Scientect Journal of Life Sciences

Screening, isolation and characterization of lactic acid bacteria strains in fermenting cocoa heaps from the Eastern Region of Ghana

2017-03-18T12:57:00+0530

Cocoa fermentation is the primary process of producing quality chocolate taste and flavour. Lactic acid bacteria (LAB) are one of the key microorganisms in this heterogeneous fermentation process. They break down the sugars and citric acid in the cocoa pulp to produce lactic acid, acetic acid, and mannitol that influence the quality of the fermented bean. LAB strains as monoculture or co-culture could be an essential component of starter culture aimed at the control of cocoa bean fermentation process. This study screened, isolated and characterized LAB strains in cocoa heap fermentation to compare the amount of lactic acid produced by the various strains. Cocoa beans were fermented and enumeration of microorganisms was carried out. Microbial colonies were randomly selected and subcultured on MRS medium. Pure isolates were screened for LAB by carrying out catalase test and gram reaction. The isolated pure LAB strains were subjected to morphological, physiological and biochemical characterization. The amounts of lactic acid produced by the various strains were determined. There were two presumptive Lactococcus species as well as two presumptive Lactobacillus species. Different NaCl concentrations as well as citrate hydrolysis test were used to subdivide both species. C16 was identified to be presumptive Lactobacillus fermentum, C17 was identified to be Lactococcus lactis subsp. cremoris, C20 was identified to be presumptive Lactobacillus brevis and C23 was identified to be Lactococcus lactis subsp. lactis biovar diacetylactis. Lactococcus lactis subsp. cremoris produced the highest amount of lactic acid (185g lactic acid / L of culture medium) with Lactococcus lactis subsp. lactis biovar diacetylactis producing the least amount of lactic acid (95g lactic acid / L of culture medium). The above presumptive LAB species especially one with the highest amount of lactic acid produced could be a potential strain in producing a starter culture for a controlled cocoa fermentation.

The use of wavelength dispersive x-ray fluorescence (WDXRF) spectrometry and multivariate techniques for assessment of illegal dyes in spices

2017-07-14T00:09:13+0530

Sudan dyes are carcinogenic azo and diazo compounds that are banned for use in food worldwide including the European Community. The ability of WDXRF spectroscopic technique to predict the types and levels of adulteration of spices suspected to be adulterated with Sudan I-IV, Para Red and Sunset Yellow dyes was investigated. Logistic regression and discriminant analysis classification models were developed to predict the type of adulteration using WDXRF spectral features. Prediction of the levels of adulteration was assessed by using multiple regression analysis. 83% of the 210 adulterated samples were correctly classified by the logistic regression with 90% sensitivity, 75% specificity with a prediction power of 92% into respective adulteration groups. 86% and 90% correct prediction were obtained for discriminant analysis models with 94% sensitivity and 74% specificity. Three multiple regression models were performed for each data set. The full model based on both the Compton and Rayleigh ratios as well as the Compton and Rayleigh scatter intensities revealed to be the best model to predict the levels of adulteration with an adjusted R² between 95.1 to 99.0% with errors of estimate between 1.6 to 3.7%. WDXRF technique may represent a promising tool for the screening of Sudan dyes-adulterated spices and can be used as an alternative to classical methods for the determination of Sudan dyes present in food prior to confirmation with more sensitive chromatographic-based methods.

Scientific basis of the combination of Coca-Cola drink and tomato paste in the management of anaemia

2017-09-28T16:53:47+0530

Anaemia is a global health problem affecting people of all works of life. Anaemia has a lot of adverse effects hence the need for a cost-effective and better treatment strategy. Ethnopharmacological information indicates the use of the combination of Coca-Cola drink and tomato paste to manage anaemia in Ghana. The study investigated the effect of the combination of Coca-Cola drink and tomato paste on haemoglobin levels using animal models. 20 male Wistar rats were grouped as normal, 2,4-DNPH only, Coca-Cola drink only (0.5 ml Coca-Cola drink/100 gm b. wt./day), tomato paste only (20 mg tomato paste/100 gm b. wt./day) and combination of Coca-Cola drink and tomato paste (0.5 ml Coca-Cola drink/100 gm b. wt./day and 20 mg tomato paste/100 gm b. wt./day) with 4 animals in each group. Animals in other groups apart from the normal group were injected with 2,4-DNPH consecutively for 7 days (2 mg/100 gm w.bt/day i.p,). Animals in 2,4-DNPH only group were sacrificed on the 8^th day. All animals in the remaining groups were maintained till the 21^st day. Body weight was significantly reduced (p˂0.05) in all groups with 2,4-DNPH injection in the first 7 days. From the 8^th-21^st day, body weight was significantly gained (p˂0.05) in the combination of Coca-Cola drink and tomato paste group. Haemoglobin concentration, red blood cell count and packed cell volume were not significantly reduced in the 2,4-DNPH only group. However, haemoglobin concentration, red blood cell count and packed cell volume were significantly increased (p˂0.05) in the tomato paste only group and in the combination of Coca-Cola drink and tomato paste group. Conclusively, a combination of Coca-Cola drink and tomato paste had a significant increase on the haemoglobin levels indicating some haematinic and anti-anaemic potential.

Immune checkpoint inhibitors for non-small cell lung cancer – review

2017-10-21T20:00:57+0530

The aim of this review was to evaluate the efficacy of immune checkpoint inhibitors (ICIs) for non-small cell lung cancer (NSCLC). NSCLC is the most common lung malignancy (85% of all lung cancers) and has a poor prognosis. Though chemotherapy is an effective therapeutic option, factors such as drug resistance, drug toxicity, and adverse side-effects cause poor response rate and ~10-20% survival within 2 years in metastatic NSCLC patients. The efficacy of ICIs in NSCLC has been widely studied as an alternative treatment option. This review discusses the role of ICIs in tumorigenesis, recent clinical trials, clinically available ICIs, including their efficacy, toxicity, and application as a single agent and in combination with other agents. Currently, ICIs such as Nivolumab and Pembrolizumab have been approved as effective therapeutic options for NSCLC. Durable response rate, improved overall survival, and tolerable safety profiles have been recorded in clinical trials for these ICIs. Combination treatments with ICIs such as Nivolumab + Ipilimumab and Durvalumab + Tremelimumab have been shown in clinical trials to provide better safety and efficacy profiles than single ICI treatment. However, further research is required to study different ICI combination therapies in treating metastatic NSCLC and variations in efficacy among smokers and non-smokers. It is recommended that future research should consider combination therapy with other conventional therapies including chemotherapy, radiotherapy, and personalized targeted therapy; the efficacy of ICIs for early-stage cancer; and identification of predictive biomarkers.

Exercise immunology: involved components and varieties in different types of physical exercise

2017-11-05T14:46:20+0530

Physical exercise induces modifications in the immune system influencing either positively or negatively on health depending on its frequency, duration, and intensity. Acute or moderate physical exercise increases appreciably the immune cells, including cytokine levels while decreasing other components like NK cells, leading to a stronger response to pathogens as well as decreasing liability to allergic reactions. The expression of Toll-like receptors (TLR) is elevated as well, augmenting the positive effect. Exhaustive physical exercise, by contrast, modifies the immune system adversely. This review explores the links between physical exercise, immune cells and cytokines, and the immunological effects that have been studied by the performance of different kinds of physical exercise.