Open Access Original Research Article

Effects of Nigella sativa Linn. Oil on Gut Bacteria and Liver Function Status of Albino Wistar Rats

F. Oluwafemi, P. Ojo, A. L. Kolapo, S. O. Oluwalana

Asian Food Science Journal, Page 1-7
DOI: 10.9734/afsj/2019/v13i130093

Background: Nigella sativa oil (NSO) has been suggested for use in several food and pharmaceutical applications due to its bioactive contents.

Objectives: The present study investigated the effects of 14 µl/g body weight dosage of NSO on body weight, gut microflora and liver function status (LFS) of albino wistar rats. Phytochemical analysis of NSO extract was done.

Materials and Methods: Sixty male Wistar rats were randomly assigned into two groups: 14 µl/g body weight of NSO was administered to group A while group B was given an equal volume of distilled water. Five rats provided baseline data for weight, the microbial counts and LFS in a 12-weeks experiment. At two weeks interval, five rats were sacrificed from each group and their intestinal contents were used for the microbial count (Viable, Coliform, E. coli, Staphylococci and Lactic acid bacteria (LAB)) assessment and the blood samples for LFS study.

Results: Nigella sativa oil showed the presence of alkaloids (0.083 mg/g), flavonoids (0.302 mg/g), saponins (0.325 mg/g), terpenes (0.138 mg/g), steroids (0.152 mg/g), tannins (0.008 mg/g) and terpenoid (0.138 mg/g). In both groups, the weight of rats continued to increase from the onset of the study, but between 10th and 12th week, non-significant (p>0.05) weight reduction was observed from 191.72±3.23 g to 189.30±4.71 g in the treatment group. Baseline Viable, Coliform, E. coli, Staphylococci and LAB counts (x 106 CFU/g) were 160, 146, 55, 23, and 154 respectively. Sequel to intake of NSO for twelve weeks, the microbial counts (x 106 CFU/g) were respectively 49, 38, 27, 11, and 318. Blood samples also showed a significant (p<0.05) reduction in LFS for Aspartate aminotransferase (78.48 to 60.06U/L), Alanine aminotransferase (30.80 to 18.54 U/L), Alkaline phosphatase (97.00 to 79.34U/L), and Bilirubin (0.52 to 0.20 U/L).

Conclusion: Beneficial effects of NSO at the investigated dosage of 14 µl/g body weight has been demonstrated as no toxicological effect was observed.

Open Access Original Research Article

Nutritional Composition, Microbiological Quality and Sensory Properties of Kunu-zaki Produced from Millet and Tigernut Blend

K. M. Adaramola-Ajibola, A. R. Osaloni, O. C. Arijeniwa

Asian Food Science Journal, Page 1-10
DOI: 10.9734/afsj/2019/v13i130094

Aims: To investigate the effect of supplementation of kunu-zaki with milk on its nutritional and microbiological qualities and overall acceptability.

Place and Duration of Study: Department of Science Laboratory Technology, Faculty of Applied Sciences, Rufus Giwa Polytechnic, Owo, between April, 2019 and July, 2019.

Methodology: The two (2) Kunu-zaki blends were produced by traditional fermentation method, thereafter, they were screened for the presence of microorganisms using pour plate method while colonial characteristics and biochemical tests (Sugar utilization, catalase, coagulase, oxidase) were done to confirm the identity of the organisms. The proximate composition (moisture, protein, lipid, ash, fibre and carbohydrate) of the samples were assayed using standard procedures. The sensory properties of the Kunu-zaki were assessed using a trained panel. Data were analyzed statistically using SPSS version 17.0 and the means separated using Duncan Multiple Range Test.

Results: Coliforms and Enterobacteriacea were not found in the enriched and control Kunu-zaki samples. However, the highest total heterophilic bacterial count (107x103 cfu/ml) and lactic acid bacterial count (131 x103 cfu/ml) were found in sample B while the least counts were found in the control sample with 92 x103 cfu/ml and 122 x103 cfu/ml total bacterial and lactic acid bacterial counts respectively. Further, the highest fungal count was found in control sample (67 x103 sfu/ml) while the least count were observed on sample B (52 x103 sfu/ml). The control sample had the lowest pH 4.65 while sample C had the highest pH of 5.95. Also, the TTA ranged between 0.57% I sample C and 0.83% in control sample. A total of six (6) bacteria and six (6) fungi were isolated from the freshly prepared kunu-zaki-tigernut milk blends, they were Bacillus subtilis, Bacillus licheniformis, Micrococcus luteus, Lactobacillus acidophilus, Lactobacillus plantarum, Streptococcus species, Geotrichum candidum, Saccharomyces cerevisiae, Aspergillus niger, Rhizopus stolonifer, Fusarium and Penicillium species. The crude protein, moisture content and fat of the enriched Kunu-zaki were significantly (p≤0.05) higher than the control sample. Also, there was a reduction in fibre, ash and carbohydrate content of the enriched Kunu-zaki product compared with the control sample. The enriched Kunu-zaki samples had higher level of potassium, magnesium and phosphorus than the control Kunu-zaki while they had lower calcium and sodium concentrations. Kunu-zaki-tigernut milk blends had comparable rating to the control in appearance and aroma but had a higher rating for taste and overall acceptability.

Conclusion: The enrichment of Kunu-zaki with tigernut milk had significant elevating effect on the nutrition and sensory properties of the Kunu-zaki and its overall acceptability.

Open Access Original Research Article

Characteristics of Coconut (Cocos nucifera) Flour and Its Application in Cake

Newlove A. Afoakwah, John Owusu, Victoria Owusu

Asian Food Science Journal, Page 1-11
DOI: 10.9734/afsj/2019/v13i130095

Aims: The aim of the study was to evaluate the physicochemical, sensory and functional properties of coconut flour (CF), coconut wheat composite flour (CWCF) and Cake produced from CF and CWCF.

Methodology: Flour was prepared from matured ripe coconut fruit (CF). It was then blend with wheat flour (WF) into coconut wheat composite flour (CWCF) to produce cake. The CF and CWCF were subjected to proximate composition and functional properties analyses. Also, the physical properties, proximate composition and the sensory attributes of the cakes produced from CF and CWCF were determined.

Results: The moisture content of CF and CWCF ranged from 4.5 to 9.04 g/100 g, the ash content of CF and CWCF ranged from 4.10 to 6.41 g/100 g and the dietary fiber content of CF was 11.16 g/100 g. CWCF exhibited a higher (87.1± 0.6) water absorption capacity and packed bulk density (0.79 ± 0.3 g/ mL). In this study, the cake volumes increased significantly (P < 0.05) in wheat flour (WF) as compared to CWCF and CF. The specific cake volume observed ranged from 1.48 to 2.01 mL/g. The blend of 50% coconut and 50% wheat flour increased significantly (P < 0.05) the moisture content of the CWCF cakes. The total carbohydrate content of the cakes varied from 20.40 ± 0.02 g/ 100 g to 63.05±0.14 g/ 100 g. Fat, ash and crude fiber and minerals (Ca, K, P Zn, Mg and Fe) increased in CWCF cakes. The sensory analysis conducted showed that there was a significant difference (P < 0.05) between CF cakes, WF cakes and CWCF cakes in the sensory qualities of appearance, texture, flavour and overall acceptability. In terms of appearance, the panelists scored coconut cake highest, but was significantly different (P < 0.05) from coconut wheat cake and wheat one. The least liked sample in terms of texture was wheat one.

Conclusion: The present study underscored the potential application of coconut flour in the production of cake and possibly other bakery products.

Open Access Original Research Article

Heavy Metals Health Risk Assessment through Consumption of Baobab Leaf Cultivated in Katsina State, North West Nigeria

A. I. Yaradua, A. J. Alhassan, A. Nasir, K. I. Matazu, A. Usman, A. Idi, I. U. Muhammad, L. A. Saulawa, M. A. Dangambo

Asian Food Science Journal, Page 1-11
DOI: 10.9734/afsj/2019/v13i130096

Vegetables play important roles in human nutrition and health. They can also contain some undesirable components that can be harmful, e.g.  Pesticides and heavy metals. The objectives of the study were mainly to detect the presence of heavy metals (Cr, Cd, Fe, Ni, Mn, Pb and Zn) in sampled Baobab leaf in Katsina state Nigeria and assessed the human health risks associated with the consumption of the Baobab leaves. The content of these metals was assayed by the AAS method. The health risk to the local inhabitants was evaluated by estimating daily heavy metal intake and computing the Incremental Lifetime Cancer Risk (ILCR) and the Target Hazard Quotient (THQ) for cancer and non-cancer risks. The results were compared with the safety standards established by the WHO/FAO and USEPA. With the exception of the heavy metal Pb (0.526-0.981) the mean concentration (mg/kg) range values of Cr (0.116-0.352), Cd (0.041-0.054), Fe (1.016-1.951) and Zn (0.940-1.229) in the samples were generally lower than the USEPA, WHO/FAO maximum permissive limits. The risk level of Target Hazard Quotient (THQ < 1) was observed for all the evaluated heavy metals for both adults and children. The THQ for the samples was in the decreasing order Zn>Fe>Pb>Cr>Cd, for all the baobab leaf samples respectively. All the studied samples showed the risk level (HI < 1). ILCR for Cd violated the threshold risk limit (>10−4) and ILCR for Pb reached the moderate risk limit (>10−3) for cancer in all the studied samples in adults, While in children ILCR for Pb in samples from Dabai and Daura have reached the moderate risk limit (>10−3), while the ILCR for Pb in rest of the samples and ILCR for Cd of all the samples are beyond the moderate risk level (>10−2). The consumption of the Baobab leaf sample may contribute to the population cancer burden.

Open Access Original Research Article

Control of Aflatoxin Production in Cassava Produced by Dry Fermentation in North Kivu, Democratic Republic of Congo

Masika Yalala, L. Tshilenge-Lukanda, D. L. Yandju, A. Kalonji-Mbuyi

Asian Food Science Journal, Page 1-7
DOI: 10.9734/afsj/2019/v13i130097

Traditionally, cassava (Manihot esculenta Crantz) is transformed by fermentation in water (retting) or in the open air (dry fermentation) in the DRC. In the east of the country (North Kivu), dry fermentation is the main technique for processing cassava for its detoxification and conservation. The Congolese farmers ferment the cassava to the open air using a preselected microferment contained in the scrapings of the fermented cassava previously called "MUSIYIRO". These fermentations are spontaneously directed by the microorganisms of the uncontrolled autochthonous flora. Unfortunately, toxinogenic molds are often more active in the fermentation process during which they also produce aflatoxins. This study was undertaken to help prevent the production of aflatoxins in cassava during this process. To do this, we substituted the traditional ferment with a strain of Rhizopus oryzae used as starter (microferment). Six successive replications, in controlled fermentation and uncontrolled fermentation, in a peasant environment (Beni, North Kivu) and fermentation directed by the strain of R. oryzae were carried out. Aflatoxins were then dosed in both groups of cassava flours. The results of the assay revealed an absence of aflatoxins in cassava fermented by scrapings from fermentation led by R. oryzea, while the non-directed fermentation controls were all contaminated with aflatoxins. These results show that it is possible to prevent the production of aflatoxins in cassava during fermentation when an aflatoxin-inhibiting microbial biomass is used which can progressively invade and colonize the fermentation site and thereby control the fermentation activities of cassava.