1.Antimicrobial activity of certain fresh water microalgae from Thamirabarani River, Tamil Nadu, South India
Prakash Wilfred Justella ; MarimuthuAntonisamy Johnson ; Jeeva Solomon
Asian Pacific Journal of Tropical Biomedicine 2011;(z2):170-173
Objective:To evaluate the antimicrobial potential of fresh water microalgae viz., Oscillatoria sancta (O. sancta) (Kuetz) Gomont., Lyngbya birgei (L. birgei) Smith G.M., Oedogonium echinospermum (O. echinospermum), Spirogyra decimina (S. decimina) (Muller) Kuetz., Spirogyra grantiana (S. grantiana) Transeau., Spirogyra crassa (S. crassa), Spirogyra biformis (S. biformis) Jao. and Spirogyra condensata (Vaucher) Kuetz against human bacterial pathogens. Methods:Antimicrobial study was carried out by disc diffusion method against the pathogens viz., Escherichia coli (E. coli) (ATCC 35218), Staphylococcus aureus (S. aureus) (ATCC 6538), Salmonella typhi (S. typhi) (MTCC 733), Proteus vulgaris (P. vulgaris), Proteus mirabilis (P. mirabilis) and Streptococcus pyogenes. Results: The methanolic extract of O. sancta showed the antibacterial activity against three pathogens viz., P. mirabilis, P. vulgaris and S. aureus with the inhibition zones of 10, 8 and 8 mm, respectively. The methanolic and ethanolic extracts of L. birgei exhibited the antibacterial activity against two pathogens i.e. P. mirabilis and P. vulgaris with the maximum zone of inhibition of 8 and 8 mm, respectively. The ethanolic extracts of O. echinospermum displayed the antibacterial activity against S. typhi and P. mirabilis with the maximum of zone of inhibition (7 mm). The methanolic extracts of S. decimina exhibited the antibacterial activity against S. aureus and P. mirabilis with the maximum zone of inhibition of 12 and 9 mm, respectively. The ethanolic extracts of S. grantiana showed the anti-bacterial activity against three organisms i.e. E. coli, P. vulgaris and P. mirabilis with the zone of inhibition of 9, 10 and 9 mm, respectively. The methanolic extracts of S. crassa exhibited the antibacterial activity against P. mirabilis with the maximum zone of inhibition (9 mm). The methanolic extracts of S. biformis exhibited the antibacterial activity against P. vulgaris with the maximum zone of inhibition (8 mm). Conclusions: These results give an indication of the presence of promising antibacterial compounds in the plants under studied. Further phytochemical studies are needed to elucidate the components responsible for antibacterial activity of these extracts against bacteria.
2.In vitro anti- bacterial activity of leaves extracts of Albizia lebbeck Benth against some selected pathogens
Bobby Nazneen Mohammed ; Wesely Gnanaraj Edward ; Johnson MarimuthuAntonisamy
Asian Pacific Journal of Tropical Biomedicine 2012;(z2):859-862
Objective: To screen the anti-bacterial activity of Albizia lebbeck (A. lebbeck) Benth leaves extract against the selected bacterial pathogens viz., Bacillus subtilis (MTCC441), Escherichia coli (MTCC443), Klebsiella pneumonia (MTCC 109), Proteus vulgaris (MTCC742), Pseudomonas aeruginosa (MTCC741), Salmonella typhii (MTCC733) and Staphylococus aureus (MTCC96).Methods:The leaves extracts of A. lebbeck was tested against bacteria by the agar disc diffusion method. Results: Results of the present study indicated that different extracts of A. lebbeck showed inhibitory effects against the pathogens. The present study results demonstrated that methanolic extracts of A. lebbeck conferred the widest spectrum activities that inhibited the growth of all studied pathogens with the maximum zone of inhibition. The methanolic extracts ofA. lebbeck illustrated the highest zone of inhibition against the pathogens Bacillus subtilis (16 mm), Escherichia coli (22 mm), Klebsiella pneumonia (11 mm), Proteus vulgaris (18 mm), Pseudomonas aeruginosa (22 mm), Salmonella typhii (23 mm) and Staphylococus aureus (17 mm). The ethyl acetate extracts demonstrated maximum zone of inhibition against Escherichia coli (26 mm), Pseudomonas aeruginosa (22 mm) and Klebsiella pneumonia (16 mm). Conclusions: It is expected that this study would direct to the establishment of some active compounds that could be used to formulate new and more potent anti-bacterial drugs of natural origin.
3.In vitro clonal propagation of Achyranthes aspera L. and Achyranthes bidentata Blume using nodal explants
Gnanaraj Edward Wesely ; MarimuthuAntonisamy Johnson ; RB Mohanamathi ; Subramanian Marappampalyam Kavitha
Asian Pacific Journal of Tropical Biomedicine 2012;(1):1-5
Objective: To develop the reproducible in vitro propagation protocols for the medicinally important plants viz., Achyranthes aspera (A. aspera) L. and Achyranthes bidentata (A. bidentata) Blume using nodal segments as explants. Methods: Young shoots of A. aspera and A. bidentata were harvested and washed with running tap water and treated with 0.1% bavistin and rinsed twice with distilled water. Then the explants were surface sterilized with 0.1% (w/v) HgCl2 solutions for 1 min. After rinsing with sterile distilled water for 3-4 times, nodal segments were cut into smaller segments (1 cm) and used as the explants. The explants were placed horizontally as well as vertically on solid basal Murashige and Skoog (MS) medium supplemented with 3% sucrose, 0.6% (w/v) agar (Hi-Media, Mumbai) and different concentration and combination of 6-benzyl amino purine (BAP), kinetin (Kin), naphthalene acetic acid (NAA) and indole acetic acid (IAA) for direct regeneration.Results:Adventitious proliferation was obtained from A. aspera and A. bidentata nodal segments inoculated on MS basal medium with 3% sucrose and augmented with BAP and Kin with varied frequency. MS medium augmented with 3.0 mg/L of BAP showed the highest percentage (93.60±0.71) of shootlets formation for A. aspera and (94.70±0.53) percentages for A. bidentata. Maximum number of shoots/explants (10.60±0.36) for A. aspera and (9.50±0.56) for A. bidentata was observed in MS medium fortified with 5.0 mg/L of BAP. For A. aspera, maximum mean length (5.50±0.34) of shootlets was obtained in MS medium augmented with 3.0 mg/L of Kin and for A. bidentata (5.40±0.61) was observed in the very same concentration. The highest percentage, maximum number of rootlets/shootlet and mean length of rootlets were observed in 1/2 MS medium supplemented with 1.0 mg/L of IBA. Seventy percentages of plants were successfully established in polycups. Sixty eight percentages of plants were well established in the green house condition. Sixty five percentages of plants were established in the field. Conclusions: The results have shown that use of nodal buds is an alternative reproducible and dependable method for clonal propagation of A. aspera and A. bidentata. The high rate of direct shoot-root multiplication and their high rate of post-hardening survival indicate that this protocol can be easily adopted for commercial large scale cultivation.