Influence of Culture Media, Temperature and pH on Colletrotrichum gleosporioides, Isolated from Carica papaya in Besut, Terengganu, Malaysia

Colletotrichum gleosporioides is known as the causal agent of anthracnose disease in Malaysia. Economic losses are reported during postharvest where the disease incidence and severity was recorded as 90-98 % and 25-38 % respectively. Colletotrichum spp. were isolated from lesions of infected Carica papaya L. that showing the typical anthracnose disease symptoms in Besut, Terengganu, Malaysia. Three types of fungal cultures were obtained that are identified as Colletotrichum sp., Fusarium sp. and Rhizoctonia sp. One of the fungal obtained was confirmed as Colletotrichum gleosporioides based on conidial morphology and growth characteristics on PDA media. The pathogen under study varied in its ability to grow under different environmental conditions. However, isolate preferred temperature range of 20°C to 30°C for the growth on PDA media. C. gloeosporioides isolates grew well at pH values within range of pH6 to pH 7

Identification and prevention of microbial contaminants in Musa paradisiaca tissue culture

Banana (Musa spp.) is an economically vital fruit crop in Malaysia and therefore, micropropagation was applied to meet the market demand for disease-free seedlings. However, microbial contamination is a significant obstacle in micropropagation techniques. In this research, the microorganisms that were present in the banana culture were characterized and the efficacy of antimicrobial and antifungal agents to inhibit contaminants was evaluated. Three bacterial and two fungal isolates were isolated from the contaminated culture. Klebsiella pneumoniae, Klebsiella quasipneumoniae, and Klebsiella variicola were identified by molecular identification based on the 16S rDNA sequence. The gram-staining method confirmed all three bacteria were gram-negative. Oxidase and catalase tests showed the presence of cytochrome oxidase system and catalase enzyme in all bacteria. The bacteria can also hydrolyze starch, ferment sugars, and reduce sulfur from the amylase test. Phenotypic identification of fungi revealed the presence of conidia and hyphae, indicating the presence of Colletotrichum spp. and Aspergillus spp. In fungi characterization, Colletotrichum gloeosporioides and Aspergillus flavus were detected. Chloramphenicol was identified as an effective antibacterial agent from the disc diffusion method. Fluconazole was a potent antifungal agent by screening the sterilizing agents. The findings may potentially lead the way for the implementation of reducing the contamination rate in banana micropropagation

Molecular Identification of Isolated Fungi from Kelantan and Terengganu Using Internal Transcriber Spacer (ITS) Region

Fungi are morphologically, ecologically, metabolically and phylogenetically diverse. Fungi play important roles as one of the major decomposer in ecosystems, dominated by Saprophytic fungi. The identification of fungi is important to differentiate each fungi owing to their special ability in our ecosystem. However, the identification of fungi is become very challenging for those untrained mycologists.  Essentially, the identification of fungi at the species-level is more problematic. Traditional approaches, based on the morphological or physiological features alone are unreliable because of the limited amount of morphological characters for fungi identification. Thus, a reliable molecular approach is required to identify the fungi at species-level. Here, we have successfully identified the species of 25 isolated fungi samples from the polluted areas in Kelantan and Terengganu by using the molecular identification utilizing the ITS1-5.8S-ITS2 regions. Phylogenetics tree was then constructed, using MEGA v7.0 software to illustrate the inter-relationships among the isolates. Among of 25 isolated fungi samples, 23 were identified from Ascomycota division and another two were from the Zygomycota division. From our observation, the most frequent species grew for both polluted areas were from Lasiodiplodia sp

Proses identifikasi jenis bakteria dengan menggunakan aplikasi BactFinder© (bacterial identification process using BactFinder© mobile application) / Nadiawati Alias … [et al.]

BactFinder© merupakan aplikasi interaktif dan mudah alih yang dibina untuk memudahkan identifikasi dan pengenalpastian jenis bakteria yang ingin dikaji. Seperti yang diketahui umum, bakteria terdiri daripada domain mikroorganisma prokariotik yang besar dan pelbagai jenis, justeru itu pengenalpastian kumpulan bakteria ini memerlukan satu proses identifikasi yang sistematik dan teratur. Melalui aplikasi mudah alih ini, maklumat hasil daripada uji kaji biokimia dan ujian morfologi yang diperoleh daripada uji kaji di makmal perlu dimasukkan ke dalam aplikasi ini sebelum pengenalpastian bakteria boleh dilakukan. Sebelum ini, kaedah untuk pengenalpastian jenis bakteria memerlukan ahli akademik serta para pelajar untuk merujuk kepada buku-buku rujukan, artikel-artikel serta jurnal saintifik yang berkaitan. Proses ini sudah tentu memakan masa yang agak panjang dan kurang efektif. Aplikasi mudah alih ini dilengkapkan dengan pangkalan data bagi 19 jenis ujian biokimia termasuk bakteria morfologi. Pangkalan data ini dibina merujuk kepada Bergey’s Manual of Systematic Bacteriology, Bergey’s Manual of Determinative Bacteriology dan juga jurnal-jurnal saintifik yang berkaitan. Aplikasi mudah alih BactFinder© ini terbukti dapat memberikan respon yang cepat (±2 saat) dan tepat dalam membantu para pelajar dan ahli akademik dalam proses pengenalpastian bakteria yang sedang dikaji di makmal. Aplikasi ini juga amat sesuai digunakan oleh pelajar prasiswazah, pascasiswazah dan ahli akademik dalam bidang mikrobiologi, bioteknologi dan sains secara umumnya

Identification and Characterization of The Causal Agent of Infected Iceberg Lettuce (Lactuca Sativa L.) in Perak, Malaysia

Lack of knowledge about the causal agent of infected crops lead farmers to use wrong treatment on their crops, which is causing negative effects on environment and human’s health. This study was conducted to identify and characterize the causal agent from the infected iceberg lettuce (Lactuca sativa L.) in Perak, Malaysia. The infected iceberg lettuces were sampling from Perak area and the causal agent was isolated by direct plating technique on a nutrient medium. The isolated bacteria were identified by molecular method and biochemical test. Molecular identification was carried out using 16S rRNA sequence and then, several tests such as amylase, catalase, oxidase and others were done for identification of bacterial species based on their biochemical activities. The obtained results showed that Serratia marcescenes and Stenotrophomonas sp. were identified as the causal agents. The pathogenicity has been confirmed by the establishment of Koch’s Postulate, which showed 100% disease infection on them. The environmental effects also have been tested on the bacteria to study the ability of bacteria to grow in different environmental conditions based on different in pH, salinity, and temperature. All the bacterial sample showed that they able to growth on the pH between 4.0 to 9.0, at the temperature 10 °C to 45 °C and at the addition salinity to the medium between 2.5 %, 5.0% and 7.5 %. Keywords: Stenotrophomonas sp., Serratia sp., lettuce, lettuce diseas

Seasonal Variation of Water Quality at Sungai Chanteq and Sungai Dendong

Water is important for all the living things as water is one of the components build up in plant, animal and human. Rivers are an important source for domestic, industrial as well as agriculture sector. The aim of this study was to assess the physicochemical and biological parameter from two rivers located at Pasir Akar Farm and Tembila. Water Quality Index (WQI) related to the quality status of the water. From the two sampling stations in different rivers were sampled from December 2017 until March 2018. Eight water quality parameters were analyzed based on in-situ and ex-situ analysis at two different time. According to HACH and American Public Health Association (APHA) methods. A total eight parameters were measured and analyzed for both rivers. Based on Malaysia Water Quality Index (WQI) shows the water quality value for Sungai Dendong 71.56 which is class III and for Sungai Chanteq value is 89.99 which in class II. Based on Water class and guideline of Malaysia, class II water quality need conventional requirement to treat the water while class III need extensive treatment required in order to serve for use in the agricultural sector surround the are

Potential of Pseudomonas sp. & Bacillus sp. for Controlling Fusarium oxysporum, A Causal Agent For Rockmelon Fusarium Wilt Disease

Fusarium sp. recognized as among main pathogen to the rockmelon. The disease was renown as Fusarium wilt disease (FWD). As to the FWD, objectives of this study were to obtain the pure culture of Fusarium oxyporum f. sp. melonis (Fom), and to control the Fom via biological control method using effective bacteria. Beside, the study was also screened the plant growth promoting properties of Pseudomonas sp. and Bacillus sp.. Fusarium oxysporum f. sp. melonis Snyder & Hans caused postharvest disease problem affecting melon production and loss almost 100 % due to this destructive disease. Effective bacteria like Bacillus sp. and Pseudomonas sp. has a good potential to suppress growth of pathogen. Based on the phenotypic identification and morphological characterization of fungus isolated was identified as Fusarium oxysporum f. sp. melonis and it was than confirmed with molecular methods with 99% similarity. Environmental factors that give the optimum growth of Fusarium were evaluated. Based on the result, the growth of fungus showed the best on PDA media (2.538 ± 0.095 cm), 30 °C (2.475 ± 0.096 cm), pH 4 (2.700 ± 0.216 cm) and under continuous dark condition (3.433 ± 0.115 cm). The Bacillus sp. (DP - 1) showed the highest antagonistic activity of fungus and bacteria with 70.68 % in dual culture assay and highest inhibition of fungus growth in double layer test with no ability to growth. As production of protease, all 7 bacteria tested showed positive result of by producing clear zone on PDA media except by B43. From several parameter tested, the result showed that Bacillus sp. has more potential as biological control agent to control the Fusarium wilt disease in rockmelon plant compared to Pseudomonas sp.

Potential of Pseudomonas sp. (UniSZA-MKB10) and Bacillus spp. (UniSZA-BK3, UniSZA-BK4 and UniSZA-DA) as Biological Control Agent for Controlling Anthracnose Disease of Carica papaya L.

Colletotrichum gleosporioides is known as the causal agent of anthracnose disease of Carica papaya in Malaysia. Economic losses are mostly reported during postharvest where the disease incidence and severity was recorded as 90-98 % and 25-38 % respectively. Colletotrichum sp. were isolated from lesions of infected C. papay that showing the typical anthracnose disease symptoms. Three types of fungal cultures were obtained and identified as Colletotrichum sp., Fusarium sp. and Rhizoctonia sp. One of the fungal obtained that was confirmed to be C. gleosporioides is based on morphological characteristics on PDA and  Koch’s Postulate has confirmed C. gleosporioides as causal agent of papaya antracnose disease. The pathogen under study varied in its ability to grow under different environmental conditions. However, isolate preferred temperature range of 20°C to 30°C for the growth on PDA media. C. gloeosporioides isolates grew well at pH values within range of pH 6 to pH 7. Four bacterial strains, UniSZA-MKB10, UniZA-BK4, UniSZA-BK3 and UniSZA-DA, were tested in this study and proved to have antifungal properties against C. gloeosporioides. Dual culture assay, double layer and double plate method were conducted to test their metabolites as well as diffusible and volatiles antibiotic compound of bacteria. Out of four, three bacterial were found to show inhibition ability with MKB10 showed highest percentage of inhibition on radial growth with 62.08 ± 3.64% PIRG as well as produced greater diffusible and volatiles substances that significantly (P<0.05) inhibited the mycelial growth of C. gloeosporioides with PIRG of 85.48 ± 1.53 % and 31.03 ± 2.56 % respectively, and followed by UniSZA-DA. Culture filtrate of BK4 also showed highest significance effect towards inhibition of spore germination where the germ tube produced is the shortest (0.9055 µm) 

Bio-Ethanol Production from Fruit and Vegetable Waste by Using <em>Saccharomyces cerevisiae</em>

Waste from the food is a challenge to the environment all over the globe, hence there is need to be recycled. Vegetables and fruits biomass is a resource of renewable energy with significant fuel source potential for the production of electricity and steam, fuel for consumption and laboratory solvents. Bioethanol derived from biomass contributed 10–14% of the total world energy supply and solved the world crisis such as global warming and depletion of fossil fuel. Presently, bioethanol is a global issue on the efforts to reduced global pollution, contributed significantly by the petroleum or diesel combustion or combination of both. Vegetables and fruits waste significantly contains high sugar which can be utilized and serve as a raw material in the production of renewable energy using Saccharomyces cerevisiae. Though 80% of the current bioethanol are generated from edible materials such as starch and sugar. Biomass from lignocellulosic gathered more attention recently. The objective of this review is to account for the procedures involved in the production of bioethanol from biomass of fruits and vegetable waste through a fermentation process using Saccharomyces cerevisiae. In this chapter, we discussed the biomass preparation and fermentation techniques for bioethanol and reviewed the results of different fruits and vegetable waste. We found pineapple and orange fruit biomass contain a higher amount of bioethanol and easier to extract than the other fruit and vegetable wastes. Recent review coined out that dry biomass of fruit and vegetable is a promising feedstock in the utilization of bioethanol production

Trichoderma atroviride isolated from mangroves of the east coast of Peninsular Malaysia exhibited high tolerance against heavy metal cadmium

The toxicity of the heavy metal cadmium to organisms is known, with differing tolerance in different organisms. The ability of fungi to survive in sites polluted with heavy metals has led to its mechanism of heavy metal tolerance being widely investigated. However, little work has addressed cadmium tolerance in fungi isolated from mangroves, the heavy metal basin. Therefore, this study was carried out to isolate fungi and investigate their tolerance towards cadmium. Samples used were obtained from the mangroves in the east coast of Peninsular Malaysia. Aquatic fungal isolates were selected for cadmium-tolerance screening, in the range of 0 to 0.5 mM. The identification of the most tolerant fungus was confirmed using the molecular approach and used further to study its tolerance in higher concentrations of cadmium. A total of 25 fungi was isolated and seven isolates were classified as aquatic fungi. Trichoderma sp. was shown to be the most tolerant towards cadmium. The sequencing result of the amplified fungal gene confirmed its identity as Trichoderma atroviride. Further tolerance test showed that the fungus survived in 3.0 mM, the highest concentration tested, although at a slower growth rate and with affected sporulation. These results can be the baseline data for further investigations on the mechanism of cadmium detoxification in T. atroviride, thus enhancing its potential as a heavy metal bioremediator