Search results

This research examines the association of physical development density, prevalence and types of microbes in colonized façade finishes of buildings in Enugu metropolis, Nigeria.

Survey and experimental research designs were adopted. A total of 383 buildings were investigated with samples collected from those with colonized façade finishes. The microbes were identified using the standard procedure for genomic sequencing with descriptive statistics, and the chi-square test used to analyse the data.

The results revealed a 64% prevalence of microbial colonization and a significant association between this and physical development density with 71.0% of the colonized buildings located in high-density neighbourhoods of the metropolis. The sequencing also showed 24 different microbes with Trichophyton tonsurans, Trichophyton mentagrophytes and Trichoderma harzianum species being the most common in the colonized façade finishes.

The research informs building professionals and owners of the specific microbes involved in the colonization of façade finishes of buildings in high-density urban areas. It also provides a clue about the nature of damages and defects associated with microbial colonization of building façades and the type of biocide additives required for the production of microbial-resistant façade finishes in the hot-humid tropical environment of Nigeria and beyond.

The study has shown that there is a significant relationship between the intensity of urban land use and microbial colonization of façade finishes of buildings. It also identified some new or less known microbes responsible for the biodeterioration of façade finishes and the effects this has on the buildings and public health in the hot-humid tropics of Enugu, Southeast Nigeria.

Growth of microorganisms in petroleum products has been recorded since 1895, causing fouling, malfunction and corrosion in storage tanks, airfield equipment, pipelines, airframes and engines. This paper considers the problems that fuel microbes pose to the aviation industry and discusses the International Air Transport Association Aviation Working Group's “Guidance Material on Microbiological Contamination in Aircraft Fuel Tanks”.

Buildings respond differently to microbial invasion depending on the design, type of construction materials and finishes used and extent of exposure to climatic factors. However, in the hot-humid tropical environment of Nigeria, much is not known about how buildings with different types of façade finishes or claddings are liable to microbial decay. The purpose of this research is to investigate the susceptibility of buildings with different types of façade finishes to microbial decay in Enugu metropolis, southeast Nigeria.

A survey involving physical observation of purposively selected 383 buildings and questionnaire administration to their owners was carried out in the study area. The data were subjected to descriptive and logistic regression analyses.

Most of the 383 buildings sampled were less than 41 year and 47% of them had painted façade finishes followed by 25.1% with cementitious finishes. Around 63.4% of the buildings had their façade finishes or claddings colonised by microbes. Older buildings of 15 years and above and those with cementitious materials and paints as their predominant façade finishes were more likely to experience microbial decay than newer ones and those having refractory bricks, ceramic tiles, aluminium composite materials and plastics/polymers as their predominant façade finishes or claddings.

The study identifies the categories of buildings that are likely to be more susceptible to microbial decay; and thus contributes to research on how to slow down the rate of biodeterioration of building façade finishes or claddings in the hot-humid tropical environments.

This is the first study on the susceptibility of buildings with different types of façade finishes or claddings to microbial decay in the hot-humid tropical environment of Enugu metropolis, southeast Nigeria. It also provides a clue on the age at which buildings become more vulnerable to microbial decay in the study area.

MR. F. W. F. ARNAUD, the Public Analyst for the Borough of Portsmouth, delivered a lecture on this subject at the Town Hall on April 27. The lecturer commenced his address by stating that many of the objections to the use of certain preservatives which he might have occasion to put forward were not necessarily his own individual objections, but were the objections of many scientific men who had dealt with all sides of this difficult subject. There was a tendency on the part of some people to regard preservatives as disinfectants, but disinfectants and antiseptics were two different things. A disinfectant not only retarded the growth of microbes, but actually killed them, while an antiseptic preservative merely retarded their growth or formation. Two common antiseptics were sugar and salt. It had been contended that a small dose of a chemical preservative was preferable to a dose of microbes. The effect of a preservative was not to kill the life already present, but to prevent the free multiplication of the organisms present, and the swallowing of a dose of preservative did not necessarily prevent the swallowing of a dose of microbes. There were many old forms of preserving food, such as the use of sugar for fruit and condensed milk; of vinegar for vegetables; and the process of smoking for bacon and fish, smoke being very destructive to microbes; but the oldest form of preservation was the process of salting meat and fish. Another form of preservation was the method of preventing the access of air to perishable articles, as in the cases of eggs and lard. Then there was drying, as in the case of fruit, and chilling, or freezing, as in the cases of meat, milk, poultry, and fish. The temperatures employed for freezing food varied considerably, and depended chiefly upon the length of time during which storage was necessary. If it were only desired to keep meat for a week or two, a low temperature was not necessary, but one of 40 deg. F. was sufficient. Any cooling process was equivalent to the use of a great deal of chemical preservative. A cooling to 50 deg. P. was equivalent to the addition of boric acid to the extent of .05 per cent. At a normal summer temperature of 70 deg. P., two microbes would produce 62,100 in the course of twenty‐four hours; hence the necessity for cooling articles of food. The drawback to most of these methods of preservation was that sugar, salt, and cold were not applicable in every case. Exclusion of air and subsequent sterilisation had their drawbacks also. When sterilisation was complete and the air was exhausted, no putrefaction could take place, and the food should remain indefinitely unchanged. In the matter of tinned meat, the drawback lay chiefly in the failure to ensure complete sterilisation, and in the dissolving of tin, and occasionally lead, from the metal enclosing the food. In the case of tinned meat putrefaction to any considerable extent could be easily recognised by the blown condition of the tin and an absence of the inrush of air when the tin was pierced. Such food was a source of great danger, and if eaten the meat was liable to give rise to ptomaine poisoning—which was occasioned by eating the poisonous products produced by various bacteria. The danger of metallic poisoning could be largely overcome by the use of glass or earthenware vessels. Preservatives in use at the present time were: Benzoates, fluorides, formalin, salicylic acid, sulphites, saccharin, and beta naphthol, generally used singly, though there were some very complicated preservatives on the market. With reference to the use of salt and sugar as preservatives, little or nothing could be said against their use, for sugar was in itself a food and had a well‐known food value. Salt, too, was an essential constituent of our food, for without the elements of which it was composed we could not exist. Naturally, the assimilation of a large quantity of salt was not desirable, but it could not be urged, as, for instance, in the case of boric acid, that it was a substance foreign to the constituents of the human organism, for it was indispensable. Boric acid, however, played no part in any of the essential life processes.

The purpose of this paper is to study the metal-Microbe interaction playing a crucial role in microbiologically influenced corrosion (MIC) and biofouling of materials in cooling water systems. Treatment regimens should be planned based on this understanding.

Attempts were made in the past decades to characterize and understand biofilm formation on important power plant structural materials such as carbon steel (CS), stainless steel (SS) and titanium in fresh water and in seawater to achieve better control of biofouling and minimize MIC problems.

This report presents the results of detailed studies on tuberculation-formed CS because of the action of iron-oxidizing bacteria and the effects of algae- and bacteria-dominated biofilms on the passivity of SS. The preferential adhesion of different bacterial species on SS under the influence of inclusions and sensitization was studied in the context of preferential corrosion of SS weldments due to microbial action. Detailed characterization of biofilms formed on titanium (the likely condenser material for fast breeder reactors) after exposure for two years in Kalpakkam coastal waters revealed intense biofouling and biomineralization of manganese even in chlorinated seawater. Studies on the effectiveness of conventional fouling control strategies were also evaluated.

The detailed studies of different metal/biofilm/microbe interactions demonstrated the physiological diversity of microbes in the biofilms that were formed on different materials, coupling their cooperative metabolic activities with consequent corrosion behaviour. These interactions could enhance either anodic or cathodic reactions and exploit metallurgical features that enhance biofilm formation and/or the capacity of microbes to mutate and overcome mitigation measures.

When carrying out bioremediation of water polluted by biomass‐oil, the stains which can degrade the biomass‐oil efficiently should first be found. The purpose of this paper is to describe how adopted acclimation through the isolated strains degraded efficiently, and got reaction kinetics property.

During the acclimation, the biodegradation process of biomass‐oil is accorded approximately with the first‐order reaction by the way of Sturm method which is described by measuring CO₂ volume from the microbes' production.

One kind of microbe, Aspergillus versicolor, separated from the activated sludge in the aeration tanks of paper‐mill, is found to have the advantage of biodegradation in case of biomass‐oil from rice straw by rapid thermal‐liquidizing process. The biodegradation ability could be improved in aqueous culture under neutral and acidic conditions. The optimal temperature for biodegradation of biomass‐oil is 40°C. The optimal inocula content for biodegradation of biomass‐oil was 16 vol%.

The variation of lubricity of biomass‐oil with biodegradation needs more attention.

A basic research on the growth of a strain is shown, which is helpful for the biological treatment of biomass‐oil pollution.

One kind of fungi, Aspergillus versicolor, can be used for the biodegradation of biomass‐oil. The effects of various conditions or parameters on biodegradation of biomass‐oil are discovered in aqueous culture conditions in the case of Aspergillus versicolor.

That ice‐creams prepared with dirty materials and under dirty conditions will themselves be dirty is a proposition which, to the merely ordinary mind, appears to be sufficiently obvious without the institution of a series of elaborate and highly “scientific” experiments to attempt to prove it. But, to the mind of the bacteriological medicine‐man, it is by microbic culture alone that anything that is dirty can be scientifically proved to be so. Not long ago, it having been observed that the itinerant vendor of ice‐creams was in the habit of rinsing his glasses, and, some say, of washing himself—although this is doubtful—in a pail of water attached to his barrow, samples of the liquor contained by such pails were duly obtained, and were solemnly submitted to a well‐known bacteriologist for bacteriological examination. After the interval necessary for the carrying out of the bacterial rites required, the eminent expert's report was published, and it may be admitted that after a cautious study of the same the conclusion seems justifiable that the pail waters were dirty, although it may well be doubted that an allegation to this effect, based on the report, would have stood the test of cross‐examination. It is true that our old and valued friend the Bacillus coli communis was reported as present, but his reputation as an awful example and as a producer of evil has been so much damaged that no one but a dangerous bacteriologist would think of hanging a dog—or even an ice‐cream vendor—on the evidence afforded by his presence. A further illustration of bacteriological trop de zèle is afforded by the recent prosecutions of some vendors of ice‐cream, whose commodities were reported to contain “millions of microbes,” including, of course, the in‐evitable and ubiquitous Bacillus coli very “communis.” To institute a prosecution under the Sale of Food and Drugs Act upon the evidence yielded by a bacteriological examination of ice‐cream is a proceeding which is foredoomed, and rightly foredoomed, to failure. The only conceivable ground upon which such a prosecution could be undertaken is the allegation that the “millions of microbes ” make the ice‐cream injurious to health. Inas‐much as not one of these millions can be proved beyond the possibility of doubt to be injurious, in the present state of knowledge; and as millions of microbes exist in everything everywhere, the breakdown of such a case must be a foregone conclusion. Moreover, a glance at the Act will show that, under existing circumstances at any rate, samples cannot be submitted to public analysts for bacteriological examination—with which, in fact, the Act has nothing to do—even if such examinations yielded results upon which it would be possible to found action. In order to prevent the sale of foul and unwholesome or actual disease‐creating ice‐cream, the proper course is to control the premises where such articles are prepared; while, at the same time, the sale of such materials should also be checked by the methods employed under the Public Health Act in dealing with decomposed and polluted articles of food. In this, no doubt, the aid of the public analyst may sometimes be sought as one of the scientific advisers of the authority taking action, but not officially in his capacity as public analyst under the Adulteration Act. And in those cases in which such advice is sought it may be hoped that it will be based, as indeed it can be based, upon something more practical, tangible and certain than the nebulous results of a bacteriological test.

Purpose – This study was conducted to determine the effect of peel of Arabica coffee (PAC) with Win Prob Probiotic on crude fiber content and fiber fraction (neutral detergent fiber, NDF; acid detergent fiber, ADF; cellulose; hemicelluloses; and lignin). The hypothesis of this study is that PAC fermentation using Probiotic Win Prob can decrease the content of crude fiber and fiber fraction.

Design/Methodology/Approach – The research design applied was a factorial completely randomized design with three treatments and three replications. Factor A (probiotic dose) consisted of three doses: 2.5%, 5%, and 7%, in addition, there are three fermentation durations considered as factor B, which are 20, 30, and 40 days.

Findings – The result of this study indicates that the content of crude fiber and fiber fractions can decrease each amount of the variable of this study. The best treatment was obtained in A3B3 with 7% probiotic with 30 days of fermentation. Rough fiber PAC decreased up to 27.66% and NDF content decreased by 3.6%. Moreover, ADF content decreased up to 4.10%. The last lignin decreased by 18.75%.

Research Limitations/Implications – Only a small portion of coarse fiber and fiber fractions in PAC is fermented with Win Prob probiotics. So we can try other ways to reduce the coarse fiber and PAC fiber fractions such as the combination of ammonium and fermentation (amofer).

Originality/Value – The PAC has a high content of crude fiber and fiber fractions (NDF, ADF, cellulose, hemisellulose, and lignin), and so it is recommended as ruminants for feed ingredients.

The issue of the genetic manipulation of plants, animals and microbes is addressed within the context of food production. Genetic manipulation is defined within the wider area of biotechnology and some of the main benefits of its use are summarised; safety and risk are examined and some of the socioeconomic problems it can create are discussed. It is concluded that the technique can offer great potential benefits in terms of increased quantity and improved quality of food, but it raises social/ethical concerns which can be summed up by asking: Is it safe? Is it fair? Is it natural?