Optimization of pectinase production by Aspergillus niger using central composite design

Pectinases are a group of enzymes that catalyze the breakdown of pectin. Pectinase producing Aspergillus niger was obtained from a five-day old Eba (Cassava flakes). Response surface methodology was used for optimizing the process of the pectinase produced. Four independent variables which are, temperature, pH, substrate concentration and time of Heating at  70oC were used to optimize the significant correlation between the effects of the variables on pectinase production. A second-order polynomial was fitted to data and validated by ANOVA. The results revealed maximum pectinase production at pH 6.0, 50oC Temperature, 0.02% substrate concentration and the enzyme lost all its activity within 7 min of heating at 70oC. The study revealed that optimization of pectinase through RSM could improve the enzymatic characteristics and yield of the enzyme. The models used were highly significant with a correlation coefficient (R2) of 0.901Keywords: Pectinase; Aspergillus niger; Response Surface Methodology; Central Composite Desig

Interpretation of Geoelectric Pseudo-Section of a Profile Across a Functional Borehole Located in-between Two Non-Functional Dug-Wells

Electrical resistivity imaging survey was carried at Agban, Kaura Area of Kaduna State Nigeria. A profile of 500m length was deliberately selected to cut across a functional borehole located averagely 100m in-between two non-functional dug-wells. Ten (10) VES Points were sounded along the profile in the N-S direction. Terrameter SAS300 was the instrument used. The tomogram of the profile shows that the area is underlain by four layers; the first layer is sandy clay with resistivity range of 200-500Ωm. This is taken as the Overburden. The second layer is the weathered basement which constitutes of Sandy soil and water. This is taken to be the aquifer which varies along the profile. The third layer comprise of coarse grain sand which is the fractured basement of resistivity range of 1000-2000Ωm. The fourth layer of resistivity greater than 2000Ωm is the fresh basement. The image also shows a U-shaped fracture zone within the subsurface, the borehole was drilled through this fracture which contains water. This fracture causes water to migrate from the locations of the wells and accumulate at the borehole site. This research has gone a long way to establish the facts that since the dug wells are shallow; they failed at the end of the dry season when groundwater levels fall. It is a common knowledge that little specialist equipment is used for the construction of a well even though it is difficult to construct hand dug wells in hard rock. On the basis of the results of this study, we therefore recommend that thorough geophysical survey should always be carried out in the basement complex before constructing dug wells for them to be sustainable. Keywords: Resistivity1, Kaura2, Wel

Geophysical Investigation of the Causes of Borehole Failure in the Crystaline Basement Complex: A Case Study of Kaura Area of Kaduna State, Nigeria

Vertical Electrical Soundings (VES) using Schlumberger array were carried out at different points along five (5) profiles. This research investigates the causes of massive borehole failure at Kaura area of Kaduna state using the resistivity tomography techniques. Terrameter SAS300 is the instruments used to acquire the data. A total of 19 boreholes are functioning, while 31 boreholes are non-functioning within the area. The investigation has portrayed the possible factors which are most probably causative to borehole failures in the area which involves the design and construction, groundwater potential/hydrogeological factors and operational and maintenance factors. It was found out that it is possible for one factor to lead to the other. For example, a borehole poorly designed, constructed and completed could result in sand/clay pumping and eventually affect the rubber seals in the hand pumps or the impellers in the case of submersible pumps. The boreholes tap the weathered and fractured basement aquifers of the area with yields ranging from 2litre/min to 20litre/min. However, yields from Sandy soil aquifers were found to be extensive. The survey shows that boreholes with initial recorded yield less than 10litre/min have failed over time. The survey reveals that the areas where wells and boreholes are drilled through sandy soil and fracture zones have sustainable aquifers for groundwater exploitation, while boreholes that are constructed through clayey formation usually fail. Keywords: Resistivity1, Kaura2, Borehole failur

Geophysical Investigation of the Causes of Borehole Failure in the Crystaline Basement Complex: A Case Study of Kaura Area of Kaduna State, Nigeria

Vertical Electrical Soundings (VES) using Schlumberger array were carried out at different points along five (5) profiles. This research investigates the causes of massive borehole failure at Kaura area of Kaduna state using the resistivity tomography techniques. Terrameter SAS300 is the instruments used to acquire the data. A total of 19 boreholes are functioning, while 31 boreholes are non-functioning within the area. The investigation has portrayed the possible factors which are most probably causative to borehole failures in the area which involves the design and construction, groundwater potential/hydrogeological factors and operational and maintenance factors. It was found out that it is possible for one factor to lead to the other. For example, a borehole poorly designed, constructed and completed could result in sand/clay pumping and eventually affect the rubber seals in the hand pumps or the impellers in the case of submersible pumps. The boreholes tap the weathered and fractured basement aquifers of the area with yields ranging from 2litre/min to 20litre/min. However, yields from Sandy soil aquifers were found to be extensive. The survey shows that boreholes with initial recorded yield less than 10litre/min have failed over time. The survey reveals that the areas where wells and boreholes are drilled through sandy soil and fracture zones have sustainable aquifers for groundwater exploitation, while boreholes that are constructed through clayey formation usually fail. Keywords: Resistivity1, Kaura2, Borehole failur

Chemical compositions of Casuarina equisetifolia L., Eucalyptus toreliana L. and Ficus elastica Roxb. ex Hornem cultivated in Nigeria

AbstractEssential oils were obtained by separate hydrodistillation of three different plants cultivated in Nigeria and analysed comprehensively for their constituents by means of gas chromatography (GC) and gas chromatography-mass spectrometry (GC–MS). The leaf essential oil of Casuarina equisetifolia L. (Casuarinaceae) comprised mainly of pentadecanal (32.0%) and 1,8-cineole (13.1%), with significant amounts of apiole (7.2%), α-phellandrene (7.0%) and α-terpinene (6.9%), while the fruit oil was dominated by caryophyllene-oxide (11.7%), trans-linalool oxide (11.5%), 1,8-cineole (9.7%), α-terpineol (8.8%) and α-pinene (8.5%). On the other hand, 1,8-cineole (39.4%) and α-terpinyl acetate (10.7%) occurred in large quantities in the essential oils of the leaf of Eucalyptus toreliana L. (Myrtaceae). The oil also features high levels of sabinene (5.9%), caryophyllene-oxide (4.7%) and α-pinene (4.2%). The main compounds identified in the leaf oil of Ficus elastica Roxb. ex Hornem. (Moraceae) were 6,10,14-trimethyl-2-pentadecanone (25.9%), geranyl acetone (9.9%), heneicosene (8.4%) and 1,8-cineole (8.2%)

Effect of variation in temperature and relative humidity on the reproductive performance of grasscutters held in captivity

This study investigated the reproductive performance of grasscutter through oestrus, mating, parturition, abortion and litter size in establishing the success of this performance during the rainy season and dry season. Effects of the atmospheric temperature and relative humidity on the reproductive performance of grasscutter in captivity were duly observed. Twenty female grasscutters were used with ten males for mating and were subsequently individually caged to determine the outcome of male-female contact (i.e. mating, conception and parturition). The signs of mating were detected by observing the marks of climbing at the back of the female grasscutter (doe),observing the changes in the perineum of the female before and after mating, monitoring the changes in weight gained post-mating and presence of fetuses by abdominal palpation. Parturition was detected by monitoring the expectant mothers with successful mating signs and distended abdomens. Keywords: Grasscutter, reproductive performance, reproduction, parturition, mating

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Chemical composition of Casuarina equisetifolia L., Eucalyptus toreliana L. and Ficus elastica Roxb. ex Hornem cultivated in Nigeria

Essential oils were obtained by separate hydrodistillation of three different plants cultivated in Nigeria and analysed comprehensively for their constituents by means of gas chromatography (GC) and gas chromatography-mass spectrometry (GC–MS). The leaf essential oil of Casuarina equisetifolia L. (Casuarinaceae) comprised mainly of pentadecanal (32.0%) and 1,8-cineole (13.1%), with significant amounts of apiole (7.2%), α-phellandrene (7.0%) and α-terpinene (6.9%), while the fruit oil was dominated by caryophyllene-oxide (11.7%), trans-linalool oxide (11.5%), 1,8-cineole (9.7%), α-terpineol (8.8%) and α-pinene (8.5%). On the other hand, 1,8-cineole (39.4%) and α-terpinyl acetate (10.7%) occurred in large quantities in the essential oils of the leaf of Eucalyptus toreliana L. (Myrtaceae). The oil also features high levels of sabinene (5.9%), caryophyllene oxide (4.7%) and α-pinene (4.2%). The main compounds identified in the leaf oil of Ficus elastica Roxb. ex Hornem. (Moraceae) were 6,10,14-trimethyl-2-pentadecanone (25.9%), geranyl acetone (9.9%), heneicosene (8.4%) and 1,8-cineole (8.2%)