Metabolic extract of the endophytic fungus Flavodon flavus isolated from Justicia brandegeana in the control of Alicyclobacillus acidoterrestris in commercial orange juice.

In this work, the antibacterial activity of a crude extract of the endophytic fungus Flavodon flavus (JB257), isolated from leaves of Justicia brandegeana, was evaluated against both the vegetative and sporulated forms of Alicyclobacillus acidoterrestris. The microdilution technique was performed in order to determine the antibacterial activity of the crude extract alone as well as in combination with the bacteriocin, nisin. The minimum inhibitory concentration (MIC) of the crude extract and nisin alone against A. acidoterrestris vegetative forms were 250 µg/mL and 31.5 µg/mL, respectively, while the minimum bactericidal concentrations (MBC) were 1000 µg/mL and 62.5 µg/mL,respectively. For A. acidoterrestris spores, treatment with the crude extract at a concentration of 500 µg/mL caused a 47% reduction in growth, while nisin at 62.5 µg/mL could reduce 100% of the growth. The in vitro evaluation of the crude extract combined with nisin against A. acidoterrestris by the Checkerboard method showed a synergistic interaction between the two compounds. In addition, greater selectivity towards bacterial cells over host cells, a human hepatocyte cell line, was achieved when the crude extract was combined with nisin, Using scanning electron microscopy, interferences in the cell membrane of A. acidoterrestris could be observed after treatment with the crude extract. The results presented in this study indicate that the crude extract of the endophyte F. flavus has biotechnological potential in the food industry, especially for the treatment of orange juices through the control of A. acidoterrestris.

Enhanced cytotoxic activity of endophytic bacterial extracts from Adhatoda beddomei leaves in A549 lung cancer cell lines.

AIM OF THE STUDY: The current study is aimed to isolate and study the efficacy of the anticancer activity of endophytic bacteria from adhatoda beddomei leaves. Endophytic bacteria, microorganisms can found in the plant tissues, like leaves, branches and roots and able to produce various novel secondary metabolites for the medicinal applications. METHODOLOGY: Endophytic bacteria were isolated from the leaves of the adhatoda beddomei leaves. The extract from the culture was tested for the cytotoxicity in A549 cell lines using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)assay, dual staining and nuclear staining. RESULTS: The expression of the apoptotic and proliferative genes were assessed with the reverse transcriptase polymerase chain reaction (RT-PCR) comparing with the control gene. The inhibitory concentration (IC50) of the bacterial extract was found to be 43.97 µg/ml. With the dual staining the apoptotic cell percentage was significantly increased (P < 0.001) and with the 40µg/ml and 80µg/ml concentration the apoptotic percentages observed as 67% and 89% respectively. Similar concentrations were used for the nuclear fragmentation (PI) and the cell cycle analysis (FACS) using WinMDI 2.9 software. During cell cycle analysis the accumulation of the cells at G0-G1 stage was observed with increasing concentrations of the chi-alg encophytic bacterial extract nanoparticles. Finally the proapoptotic and proliferative gene expression for the bax, Bcl-2 and caspase was significantly regulated (P < 0.01; P < 0.05). The Bax and Caspase were up-regulated and Bcl-2 was down regulated. CONCLUSION: The results conclude that enophytic bacterial extract possess good cytotoxic activity.

Arbuscular mycorrhiza-like biotechnological potential of Piriformospora indica, which promotes the growth of Adhatoda vasica Nees

We report the growth promoting potential of Piriformospora indica, which is a newly discovered arbuscular mycorrhiza-like fungus. It is a facultative symbiont and unlike arbuscular mycorrhizal fungi, it can be cultured in vitro. Adhatoda vasica is a medicinal plant. Rapid proliferation of roots was recorded in A. vasica withan important root colonization estimated to 95 percent after 6 months. P. indica improved growth of A. vasica. This association forms a new host-symbiont combination.