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A study was carried out to identify lactic acid bacteria (LAB) isolated from chibuku that would be later assessed for potential as starter cultures. Thirty-eight isolates were Gram stained and the 20, which were Gram positive, were identified to genus level using morphological, physiological and biochemical tests. Five genera of lactic acid bacteria were identified and these were Lactobacillus (seven isolates coded B1, B2, C4, E3, E6, F1 and F4), http://www.bioline.org.br/request?ft02022 (1 of 10)9/18/2004 6:59:06 AM http://www.bioline.org.br/request?ft02022Lactococcus (five isolates: E1, F5, G5, G6 and H1), Leuconostoc (three isolates: E2, D5, F6), Streptococcus (two isolates: G2 and G4) and Enterococcus (three isolates: B3, B4 and G3).From these genera, eleven isolates five from the genus Lactobacillus, three from Lactococcus and three from Leuconostoc were selected for identification to species level using API 50 CH kits. The Lactobacillus strains were identified as follows: two strains were Lb plantarum (C4 and F4), two strains Lb. delbrueckii (B2 and E3), one strain could not be assigned to a species and was termed Lactobacillus sp. E6. Two of the Lactococcus isolates were identified as Lc. lactis subsp. lactis (G6 and H1), while the third isolate was Lc. raffinolactis (strain F5). The three Leuconostoc strains were Ln. mesenteroides subsp. mesenteroides.

This work reports the use of metallo tetra-amino phthalocyanines (MTAPc, M = Co and Mn) polymer thin films on gold and glassy carbon electrode surfaces for the detection and monitoring of hydrogen peroxide (H 2 O 2 ). The polymer-modified electrodes were characterized using electrochemical and microscopic-based methods. Atomic force microscopy (AFM) was used to study the bare and polymermodified ITO surfaces. The electrocatalytic reduction of H 2 O 2 with glassy carbon polymer-modified electrodes gave higher current densities compared to their gold counterparts. The electroanalytical properties of H 2 O 2 were obtained using a real-time calibration curve of the amperometric determination in pH 7.4 aqueous solution. The limits of detection (LoD) of the polymer-modified electrodes towards electroreduction of H 2 O 2 were of the order of 10 -7 M, with high sensitivity ranging from 6.0-15.4 mA.mM -1 .cm -2 .APPlICAtIOnS Of POlymerIzeD metAl tetrA-AmInO PhthAlOCyA nIneS 253MPc-modified electrodes are their ability to form stable polymers on electrode surfaces [6-13, 24] and long shelflife. We have previously reported [4] on the use of CoPc derivative-modified gold electrodes using self-assembly monolayer method (SAM) for the detection and monitoring of H 2 O 2 with detection limits of 1 × 10 -7 M and a reduction potential of -0.2 V vs. Ag|AgCl. SAMs on gold electrodes desorbs from the electrode at high pH, allowing only narrow potential range to be used [21]. CoPc-, MnPc-and FePc-modified screen-printed carbon electrodes (SPCE) have been employed for the detection of hydrogen peroxide with electrochemical reduction potential of -0.35 V vs. Ag|AgCl [20]. There is a need to lower both the detection limit and reduction potential for hydrogen peroxide without the use of unstable enzyme electrodes. The MPc complexes studied in this work contain cobalt and manganese as metal ion centers and these complexes are known to exhibit excellent electrocatalytic activity [25][26][27][28][29][30]. The amino functionalities on the phthalocyanine macrocycle were chosen due to their known ease of forming polymers on electrode surfaces [12,13,24], which are more stable for analysis compared to SAMs. The electrocatalytic and electroanalytical properties of gold and glassy carbon electrodes modified with thin polymeric films of CoTAPc and MnTAPc are compared for electroreduction of H 2 O 2 .

Plastic bag waste is a major challenge in several African countries. As a way of reducing the detrimental effects posed by plastic bags, governments have adopted various approaches for plastic bag waste management that include levies, bans and or the combination of the two. Despite the adoption of anti-plastic bag policies in several African countries, there has been limited investigation regarding their effectiveness. Thus, the present paper reviews the effectiveness of legal and policy framework approaches for plastic bag waste management in African countries. This systematic review covers legal and policy framework approaches for plastic bag waste management in African countries since 2004 with a view to find their effectiveness. Data sources included peer-reviewed journal articles, websites, books, reports, and dissertations. The databases from which literature was retrieved included Elsevier, Taylor, Springer, institutional repository, and Google Scholar. The current paper argues that poorly enforced plastic bag legislation, resistance from stakeholders, and limited effective substitutes are major factors hindering effective plastic bag waste management in Africa. A six-step model developed by Patton and Sawicki assisted in evaluating plastic bag policies in varied African nations. The study concluded that the key to effective legislation is hinged on consistent enforcement and educating the public to attain environmental buy-in. African countries should adopt and implement the Patton and Sawicki six-step rationalist model to achieve effective plastic bag legislation. African governments should enlighten consumers about other alternatives that are more specific to African countries, especially bags made of raffia and leaves. The findings are limited in that there may be other relevant articles (beyond published articles) about policy and legal approaches for plastic bag waste management, which are not available in the public domain. Therefore, data reviewed may not be exhaustible.