Xylanase production by Aspergillus niger ANL 301 using agro - wastes

Xylanase production by wild-type Aspergillus niger ANL301, newly isolated from wood-waste, was monitored at 24 h intervals for a period 168 h in media containing different carbon sources. The carbon sources were oat-spelt xylan (Fluka) and three agro-wastes (sawdust, sugarcane pulp and wheat bran). Highest xylanase activity of 6.47 units/mL was obtained at 96 h in media containing wheat bran as sole carbon source. Maximum activity value for the media containing sugarcane pulp was 0.95 units/mL obtained also at 96 h. Sawdust and oat spelt xylan gave the peak enzyme activities of 0.65 and 0.80 units/mL respectively at 120 h. High protein yield was obtained in media containing the agro-wastes, with wheat bran giving the highest value of 1.14 mg/mL at 96 h. The maximum specific xylanase activities were 3.86, 3.37, 5.69, and 9.36 units/ mg protein for sawdust, sugarcane pulp, wheat bran and oat spelt xylan, respectively. Out of the three agro-wastes used in this study, wheat bran holds greatest promise for low cost production of the xylanase enzyme

Agro-waste: a potential fermentation substrate for Penicillium chrysogenum

Common agro-wastes found in Lagos, Nigeria (cassava shavings, corncob, sawdust, and sugarcane pulp) were compared with glucose and lactose as fermentation substrates for Penicillium chrysogenum PCL501. Cassava shavings significantly (P<0.001) produced the highest amount of mycelia weight (0.43 ± 0.02 mg/ml) than all the other substrates. This was followed by corncob with peak mycelia weight of 0.33 ± 0.02 mg/ml. Peak mycelia weight of 0.27 ± 0.01 mg/ml was equally obtained with glucose and sugarcane pulp whereas lactose gave a slightly lower peak of 0.25 ± 0.01 mg/ml. Sawdust gave the least mycelia weight of 0.13 ± 0.01 mg/ml. Total sugar content of all the culture media steadily decreased as fungal growth progressed indicating that the organism utilized carbohydrates for growth and mycelia formation. Cultures containing cassava shavings and sawdust gave high protein peaks of 0.84 ± 0.05 and 0.65 ± 0.03 mg/ml respectively. Cultures containing corncob, glucose, lactose and sugarcane pulp yielded lower protein peaks of 0.37 ± 0.02, 0.30 ± 0.02, 0.24 ± 0.02 and 0.18 ± 0.01 mg/ml respectively. The results suggest that cassava shavings, corncob and sugarcane pulp could serve as cheap fermentation substrates for the growth of the fungus. Of all the substrates investigated, cassava shavings have the best potential to serve as substrate for fermentation by Penicillium chrysogenum PCL501. © 2009 International Formulae Group. All rights reserved

Production of Biosurfactants by Actinomycetes Isolated from Hydrocarbon Contaminated Soils and Ikpoba River Sediments in Benin-City, Nigeria

The production of biosurfactants by Actinomycetes isolated from hydrocarbon contaminated soils and Ikpoba river sediments were evaluated. Soil samples were collected from mechanic workshops located in various parts of Benin City and Ikpoba river sediments. Physico-chemical analyses were performed. Isolation of Actnomycetes was done using starch casein agar incorporation with antibiotics incubated for 7 – 10 days at 30oC. Growth on mineral salt medium initiated the production of biosurfactants which was extracted by centrifugation and filtration followed by liquid extraction using chloroform: methanol (2:1v/v). Characterization and stability studies were conducted. The pH of the contaminated soil was 4.92 +/- 0.049 while that of Ikpoba river sediments was 6.62+/-0.056. The hydrocarbon contaminated soils had a higher concentration of surphur, nitrogen, potassium, sodium, magnesium and manganese compared to Ikpoba River, but only chlorine concentration was higher in Ikpoba River. Aerobic Gram positive rods with extensive branching were observed confirming growth of Streptomyces sp. The result showed stability across different temperature ranges with no significant difference observed in the two sites in emulsification activity (P&gt;0.05). There was significant difference observed in the mean surface tension of the biosurfactants produced from the two sites across different temperature ranges with hydrocarbon contaminated soil having higher values (P&gt;0.05). There was also significant surface tension difference between pH2 and pH8 (P&lt;0.05) suggesting higher activity within those ranges. The result also show stability across different salt concentrations and had foaming characteristics. Actinomycetes have complex enzymatic mechanism that aids hydrocarbon mineralization and thus increases the potential for biosurfactant production. These biosurfactants are stable across temperature ranges and are not majorly affected by salt concentration; this property aids its potential usage in decontamination of oil contaminated areas in the Niger Delta region of Nigeria and other countries.Keywords: Biosurfactants, Actinomycetes, hydrocarbon contaminated soils and Ikpoba river sediment

Effect of carbon sources on cellulase (EC 3. 2. 1. 4) production by Penicillium chrysogenum PCL501

The effects of glucose, crystalline cellulose and sawdust of Mitragyna cilata on the growth and cellulase production, inferred from cellulase (EC 3. 2. 1. 4) activity, of Penicillium chrysogenum PCL501 was determined. Glucose-containing media gave the highest mycelia weight of 1.78 mg mL-1 in 120 h of incubation. This is about 3.5 – 4.5 times the maximum weights of 0.51 and 0.40 mg mL-1 respectively obtained from the cultures containing cellulose and sawdust. The cultures containing crystalline cellulose and sawdust produced extracellular protein with cellulase (EC 3. 2. 1. 4) activity whereas glucose-containing cultures yielded very low protein and no significant cellulase activity. Maximum protein content of 0.02, 0.13 and 0.46 mg mL-1 respectively were obtained from the cultures containing glucose, cellulose and sawdust. Peak cellulase activity values of 100.0 and 92.2 Units L-1 respectively were obtained for the cultures containing cellulose and sawdust. There is a correlation between the protein released and cellulase activity of the culture filtrates. P. chrysogenum PCL501 produces extracellular proteins with significant cellulase activity in media containing cellulose and sawdust but not in glucose-containing medium. Sawdust is indicated as a good inducer of cellulase activity in the organism. The waste cellulosic material can be used as low-cost carbon source for commercial cellulase production

Xylanase production by Penicillium chrysogenum (PCL501) fermented on cellulosic wastes

Xylanase production by Penicillium chrysogenum PCL501, newly isolated from wood-wastes, was monitored at 24 h intervals for a period 168 h in media containing four different carbon sources (oatspelt xylan, wheat bran, sawdust, and sugarcane pulp). The highest xylanase activity of 6.47 Units mL-1 was obtained at 96 h in media containing wheat bran whereas media containing sugarcane pulp gave a peak value of 1.39 Units mL-1 at 144 h. Sawdust and xylan gave a peak xylanase activity of 1.35 and 0.79 Units mL-1 respectively at 120 h. Maximum protein released in xylan-containing media was 0.38 mg mL-1. Higher protein yield was obtained in media containing the agro-wastes, with wheat bran giving the highest value of 1.14 mg mL-1. The maximum specific xylanase activities were 2.59, 8.52, 16.06, and 9.36 Units mg Protein -1 for sawdust, sugarcane pulp, wheat bran and xylan respectively. Out of the three agro-wastes used in this study, wheat bran holds the greatest promise for cost-effective production of the xylanase enzyme. The carbon source is the highest inducer of the enzyme in the fungus

An in-depth study of patent medicine sellers' perspectives on malaria in a rural Nigerian community

BACKGROUND: Malaria remains a major cause of mortality among under five children in Nigeria. Most of the early treatments for fever and malaria occur through self-medication with antimalarial drugs bought from medicine sellers. These have led to increasing calls for interventions to improve treatment obtained in these outlets. However, information about the current practices of these medicine sellers is needed before such interventions. This study aims to determine the medicine sellers' perspectives on malaria and the determinants that underlie their dispensing patterns of antimalarial drugs. METHODS: The study was conducted in Ugwugo-Nike, a rural community in south-east Nigeria. It involved in-depth interviews with 13 patent medicine sellers. RESULTS: A majority of the medicine sellers were not trained health professionals and malaria is recognized as a major health problem by them. There is poor knowledge and poor dispensing behaviour in relation to childhood malaria episodes. Although referral of severe malaria is common, there are those who will not refer. Verbal advice is rarely given to the care-givers. CONCLUSION: More action research and interventions to improve prescription and referral practices and giving verbal advice to care-givers is recommended. Ways to integrate the drug sellers in the health system are also recommended

Plant Waste Hydrolysis by Extracellular Enzymes of Aspergillus niger and Penicillium chrysogenum: Effect of Ammonia Pretreatment

Aspergillus niger (ANL301) and Penicillium chrysogenum (PCL 501) cultured in basal media with cellulose as sole carbon source yielded extracellular enzymes which partially hydrolyzed sawdust and sugarcane pulp into simple sugars. Pre-treatment of sawdust by ammonium hydroxide steeping increased the yield of simple sugars. The reducing sugars released from the pretreated sawdust by the crude enzymes of A. niger (ANL301) and P. chrysogenum (PCL 501) were 3.58% and 7.02% of the total hydrolysable sugars respectively. This is in contrast to the 0.92% and 1.02% of the total hydrolysable sugars released respectively by the enzymes of A. niger (ANL301) and P. chrysogenum (PCL 501) from the non-pretreated sawdust. Enzymatic hydrolysis of sugarcane pulp by the crude enzymes was not significantly affected by ammonia pre-treatment. Reducing sugars released from non-pretreated sugarcane pulp by the crude enzymes of A. niger (ANL301) and P. chrysogenum (PCL 501) were respectively 4.17% and 5.08% of the total hydrolysable sugars

Parasitaemia and haematological changes in malaria-infected refugees in South Africa

Background. Haematological changes associated with malaria are well recognised, but may vary with level of malaria endemicity and patient background, haemoglobinopathy, nutritional status, demographic factors and malaria immunity. Although malaria in South Africa (SA) has been reduced dramatically in endemic areas, little is known about the haematological changes associated with malaria infection among refugee populations who live in SA cities.Objective. To describe haematological alterations among malaria-infected refugees living in Durban, SA.Methods. A cross-sectional study was conducted from September 2012 to July 2013 inclusive at a refugee centre in central Durban. Blood samples from 102 adult black African refugees were examined for infection with malaria parasites, and haematological profiles were compared with standard normal values.Results. Malaria infection was detected in 16 (15.7%) of the 102 participants. The mean haemoglobin (Hb) value was reduced (mean 9.2 g/dL) in the participants with malaria, who also had an extremely low mean packed cell volume (PCV) of 28.3%. The mean Hb value in the non-malaria-infected participants was normal (12.6 g/dL), and the mean PCV was slightly low (38.0%).Conclusions. Anaemia was more common among participants with malaria infection than among those who were uninfected. Other haematological changes were common in both infected and uninfected participants, suggesting that infections other than malaria, or other underlying factors that cause haematological alterations, may be present. This research needs to be expanded to include a large sample and other areas and infections

Pattern of Blood Pressure Indices among the Residents of a Rural Community in South East Nigeria

Cardiovascular diseases (CVDs) are the main causes of death in industrialized countries, and are significant causes of morbidity and mortality in sub-Saharan Africa. Hypertension is the most common cardiovascular disease in Nigerians, and the risk of CVD associated with hypertension is independent of other risk factors. Despite the high level of awareness of its presence in the developed countries, the level of control is still poor. CVDs tend to be commoner in urban settlements, and it has been hypothesized that rural sub-Saharan Africa is at an early stage of epidemiological transition from communicable to non-communicable diseases (NCD) because of the gradual adoption of unhealthy lifestyles. This study aimed at describing the pattern of blood pressure indices among the hypertensive residents of a rural community in South East Nigeria. A total of 858 individuals comprising 247 males and 611 females took part in the study. 46.4% of the subjects had hypertension. Hypertension was commoner in the males (50.2% vs. 44.8%) (χ2(1) = 1.484; P = 0.223). The males were significantly older and heavier than the females while the females had higher mean values of BMI and WC. The prevalence of hypertension is becoming alarmingly high in the rural communities of sub-Saharan Africa