Aims: Mangroves of Tanjung Lumpur, Kuantan, Pahang is considered as a relatively underexplored resource of actinomycetes. Based on the above perspective, a study was conducted on mangrove sediments of Tanjung Lumpur, Kuantan to isolate potential actinomycetes using several pretreatments and various selective media. Methodology and results: Sediments from five different sites at Tanjung Lumpur mangrove were collected and selectively pre-treated. The pretreated sediments were diluted and plated onto eight different selective media. A total of 172 potential actinomycetes were isolated from all the media. Antimicrobial activities of 61 selected strains were checked against 8 test microorganisms using cross streak method. Pretreatment of wet heat with seawater was the most effective method for the isolation of actinomycetes as it yielded a maximum of 105 actinomycete isolates and IM7 was the most suitable medium for actinomycete isolation with highest percentage of recovery (31 %). Forty three isolates (70.5 %) showed antimicrobial activities against one or more test microorganisms. Isolates IIUM B21 and IIUM B31 showed antimicrobial activity against all test microorganisms. Seven isolates showed antifungal activity as they inhibited only C. albicans. Ten isolates were randomly selected for identification based on partial sequences of 16S rRNA gene. Six isolates were found belong to the genus Streptomyces, two isolates belong to the genus Micromonospora and two isolates were identified as Rhodococcus spp. Conclusion, significance and impact of study: These findings revealed the potential of mangrove sediment of Tanjung Lumpur as an important source of actinomycetes with biosynthetic capabilities which might be beneficial to pharmaceutical industries.
Rhizophoraceae ; Actinobacteria

Aims: Research on lignin degradation capability is previously restricted exclusively to fungal enzymes. However, recent studies had successfully revealed several soil bacterial strains that were able to produce ligninolytic enzymes. These bacterial ligninolytic enzymes were claimed to be more specific in catalysing cleavage of certain linkages between phenolic units of lignin polymers as compared to fungal enzymes. The present study focuses on screening for ligninaseproducing bacteria isolated from South East Pahang Peat Swamp Forest (SEPPSF) soil using agar-based assay. Methodology and results: Thirteen isolates used in this study, which were selected based on distinctive colony morphology from our previous isolation work, showed decolourisation zone on Azure B plates screening. The ratio of decolourisation zones were measured to the ratio of the colony size and the biggest ratio was 2.22 by isolate AR1. Only 4 out of the 13 isolates were able to grow on lignin plates. Subsequently, the 4 isolates, AR3, AR8, AR10 and AR13 were tested on M1 agar supplemented with 3 ligninolytic enzyme indicator compounds which were tannic acid (TA), guaiacol and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) respectively. All four isolates showed growth on TA plates while only AR10 showed a clear brown coloration. An Intense reddish-brown colour formation was observed around the colony of isolates AR3 and AR10 on guaiacol plates while none exhibited green coloration around the colonies when tested on ABTS plates. Conclusions, significance and impacts of study: Isolate AR10 that was identified as Serratia sp. was perceived to be a potential ligninase-producer, though in-depth analysis has to be conducted in the future to determine the specific ligninolytic enzyme activities and characteristics. The application of different substrates is essential to investigate the ligninolytic potential and reaction of those bacterial enzymes towards different indicator compounds. This study is a preliminary endeavour concerning potential ligninolytic enzymes from bacteria as biocatalysts in various industrial processes. This is the first report on preliminary study for ligninolytic activities of soil bacteria from SEPPSF soil.

Aims: Previously described as non-favorable-microbial habitat, peat swamp forest has its own features, which are extremely acidic, poor in nutrient, water-logged and anoxic environment where rate of decomposition of plant litters is quiet slow. Interestingly, current research has proven that there is diversity of microbial communities in this ecosystem. The main objective of this study is to isolate bacteria from Pekan peat swamp forest soil that play a role in the decomposition of plant litters through cultivation on different agar-based medium. The success of isolation of bacteria from this neglected habitat could open the opportunity in unleashing the specific role of bacteria in peat swamp plant litter degradation as well as potential biotechnological application of these bacteria in lignocellulose-related industry. Methodology and results: To mimic the peat condition that is low in nutrient and comprised of plant debris, M1 and peat agar supplemented with cellulose, glucose, lignin and xylan were used. Specifically, for the isolation of actinomycetes, dry and wet heat pre-treatments were applied to the soil samples. Then, the samples were cultivated on three different agars which were oatmeal agar as well as M1 and peat agar supplemented with glucose. Enrichment method was applied in the isolation of cellulase-producing bacteria. It was found that higher number of bacteria and actinomycetes were successfully isolated from peat agar, followed by oatmeal agar and M1. In fact, more actinomycetes were isolated from soil that was treated with wet heat pre-treatment compared to dry heat pre-treatment and on peat agar compared to M1 and oatmeal agar. This finding is promising, indicating that the application of peat water in the agar-based medium is useful to mimic the actual environment of peat swamp and increase the possibility to isolate indigenous bacteria. Primary screening of isolates from samples enriched with carboxymethyl cellulose (CMC) showed positive result of decolourisation zone on Azo-CM-Cellulose agar indicating the ability of isolates to degrade cellulose compound. Conclusions, significance and impacts of study: The study indicates the effectiveness of different culture media in successful isolation of bacteria including actinomycetes. Using the enrichment method, bacteria that are able to degrade cellulose compound was successfully isolated even though it is well known that plant litter degradation in the peat swamp environment happens at very slow rates.
Bacteria

Objective To prove probable relations between serum E3 SUMO-protein ligase NSE2 (NSMCE2) concentration, peroxynitrite related to oxidative stress in nephrolithiasis patients. Methods A total of 60 patients with nephrolithiasis and 50 healthy volunteers were involved in this study. Colorimetric method was used to detect blood urea, creatinine, uric acid, protein, albumin, total antioxidant status, total oxidant status, peroxynitrite, nitric oxide and oxidative stress index. Glutathione, NSMCE2 and superoxide dismutase were measured by ELISA. Results A significant increase in level of peroxynitrite, total oxidant status, NSMCE2 and oxidative stress index in patients was observed, while total antioxidant status and glutathione were significantly decreased. Conclusions The study concluded that serum NSMCE2 significantly correlated with peroxynitrite and oxidative stress in patients with nephrolithiasis.