Browsing by Author "Senanayake, C."

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    Determination of Antioxidant and Antimicrobial Activities of Psidium guineense Sw. Leaf Extracts Fractioned Based on Polarity
    (19th Conference on Postgraduate Research, International Postgraduate Research Conference 2018, Faculty of Graduate Studies,University of Kelaniya, Sri Lanka, 2018) Munaweera, R.R.K.W.; Senanayake, C.; Algama, H.; Seneviratne, K.; Jayathilaka, N.
    Psidium guineense Sw. is a guava species distributed in South America, some parts of Africa and South Asia including Sri Lanka. Our previous studies have shown that Psidium guineense Sw. leaves contain 195.25±9.56 mg g-1 phenolic substances and 70 % ethanolic extract of P. guineense Sw. Leaves (PGLE) improve the oxidative stability and microbial shelf life of vanilla cake. PGLE may contain highly polar as well as medium and low polar phenolic substances. Therefore, antioxidant activity and antimicrobial activity of the further fractionated portions by chloroform and hexane of PGLE on food spoilage bacteria were determined. For this purpose, PGLE was obtained by solvent extraction and solvents of PGLE and different fractions were evaporated and reconstituted in 10 % ethanol. The antioxidant activities of solvent fractions, BHT and PGLE measured using DPPH radical scavenging assay are given in Figure 1. Figure 1. DPPH radical scavenging activity The antimicrobial activities of PGLE, chloroform fraction of PGLE and hexane fraction of PGLE were determined using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay for four microbial strains, two gram negative; Escherichia coli and Salmonella typhimurium and two gram positive; Bacillus cereus and Staphylococcus aureus. Ethanol from the extracts was maintained at 1% in the antimicrobial assays. PGLE showed the higher antimicrobial activity towards gram positive bacteria with LD50 values of 190.4 ± 20.2 mg/L for Staphylococcus aureus and 305.4 ± 22.4 mg/L for Bacillus cereus than gram negative bacteria with LD50 of 444.9 ± 13.0 mg/L for Escherichia coli and 508.6 ± 64.7 mg/L for Salmonella typhi. Streptomycin and chloramphenicol were used as positive controls. No antimicrobial activity was observed for chloroform and hexane fractions of PGLE in the four bacterial strains tested. The results of the present study suggest that phenolic compounds with medium polarity may be mainly responsible for antioxidant activity while phenolic compounds with high polarity may be responsible for antimicrobial activity.
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    Phoolan Devi and Kuveni –“Bandit Queen” and “Queen of the Yaksha” – “Queens” or Gendered Subalterns?
    (University of Kelaniya, 2012) Senanayake, C.
    Phoolan Devi, as depicted in Mala Sen’s biographical India’s Bandit Queen and in Shekhar Kapur’s cinematic representation The Bandit Queen, as well as Kuveni, as depicted in SugathSamarakoon’s film Vijaya Kuveni and in Henry Jayasena’s theatrical production Kuveni, are ideal examples of the “gendered subaltern” figure that Gayatri Chakravorty Spivak discusses in her seminal article, “Can the Subaltern Speak?”. However, these female figures do not passively accept the oppression they are subjected to. They resort to alternative means of resistance that may go against accepted social norms. Phoolan Devi joins a gang of dacoits and commits various illegal acts. Kuveni challenges the patriarchal system that kept her in a subjugated position by allying herself with a group of foreign invaders headed by Prince Vijaya. On the other hand, one can question this supposed resistance and challenging of patriarchy. Can the gendered subaltern ever “speak” anything but the language of patriarchy? Is there space for a truly “female” voice? Such questions finally bring us to the problem of “representation” and “representation”, forcing us to ask who has the authority to represent whom? In this research, the focus is to look at these issues in relation to the figures of Phoolan Devi and Kuveni as represented in the abovementioned texts. As Spivak states in the concluding lines of her essay, “The subaltern cannot speak”. This can be seen in relation to the figures of Phoolan Devi and Kuveni as represented by Mala Sen and Shekhar Kapur, and Henry Jayasena and SugathSamarakoon respectively. The reason behind this inability to “speak” lies in problems of representation. Even on occasions when the gendered subaltern “speaks”, it is tainted by the voice of patriarchy. Therefore, one must attempt to locate a space in which the gendered subaltern can speak her own voice, unencumbered by her male counterparts.