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Melanin is a pigmented material varies from yellow to black color dependent on the type of melanin. Not all the microorganisms can produce this material, most industrial researchers are looked after about melanin that produced from environmental microorganisms and little is known about from pathogenic bacteria and its role in pathogenesis. Therefore this study is aimed to focus on the role of melanin produces by one pathogenic bacteria(Klebsiella pneumoniae) isolated from an infected wound on host immune responses.The results of this study showed, that the increasing melanin concentration leads to decrease in the phagocytic index. and in vivo tests are done by using different concentration of extracted microbial melanin, These concentrations showed variable effects on tested cytokines( IL-1β , IL-12 , TNF-α , IL-10 , IFN-γ and IL-4) In conclusion, microbial melanin is act as virulence factor throughout suppress the most important pro-inflammatory cytokines and that squeal to counteract immune responses. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Lignolytic (lignin degrading) enzyme, from oil palm pathogen Ganoderma boninense Pat. (Syn G. orbiforme (Ryvarden)), is involved in the detoxification and the degradation of lignin in the oil palm and is the rate‐limiting step in the infection process of this fungus. Active inhibition of lignin‐degrading enzymes secreted by G. boninense by various naturally occurring phenolic compounds and estimation of efficiency on pathogen suppression was aimed at. Methods and Results: In our work, 10 naturally occurring phenolic compounds were evaluated for their inhibitory potential towards the lignolytic enzymes of G. boninense. Additionally, the lignin‐degrading enzymes were characterized. Most of the peholic compounds exhibited an uncompetitive inhibition towards the lignin‐degrading enzymes. Benzoic acid was the superior inhibitor to the production of lignin‐degrading enzymes, when compared between the 10 phenolic compounds. The inhibitory potential of the phenolic compounds towards the lignin‐degrading enzymes are higher than that of the conventional metal ion inhibitor. The lignin‐degrading enzymes were stable in a wide range of pH but were sensitive to higher temperature. Conclusion: The study demonstrated the inhibitor potential of 10 naturally occurring phenolic compounds towards the lignin‐degrading enzymes of G. boninense with different efficacies. Significance and Impact of the Study: The study has shed a light towards a new management strategy to control basal stem rot disease in oil palm. It serves as a replacement for the existing chemical control. [ABSTRACT FROM AUTHOR]

In this study, the isolation of sulphur oxidising bacteria (SOB) from hot spring in Malaysia was carried out in an enrichment culture using sodium thiosulphate as a sole energy and CO2 as a sole carbon source. A total number of 80 SOB isolates were obtained from the agar plate and considered as positive SOB due to their abilities using thiosulphate for growth. All the isolates were initially screened for their fast growths in liquid medium and 13 isolates were selected for another screening process. Three SOB isolates namely isolate AH18, AH25, and AH28 were selected based on their abilities to grow faster, produce the highest sulphate ion and reducing the pH in the growth medium. The cells were Gram-negative and short rod-shaped. The effects of various variables including temperature (25-45 °C), pH (4-9), sodium thiosulphate concentrations (4-100 mM) and metabolic characteristic were evaluated on bacterial growth and their sulphur oxidation activities. The optimum pH of all the potential isolates occurred at pH 8.0. Meanwhile, the optimum temperature for isolate AH18, AH25 and AH28 occurred at 45 °C, 30 °C, and 30- 45 °C, respectively. The three isolates were classified as facultative chemolithotroph with the capability of growth in thiosulphate concentration as high as 100 mM. Therefore, given the ability in the oxidation of thiosulphate, temperature and pH adaptabilities, with the metabolic flexibilities of isolates AH18, AH25, and AH28 could be a good H2S biological deodorizing candidate. [ABSTRACT FROM AUTHOR]

The study was undertaken to characterize plant growth promoting rhizobacteria (PGPR) for growth enhancement and stress tolerant traits and their efficacy on early establishment of rice seedling. In vitro growth promoting traits revealed that out of 30 PGPR isolates, 18 fixed nitrogen, 17 solubilized tri-calcium phosphate, 29 and 17 produced IAA with or without addition of L-tryptophane. In case of stress tolerant activities, PGPR isolates tolerated pH ranging from 5 to 10, Nacl from 1 to 6% and polyethylene glycol (PEG) from 10 to 40%, respectively. They showed antagonistic activity against Pyricularia oryzae with PIRG values ranging from 7-68%. After two-stage of screening, isolates UPMR7 and UPMR17 were identified based on 16s rRNA gene sequences and matched to the genus Bacillus and Citrobacter with 97-98% similarity. UPMR 7 and UPMR 17 were further evaluated on early growth promotion of rice variety MR219. Results revealed that PGPR inoculation had significant effects on plant growth compared to non-inoculated plants. Thus, it could be suggested that the isolates UPMR7 and UPMR17 have the potential to be used as biofertilizer and bioenhancer in sustainable rice cultivation. [ABSTRACT FROM AUTHOR]

Oil palm tissues are rich in polyphenols, polysaccharides and secondary metabolites; these can co-precipitate with RNA, causing problems for downstream applications. We compared two different methods (one conventional and a kit-based method - Easy-Blue(TM) Total RNA Extraction Kit) to isolate total RNA from leaves, roots and shoot apical meristems of tissue culture derived truncated leaf syndrome somaclonal oil palm seedlings. The quality and quantity of total RNA were compared through spectrophotometry and formaldehyde gel electrophoresis. The specificity and applicability of the protocols were evaluated for downstream applications, including cDNA synthesis and RT-PCR analysis. We found that the conventional method gave higher yields of RNA but took longer, and it was contaminated with genomic DNA. This method required extra genomic DNA removal steps that further reduced the RNA yield. The kit-based method, on the other hand, produced good yields as well as well as good quality RNA, within a very short period of time from a small amount of starting material. Moreover, the RNA from the kit-based method was more suitable for synthesizing cDNA and RT-PCR amplification than the conventional method. Therefore, we conclude that the Easy-BlueTM Total RNA Extraction Kit method is suitable and superior for isolation of total RNA from oil palm leaf, root and shoot apical meristem.

Peat moss (PM) is the most widely used growing substrate for the pot culture. Due to diminishing availability and increasing price of PM, researchers are looking for viable alternatives for peat as a growth media component for potted plants. A pot study was conducted with a view to investigate the possibility of using spent mushroom waste (SMW) for Kai-lan (Brassica oleracea var. Alboglabra) production replacing peat moss (PM) in growth media. The treatments evaluated were 100% PM (control), 100% SMW, and mixtures of SMW and PM in different ratios like 1 : 1, 1 : 2, and 2 : 1 (v/v) with/without NPK amendment. The experiment was arranged in a completely randomized design with five replications per treatment. Chemical properties like pH and salinity level (EC) of SMW were within the acceptable range of crop production but, nutrient content, especially nitrogen content was not enough to provide sufficient nutrition to plant for normal growth. Only PM (100%) and SMW and PM mixture in 1 : 1 ratio with NPK amendment performed equally in terms of Kai-lan growth. This study confirms the feasibility of replacing PM by SMW up to a maximum of 50% in the growth media and suggests that NPK supplementation from inorganic sources is to ensure a higher productivity of Kai-lan.