Showing papers in "International Journal of Biosciences in 2012"

Major component and potential applications of plant essentials oils as natural food preservatives: a short review research results.

Abstract: The present review takes in account studies relative to the potential applications as natural food preservatives and major components of essential oils extracted from some aromatic edible herbs and spices Allium sativum, Cinnamomum zeylanicum, Cympobopon citratus, Mentha piperita, Pimenta racemosa, Ocimum gratissimum, Syzygium aromaticum, Xylopia aethiopica and Zingiber officinale. Therefore, some informations relative to antibacterial and antifungal efficiency of these essential oils on either foods pathogens responsible for humans foodborne diseases and foods deterioration and its poor quality (bacteria: Escherichia coli, Salmonella, Listeria monocytogenes, Staphylococcus aureus; more pathogen yeast Candida albicans and moulds: Aspergillus, Fusarium and Penicillium) are presented. Furthermore, this short review doesn’t occult its main highest elevation which is the presentation of main components and interesting potential applications as food preservatives of these essentials oils. Their application as natural preservatives of traditional cheese Wagashi product in Benin will be tested.

Chemical composition and biological activities of essential oils of Chenopodium ambrosioides L. collected in two areas of Benin.

Abstract: The chemical composition of the essential oils obtained by hydrodistillation from leaves of three samples of Chenopodium ambrosioides L. (Chenopodiaceae) growing in Benin were analyzed by GC and GC/MS. To date the biological functions of Chenopodium ambrosioides L. essential oils have not been demonstrated scientifically. We investigated the chemical composition of Chenopodium ambrosioides L. essential oils and their antiradical antimicrobial and anti-inflammatory activities. Twenty three compounds were identified and quantified in the oils. The essential oils are rich in hydrocarbons monoterpenic. The major compounds being ?-terpinene (48.8%, 60.0%, 63.7%), ascaridole (19.7%, 13.8%, 11.7%), p-cymene (19.1%, 15.4%, 19.0%) and isoascaridole (2.5%, 1.6%, 0.7%). The antiradical and anti-inflammatory. (Resume d'auteur)

L-asparaginase gene - a therapeutic approach towards drugs for cancer cell.

Abstract: L-asparaginase is an enzyme that reduces the activity of L-asparaginase (an important nutrient for cancer cells) resulting in cancer/tumor cell starvation). L-asparaginase is relatively wide spread enzyme found in many plant tissue, bacteria, plant and in the serum of certain rodents, but not of man. It is used mainly for the induction of remission in acute lymphoblastic leukemia. Although there are therapeutic asparaginases present in the market, recent discoveries have indicated that the L-asparaginase from Erwinia carotovora (ErCAR) might be more efficient and also to exhibit fewer side effects. The need for new therapeutic enzymes is of great interest in both biotechnology and medicine. This paper is an attempt to comprise detailed information of the work on the L-asparaginase gene from different sources for the treatment of cancer cells.

Physicochemical, rheological and thermal properties of taro (Colocassia esculenta) starch harvested at different maturity stages

Abstract: The objective of this study was to evaluate the effects of tubers maturity stage on the physicochemical characteristics and thermal properties of Colocasia esculenta (Sosso ecotype) starches. Plantation was done in Chad, tropical area from May to February following a randomized design with 5 maturity stages (6, 7, 8, 9 and 10 months after planting) as the main treatments. The results showed significant increase in phosphorus content (from 113.99 to 145.64µg/100g), temperature (from 80.69 to 84.54°C) and enthalpy of gelatinization (from 13.24 to 16.27 J/g), water absorption capacity (from 140.11 to 304.48 %), solubility index (from 17.50 to 29.42%) and swelling index (from 115 to 135%). In addition the monomolecular moisture content (varying from 2.67 to 3.36 %) and the GAB constant C (varying from 11.73 to 113.22) exhibited significant increase with maturity. Furthermore, a significant decrease in amylose content (from 35.90 to 27.65%) was observed as the maturity increases. In conclusion and on the basis of the correlation observed, the changes in phosphorus and amylose composition of starch during growth seemed to play a role not only on the molecular structure of the starch granules, but also on its functionality.

Study of some ethnomedicinal plants for treatment of dysentery of North Coastal Andhra Pradesh, India

Abstract: Paper deals with some medicinal plants of North Coastal Andhra Pradesh to treat dysentery disease (Infection of the intestines with bacteria or protozoans, resulting in severe diarrhoea with blood and mucus in the faeces) with help of medicinal plants. 40 plant species are recorded as medicinal plants which are used by the tribal people of North Coastal Andhra Pradesh. Out of these 40 plant species 17 trees, 11 herbs, 7 climbers and 5 are shrubs. The 40 plants are being used commonly for dysentery, Root is used in a quantum of 28%, leaf in 21%, stem bark (12%), tuberous / seeds / tubers / fruit (2%), each. Stem (2.41%), gum (5%), whole plant (14%) and flower (3%). These findings warn us from popularization of ethnomedicinal practices in dysentery before alternate steps are taken up to grow medicinal flora in a campaign approach. Phytochemical studies of above said plants need to be taken up to find out the exact ingredients that help in the curing of dysentery. The exploitation of medicinal plants for their economic value and use must be carried out, but proper care should be taken for their conservation by both in-situ as well as ex-situ conservation methods.

Biochemical changes of common bean (Phaseolus vulgaris L.) to pretreatment with salicylic acid (SA) under water stress conditions

Abstract: Salicylic acid (SA) is one of the important signal molecules which modulating plant responses to environmental stresses including drought. An experiment was therefore, conducted to evaluation the effect of exogenous SA on the lipid peroxidation, antioxidant enzymes activities and proline content of common bean under water stress conditions during 2011 in Iran. Results showed that drought increased membrane lipid peroxidation via increase of malondialdehyde (MDA) content as well as some antioxidant enzymes activities such as superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) and proline level. Nonetheless, seeds soaking in SA (especially 0.5 mM) alleviated drought injuries by way of decrease of lipid peroxidation through reduce of MDA content and further increase in antioxidant enzymes activities especially SOD and proline level. Results signify that exogenous SA could help reduce the adverse effects of drought stress and might have a key role in common bean tolerance to drought by decreasing oxidative damage via further activities of antioxidant enzymes and more proline accumulation.

Ethnobotanical studies on useful plants of Sirumalai Hills of Eastern Ghats, Dindigul district of Tamilnadu, southern India.

Abstract: The present investigation is an attempt to an ethnomedicinal plants survey carried out in Sirumalai Hills of Eastern Ghats, Dindigul district of Tamilnadu. The indigenous information of the village dwellers, tribal people, village herbalists, herbal practitioners and other traditional healers and the indigenous plants used for medicinal worthiness were collected through personal interviewes and questionnaire during field trips. The exploration revealed some unknown medical uses of medicinal plants. The locals use 44 medicinal plants for the treatment of several diseases either in single or in combination with some other ingredients. The information on correct botanical identities with family, vernacular name (Tamil), part used and traditional practice of 44 species, 40 genera and 28 families of angiosperms are discussed here for the treatment of various illnesses viz., asthma, snake bite, anthelmintic, promote coolness antipyretic, jaundice, diarrhoea, dysentery, leprosy, diuretic, diabetes, stomachache problems, paralysis and skin diseases. The dicotyledons are represented by 41 species of 37 genera and 25 families while monocotyledons are represented by 3 species of 3 genera and 3 families. The plant parts are used in the form of juice, extract, powder and paste. These uses are noteworthy for further investigation on recent scientific manner. The present study concluded that the abundance of natural ethnomedicinal information of medicinal plants may also points to a excellent potential for investigation in the discovery new medicines to fight ailments and other new uses.

Determination of coffee origin by using 28S rDNA fingerprinting of fungal communities by PCR-DGGE: application to the Cameroonian coffee.

Abstract: The new European regulation 178/2002 imposes the determination of the geographical origin in the traceability process of foodstuffs at the moment of commercial transactions. In practice, it is difficult to determine with accuracy the geographical origin of foodstuffs. For this purpose, the total analysis of fungal communities in samples of coffee is used. In the present study the molecular technique using 28S rDNA profiles generated by PCR-DGGE was used in order to detect the variation in fungal community structures of coffee from five different locations in West and Coastal plain in Cameroon and the effect of treatment and coffee species on these fungal profiles. When the 28S rDNA profiles were analyzed by multivariate analysis, distinct microbial communities were detected. The band profiles obtained from different samples of coffee and specific for each location and could be used as a bar code to certify the origin of the coffee. This method is a new traceability tool which provides coffee products with a unique biological bar code and makes it possible to trace back the coffee to their original location. (Resume d'auteur)

Chemical composition and biological activities of essential oils of Pimenta racemosa (Mill.) J. W. Moore. from Benin.

Abstract: The aim of the present work was to assess potential antiradical, anti-inflammatory and antimicrobial activities of essentials oils of Pimenta racemosa from Benin. The chemical compositions of the essential oils obtained by hydrodistillation from fresh leaves of six samples of Pimenta racemosa (Mill.) J. W. Moore. (Myrtaceae) growing wild in Benin were analyzed by GC and GC/MS and showed twenty four compounds identified and quantified in the essential oils with eugenol (45.2% - 52.7%), myrcene (25.1% - 29.4%), chavicol (7.1% - 9.3%), limonene (3.0% - 4.0%), 1,8-cineole (2.1% - 3.2%) as major compounds. The evaluation of biological activities of these oils has shown a low anti-inflammatory activity and high antiradical, acaricidal against Amblyomma variegatum and antimicrobial activities against both bacteria and fungi. Fractionation of an eugenol rich sample allowed the identification of the bioactive fractions and their contribution to the efficiency of the whole extract. This study suggests that P. racemosa essential oils may be useful in the food industry where the antioxidants are used to delay the degradation of fatty substances. Fractionation of an eugenol rich sample allowed the identification of the bioactive fractions and their contribution to the efficiency of the whole extract. This study suggests that P. racemosa essential oils may be useful in the food industry where the antioxidants are used to delay the degradation of fatty substances.

Impact of dam construction on the diversity of benthic macroinvertebrates community in a periurban stream in Cameroon

Abstract: In the aim of evaluating the impact of a dam construction on the biodiversity of aquatic organisms, physicochemical variables coupled to benthic macroinvertebrates communities were analysed at the upstream and downstream of the Mefou stream dam from September 2009 to March 2010. Physicochemical results revealed a slightly acidic and well oxygenated water of the Mefou stream, being appropriated for the development of benthic macroinvertebrates organisms. Significant differences were observed for temperature and oxygen between the stations (P < 0.05). Of the 1801 individuals collected (4 phyla, 6 classes, 13 orders, and 47 families), Arthropods (99.25%) dominated, while Annelids, Nemathelminths and Mollusca were less represented (2 %). The Correspondence Canonic analysis (CCA) distinguished two sections on the stream: a superior section at the upstream of the dam which is characterised by much oxygenation and abundance of Atyidea (excellent bioindicators of good quality water) (r = 0.04; P < 0,05); an inferior section at the downstream of the dam, dominated by rheophil organisms (odonates). The relative abundance of odonates correlated with the values of water flow rates of each station (r = 0.94 ; P < 0.01). The presence of polluo-tolerant organisms (Chironomidae and Haplotaxidae) at station 3 could reflect anthropic action at the downstream of the dam. Shannon and Weaver (H = 4.1±0.5 bits) and Pielou index (J = 0.8 ± 0.1bits) revealed favourable conditions for the coexistence of benthic macroinvertebrates. This results could provide viable information used in evaluating the water quality of lotic systems subjected to dam construction in Cameroon.

Removal of ash from sugarcane leaves and tops.

Abstract: This paper presents findings on the removal of ash from sugarcane leaves tops by applying two main techniques including biomass size selection and biomass washing. In the size selection technique, biomass samples were ground and sieved into <0.250, 0.250-0.425, 0.425-0.85 and 0.85-2.00 mm. In the washing technique, samples were washed with water and dilute acid solution. The biomass samples after being subjected to both techniques were analysed for their ash content. The result showed that the biomass particle size of 0.85-2.00 mm gave lowest ash content for both sugarcane leaves and sugarcane tops. It was also found that the effectiveness of the removal of ash from sugarcane leave and tops was mainly dependent on the washing solution and residence time applied. The most effective method for the ash removal was by hot water for 24 hours, which could remove up to 65.35% and 69.01% of the ash in sugarcane leave and tops.

Nutritive compositions of locally available jackfruit seeds (Artocarpus heterophyllus) in Bangladesh

Abstract: The nutritive value of jackfruit seeds was investigated using the following parameters -proximate composition and mineral composition. The aim of this study is to determine the physico-chemical properties of jackfruit seeds. Three types of jackfruits namely Khaja (green, hard and smooth, with juicy pulp and small seeds), Gala (rough, soft, with thin pulp, not very juicy, and large seeds) and Durosha (rough, soft, intermediate size of pulps and seeds) were taken under investigation. The fruits were cut, the seeds removed, sliced, dried at 60 °C for 24 hrs, packaged in polyethelyne bag and kept in a refrigerator (~20±2° C). The moisture content, dry matter and ash content was found around 21.10- 42.25%, 57.75- 78.90% and 2.13- 4.07% respectively among the varieties. A good amount of protein content was found in all varieties of jackfruit seeds, it ranged from 13-18%. Crude fibre content of seed varied from 1.56-2.60%. Jackfruit is a good source of many mineral contents like N, P, K, Ca, Mg, S, Zn, Cu etc. Starch content in seed was found from 12.86- 17.90%. The information achieved from the study could be helpful for the students, teachers, scientists who has been engaged with the biochemical analysis of different types of jackfruits in Bangladesh.

Chemical composition and in vitro antifungal activity of Zingiber officinale essential oil against foodborne pathogens isolated from a traditional cheese wagashi produced in Benin

Abstract: The aim of the present work was to assess some antifungal activity parameters as mycelial growth inhibition, minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of Zingiber officinale essential oil from Benin against Aspergillus (flavus and tamarii), Fusarium (poae and verticillioides) and Penicillium (citrinum and griseofulvum) species isolated from traditional cheese wagashi. The chemical composition of the essential oil extracted by hydrodistillation with Clevenger apparatus from fresh rhizomes of ginger was studied by GC-FID and GC-MS and showed -zingiberene (40.7%) as major component with minor compounds in significant percents such as geranial (8.9%), elemol (5.9%), neral (4.5%), camphor (4.3%), limonene (3.7%) and (E, E)-α-farnesene (3.6%). The evaluation of antifungal activity of this oil has shown a less activity against all the species tested with mycelia growth inhibition not exceeding 79.66% excepted Penicillium griseofulvum on which the oil had fungistatic activity with MIC equal to 1000 mg/L. Results obtained in the present study reveal that Zingiber officinale essential oil is not a good antifungal agent against moulds species responsible for wagashi deterioration. Its activity may be improved by its combination with other natural active products.

Antiradical activity and polyphenol content of ethanolic extracts of Propolis.

Abstract: Propolis is a natural substance produced by honeybees from resinous products collected from plants. Its ethanolic extract is currently commercialised in Cameroon under the brand name Promax C. This study investigated the total polyphenols, tannins and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging activity of Promax C (6 samples) compared to the freshly ethanol extracted propolis (15 samples). The results revealed that all Promax C samples tested showed evidence of radical scavenging properties with values ranging from 28 to 70 %. Although the ethanolic samples had lower phenol contents (8.6 – 17.0 g/100 g), their anti-oxidant activities (38.8 - 85.9 %) were systematically higher than those of Promax C. In addition the Promax C manufactured in 2006 systematically exhibited the highest scavenging activity (67.3%) and polyphenol contents (772.8 mg/L) compared to those manufactured in 2004 (mean scavenging activity 43.7 %; mean polyphenol contents, 227.8 mg/L). While there was a linear relationship between the radical scavenging activity and the polyphenols or tannin content in the Promax samples, this was not the case with the fresh ethanolic extract. The Cameroonians propolis exhibited higher scavenging activity which could justify their commercialisation and role in the management of some chronic diseases. However, the activity of Promax tends to decrease with aging, and this needs to be investigated.

Effect of bio compost, cow dung compost and NPK fertilizers on growth, yield and yield components of chili.

Abstract: To investigate the effects of bio compost, cow dung compost and NPK fertilizers on growth, yield and yield components of chili the experiment was conducted randomized block design with three replications at Botanical Garden of Rajshahi University Campus, Bangladesh during August 2008 to February 2009. There were 15 treatments viz. T1 = bio compost (3 kg/pot) + NPK, T2 = bio compost (2 kg/pot) + NPK, T3 = bio compost (1.5 kg/pot) + NPK, T4 = bio compost (3 kg/pot), T5 = bio compost (2 kg/pot), T6 = bio compost (1.5 kg/pot), T7 = cow dung compost 3 kg/pot + NPK, T8 = cow dung compost (2 kg/pot) + NPK, T9 = cow dung compost (1.5 kg/pot) + NPK, T10 = cow dung compost (3 kg/pot), T11 = cow dung compost (2 kg/pot), T12 = cow dung compost (1.5 kg/pot), T13= NPK, T14= bacterial suspension, T15= control (only soil). Bio compost and NPK significantly (p=0.05) influenced the growth and yield of chili. The treatment bio compost (3kg/pot) +NPK (T 1) produced the highest germination (%), vigour index, growth and yield of chili and the lowest yield and yield contributing parameters were recorded in control (T15). The correlation matrix showed that yield per plant of chili had significant and positive correlation with plant height (r = 0.929**), leaf number (r = 0.808**), number of primary branch (r = 0.918**), secondary branch (r = 0.985**), root number (r = 0.953**), root length (r = 0.947**), total number of flower at maximum flowering time(r = 0.981**), total number of fruit ( r = 0.966**), fruit length (r = 0.917**), fresh fruit weight ( r = 0.990**), dry fruit weight ( r = 0.800**), number of seed/ fruit (r = 0.861**) and hundred seed weight ( r = 0.954**) and yield was significant and negative correlation (r = -0.906**) with number of days required for first flower initiation. The results suggest that inorganic fertilizers (NPK) with bio compost (3kg/pot) is suitable for better production of chili that may increase soil fertility and this integrated approach could be contributed to improve crop production.

Comparison of autumn and spring sowing on performance of chickpea (Cicer arietinum L.) varieties

Abstract: Sowing time and variety are two important factors which influence crop performance including chickpea. In order to investigate the effects of autumn and spring sowing dates on yield and yield components of chickpea varieties a field experiment was carried out in Shahre-Rey region, in south of Tehran, Iran during 2010/2011. The experiment was laid out in factorial arrangement on the basis of randomized complete block design with four replications which five sowing dates (October 12, November 02 and November 22 as autumn sowing dates and March 16 and April 06 as spring sowing dates) and five chickpea varieties (Arman, Azad, Hashem, ILC1799 and ILC482) were treatments. Results showed that the longer growing period of autumn-sown chickpeas affected positively characters contributing to yield such as biomass, pods per plant, seeds per pod, 100-seeds weight and harvest index, which in turn contributed to increased seed yield. Varieties had significant effects on all measured traits. Except ILC482 other varieties gave higher seed yield in autumn sowing. The degree of superiority of seed yield in autumn sowing as compared to spring was strongly affected by the environmental conditions and tolerance of varieties to cold stress. The maximum seed yield (612.8 g m -2 ) was recorded with ILC1799 sown on November 02.

Tolerance potential of fungi isolated from polluted soil of Multan, Pakistan

Abstract: Filamentous fungi were isolated from polluted peri-urban area of Multan, Pakistan and the tolerance potential of fungal strains i.e., Aspergillus niger against specific metals Cr(NO3)3, Pb(NO3)2 and ZnCl2 were tested on Potato Dextrose Agar (PDA) plate. The degree of tolerance is measured through minimum inhibitory concentration (by applying different concentrations of metals). Tolerance potential showed either tested isolates are tolerant, moderately tolerant or sensitive. The findings of present study is depicted that Aspergillus niger showed different tolerance behaviour for different metals at different concentrations such as chromium and lead are more tolerated as compared to Zinc. The knowledge of the present study will be helpful for further research of biosorption and bioremediation potential of fungi and used them for applied side.

Antibacterial and mycelial growth inhibition of some acylated derivatives of D-glucopyranoside

Abstract: Methyl 4,6-O-benzylidene-α-D-glucopyranoside acylated derivatives (2-12) were employed as test chemicals for in vitro antimicrobial evaluation against four Gram-positive and six Gram-negative human pathogenic bacteria and three phytopathogenic fungi. It was revealed that a good number of tested chemicals exhibited moderate to good antimicrobial activities. It was found that these tested compounds were more effective against the phytopathogenic fungi than those of the bacterial strains. However, Methyl 4,6-O-benzylidene-2-O-(4-t-butylbenzoyl)-3-O-lauroyl-αD-glucopyranoside (6) (19.5 mm) exhibited better antibacterial activity than the standard antibiotic, ampicillin (18 mm). Also, it has been observed that the mycelial growth inhibition of methyl 4,6-O-benzylidene-2-O-(4-tbutylbenzoyl)-3-O-(2,6-dichlorobenzoyl)-α-D-glucopyranoside (11) showed the highest inhibition (53.84%) against the Fusarim equiseti than that of standard antibiotic, nystatin (44.70%).

Effect of storage on chemical composition and mycoflora of okra (Abelmoschus esculentus).

Abstract: The mycoflora of sundried okra (Abelmoschus esculentus) during twenty weeks of storage and the effects of their presence on the nutrient composition were investigated. Six fungi were isolated namely: Rhizopus sp., Mucor sp., Aspergillus niger, Aspergillus flavus and Neurospora crassa. The fungi were found to increase as the storage time increases though constancy exists. The results of proximate composition in g/100g showed that ash decreased from 8.06 to 7.56, crude protein 14.54 – 12.68, fat content 9.75 - 6.94, Fibre 36.66-35.75 while the following parameters were found to increase viz moisture 9.83-14.53 and carbohydrate 21.17-22.99. The results of mineral analysis in mg/100g revealed that all minerals decreased with storage period viz sodium (Na) 55.30 54.68, calcium (Ca) (81.65-80.75), iron (Fe) 0.68 – 0-50, magnesium (Mg) 75.60 – 72.43, zinc (Zn) 38.10 – 31.82, manganese (Mn) 1.75 – 0.75 and phosphorus (P) 63.5 – 61.49 but potassium (K) increased from 60.50 – 60.84. Copper (Cu) and Lead (Pb) were not detected in the samples. The nutritional composition of okra was depleted during storage. Therefore, storage should be done under controlled environment that will not favour the growth of spoilage microorganisms.

Identification of salt tolerant rice genotypes and their genetic diversity analysis using SSR markers.

Abstract: Twenty six rice germplasms were used to evaluate salinity tolerance at the seedling stage. Salinity and nonsalinized setup were maintained at seedling stage. Phenotyping for salinity screening of the rice genotypes was done using salinized (EC level 12 dS /m) nutrient solution in hydroponic system following IRRI standard protocol. Genotypes were evaluated individually for salinity tolerance on 1-9 scale on the basis of seedling growth parameters following modified SES of IRRI. At the seedling stage, sixteen moderately tolerant and ten susceptible genotypes were identified using Standard Evaluation Score (SES).On the basis of SES score and phenotypic performance, out of 26 rice germplasms two (BINAdhan-8 and AYT SL-3)were selected as compare to other germplasms. For genotypic salt tolerance of 26 rice germplasms, DNA was extracted from leaf samples using CTAB mini-prep method. Then six selected SSR markers viz., RM10701, RM304, RM11757, RM336, RM7075, and RM152 were used for identification of salt tolerant genotypes. The band obtain from reaction with different markers were compared to the selected genotypes (BINAdhan-8 and AYT SL-3). Assessment of genetic diversity is an essential component in germplasm characterization and conservation. In DNA profiling, a total of 60 alleles were detected with an average number of alleles of 10 per locus (range 8 to 12 per locus) and the PIC values ranged from a low of the 0.7459 (RM152) to a high of 0.8908 (RM10701) and averaged 0.857. Positive correlations were found between gene diversity, PIC value and number of allele. The Unweighted Pair Group Method of Arithmetic Means (UPGMA) dendrogram constructed from (Nei’s, 1972) genetic distance produced two main clusters of 26 rice germplasms. The lowest genetic distance (0.200) was found in CSR-28 vs. CSR90IR-2 genotype pair indicating that they are genetically much closer among the genotypes. A cluster was consisted with a moderate salt tolerant due to higher similarity, while the mostly susceptible germplasms in the second cluster due to lower genetic distance between germplasms.

Impact of heavy metals and Hsp Response

Abstract: Heavy metals are natural constituents of the earth's crust, but indiscriminate human activities have drastically altered their geochemical cycles and biochemical balance. Heavy metals such as Iron, copper, Zinc, Nickel, Molybdenum are essential for normal biological functioning. Heavy metals such as Mercury, Lead, and Cadmium are biologically non-essential, but are important metals for industrial applications. Prolonged exposure to heavy metals such as cadmium, copper, lead, nickel, and zinc can cause deleterious health effects in plants, fishes and humans. Higher concentrations of both essential and non-essential metals disturb normal biological functions and which evoke cellular stress responses. Prolonged exposure of heavy metals induces heat shock proteins in plants, animals and fishes. Heat shock proteins are expressed in response to a wide range of biotic and abiotic stressors. Heat shock proteins are a family of highly conserved cellular proteins present in all organisms including fish, plant and humans. This review focus the toxic effects of heavy metals and the significance of heat shock proteins in response to stress in plant, fish and human

Evaluation of the effects of cassava mill effluent on the microbial populations and physicochemical parameters at different soil depths.

Abstract: The effect of cassava mill effluent on the microbial populations and physicochemical parameters of the soil at various depths was studied. The result revealed the bacterial isolates as Proteus mirabilis, Proteus vulgaris, Bacillus sp, Staphylococcus saprophyticus, and Klebsiella sp, Streptococcus sp, while the fungal isolates were Aspergillus sp, Penicillium sp, Mucor sp and Rhizopus sp. In addition, total aerobic bacterial count results at P 0.05. The pH, cyanogenic glycosides, and C/N ratio all increased with depths while %OC, %N, %OM and ECEC decreased with depth. Cassava mill effluent has negatively affected the microbial populations and physicochemical parameters at various depths.