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Copyright of Sultan Qaboos University Journal for Science is the property of Sultan Qaboos University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ogiri is one of the naturally fermented seasonings widely applied in soup as condiment. This study investigated the chemical composition, antioxidant and sensory qualities of ogiri fermented with mutant and non-mutant B. subtilis strains produced from Citrullus vulgaris. Bacillus subtilis strains isolated from spontaneously fermented melon seeds (C. vulgaris) were exposed to different Ultraviolent (UV) irradiations and Sodium Dodecyl Sulphate (SDS) at varying time intervals to obtain mutant strains. Eight (8) mutated strains of B. subtilis that produced high D-ribose metabolites were used for ogiri production. The DPPH (83.11 %), hydroxyl radical scavenging (49.41 %), FRAP (74.34 mgAAE/100g) and Fe2+ chelation abilities (86.72 %) of ogiri samples produced with B. subtilis mutant strain was higher than that of market sample (RTE00) values 76.06 %, 41.98 %, 54.32 mgAAE/100g and 72.74 %, respectively. Sample MIC64 had the highest fibre and protein contents (7.40 % and 26.42 %), respectively, while sample MSD51 had the highest phosphorous (3.73 %) and copper was detected in sample 30 (0.07 %). Sample MSD99 had the highest D-ribose yield (1.00 g/kg). The protein increased from 19.82 to 26.42 %, while sample (MIC21) has most acceptable sensory quality. Ogiri produced from mutant strains of B. subtilis have improved nutrient and antioxidant capacity hence, has potential for use as functional food. [ABSTRACT FROM AUTHOR]

In these research, the mineral and antinutrient content of cassava tubers (Manihot esculenta crantz) steeped in water from different sources for fufu production was investigated. It involved fermentation which was done by steeping peeled cassava tuber in water from five different sources (well, boiled, distilled, stream, tap) for five days. There were variations in the mineral content of both the fermented tuber, the mash and the fufu made from the different water sources with respect to the following minerals iron, sodium, zinc and magnesium, The mineral analysis shows a decrease in the mineral content of the fermented cassava tubers compared with the fresh cassava tuber with the magnesium content of the fresh cassava tuber which reduced from 428.53ppm to 309.21ppm for tubers fermented with stream water, 230ppm for tubers fermented with tap water, 288.46ppm for tubers fermented with boiled water, 228.52ppm for tubers fermented with distilled water. The antinutrient content decreased after fermentation with the tubers fermented with tap, stream and boiled having the lowest cyanide content reducing from 4.07b±0.16 to (2.44Mg) while fufu made with tap water had the lowest cyanide content(1.90Mg), cassava tubers fermented with tap water had the lowest phytate content of 2.476ab±0.00. Sensory evaluation was conducted on the fufu with regards to the following parameters Taste, Aroma, Texture, Appearance, and it was observed that the fufu prepared with well, distilled and tap water were most preferred, with regards to taste, appearance and textures respectively while the fufu made with boiled water had the highest numbers of dislike with regards to appearance, taste, texture and aroma. Cassava tuber steeped in tap water retained more of the nutrients with minimal antinutrient content and is therefore recommended for fermentation of cassava tubers for fufu production. [ABSTRACT FROM AUTHOR]

Cowpea bacterial blight (Xanthomonas axonopodis pv vignicola) is a devastating disease of cowpea in Nigeria. Accurate identification is the first step for an effective management option. Thus, X. axonopodis pv. vignicola isolated from cowpea (Vigna unguinculata (L.) Walp) grown in different Agro-ecological zones in Nigeria were characterized using morphological characteristics, biochemical and antibiotic sensitivity tests. Pot experiments were conducted on two susceptible lines of cowpea (IT90k -- 76) and (IT84s -- 2246 -- 4) in the screen house. In vivo infectivity studies were carried out to determine the effect of each of the X. axonopodis pv. vignicola isolate groups on the cowpea. All isolates from each of the agroecological zones were classified into Group 1 (light yellow) and Group 2 (brownish yellow) based on their morphological presentation on nutrient agar medium. Results from four of the biochemical test showed differences between the two morphologically different groups. Group 2 isolates showed a large zone of inhibition to a Lincomycin hydrochloride while isolates from Group 1 were not affected by the action of the same antibiotic. Blight symptom was only observed when the two types of isolates were combined and inoculated simultaneously. This study showed that there are two morpho-types of X. axonopodis pv. vignicola and their synergetic infectivity results in blight symptoms expression in cowpea. [ABSTRACT FROM AUTHOR]

Faecal samples collected from cattle in Abeokuta, south west Nigeria were analysed for E. coli counts, antibiotics susceptibility pattern of E. coli and the plasmid profile of E. coli isolates using standard techniques. E. coli were recovered from 30 samples representing 28.4% of 107 feacal samples of cattle collected. The faecal E. coli count ranges from 1.1 × 10³ to 9.0 × 10³ cfu/ml-1. The percentage prevalence of resistance to each antimicrobial agent tested were; Ampicillin, AMP (97%), COT (93%), Gentamicin, GEN (57%), Nalidicic acid, NAL (40%), Nitrofuratoin, NIT (93%), Cotrimoxazole, COL (20%), Streptomycin, STR (37%) and Tetracycline, TET (93%) The plasmid profile analysis of the E. coli isolates from cattle faeces shows a total of 18 different plasmid bands with molecular weight ranging from 2310 to 23632.83bp. The relatively high prevalence of resistance to antimicrobial agents exhibited by E. coli isolates from cattle faeces is an indication of the possible health risk that may occur as a result of the indiscriminate release of such faeces to the environment. [ABSTRACT FROM AUTHOR]

Objective: The present study is on the assessment of the phytochemical constituents and antimicrobial property of Coriolopsis polyzona against bacteria isolated from wastewater and leftover foods collected from restaurants within Akure metropolis, South West, Nigeria. Methods: Bacterial were isolated from waste water and leftover foods using standard microbiological techniques. Qualitative and quantitative analysis of phytochemical present in extract was also determined. Antimicrobial activity of extracts obtained from Coriolopsis polyzona was tested against the bacterial isolates using agar well diffusion method. Results: Quanlitative phytochemical analysis reveals the presence of saponin, tannin and cardiac glycosides in both methanol (ME) and acetone (AE) extracts of Coriolosis polyzona. The study also shows that the methanolic (ME) and acetone (AE) extracts obtained from Coriolopsis polyzona, a wild macrofungus, possess inhibitory potential against bacteria associated with wastewater and leftover foods. The diameter of inhibition zone obtained for ME ranged between 2.3 to 6.00mm while AE had a more pronounced diameter of inhibition of 4.00 to 9.6mm. Purified extracts from ME and AE had better antimicrobial effect with zones of inhibition that ranged between 6.00 to 15.30mm for AE and 5.30 to 8.00mm for ME. Partially purified fraction of AE has comparative antibacterial property with the two reference antibiotics; perfloxacin (7.00 to 20.30mm) and amoxycillin (5.00 to 26.3mm) used as positive control. Conclusion: The results from this study indicate that bioactive compounds with antibacterial property can be sourced from this underutilized macrofungus present in the wild. [ABSTRACT FROM AUTHOR]

The potential of lactobacilli isolated from Ogi, obtained from fermented composite grain, Zea may and Sorghum vulgare, to produce β-galactosidase was investigated. Three lactobacilli Viz: Lactobacillus fermentum, Lactobacillus plantarum and Lactobacillus brevis isolated from ogi were assessed for their ability to produce β-galactosidase. â-galactosidase activity was measured by the release of α-nitrophenol (ONP) from β-nitrophenol-β-galactopyranoside (ONPG). The production of β-galactosidase by the lactobacilli was highest at the pH range 6.5 to 7.6. Among the three lactobacilli isolates obtained from ogi, Lactobacillus fermentum exhibited better β-galactosidase production (249.78 µmole/ min/ml) at pH 7.5. Lactobacillus plantarum and Lactobacillus brevis had 153 µmole/min/ml and 142 µmole/min/ml respectively at the highest level of production. The present study reveals that lactobacilli isolated from Ogi is capable of producing appreciable quantity of β-galactosidase which can be used in addressing incidences of lactose intolerance in individuals. [ABSTRACT FROM AUTHOR]

Two varieties of Pleurotus sajor-caju, obtained from the wild and cultivated (on shredded corncobs) were separated into cap and stalk and analysed on dry weight basis. The proximate composition (g/100g) showed that both varieties were highly concentrated in crude protein. The cultivated cap (Cc) was found to accumulate higher concentration of crude protein (26.34%) and ash (10.37%) than the wild cap (Wc), which had higher crude fat (3.90%) and crude fibre (16.32%) concentrations while the wild stalk (Ws) contained the highest concentration of crude fibre (26.14%). Amino acid analysis showed the mushroom protein to be a rich source of nutritionally useful essential amino acids with leucine as the most abundant occurring in highest concentration (mg/g) in the Cc (64.8±0.24). Methionine and cysteine concentrations were low as confirmed by their chemical scores (0.29-0.59). There was a significant difference (P<0.05) in the distribution of amino acids in the mushroom varieties and parts. The total essential amino acid (TEAA) in the cultivated range between 42.91-43.69% while in the wild it was between 42.90-43.73 % of the total amino acid content. The amino acid concentration was a function of mushroom variety and part selected. [ABSTRACT FROM AUTHOR]

The edible mushroom Pleurotus sajor-caju, cultivated on corncobs and obtained from the wild, was assessed by nutritional indices. The protein efficiency ratios obtained for the rats fed stalk diet (2.16) and that of rats fed native P. sajor-caju cap diet (2.14) were not significantly different (P >or= .05) from one another but were lower than the casein control (2.50), whereas the value for the wild cap diet-fed rats (2.99) was significantly higher (P or= .05) from the control. Biochemical parameters analyzed include serum albumin, total protein, and hemoglobin. Serum albumin concentrations of both the cultivated and wild cap diet-fed rats were not significantly different (P >or= .05) from that of the control, whereas those of the two stalk diet-fed groups were significantly higher (P

Antioxidant and antimicrobial potentials of extracts obtained from four wild mushrooms, Termitomyces clypeatus (TCE), Termitomyces robustus (TRE), Lentinus subnudus (LSE) and Lenzites species (LZE) collected in Nigeria were investigated. LSE and LZE displayed good scavenging activity against 2, 2-Diphenyl-1-Picrylhydrazyl (DPPH) and ferrous ion radicals at concentration of 2 mg/mL. However, TRE and TCE exhibited better superoxide anion scavenging effect at 2 mg/mL. All extracts (TCE, TRE, LSE and LZE) had comparable scavenging effect on hydroxyl radicals as butylated Hydroxytoluene (BHT) used as control. Moreover, extracts from the wild mushrooms were able to inhibit the growth of all indicator organisms at concentrations between 12.5 mg/mL to 100 mg/mL. LSE and LZE, however, showed better antimicrobial effect on the indicator organisms. The results suggest that extracts obtained from the four wild mushrooms may serve as sources of new bioactive compounds with effective antioxidant and antimicrobial activity.

The use of herbal remedies had increased significantly in the last one decade in Nigeria. This has led to the production of herbal products with bogus claims. The microbial quality and antibacterial properties of two Nigerian herbal remedies with such claimed efficacy of curing all manners of microbial diseases were assessed. The herbal remedies were discovered to be contaminated with the following microorganisms: Bacillus subtilis, Bacillus coagulans, Bacillus cereus, Basidiobotrytis sp, Oedocephalum sp, Varicosporium sp and Articulospora inflata. Antibacterial analysis using the killing rate revealed that the herbal remedies had bacteriostatic and not bacteriocidal effect. Qualitative phytochemical screening of the herbal remedies revealed the presence of saponin, tannins, alkaloids, anthraquinone and cardiac glycosides which suggest possible antimicrobial effect. However, the presence of microbial contaminants in the herbal remedies suggests that they may serve as source of infection to end users.