Pitting corrosion evaluation: a review

Pitting corrosion is an insidious localized form of corrosion causing much devastating destruction to structural members such as stainless steel in chloride environment. This paper gives a review of the mechanism processes of pitting, stages, factors facilitating pitting corrosion, techniques of evaluating pitting corrosion and some research work on pitting corrosion. The rudimentary knowledge of the mechanisms of pitting corrosion from this work will be of assistance to the selection process, specification and the use of stainless steels and other structural members

An overview of anti-diabetic plants used in Gabon: Pharmacology and Toxicology

© 2017 Elsevier B.V. All rights reserved.Ethnopharmacological relevance: The management of diabetes mellitus management in African communities, especially in Gabon, is not well established as more than 60% of population rely on traditional treatments as primary healthcare. The aim of this review was to collect and present the scientific evidence for the use of medicinal plants that are in currect by Gabonese traditional healers to manage diabetes or hyperglycaemia based here on the pharmacological and toxicological profiles of plants with anti-diabetic activity. There are presented in order to promote their therapeutic value, ensure a safer use by population and provide some bases for further study on high potential plants reviewed. Materials and methods: Ethnobotanical studies were sourced using databases such as Online Wiley library, Pubmed, Google Scholar, PROTA, books and unpublished data including Ph.D. and Master thesis, African and Asian journals. Keywords including ‘Diabetes’ ‘Gabon’ ‘Toxicity’ ‘Constituents’ ‘hyperglycaemia’ were used. Results: A total of 69 plants currently used in Gabon with potential anti-diabetic activity have been identified in the literature, all of which have been used in in vivo or in vitro studies. Most of the plants have been studied in human or animal models for their ability to reduce blood glucose, stimulate insulin secretion or inhibit carbohydrates enzymes. Active substances have been identified in 12 out of 69 plants outlined in this review, these include Allium cepa and Tabernanthe iboga. Only eight plants have their active substances tested for anti-diabetic activity and are suitables for further investigation. Toxicological data is scarce and is dose-related to the functional parameters of major organs such as kidney and liver. Conclusion: An in-depth understanding on the pharmacology and toxicology of Gabonese anti-diabetic plants is lacking yet there is a great scope for new treatments. With further research, the use of Gabonese anti-diabetic plants is important to ensure the safety of the diabetic patients in Gabon.Peer reviewedFinal Accepted Versio

Nutritional value, micronutrient and antioxidant capacity of some green leafy vegetables commonly used by southern coastal people of Bangladesh.

Southern coastal people of Bangladesh are highly vulnerable to food insecurity and malnutrition due to coastal flooding, deforestation and increased soil salinity. A number of green leafy vegetables are found in the southern coastal belt being traditionally eaten as daily basis by local people. But they are unaware of nutritional and medicinal use of these vegetables. To contribute to their wider utilization, five common vegetables namely Hibiscus sabdariffa, Trianthema portulacastrum, Diplazium esculentum, Heliotropium indicum L. and Hygrophila auriculata were selected for analysis of nutritional proximate, micronutrients and antioxidant potential. Nutritional properties were analyzed in terms of moisture, pH, protein, lipid, ash, fibre, minerals and carbohydrate. Total flavonoid, tannin and antioxidant capacity were evaluated using established protocols. The results demonstrated that collected plants are rich in carbohydrate, fibre, proteins, moisture and ash content but low in lipid content. The mineral elements were high with remarkable amount of Na (19.9-21.5 mg/gm), K (7.9-13.5 mg/gm) and P (1.0-1.8 mg/gm). All the samples were found to have considerable amount of flavonoid (90.6-144.5 mg QE/gm) and tannin content (26.8-57.2 mg GAE/gm). The IC50 value of DPPH and superoxide radical scavenging was the lowest for H. indicum (37.1 and 83.4 μg/ml, respectively) whereas T. portulacastrum possessed high reducing power (IC50 53.7 μg/ml). Among the five investigated species, T. portulacastrum and H. indicum were found to have good nutritional and antioxidant properties, thus can be promoted as a significant source of nutritional and antioxidant food supplements

Levels of heavy metals in fish obtained from two fishing sites in Akwa Ibom State, Nigeria

No Abstract

MITIGATION OF AMMONIUM CHLORIDE CORROSION ON CARBON STEEL IN REFINING UNIT

Ammonium chloride corrosion produces localized destructive form of corrosion posing devastating threat to refining equipment integrity and safety of refinery process. Ammonium chloride forms an underdeposit corrosion mostly experienced in the overhead equipment and piping for crude and hydroprocessing units causing severe fouling and damages that posed negative impact on the operating reliability of various processing units. This work addresses the corrosion mechanism caused by ammonium chloride and its inhibition against Hydrochloric acid using Carbon steel. Weight loss analysis and polarization was used to study the inhibition efficiency and corrosion rate of the samples in 0.5M HCl, 1.0M HCl, 20% NH4Cl and 30% NH4Cl solution. The average inhibition efficiency and corrosion rate for 0mL, 2mL, 4mL, 6mL, 8mL, and 10mL of Neem Oil in 0.5M HCl, 1.0M HCl, 20% NH4Cl, and 30% NH4Cl solutions were determined. Result showed that Neem Oil Extract was effective in both HCl and NH4Cl solution on Carbon steel. Inhibition efficiency of each samples increases with Neem Oil concentration while the corrosion rate decreases with concentration

Phytochemical Screening and Effect of Ethanol Root Extract of Microdesmis Puberula on Some Haematological and Biochemical Parameters in Normal Male Albino Wistar Rat

Abstract: Microdesmis puberula Hook f. ex. Planch (Pandaceae) is one of the understudied medicinal plants whose pharmacological properties are beginning to be elucidated. In the present study, ethanol root extract of M. puberula was used to assess its effects on some biochemical and haematological parameters. The root extract was administered in graded doses of 200, 400 and 600 mg/Kg body weight to groups II, III and IV respectively while the control group received 1ml of Tween 80 solution. Phytochemical screening of the extract revealed the presence of saponins, cardiac glycosides, deoxysugars, alkaloids and terpenes. The results of acute toxicity study showed that the extract has a wide margin of safety. The extract did not exhibit any significant effects (p>0.05) on haematological parameters such as PCV, Hb, MCV, MCHC and RBC count. ALT and AST did not show any significant difference (p>0.05) between control and treatment groups. There was a significant (p<0.05) increase in serum cholesterol, LDL-C, TGs and significant (p<0.05) decreased HDL-cholesterol as a consequence of the administration of this extract. Generally, the results indicate that there were no serious adverse effects associated with the use of this extract except in the case of lipid profile studies

CHEMICAL AND NUTRITIONAL EVALUATION OF THE RAW SEEDS OF MACROTYLOMA CHRYSANTHUM

The paper presents chemical and nutritional information on the underutilised seeds of M. chrysanthum. Chemical analyses show that the seeds are not rich in lipids and hence have a low energy value. The seeds were found to be rich in some essential amino acids (especially lysine), macroelements (Na, K, Mg) and ascorbic acid. The antinutrient levels of tannin, phytic acid and hydrogen cyanide were found to be low hence the seeds could be considered to be nutritionally good

Comparative studies on nutrient and antinutrient composition of Eremomastax polysperma (Benth.) Dandy varieties in Akwa Ibom State, Nigeria Iba, Innocent Udofia

Abstract The varieties of Eremomastax polysperma investigated for the presence of nutrient and anti-nutrient. Standard analytical methods were used for these analyses. The varieties possessed high moisture content with Eremomastax polysperma purple leaf bark (EP) (81.90±3.28 %) being higher than the 79.13±1.57 % contained in the EG variety. There is a similar trend in the various aspects of the proximate composition of the plant, except the ash and fibre contents which were significantly different at p < 0.05 confidence level. Generally, the plants are rich in all the classes of nutrient. The presence of phytochemicals in these plant species suggests a possibility of medicinal usage of these plants. Tannins are present in the range of 52.23 ± 1.43 -62.33 ± 2.75 mg/100g with EP exhibiting a higher level than the Eremomastax polysperma green leaf bark (EG) variety, there is a high level of phenols in both varieties with EG having a higher level than the EP sample. Alkaloids and saponins are also present in the ranges of 2.94±0.05 -3.65±0.05 and 4.19±0.16 -4.28±0.02 respectively. EP has a higher level of alkaloid while EG had higher levels of saponins. There were significant differences in zinc (Zn), magnesium (Mg) and calcium (Ca) contents of the two varieties. These sources of local plants could be a good source of trace elements essential to man. Despite the presence of useful nutrients in the plant varieties, there is likely to be safety concerns on the consumption of these botanicals due to the presence of antinutrients such as oxalate, thiocyanide and phytate

CAGW Peptide Modified Biodegradable Cationic Copolymer for Effective Gene Delivery

In recent years, gene therapy has become a promising technology to enhance endothelialization of artificial vascular grafts. The ideal gene therapy requires a gene carrier with low cytotoxicity and high transfection efficiency. In this paper, we prepared a biodegradable cationic copolymer poly(d,l-lactide-co-glycolide)-graft-PEI (PLGA-g-PEI), grafted Cys-Ala-Gly-Trp (CAGW) peptide onto this copolymer via the thiol-ene Click-reaction, and then prepared micelles by a self-assembly method. pEGFP-ZNF580 plasmids (pDNA) were condensed by these micelles via electrostatic interaction to form gene complexes. The CAGW peptide enables these gene complexes with special recognition for endothelial cells, which could enhance their transfection. As a gene carrier system, the PLGA-g-PEI-g-CAGW/pDNA gene complexes were evaluated and the results showed that they had suitable diameter and zeta potential for cellular uptake, and exhibited low cytotoxicity and high transfection efficiency for EA.hy926 cells