A synchronic analysis of Indian English

The present paper aims at exploring the impact that linguistic background can have on individual speech. After a brief review on how English became an official language in the republic of India, I will concentrate on the phonological aspect of Indian English. I will, firstly, procure a framework that ensures a baseline for a standard form of Indian English. Secondly, I will analyse an authentic speech sample and will discuss a number of factors that account for the adherence/deviation from the standard and which depict the phonological identity of this particular speaker

The diversity of antifungal compounds of six South African Terminalia species (Combretaceae) determined by bioautography

A bioautography method was developed to determine the number of antifungal compounds in Terminalia species extracts. Acetone, hexane, dichloromethane and methanol leaf extracts of six Terminalia species (T. prunioides, T. brachystemma, T. sericea, T. gazensis, T. mollis and T.sambesiaca) were tested against five fungal animal pathogens (Candida albicans, Cryptococcus neoformans, Aspergillus fumigatus, Microsporum canis and Sporothrix schenkii). The Rf values and relative activities of separated compounds were determined. Hexane and dichloromethane extracts had at least three times more antifungal compounds than the other extracts indicating the nonpolar character of the antifungal compounds. From the Rf values, the non-polar character of the antifungal compounds was confirmed indicating that the antifungal activity is not due to tannins. M. canis had the highest number, up to ten, of antifungal compounds. All Terminalia species contained a compound (Rf =0.46 in benzene/ethanol/ammonium hydroxide (90/10/1) active against all tested pathogens. T. sericea and T. brachystemma were the most promising candidates for isolating antifungal compounds. The results demonstrate the value of bioautography in examining plant extracts with antifungal activity,selecting species for further study and dereplicating the isolation of compounds

Bioautography indicates the multiplicity of antifungal compounds from twenty-four southern African Combretum species (Combretaceae)

Dried ground leaves of 24 Combretum spp were extracted with hexane, dichloromethane, acetone and methanol and analysed by bioautography to determine the number of antifungal compounds againstfive animal fungal pathogens (Candida albicans, Cryptococcus neoformans, Aspergillus fumigatus, Microsporum canis and Sporothrix schenckii). There was some similarity in the chemical compositionof the non-polar components of extracts using extractants of varying polarity. Acetone extracted the most antifungal compounds from Combretum spp. Combretum spp. in the section Hypocrateropsis, C.celastroides ssp. celastroides and C. clelastroides ssp. orientale had 62 different antifungal zones of inhibition compared to the 7 to 8 of C. microphyllum and C. paniculatum in the Connivetaia section. C.collinum subspecies were not active against all the tested pathogens. C. neoformans was the most sensitive organism against all Combretum species, with 367 zones of inhibition using different TLCsolvent systems and extracts. A. fumigatus was the most resistant (192 zones of inhibition). The antifungal activity and number of active antifungal compounds were high enough to consider the use ofextracts for clinical application and to isolate antifungal compounds from the extracts. Based on the Rf values of the antifungal compounds determined using solvents of varying polarity, activity is not onlybe attributable to tannins found in Combretum extracts as was previously postulated

Characterization of antifungal compounds isolated from Combretum and Terminalia species (Combretaceae)

Several investigations into the antimicrobial activity of members of the Combretaceae have been undertaken in recent years. Although the antibacterial properties of various species of Combretum, Terminalia and Pteleopsis have been investigated in depth, this is not the case for their antifungal properties. Due to the increasing importance of fungal infections the aim is to address this by focusing on antifungal activities of Combretaceae species. This was done by focusing on the following objectives: Developing minimum inhibitory concentration (MIC) and bioautography procedures for fungi to be used in the laboratory in order to screen Combretum andTerminalia species for antifungal activity. Selecting three or four species for further investigation based on antifungal activity and availability. Isolating the antifungal compounds from one or more of the selected species. Determining the chemical structure and in vitro biological activity of the antifungal compound. Developing and applying a protocol and determining in vivo antifungal activity of Combretum and Terminalia extracts and isolated compounds in rats infected with different fungal pathogens. Leaves of 24 Combretum and 6 Terminaliaspecies were collected in the Lowveld National Botanical Gardens (LNBG) in Nelspruit. After the dried plants were milled to a fine powder, they were extracted with hexane, dichloromethane, acetone and methanol. Chemical constituents of the 120 extracts were analyzed by thin layer chromatography (TLC). The TLC plates were developed with one of the three eluent systems developed in our laboratory that separate components of Combretaceae extracts well i.e.: Ethyl acetate/methanol/water (40:5.4:5) [EMW] (polar/neutral), Chloroform/ethyl acetate/formic acid (5:4:1) [CEF] (intermediate polarity/acidic) and Benzene/ethanol/ammonia hydroxide (90:10:1) [BEA] (non-polar/basic). To detect the separated compounds, vanillin-sulphuric acid-methanol was sprayed on the chromatograms and heated at 110 °C to optimal colour development. Methanol was the best extractant, extracting a greater quantity of plant material than any of the other solvents. There was similarity in the chemical composition of the non-polar compounds of extracts using extractants of varying polarity Qualitative analysis of antioxidant activity, the 2, 2,diphenyl-1-picrylhydrazyl (DPPH) assay on TLC plates was used as a screen test for the radical scavenging ability of the compounds present in the different 120 extracts. TLC-DPPH screening method indicated the presence of antioxidant compounds in some of the extracts tested, with C. woodii and C. hereroense showing the most prominent antioxidant activity. Methanol and acetone extracted the most antioxidant compounds based on DPPH TLC. In vitro studies coupled with the phytochemical analysis confirm that the extracts had antioxidant activity. The solvent tolerance of the microorganisms was tested using the following solvents; DMSO, acetone, methanol and ethanol. In order to determine the maximum concentration at which different solvents would allow the test microorganisms to reach normal growth, different concentrations from 10 to 100% were used. Uninhibited growth was evaluated as no toxic effects of the solvent. Methanol and ethanol were found to be toxic. The growths of the fungi were not affected by DMSO and acetone concentrations up to 60%. A serial microdilution assay was used to determine the minimum inhibitory concentration (MIC) values for plant extracts using tetrazolium violet reduction as an indicator of growth. This method had previously been used only for antibacterial activities. To apply it to measuring antifungal activities, a slight modification was made to suit fungal growth conditions. The following fungal pathogens were used: yeasts (Candida albicans and Cryptococcus neoformans), thermally dimorphic fungi (Sporothrix schenckii) and moulds (Aspergillus fumigatus and Microsporum canis). To determine MIC values, growth was checked after 24 and 48 hours to determine the end point. The MIC values of most of the extracts were in the order of 0.08 mg/ml and some had values as low as 0.02 – 0.04 mg/ml after 24 hours incubation. TLC plates were loaded with 100 ㎍ (5 ㎕ of 20 mg/ml) of each of the extracts. The prepared plates were developed in the three different mobile systems used: CEF, BEA and EMW. The chromatograms were dried for a week at room temperature under a stream of air to remove the remaining solvent. The TLC plates developed were inoculated with a fine spray of the concentrated suspension containing approximately 109 organisms per ml of actively growing fungi e.g. conidia for A. fumigatus and yeast cells (blastocysts) for the other fungi in a Biosafety Class II cabinet (Labotec, SA) cupboard. The plates were sprayed until they were just wet, and after drying were sprayed with a 2 mg/ml solution of INT. White areas indicate where reduction of INT to the coloured formazan did not take place due to the presence of compounds that inhibited the growth of tested fungi. During this study we experienced a number of difficulties. Firstly I found that preparing cultures some days before spraying them makes it difficult to get good results, possibly due to quick mycelial overgrowth and blockage of the spray gun with mycelia. The new method was developed. This procedure led to reduced overgrowth of the mycelia. In the study of biologically active compounds from extracts, it was indicated that the extracts had antifungal compounds. Fractionation and bioassay-guided isolation of the antifungal compounds was undertaken on the crude extracts of C. nelsonii, based on very low MIC’s of the crude extracts on all tested pathogens, it had several compound which are active against all pathogens, lastly it is one of the Combretum species which have never being worked on. Antifungal compound was successfully isolated from the leaves of C. nelsonii. The structure was elucidated. After structure elucidation bioassays of isolated active compounds was done to confirm that the compound isolated is the one expected, and how active the compound is, on its own. The compound was very active against all tested pathogens. Cytotoxicity of the acetone extracts of C. imberbe, C. nelsonii, C. albopunctactum and T. sericea were evaluated using Brine shrimp (Artemia salina assay and tetrazolium-based colorimetric assay (MTT assay) on Vero monkey kidney cells. These four extracts were chosen because of the good in vitro antifungal activity of crude extracts and there was intention of using them in in vivo studies in animal models. The results on brine shrimps indicated that the four leaf extracts have LC50 values above 20 ㎍/ml, the recommended cut-off point for detecting cytotoxic activity. Using MTT assay it was found that the four extracts did not suppress mitochondrial respiration in monkey kidney cells. Only C. imberbe was closer to the cut-off value (200 µg/ml), which was used by other authors. In searching for cytotoxic activity to the criteria of the American National Cancer Institute, the LC50 limit to consider a crude extract promising for further purification is lower than 30 µg/ml. In vivo antifungal activity was investigated on the wound irritancy and efficacy of the four most promising, Combretum nelsonii, Combretum imberbe, Combretum albopunctactum and Terminalia sericea extracts applied topically to skin wounds in fungal infected skin wound of rat model. Wound irritancy and wound healing were evaluated by macroscopical, physical and histological methods. Aspects evaluated include wound healing, erythema, exudate formation and possible toxic effects of the extracts. Twenty rats were used in two pilot studies (Exploratory studies and Infection with different pathogens). During the pilot studies rats were not irritated by treatment of infection. The wound healed within three weeks. Only one rat was terminated due to weight loss and it was found that nasal discharge was due to external factors, which were not related to the experiment. The clinical treatment of skin infected with pathogens continues to be a major problem especially in immuno-compromised patients. Therapeutic agents selected for the treatment of infected wounds had ideally shown antifungal activity on in vitro studies. I investigated whether these agents would improve phases of wound healing without producing deleterious side effects. All the parameters showed that the crude extracts and amphotericin B were effective in decreasing formation of the exudate, increasing crust formation and that they have antifungal activities used in in vivo studies. Acetone extract of leaves of C. nelsonii, C. albopunctactum, C. imberbe and T. sericea possessed remarkable growth inhibitory activities against fungal pathogens. Acetone extracts of leaves and isolated compound demonstrated wound healing properties comparable with that of antibiotic powder (amphotericin B). The results of this study in general indicate that the Terminalia and Combretum species possess substantial antifungal properties. This explains the use of these plants in folk medicine for the treatment of various diseases related to fungal infections.Thesis (PhD (Phytomedicine))--University of Pretoria, 2006.Paraclinical Sciencesunrestricte

Population genetics of Swakara sheep inferred using genome-wide SNP genotyping.

Master of Science in Genetics. University of KwaZulu-Natal, Pietermaritzburg 2015.The pelts of Swakara sheep breed of Namibia are famous for their lustrous features and are unmatched in quality across the globe. These pelts occur in four subpopulations of white, grey, black and brown. The white pelt is the most preferred pelt colour. However, there is a challenge in producing white pelts due to the sub-vital factor that affects homozygous white lambs, thought to be a result of the negative impact of years of inbreeding and selection pressures. Sub-vital performance is a genetic disorder that causes digestive complications in lambs resulting in their death within days of birth. The ability to identify carriers or affected individuals of sub-vital performance at an early stage will save the Swakara industry production costs and reduce mortality rates in the white subpopulation. In this study, high-throughput SNP genotyping was used to perform a population genetics study, which investigates the genetic structure of Swakara with the aim of identifying structural differences between sub-vital individuals and the other coat colours, and by using GWAS to determine the variants contributing to sub-vitality in subtle effects and their associated genes in Swakara. This study will also look at selection pressures in Swakara, the genetic differentiation between subpopulations, level of inbreeding and the presence of ROH segments in Swakara and their associated genes that relate to sub-vital performance. Genetic statistical tools such as PLINK, ARLEQUIN and SVS were used to perform the analyses required for this population study. Ninety Swakara sheep were collected from Namibia and South Africa. These were sub-divided into four colour subpopulations of black (n = 16), grey (n = 22), vital white (n = 35) and sub-vital white (n = 17). The DNA from each of these was then genotyped using the OvineSNP50 beadchip. The genotyping success rate was > 93% across all the colour subpopulations. The quality control (QC) post genotyping was done by removing SNPs that departed from HWE > 0.0001, had low allele frequencies MAF 0.01 and individuals that had missing genotypes (MIND) > 0.1. This QC was done for every subpopulation described in this study prior to all other succeeding analyses. The inbreeding coefficient F was high in the black subpopulation (0.04798±0.069) and lowest in the grey (0.01074±0.079) Swakara sheep. The genetic diversity for the Swakara subpopulations showed a consensus in the results and showed the most diversity between the black and white subpopulations. The PCA results also showed the genetically similar subpopulations, as identified by pairwise FST values, clustered together. Forty-two unique ROH were observed across 10 chromosomes in 33 (out of 90) individuals and spanned between 5198.93-7126.85 KB in length in the four colour subpopulations. The white sub-vital group had the highest number of ROHs (18). Seven overlapping/consensus regions of homozygosity were observed on chromosome 2, 7, 9, 10, and 20. There was no correlation between the frequency of ROHs in an individual and the level of inbreeding, however the black subpopulation had the highest level of inbreeding and had the highest average of ROH length among the other subpopulations but this was not a consistent trend with the other subpopulations. The GWAS revealed at least five SNPs associated to sub-vitality located on chromosome 3, 5, and 8. Chromosome 3 had three different SNPs associated to sub-vitality. The most prominent SNPs was located on chromosome 3, which is associated to a gene, IGF1, responsible for insulin-like growth factor and contributes to the development of foetal organs. The genes identified by GWAS and cROH pointed to the cause of sub-vitality due to the contributing effects of biological functions related to metabolic activities. A targeted gene sequencing study would be required to assess the differences in the sequences of the identified significant SNPs, the IGF1 genetic region, in order to examine the possible causal mutations of sub-vitality. A study focussed more on the white and sub-vital subpopulation, with an increased sample size and a targeted gene sequencing approach would assess the differences in the targeted sequences of both case and control individuals

The phytochemical, antibacterial and antioxidant activity of five medicinal plants against the wound infecting bacteria

Leaf extracts of Senna italica, Ricinus communis, Lantana camara, Lippia javanica and Ziziphus  mucronata were screened for biological activity against bacteria which infect wounds. The leaves were extracted using different solvents of varying polarity (hexane, dichloromethane, acetone and methanol). Phytochemical analyses of the extracts were performed using thin layer chromatography (TLC). The extracts were loaded on TLC plates and developed in three solvent systems that is benzene/ethanol /ammonium solution (BEA), chloroform/ethyl acetate/formic acid (CEF) and ethyl acetate/methanol /water (EMW). Antibacterial activity of the plants was evaluated using micro-dilution and bioautography methods. The test organisms used were Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis. Acetone extracts were chosen for antioxidant activity. Methanol was the best extractant, followed by acetone and dichloromethane (DCM). In the phytochemical analysis,  more compounds were observed on BEA, followed by EMW and CEF plates. Lantana camara had no  activity against any of the bacteria used. P. aeruginosa was the most resistant bacterium with only two plants active against it. E. faecalis and E. coli were sensitive to the extracts. More antibacterial  compounds were observed on BEA plates against all the test bacteria in bioautographic method. The Rf  values calculated from bioautography indicated that the selected plants have different active compounds. The most active compounds were from S. italica and Z. mucronata. BEA and EMW plates had good  antioxidant activity. No antioxidant activity was observed on the CEF plate. Most extracts were active against wound pathogens; their application on the wound area may prevent infection. Further studies are required to identify the active compounds in the plant extracts which showed significant anti-bacterial activities.Key words: Thin layer chromatography (TLC), plant extract, bacteria

A synchronic analysis of Indian English

The present paper aims at exploring the impact that linguistic background can have on individual speech. After a brief review on how English became an official language in the republic of India, I will concentrate on the phonological aspect of Indian English. I will, firstly, procure a framework that ensures a baseline for a standard form of Indian English. Secondly, I will analyse an authentic speech sample and will discuss a number of factors that account for the adherence/deviation from the standard and which depict the phonological identity of this particular speaker

ANTIOXIDANT AND ANTIBACTERIAL PROPERTIES OF ZIZIPHUS MUCRONATA AND RICINUS COMMUNIS LEAVES EXTRACTS

Background: Plants have always been a successful source of remedy from nature. With the widespread use of medicinal plants by indigenous people, the search for biologically active agents is relevant as these plants have the potential to provide pharmacologically active compounds. This study aimed for investigating the effect of antioxidant and antibacterial properties of Ziziphus mucronata Willd (Rhamnaceae) and Ricinus communis L. (Euphorbiaceae). Materials and methods: Antibacterial activity was evaluated using microdilution assay and bioautography. Antioxidant activities were determined by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH). In vitro cytotoxicity was determined using the tetrazolium-based colorimetric assay. Results: R. communis leaves had eight secondary metabolites. Quantitative assay for R. communis, chloroform and methanol extracts had very high antioxidant activity compared to vitamin C. Plants extracts from all solvents exhibited high antibacterial activity against Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa with minimum inhibitory concentration (MIC) values between 0.21 and 1.05 mg/ml. Most of the antibacterial compounds observed on bioautography had Rf values ranging from 0.21 to 0.88. Z. mucronata had LC50 of 105.5 μg/ml and R. communis 131.8 μg/ml on Vero cells. Conclusion: This study revealed that both plants had free radical scavenging and antibacterial activities

Does seasonal variation influence the phytochemical and antibacterial properties of Carpobrotus edulis?

Carpobrotus edulis L. (family Aizoaceae) has been used by locals over the years to treat microbial infections. Extracts of varying polarities were prepared from the leaf debris and filtrate of a spring andan autumn harvest of C. edulis. Thin layer chromatography was used to analyze the phytocompounds of the extracts as well as to assay the plant for antioxidant compounds. The spring harvest showedequal distribution of the phytochemicals within the leaf debris and the filtrate, but there was a high prevalence of phytocompounds within the leaf debris extracts of the autumn sample. An antioxidantcompound was intensely pronounced in the autumn extracts of intermediate polarity and in the polar extract. The plant was evaluated for antibacterial activity against Escherichia coli, Enterococcusfaecalis, Pseudomonas aeruginosa and Staphylococcus aureus by using a two-fold serial microdilution method as well as bioautography. The spring extracts were more potent against all test organisms,having MIC values that were lower than the autumn extracts. When taking the total activity of each extract into account, the autumn extracts showed higher efficacy than the extracts from the springsample. The antibacterial activity observed in the extracts of both seasons somewhat validated the ethnomedicinal use of C. edulis