by up to 68%. Aflatoxin production, monitored with ELISA, was most effectively decreased, from 97 to 23 μg/ml, when the extract of G. kola was added at 0.32% (w/v).

Thirty-six out of 120 isolates of coagulase-positive (c.p.) and coagulase-negative (c.n.) staphylococci isolated from clinically healthy and sick goats were characterized to be of animal origin on the basis of beta-haemolysin production and not a fibrinolysin (Minett, 1936; Elek and Levy, 1950; Marandon and Oeding, 1966), although the specific animal reservoir could not be determined. There was a correlation between beta-haemolysin production on 7 per cent human blood agar and 7 per cent sheep blood agar. "hot-cold" lysis phenomenon (Buxton and Fraser, 1977) was observe in 7.5 per cent of the isolates. Isolates characterized show single and multiple antibiotic resistance (Adegoke, 1981).

Nine of 11 caprine strains of Staphylococcus aureus examined belong to biotype C. They were typable serologically using antisera developed for typing human strains of Staphylococcus aureus. H2 was found to be the dominant thermostable antigen whilst 1 and 0 were the most common thermolabile antigens. Some strains possessed protein A and poly A beta (beta-glucosaminyl ribitol teichoic acid). Phage typing of the strains was achieved with an international set of phages for typing human strains of Staphylococcus aureus and they belong to phage groups II, and the mixed group.

A total of 169 house rats were killed in different households distributed within five localities of Ibadan. A wide range of parasites were encountered. The flea, Ceratophylus fasciatus was the commonest ectoparasite found. Trichostrongylus columbriformis eggs were the commonest nematode and Hymenolepis diminuta the only cestode. Escherichia coli was the commonest bacterium found. The incidence of helminthiasis, especially H. diminuta, was generally high among rats trapped in the villages and the indigenous areas of the city. One hundred and twenty eight (128) of the rats possessed Trypanosoma lewisi infection, seventy one (71) had Anaplasma marginale while fifty seven (57) had Babesia microti infection. The public health importance of some of the parasites found is discussed.

In the course of a survey of urine samples collected over a period of 12 months from male and female patients of different socio-economic backgrounds in Ibadan, Esch. coli, Klebsiella spp. Pseudomonas aeruginosa, Proteus spp., Staphylococcus aureus and Candida albicans were the most common pathogens isolated. The bacteria were commonly sensitive to the cephalosporins, kanamycin, ampicillin and cotrimoxazole in decreasing order of sensitivity.

Whilst Staphylococci isolated from goats may possess "bound" coagulase, they do not seem to produce "free" coagulase. Of the 85 isolates that gave positive slide-coagulase test with human plasma, only 13 (15.3%) gave positive tube-coagulase tests. When goat's plasma was used, 78 isolates gave positive slide-coagulase test and 9 (10.3%) gave positive tube-coagulase tests. 16 (13.22%) of the isolates which showed complete haemolysis on human blood agar, gave positive slide-coagulase tests. The 120 isolates obtained from clinically healthy and sick goats were tested for sensitivity to 12 chemotherapeutic agents. They were most sensitive to kanamycin, cephaloridine and ampicillin. Resistance to tetracycline and streptomycin was prominent. The minimum inhibitory concentration (MIC) of on the antibiotics to which the isolated were resistant ranged from 500, 250, 125 to 0.0448 mcg/ml for streptomycin and chloramphenicol whilst the (MIC) of the isolates for tetracycline and penicillin G ranged from 5.0, 2.5, 1.25 to 0.009 mcg/ml and units/ml respectively.