Nigerian Stored Products Research Institute Research Articles

Mathematical modelling of the drying characteristics and economic analysis of Hake fish using Smoking Kiln

Aim: This study aims to provide a detailed assessment on the mathematical modelling of the drying characteristics of Hake Fish using smoking kiln. This will help in the prediction and simulation of the ideal drying circumstances that will preserve quality, and extend the product’s shelf life. Methods: Frozen Hake Fish (15 kg) was procured and transported for further processing at the Nigerian Stored Products Research Institute, Ibadan. Thereafter, Hake Fish was weighed, sorted, washed, brined, and smoke-dried. Triplicate samples were marked out and moisture loss was monitored at intervals during the drying process at temperature ranging from 85 – 115 \\degc, thus, experimental data was generated. The drying data were then fitted into six mathematical models and results were compared using the coefficient of determination (R2) and root mean square error (RMSE), hence, the best model was selected. The parameters of the models were evaluated using non-linear regression analysis. The economic viability of smoke-drying Hake fish was assessed with the application of standard economic assessment tools. Results: The initial and final moisture content of Hake Fish was 233.351 and 4.93% db, respectively. The drying period to achieve the safe moisture content was seven hours. All through the process of drying, no constant drying rate period was discovered as the drying rate curve exhibited a falling rate with drying rate (0.0117±0.0060 kg/h) increasing with increasing temperature. Midilli model gave the best performance in predicting the drying characteristics of Hake Fish using Smoking Kiln. The economic assessment suggests that there is a high profitability for fish processing using improved processing methods. Conclusion: The drying kinetics of Hake Fish can be effectively explained using smoking kiln. The smoking kiln is economically viable. Also, the use of smoking kiln will produce high quality dried product.

Microbial and Fungal Contamination of Different Dried Cocoyam Flakes during Storage

Background: Contamination of food by microorganisms from the processing to the consumption stage has become a major health concern in this era, where a better approach for the elongation of food shelf life is explored. This study aims to evaluate the microbial and fungal contamination of different dried cocoyam flakes during storage.
 Methods: The cocoyam (Colocasia esculenta) samples were properly cooked, peeled, sliced into thin shapes, and dried to constant weights. The drying methods used were sun, hot-air oven, and Nigerian Stored Products Research Institute (NSPRI) multi-crop dryer; samples were divided into three groups A, B, and C, respectively, and the dried samples were stored for three months. Moisture Content (MC) was conducted using the standard method. Colonial morphology, Gram staining, and biochemical test were used to identify and characterize microorganisms. Statistical analyses were performed using SPSS 20.0.
 Results: There was a significant increase in the MC of all the samples after the storage duration. The sun-dried sample had the highest MC (13.60%) while the oven-dried sample had the lowest MC (10.82%). The sun-dried samples had the highest viable bacteria count (7.2×105 Colony Forming Unit (CFU)/g) and the oven-dried sample had the lowest count (5.1×105 CFU/g). The four bacterial isolates identified were Bacillus subtilis, Pseudomonas aeruginosa, Micrococcus luteus, and Staphylococcus aureus. The heterotrophic fungal number was the highest (0.5×103 CFU/g) regarding sun-dried samples, whereas the samples dried with NSPRI multi-crop dryer and oven-dried samples had the same value (0.3×103 CFU/g). Aspergillus flavus, A. niger, Rhizopus, Penicillium, and Mucor were isolated from the samples. Rhyzopertha dominica was identified in sun-dried samples.
 Conclusion: The increase of MC and the nature of the storage material may have contributed to high bacterial and fungal counts of stored dried cocoyam flakes, especially sun-dried ones, thereby exposing consumers to potential health risks.

STUDY OF QUALITY CHANGES IN Clarias gariepinus (BURCHELL 1822) STORED IN MODIFIED ICE FISH BOXTM

Fish is a very perishable commodity that deteriorates after harvest without proper handling, transportation, and storage. Nigerian Stored Products Research Institute Ice Fish BoxTM has been improved to have a greater capacity for more storage of fish as well as the development of a trolley to ease movement and a change in position of the drain spot increasing the performance of the drainage system. Thirty (30) kilograms of freshly harvested Clarias gariepinus and thirty (30) kilograms of ice were layered alternately at a ratio 1:1 in the modified box for pH, total volatile base nitrogen (TVBN), trimethylamine (TMA), total viable count (TVC) and freshness evaluation using Quality Index (QI) at a sampling period of 24 hours and sensory evaluation of processed fish using Likert scale. C. gariepinus, stored for a maximum of 48 hours with pH between 6.70 and 7.17, TVBN, 5.52 - 8.25 mg/100 g, TMA, 0.84- 2.33 mg/100g, TVC, 1.0x102 - 3.8x103 cfu/g, QI, 7 and sensory evaluations were above 4. The quality indices were within acceptable limits. It is anticipated that this would lower the amount of loss that occurs after harvest thus boosting revenues in the fish value chain and improving food and nutritional security

Performance evaluation of NSPRI parabolic solar dryer for drying of bell pepper

Parabolic solar dryer developed by Nigerian Stored Products Research Institute was used to dry bell pepper. The drying rate, color changes and drying kinetics using some empirical modelling equations were determined. Open sun drying method was used as a control. Drying rate (2.11 kg/day) of the parabolic solar dryer was significantly higher than that of the sun drying (1.92 kg/day). Bell peppers dried under parabolic dryer retained their color better than those peppers under sun drying. Page model is the most suitable model to describe the drying kinetics of the bell pepper under solar drying. The drying constant k (0.607) of the parabolic dryer is significantly higher than that of the sun drying (0.321) indicating higher mass transfer in the parabolic solar dryer.

Evaluation of improved vegetable baskets for storage of Amaranthus viridis (green amanranths) and Telfaria occidentalis H. (fluted pumpkin leaves)

The new vegetable baskets (VBs) were tested for effectiveness in the storage of fresh leafy vegetables. Freshly harvested Amaranthus viridis and Telfaria occidentalis H. were obtained from farms and transported to Nigerian Stored Products Research Institute (NSPRI), Ilorin, where they were sorted, washed and air-dried. Four different models; namely the pyramidal big basket (PBB), frustum big basket (FBB), polyethene lined small basket (PSB) and foam-lined small basket (FSB) were used while the control sample was left open in a plastic crate on the shelf. The set-up was monitored on 24 hourly bases for wetting, physiological weight loss (PWL) and physical observations until decay was observed. Sensory attributes and physicochemical properties were evaluated before and after storage using standard methods. Results obtained indicated that fresh green amaranths and fluted pumpkin leaves were rated higher in colour and appearance than the stored leaves. The PWL ranged from 16.18–100% and 18.42–99.62% for A. viridis and T. occidentalis H. respectively. The proximate composition analysis conducted showed that moisture, protein, fibre and ash contents ranged between 66.45-89.32, 20.32-44.36, 12.18-41.17, 5.48-15.40% respectively for A. viridis and 65.34-79.94, 12.57-26.09, 19.37-44.12 and 3.31-11.29% respectively for T. occidentalis. Conclusively, PBB, FSB and PSB conserved more weight, chlorophyll and vitamin C contents respectively in A. viridis; while FSB and PSB conserved more weight and chlorophyll respectively in T. occidentalis H. Thus, the three models; PBB, PSB and FSB were most effective in the storage of A. viridis and T. occidentalis H.

Effects of NSPRI wall-in-wall evaporative coolant on physical properties of stored tomato

Nigerian Stored Products Research Institute developed a wall-in-wall evaporative cooling system for the storage of fresh fruits and vegetables. This is an effort in mitigating post-harvest loss of fruits and vegetables. The effect of the cooling system on the physical properties of tomatoes was investigated using ambient shelf storage as a control. Weight loss, firmness loss and colour changes of tomatoes were the major physical properties studied. Tomatoes were stored for 24 days. There was significantly higher loss in weight of tomatoes stored in ambient (68%) than those of the evaporative coolant (32%). There was significant higher loss in firmness of the tomato stored in ambient (95%) those in evaporative cooling system (58%). Tomatoes stored in evaporative cooling system retained better color while those under ambient became darkened at the end of the storage period.

Nigeria Stored Products Research Institute Multipronged Approach to Disseminationof Improved Postharvest Technologies in Nigeria

Modern Concepts & Developments in Agronomy Nigeria Stored Products Research Institute Multipronged Approach to Disseminationof Improved Postharvest Technologies in Nigeria Adegbola JA1*, Ogunremi O4, Owojaiye OB2, Achime KC3, Aina OB4, Akinola-Soji B3 and Lijoka KO4 1Chief Research Officer, Nigeria 2Principal Research Officer, Nigeria 3Senior Research Officer, Nigeria 4Research Officer I, Nigeria *Corresponding author: Adegbola JA, Chief Research Officer, Nigerian Stored Products Research Institute, Ilorin, Nigeria Submission: September 06, 2022;Published: September 19, 2022 DOI: 10.31031/MCDA.2022.11.000767 ISSN 2637-7659Volume11 Issue 4

Willingness to use ice-fish box by fresh fish value-chain actors in Lagos State, Nigeria

A fish preservation technology was developed in the year 2016 by Nigerian Stored Products Research Institute, (NSPRI) in a well-insulated container known as “NSPRI Ice-Fish Box” (NSPRI-IFB). The technology was disseminated to fresh fish value-chain actors (farmers, marketers, processors and transporters) in selected coastal local government areas of Lagos State namely Lagos Mainland, Epe, Badagry and Ikorodu which housed Asejere, Epe, Badagry and Ijede fish markets respectively in 2019. The study was conducted in these markets to ascertain the awareness status and determine the willingness of these actors to use NSPRI-IFB. Data were randomly collected from 110 respondents selected through a simple random sampling procedure using questionnaire and analysed using descriptive statistics and Chi-square statistical tool. Excellent numbers of actors (81.82%) are well aware of NSPRI-IFB while 27.27% of them declare they are not aware. Results further shows that actors are very willing to use NSPRI-IFB for fresh fish preservation (x̄ = 3.87) and transportation (x̄ = 3.81). However, they are not at all willing to use the technology for fish processing (x̄ = 1.67) and curing (x̄ = 1.73). Chi-square analysis reveals significant associations (p≤0.05) between willingness to use NSPRI-IFB and actors’ age and level of education. Conclusively, value-chain actors are well aware and are willing to use the technology. Fresh fish postharvest loss reduction policy should be directed towards mass adoption of NSPRI-IFB.

Willingness To Use Ice-Fish Box by Fresh Fish Value-Chain Actors in Lagos State, Nigeria

A fish preservation technology was developed in the year 2016 by Nigerian Stored Products Research Institute, (NSPRI) in a well-insulated container known as “NSPRI Ice-Fish Box” (NSPRI-IFB). The technology was disseminated to fresh fish value-chain actors (farmers, marketers, processors and transporters) in selected coastal local government areas of Lagos State namely Lagos Mainland, Epe, Badagry and Ikorodu which housed Asejere, Epe, Badagry and Ijede fish markets respectively in 2019. The study was conducted in these markets to ascertain the awareness status and determine the willingness of these actors to use NSPRI-IFB. Data were randomly collected from 110 respondents selected through a simple random sampling procedure using questionnaire and analysed using descriptive statistics and Chi-square statistical tool. Excellent numbers of actors (81.82%) are well aware of NSPRI-IFB while 27.27% of them declare they are not aware. Results further shows that actors are very willing to use NSPRI-IFB for fresh fish preservation (x̅ = 3.87) and transportation (x̅ = 3.81). However, they are not at all willing to use the technology for fish processing ( x̅= 1.67) and curing ( x̅= 1.73). Chi-square analysis reveals significant associations (p≤0.05) between willingness to use NSPRI-IFB and actors’ age and level of education. Conclusively, value-chain actors are well aware and are willing to use the technology. Fresh fish postharvest loss reduction policy should be directed towards mass adoption of NSPRI-IFB.

Quality Assurance, Safety and Acceptability of Odourless Fufu Flour Produced from White and Yellow-Flesh Cassava using NSPRI-Technology

Fufu is one of the major fermented cassava food product widely consumed in Nigeria. Due to several unhygienic methods of preparation and objectionable odour, this study was carried out to investigate the nutritional, cyanide, rheological and microbial properties of odourless fufu flours produced from white and yellow flesh cassava using Nigerian Stored Products Research Institute (NSPRI) Technology and sensory properties of smooth dough prepared from the reconstituted flours. The results showed that both white and yellow odourless fufu has safe moisture content (4.34 to 7.21%). It was also observed that white and yellow odourless fufu had an improved pasting properties with pasting temperature and viscosity of (71.850C to 75.230C and 3088cp - 3797cP), The Cyanide content and microbial analysis of both flours were within the safe range with no coliform bacterial present. The sensory evaluation from panelists showed that white odourless fufu had a better overall acceptability despite yellow flesh having higher ascorbic acid and T. carotenoid content. From the study, it can be concluded that the cyanide content, microbial load of the processed flour samples using NSPRI technology were at a safe level. Which makes it safe for consumption and the level of moisture content of the flours would make the flours suitable for long term storage.

Influence of processing methods on the quality attributes of bio-fortified sweet potato products

Bio-fortified sweet potato (BSP) is one of the crops that can be used to address the problems of vitamin A deficiency in the Sub-Saharan Africa but it’s currently being underutilized. This study seeks to evaluate the effects of different heat processing methods on the quality of products made from BSP in order to increase its utilization. Freshly harvested tubers were purchased from a Research Farm in Federal University of Agriculture, Abeokuta (FUNAAB), Nigeria and brought to the Processing Centre, Nigerian Stored Products Research Institute (NSPRI), Ilorin. The sample was taken through some standard pre-processing operations of sorting, peeling, washing, slicing (2.11 mm), and deep frying (3 minutes) while some portions were boiled immediately after sorting with or without skin for 10–15 minutes. Each treated sample was analysed for sensory, proximate, vitamins and mineral compositions following standard methods. Results showed that fried sample had highest acceptability for aroma (7.25) and crispiness (7.00) while sample boiled without skin (15 min) was rated with least scores in colour (5.30), appearance (5.40), texture (4.95), crispiness (4.65) and overall acceptability (5.70). Protein, vitamin C, phenolics, flavonoids and reducing sugar contents were 6.53–18.52%, 10.89–76.69 mg/100 g, 0.57–3.15 mg/L, 94.64–383.91 mg/L and 43.05–237.12 g/100 g respectively while some minerals such as Na, K and Zn ranged from 8.42–17.45, 5.12–9.30 and 0.03–0.09 mg/L respectively. Different heat processing at different durations affected the sensory attributes, nutritional and mineral compositions of BSP.
 Key words: Post-harvest, food security, potato, heat treatment, quality

Increasing the shelf-life and quality of matured scotch bonnet (Ata rodo) and tomato using chitosan coating

Loss in quantity and quality of several perishable crops occur between harvest and handling process to the final consumer. In tomatoes and scotch bonnet, the quality loss occurs majorly due to over-ripening, mechanical damage, fungal infection and decay. Extending the shelf life and storability of these perishable crops has been of major concern to researchers. Hence, this study was carried out to determine the protective effect of chitosan coating on post-harvest qualities of matured scotch bonnet and tomato. Freshly harvested scotch bonnets and tomatoes from a field plot at Nigerian Stored Products Research Institute, Ibadan were sorted on the basis of color, size and absence of external injuries. The selected crops were randomly divided into two groups (group with chitosan and without chitosan). Chitosan synthesized from Chemistry Department in Nigerian Stored Products Research Institute, Ibadan was used to coat the scotch bonnets and tomatoes crops in group 1 while group 2 served as the control. The coated scotch bonnets and tomatoes where kept at room temperature and monitored on daily basis for seven days for scotch bonnet and twenty days for tomato. Chitosan coating markedly reduced the weight loss, fungal infection, shrinking and decay, improving the firmness and titratable acidity in group coated with chitosan. It can be concluded that chitosan coating delays senescence and fungal infection in scotch bonnet and tomato most likely due to its ability to alleviate water stress and its anti-fungal activities.

Commercial utilization of inert atmosphere silo for maize storage

Inert atmosphere silo (IAS) has been advocated by Nigerian Stored Products Research Institute (NSPRI) as a sustainable alternative to the use of conventional silos and synthetic chemicals for grains storage in tropical climates. A battery of two units of 250 tonnes IAS installed at the commercial farm of Landmark University Omu-Aran by NSPRI was evaluated for maize storage. Quality parameters such as proximate compositions and microbial loads were determined and their respective results subjected to T-Test statistical analysis. The results of the analysis showed a slight increase in moisture content from 10.57 % to 10.66 % (db) after 6 months of storage. During the storage period, insect infestation was completely suppressed and quality of the grain was maintained, as there was no significant difference at (P≤ 0.05) in the proximate compositions of the initial and final samples. There was significant difference (P≤0.05) in bacteria loads and fungi counts of the initial and final samples. Reduction in microbial loads was experienced and the values obtained were within acceptable limits (104 Cfu/g) recommended for cereals. The germinability of the maize was maintained at 96 % after 6 months; thus indicating effectiveness of the technology for commercial storage of maize seed.

Characteristics and Antibiogram Studies of Bacteria Associated with Vegetables Stored In Raffia Baskets in Nigeria

Raffia baskets are used in rural communities to preserve fresh vegetables for a given period of time. This method of storage is aimed at extending the shelf life of the vegetables until they are used. Thus, this study was aimed at determining the microbial succession during storage and susceptibility pattern of bacterial isolates from stored leafy vegetables to various antibiotics. Five (5) leafy vegetables namely, Bitter leaf (Vernomia anydalira), Water leaf (Talinum triangulare), Fluted pumpkin leaf, (Telfairia occidentalis), Okazi leaf (Gnetum africana) and Scent leaf (Ocimum gratissimum) were obtained from the Nigerian Stored Products Research Institute (NSPRI) farm, Port Harcourt. These vegetables were stored in a raffia basket for fourteen (14) days while another set of the vegetables were left in the open air as control. This set up was monitored for changes to occur. Standard microbiological techniques were employed for the various analyses of the vegetable samples. Both cultural and molecular characterizations of the isolates were done. The disc diffusion method was used in determining the susceptibility pattern of the bacterial isolates. The results of the predominant microorganisms identified were of the genus; Bacillus, Pseudomonas, Enterococcus, Enterobacter, Bordetella, Staphylococcus, Myroides, Escherichia, Serratia, Micrococcus and Acetobacter. Also, Bacillus species occurred in all the vegetables while Enterococcus faecalis, Acetobacter orientalis, Bordetella pertussis, Myroides xuanwuensis and Bacillus flexus were isolated on the third day of storage from the vegetables. The total heterotrophic bacterial counts ranged from 1.8 x106 cfu/g to 1.25 x107 cfu/g (bitter leaf), 9x105 cfu/g to 9.0 x106 cfu/g (Scent leaf), 7 x105 cfu/g to 1.88 x107 cfu/g (Okazi), 3.2x106 cfu/g to 1.05x107 cfu/g (Fluted pumpkin leaf) and 8.4 x106 cfu/g to 2.04 x107 cfu/g (water leaf). Antibiogram of bacterial isolates revealed that they were resistant to Augmentin and Ceftazidime according to Clinical Laboratory Standard Institute schemes. Combination of the antibiotics showed that most of the isolates were 100% susceptible to ciprofloxacin + erythromycin, and ciprofloxacin + ceftriaxone. The study revealed that for all the vegetables, those stored in the basket lasted longer and were fresher compared to those kept in the open space. This study revealed that the raffia baskets are suitable for storage and preservation of leafy vegetables, but microbial succession occurred as a result of increase in the period of storage leading to the proliferation of microorganisms. This could be from aerosols or by chance inoculation, through handling or materials used or other microorganisms which are inherent in the vegetables because of their contact with the soil or water used in the washing of the leaves.

Microbiological Quality and Antibiotic Susceptibility Profile of Microorganisms Associated with Stored Vegetables in Port Harcourt

Aim: Vegetables are good sources of nutrients such as minerals, oil, vitamins and carbohydrates and are used in preparing different delicacies such as soups and salads. This study was aimed at investigating the microbiological quality and antibiotic resistance pattern of microorganisms associated with stored vegetables in raffia baskets.
 Methodology: The vegetables were obtained from the Nigerian Stored Products Research institute (NSPRI) farm in Port Harcourt. Ten grams (10 g) each of fresh vegetables were homogenized differently in 90ml of sterile diluent. Aliquot (0.1 ml) of 10-3 and 10-5 dilutions of each vegetable sample was plated on nutrient agar plates and incubated at 37ºC for 24hours. Identified isolates were standardized using the 0.5 McFarland standard. This was done by transferring colonies of the test isolates into sterile 4 mL normal saline and comparing the turbidity of the isolate in the test tubes with the already prepared 0.5 McFarland. The disc diffusion method was used in determining the susceptibility pattern of the microorganisms against the antibiotics. In this method, the standardized inoculums were seeded aseptically on freshly prepared Mueller Hinton agar plates. Whatman discs which have been impregnated with different concentrations of the antibiotics were placed on the seeded plates and incubated at 37ºC for 18-24 hours. 
 Results: Zones of clearance or inhibition on plates were recorded. The genera Bacillus, Pseudomonas, Enterococcus, Enterobacter, Bordetella, Staphylococcus, Myroides, Escherichia, Serratia, Micrococcus and Acetobacter were identified as predominant microbes from the vegetables.
 Conclusion: Despite the high level of resistance to the antibiotics, Ciprofloxacin and Ofloxacin were the most effective and preferred drugs of choice for treatment of infections arising from the consumption of these vegetables. Adequate heating and blanching of vegetables is required at all times to prevent food poisoning.

Three and half decades of research on controlled atmosphere storage of grains under nitrogen and recent utilization of the technology in Nigeria

A major breakthrough of Nigerian Stored Products Research Institute (NSPRI) is in the development of Inert Atmosphere Metal Silo (IAMS) in bulk grain storage for suitability of the climate, adoption and utilization in Nigeria. This technology uses nitrogen gas to achieve a controlled atmosphere (N2-CA) or environment for the control of stored products pests infestation and damage. Achieved 100% mortality of all life adults and immature stages of stored products insect pests; inhibited mould growth, maintained biochemical composition of stored grain and germinability (85% -91%) recorded at 12 months of storage. The system has been used to effectively store white maize, groundnut, Ife brown cowpea, wheat, paddy rice and yellow sorghum for periods of 12 – 48 months. The only system that has ability to store cowpea which cannot be stored in conventional silos. Research activities commenced from laboratory trials to pilot scale and later to medium and commercial levels. Shading the IAMS top against direct sun effect with palm fronds or hood for insulation prevented moisture migration and condensation, and maintained temperature below 30 oC in stored grain. A return per unit on investment of 0.44 was recorded when utilized for storage of wheat for a period of 48 months. IAMS has economic advantages over conventional silos which require frequency of pesticides application, turning of grains to prevent caking, food poisoning and high cost of labour. The recent utilization of this technology is due to increased awareness and demands for availability of grains for food safety, quality and nutrition. IAMS is being taken up by some entrepreneurs, marketers and Landmark University, Omu-Aru, Kwara state for grain storage in Nigeria. This technology is available for use at smallholder, medium, commercial and strategic grain reserve levels. Three and half decades of application of IAMS technology in grain storage in Nigeria is discussed.

Comparative study of the Nutritional, Phytochemical and Mineral Compositions of the nuts of Tropical Almond (<i>Terminalia catappa</i>) and Sweet Almond (<i>Prunus amygdalus</i>)

The study was conducted to compare the nutritional, phytochemical and mineral compositions of Tropical almond with Sweet almond. Sample of Terminalia catappa nuts were collected within the premises of Nigerian Stored Products Research Institute (NSPRI), Ilorin, Nigeria while Prunus amygdalus was purchased from Shoprite Palms Mall Ilorin, Nigeria. Proximate, phytochemical and mineral analyses were carried out using standard procedures. Results showed that T. catappa was significantly (p 0.05) was recorded in their protein contents (33.00 and 32.89% respectively). P. amygdalus was significantly (p<0.05) high in phytochemicals such as tannin (748.49µg/g), phenols (1,781.50 µg/g), flavonoids (456.38 µg/g), saponin (158.70 µg/g) and alkaloids (240.11µg/g) while T. catappa was significantly (p<0.05) high in glycosides (220.27µg/g).The differences in phytochemicals might be due to the differences in drying and other processing methods. T. catappa can well compete with P. amygdalus if the value chain is improved upon by proper packaging and storage for commercial purposes. Keywords. Almond, nuts, nutrition, Ilorin, Nigeria

QUALITATIVE AND QUANTITATIVE PHYTOCHEMICAL EVALUATION AND MINERAL CONTENTS OF THE LEAF OF ANNONA MURICATA

QUALITATIVE AND QUANTITATIVE PHYTOCHEMICAL EVALUATION AND MINERAL CONTENTS OF THE LEAF OF ANNONA MURICATA Nwaehujor Idorenyin Ugochi*, Lawal Israel Oluwasanmi, Akande Samuel Adesayo Nigerian Stored Products Research Institute, P.M.B. 1489, Ilorin, Kwara State, Nigeria ABSTRACT In recent years, interest has increased in the utilization of therapeutic plants since herbal remedies have been publicized to be safe and without adverse side reaction as synthetic drugs. The goal of this research was to perform qualitative and quantitative phytochemical evaluation and also to examine the mineral contents of Annona muricata leaf collected in Ilorin, Kwara State, Nigeria. Annona muricata leaf was dried at room temperature. Cold extraction method was employed to obtained crude extracts with solvents of varying polarities. Hexane, ethyl acetate and ethanol were utilized. Mineral determination was carried out using Atomic Absorption Spectroscopy. Phytochemicals from the leaf extracts were; saponins, phenols, tannins, glycosides, steroids, terpenoids and alkaloids. All the samples showed high content of alkaloids and saponins. Mineral evaluation of the leaf showed that Calcium had highest concentration in the leaf, (6.7 mg/g) while Iron, Manganese, Copper and Zinc were also detected. Annona muricata leaf contain important phytochemicals, as such, the leaf is a potential source of new bioactive compounds. Due to the high concentration of Calcium in the leaf, the leaf can serve as herbal supplement for patient with high blood pressure. Keywords: Annona muricata, phytochemical, mineral, medicinal, extract Full Text Article

Effect of variations in growth parameters on cellulase activity of Trichoderma viride NSPR006 cultured on different wood-dusts

Aims: The biotechnology research into agro wastes has been driven by the need to screen organisms for hyperproduction of novel extracellular enzymes in which cellulase plays a significant role. Therefore, the aim of the study was to pre-screen selected fungal strains and optimize cultural conditions for cellulase production by Trichoderma viride NSPR006 cultured on pretreated sawdust as lignocellulosic substrate. Methodology and results: The selected fungal isolates namely Trichoderma viride NSPR006, Botrydiplodia NSPR007 and Acremonium butyri NSPR06B obtained from the culture collection of the Nigerian Stored Products Research Institute Ilorin, Kwara State, Nigeria were screened for the production of cellulase in mineral salt medium in which carboxymethylcellulose (CMC) had been incorporated as the sole carbon source. All the tested fungal isolates produced cellulase with differences in the amount of enzyme production. Of all the selected fungal isolates screened, Trichoderma viride NSPR006 was found to yield highest cellulase activity compared to the other isolates. Among tested carbon sources, Pachyslasma tessmani wood dust at 3% level proved to the best for cellulase production. Of the entire tested organic nitrogen sources, locust beans were observed to yield maximum cellulase activity (0.194 µmol/min/mL). The optimum temperature, incubation time and pH for maximum cellulase production were 28 °C, 72 h and 6.5, respectively. Conclusion, significance and impact of study: Outcome of this study shows the effectiveness of pre-treatment of wood dust as low cost system for hyper-production of cellulase for industrial application. Also, the work revealed the use of pretreated wood dust as substitute to commercial substrate known to be expensive in cellulase production.

Effect of NSPRI tin-in-pot compared with pot-in-pot evaporative cooler on the stored fruits

The suitability of the humidity chambers known as Evaporative Cooling System (ECS) developed by Nigerian Stored Products Research Institute as storage structures for mangoes were compared for nine days between June-July 2012. Ambient and ECS Temperature throughout the storage period ranges between 27?C- 31?C and 20?C-27?C respectively, while the corresponding relative humidity was 51%-58% and 70%-81% respectively. Colour change and Weight loss were observed as a physical change to determine effect of each selected ECS on the stored mangoes. There is significant range of ripening in tin-in-pot which led to early deterioration of the stored mangoes. Pot in-pot affects the freshness of the stored mangoes. The overall effectiveness of the tested ECS shows that tin-in-pot is better for the storage of mangoes since for five days, it retains the freshness of the stored mangoes but cannot be used for long due to its natural reaction with the stored fruits.