1.Bioactive compounds and antioxidant activity of rice bran fermented with lactic acid bacteria
Nur Yuhasliza Abd Rashid ; Dang Lelamurni Abd Razak, Anisah Jamaluddin ; Shaiful Adzni Sharifuddin ; Kamariah Long
Malaysian Journal of Microbiology 2015;11(2):156-162
Aims: Rice bran has been documented as a rich source of bioactive compounds such as gamma-oryzanol, phenolic
acids, phytic acid, β-sitosterol and vitamin E, which offer beneficial health properties and confer antioxidant activity
related benefits. The objective of this research is to evaluate the bioactive compounds content of fermented rice bran
such as organic acids, ɣ-oryzanol, α- tocopherol and phenolic acids using three lactic acid bacteria (LAB), namely
Pediococcus acidilactici, Lactococcus lactis and Pediococcus pentoseous in a solid state fermentation.
Methodology and results: High performance liquid chromatography (HPLC) was used to analyze the concentration of
the active compounds in rice bran. The most abundant organic acids detected in fermented rice bran samples were
lactic acid and acetic acid, which showed significant improvement after fermentation. Fermentation of rice bran with P.
acidilactici showed a two-fold increment in ɣ-oryzanol and α-tocopherol compared to unfermented rice bran. A higher
concentration of ferulic acid was observed in rice bran fermented with P. acidilactici compared to other strains.
Meanwhile, coumaric acid concentration in all fermented samples decreased significantly upon fermentation.
Conclusion, significance and impact of study: These results indicated that the fermentation with LAB could enhance
certain bioactive compounds production and antioxidant activity of rice bran. Therefore, improved rice bran has the
potential to be used as an ingredient in functional food and cosmetic formulation.
Keywords: Rice bran; bioactive compounds; fermentation, lactic acid bacteria; antioxidant activity
Fermentation
;
Oryza
2.Susceptibility of Malaysian rice varieties to Fusarium fujikuroi and in vitro activity of Trichoderma harzianum as biocontrol agent
Wan Nur Ain W. A. H ; Azmi A. R ; Jambari A ; Nur Ain Izzati M. Z
Malaysian Journal of Microbiology 2015;11(1):20-26
Aims: Bakanae disease on rice has been widely distributed in all countries where rice is grown commercially, especially
in Asian countries including Malaysia. As an alternative measure in controlling Fusarium fujikuroi, two approaches have
to be adapted i.e. by using resistant varieties and biocontrol agents as reported in the present study.
Methodology and results: A total of 31 Malaysian rice varieties were used in screening and results showed that variety
MR211 was the most susceptible and MR220 was slightly susceptible. Out of 60 isolates of Trichoderma harzianum
isolated from soils in Malaysia and tested against the pathogen under in vitro condition, 13 isolates showed high
percentage of inhibition (PIRG > 60%). All isolates of T. harzianum showed that the PIRGs were significantly different at
p≤0.05 with those of control plates.
Conclusion, significance and impact of study: Biocontrol agent and resistant variety are better alternative for
controlling plant diseases. We found a variety MR220 was slightly susceptible, but none of tested varieties is resistant
towards pathogen of bakanae disease. T. harzianum has the ability to inhibit the growth of F. fujikuroi (T3068P) under in
vitro condition. The findings of the Malaysian susceptible/resistant variety and potential T. harzianum isolate as a
biocontrol agent of bakanae are important for future tests in the plant house and field trials.
Biological Control Agents
;
Oryza
3.Assessment of multifunctional biofertilizer on rice seedlings (MR 219) growth in a greenhouse trial
Phua Choo Kwai Hoe ; Khairuddin Abdul Rahim ; Latiffah Norddin
Malaysian Journal of Microbiology 2015;11(2):195-198
Aims: Food security and safety are current issues around the world. Rice is a staple food for a large portion of the
world’s population, and in Malaysia around 2.2 million tonnes of rice were consumed annually. Fertilizer input is the key
to increase rice production. Malaysian Nuclear Agency (Nuclear Malaysia) has developed multifunctional biofertilizer
products in an effort to reduce dependency on chemical fertilizers for crop production.
Methodology and results: Multifunctional biofertilizer products contain indigenous microorganisms that have desired
characteristics, which include plant growth promoting, phosphate solubilising, potassium solubilising and enhancing N2-
fixing activity were used in this study. These products were formulated as liquid inoculants, which is suitable for rice
production. A greenhouse trial was conducted to evaluate the effectiveness of multifunctional biofertilizer on rice.
Multifunctional biofertilizer products were applied singly and in combination with rock phosphate, feldspar and irradiated
oligochitosan from a project by Forum for Nuclear Cooperation in Asia (FNCA), Japan. Plants that were given chemical
fertilizers and plants not receiving fertilizer or biofertilizer products were used as controls. Fresh and dry weights of rice
seedlings were determined. Application of multifunctional biofertilizer combined with irradiated oligochitosan (T3)
resulted in significantly higher fresh weights (97.12 g) and dry weights (84.16 g) as compared to non-treated plants
(77.39 g fresh weights and 69.56 g dry weights). The results suggested that application of multifunctional biofertilizer in
combination with irradiated oligochitosan could increase rice growth.
Conclusion, significance and impact of study: Combination of biofertilizer with oligochitosan increased rice growth in
greenhouse trial. Further investigation of this interaction phenomenon should be carried out.
Crop Production
;
Oryza
4.Effects of rice varieties on weight, blood glucose and triglyceride levels in sprague dawley rats.
Jenalynne Mareah O. CHUA ; Deo Al Patrick T. ALONSO ; Elise Angela H. ESPINOSA ; Aya Isabel B. GELONGA ; Abegail Visia Marie C. SILANG ; Ronald G. GARAVILLES
Acta Medica Philippina 2018;52(3):216-221
BACKGROUND: Rice is the staple food in the Philippines and the major carbohydrate source that greatly affects the weight, blood glucose and triglyceride levels of the population.
OBJECTIVE: The objective of the researchers was to determine the effects of white, brown and red rice varieties on weight, blood glucose and triglyceride levels in rats.
METHODS: Sprague Dawley rats were fed with diets of cooked rice of different rice variety; white, brown and red. Weight was measured using a digital laboratory weighing scale. Blood glucose and triglyceride levels were measured by glucometer (OneTouch®) and Humalyzer Primus®, respectively.
RESULTS: Rats fed with white rice had the greatest increase in weight and blood glucose levels, and red rice had the least increase. For the postprandial blood glucose test, all three rice groups reached their peak blood glucose level at 30 minutes, with white rice having the greatest value, followed by brown rice, and lastly, red rice. Rats fed with red rice had the greatest decrease in triglyceride level.
CONCLUSION: In this study, consumption of white rice contributes to weight gain, blood glucose level increase and minimal triglyceride level change compared to brown and red rice.
Animal ; Oryza ; Blood Glucose
5.Antibacterial activity of Sireh (Piper betle L.) leaf extracts for controlling bacterial leaf blight diseases in rice plant
Nor Umaira Abu Asan ; Yaya Rukayadi ; Geok Hun Tan
Malaysian Journal of Microbiology 2022;18(3):291-300
Aims:
This study aimed to determine the antibacterial activity of Piper betle L. leaf extract against Xanthomonas oryzae pv. oryzae that causes bacterial leaf blight in rice plant.
Methodology and results:
The antibacterial activity of the P. betle leaf extract (100, 50, 25 and 12.25 mg/mL) with four different solvents (methanol, ethyl acetate, hexane and acetone) was evaluated using a disc diffusion assay, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. The inhibition zone of methanolic extract appeared to have the maximum diameter compared to those of other extracts, which is 32.67 mm at a concentration of 100 mg/mL, followed by 30.33 mm, 22.00 mm and 20.30 mm for the concentrations of 50 mg/mL, 25 mg/mL and 12.5 mg/mL, respectively. The MIC and MBC values of the methanolic extract were 0.625 mg/mL suggesting that the extract has a bactericidal effect on X. oryzae pv. oryzae (Xoo). The time-kill curve studies revealed that the 1× MIC (0.625 mg/mL) concentration of methanolic extract had a time and concentration-dependent killing effect on Xoo. Gas chromatography-mass spectrometry (GC-MS) analysis of methanol extract revealed the presence of eugenol acetate (29.53%), 4-allyl-1,2-diacetoxybenzene (29.51%) and 2,3-dimethyl benzoic acid (22.82%) as major compounds.
Conclusion, significance and impact of study
The methanolic leaf extract of P. betle was proven to have an effective inhibitory effect on Xoo and may have the potential to be used as an alternative management strategy for controlling rice diseases. In the future study, the methanolic leaf extract of P. betle is one of the recommendations to be applied in glasshouse and field trials.
Piper betle
;
Oryza--microbiology
6.Advances in microbial enzymatic elimination of ethyl carbamate in Chinese rice wine.
Qingtao LIU ; Zhen KANG ; Guocheng DU
Chinese Journal of Biotechnology 2019;35(4):567-576
Ethyl carbamate (EC), a carcinogenic and teratogenic chemical that is widely distributed in various alcoholic beverages, has attracted much attention. Microbial enzymatic degradation of EC in rice wine is always efficient and attractive. In this review, we summarize the research progress and problems of microbial enzymatic elimination of EC in rice wine from three aspects: the mechanisms of EC formation in rice wine, the research progress of acid urease, and the research progress of urethanase. Then, we propose the corresponding strategies to solve the problems: screening new urethanase with satisfied enzyme properties, food-grade expression and directed evolution of the bifunctional Fe³⁺-dependent acid urease and acid urease used in combination with urethanase to eliminate both urea and EC in rice wine.
Oryza
;
Urea
;
Urease
;
Urethane
;
Wine
7.Study on content of ethyl carbamate in yellow rice wine and its change in Zhejiang province.
Xiang-hong SHEN ; Ping-gu WU ; Li-yuan WANG ; Jing ZHANG ; Ying TAN ; Ying YING ; Bing-jie MA
Chinese Journal of Preventive Medicine 2013;47(11):1036-1039
OBJECTIVETo understand the content status of ethyl carbamate (EC) in yellow rice wine and the changes in storage period and shelf life in Zhejiang province.
METHODSA total of 475 samples of yellow rice wine purchased randomly from supermarkets and food stores in Zhejiang province during 2008-2012, and 49 samples collected from manufacturers were measured for EC content. The sample collected from manufacturers by filter sterilization was placed at 4 °C, room temperature and 37 °C for 400 d, respectively;a bottled wine and a wine in bag were bought from market were placed for 400 d in room temperature to conduct shelf life storage test, and measure the content in every point in 2011. The EC of the samples was determinated by gas chromatography-mass spectrometry after the samples were diluted with D5-EC isotope dilution technique, and purified by alkaline diatomite solid phase extraction column.
RESULTSThe overall detection rate of EC was 99% (472/475) in yellow rice wine of Zhejiang province in 2008-2012, the median value was 70-112 µg/kg, the 90th percentile was 190-333 µg/kg, the 95th percentile was 214-393 µg/kg, and the maximum value was 430-515 µg/kg. The content of EC was increased gradually along with the increasing of storage age in commercially yellow rice wine, and the average content of EC were positively correlated with storage age(r = 0.988). The contents of EC in yellow rice wine after sterilization increased from 74 µg/kg to 86 µg/kg, 127 µg/kg and 509 µg/kg at 4 °C, room temperature and 37°C, respectively for 400 d storage, the differences had statistical significance (F = 14.73, P < 0.01). The content of EC in yellow rice wines in shelf life, which stored in room temperature with bottle and bag package, was decreased slightly with increasing storage time in the beginning, from 215 to 184 µg/kg and 196 to 158 µg/kg, respectively, and increased again with increasing storage time after 250 d, with 252 µg/kg and 210 µg/kg in bottle and bag package after 400 d, respectively, the differences had statistical significance (Z = 2.37, P < 0.05).
CONCLUSIONEC is widespread in rice wine, the content of EC was correlated with storage time and temperature.
China ; Oryza ; Urethane ; analysis ; Wine ; analysis
8.First Report of Rhizopus oryzae as a Postharvest Pathogen of Apple in Korea.
Jin Hyeuk KWON ; Jinwoo KIM ; Won Il KIM
Mycobiology 2011;39(2):140-142
Soft rot in apple caused by Rhizopus oryzae was found for the first time in Korea. A detailed description of the specimen is given along with its internal transcribed spacer rDNA sequence. The fungus was identified as Rhizopus oryzae based on the mycological characteristics, molecular data, and pathogenicity testing.
DNA, Ribosomal
;
Fungi
;
Korea
;
Oryza
;
Rhizopus
9.In vitro screening of siderophore-producing rice root endophytic bacteria from up-land paddies in north-western Vietnam for plant growth-promoting activities
Van Phuong Nguyen ; Thi Phuong Nga Mai ; Duc Chung Mai ; Hoang Ha Chu ; Tran Binh Le
Malaysian Journal of Microbiology 2022;18(1):17-26
Aims:
Endophytic bacteria (EB) living inside plant tissues possess different beneficial traits including siderophore production and other plant growth-promoting (PGP) activities. Siderophore-producing EB promote host plant growth by secreting ferrum in iron-deficient conditions. This study screened 19 siderophore producers in vitro, isolated from upland rice roots grown in mountain farms of Tung Village, Nậm Có Commune, Mù Cang Chải District, Yên Bái Province, Vietnam, for PGP traits, including phosphate solubilisation, indole-3-acetic acid (IAA), ammonia, gelatinase, amylase and catalase production.
Methodology and results:
The bacteria were identified by Matrix assisted Laser Desorption Ionization Time of Flight mass spectrometry (MALDI-TOF MS). All 19 isolates were identified as genera Pseudomonas, Enterobacter, Pantoe, Bacillus, Burkholderia, Staphylococcus, Ralstonia and Cronotacter. The isolates produced catalase and ammonia. The amount of ammonia ranged from 60.74 ± 0.14 to 466.72 ± 0.18 mg/L. Out of the 19 siderophore producers, 17 (89.47%) were able to solubilise phosphate with solubilisation index (PSI) ranging from 1.12 ± 0.07 to 2.14 ± 0.15. The qualitative assays identified 12 isolates (63.15%) positive for IAA production with a tryptophan concentration of 5 mM, whereas 15 (78.94%) and 17 (89.47%) isolates were positive for gelatin and starch hydrolysis, respectively. Especially, 7 isolates were found to be positive for all tested assays in vitro including Pseudomonas rhodesiae (NC2), Enterobacter asburiae (NC50), Pantoea ananatis (NC63), Bacillus cereus (NC64), Burkholderia cenocepacia (NC110), Staphylococcus sciuri (NC112) and Ralstonia pickettii (NC122).
Conclusion, significance and impact of study
This study serves as crucial findings of multi-trait plant growth-promoting endophytic bacteria isolated from upland rice root in north-western Vietnam. The seven potential isolates positive for all tested assays could be effective PGP bacteria for bio-inoculants.
Oryza--microbiology
;
Siderophores
;
Plant Growth Regulators
;
Vietnam
10.Soluble extract of soybean fermented with Aspergillus oryzae GB107 inhibits fat accumulation in cultured 3T3-L1 adipocytes.
Kyoung Ha SO ; Yasuki SUZUKI ; Shinichi YONEKURA ; Yutaka SUZUKI ; Chan Ho LEE ; Sung Woo KIM ; Kazuo KATOH ; Sang Gun ROH
Nutrition Research and Practice 2015;9(4):439-444
BACKGROUND/OBJECTIVES: This study was conducted to investigate the effects of fermented soybean (FS) extract on adipocyte differentiation and fat accumulation using cultured 3T3-L1 adipocytes. MATERIALS/METHODS: 3T3-L1 adipocytes were treated with FS and nonfermented soybean (NFS) extract during differentiation for 10 days in vitro. Oil red O staining was performed and glycerol-3-phosphate dehydrogenase (GPDH) activity was measured for analysis of fat accumulation. Expressions of adipogenic genes were measured. RESULTS: Soluble extract of soybean fermented with Aspergillus oryzae GB107 contained higher levels of low-molecular-weight protein than conventional soybean protein did. FS extract (50 microg/ml) inhibited adipocyte differentiation and fat accumulation during differentiation of 3T3-L1 preadipocytes for 10 days in vitro. Significantly lower GPDH activity was observed in differentiated adipocytes treated with the FS extract than those treated with NFS extract. Treatment with FS extract resulted in decreased expression levels of leptin, adiponectin, and adipogenin genes, which are associated with adipogenesis. CONCLUSIONS: This report is the first to demonstrate that the water-soluble extract from FS inhibits fat accumulation and lipid storage in 3T3-L1 adipocytes. Thus, the soybean extract fermented with A. oryzae GB107 could be used to control lipid accumulation in adipocytes.
Adipocytes*
;
Adipogenesis
;
Adiponectin
;
Aspergillus oryzae*
;
Glycerolphosphate Dehydrogenase
;
Leptin
;
Oryza
;
Soybeans*