Ruminal fermentation and microbial ecology of buffaloes and cattle fed the same diet

Although buffaloes and cattle are ruminants, their digestive capabilities and rumen microbial compositions are considered to be different. The purpose of this study was to compare the rumen microbial ecology of crossbred water buffaloes and cattle that were fed the same diet. Cattle exhibited a higher fermentation rate than buffaloes. Methane production and methanogen density were lower in buffaloes. Phylogenetic analysis of Fibrobacter succinogenes‐specific 16S ribosomal RNA gene clone library showed that the diversity of groups within a species was significantly different (P < 0.05) between buffalo and cattle and most of the clones were affiliated with group 2 of the species. Population densities of F. succinogenes, Ruminococcus albus and R. flavefaciens were higher until 6 h post‐feeding in cattle; however, buffaloes exhibited different traits. The population of anaerobic fungi decreased at 3 h in cattle compared to buffaloes and was similar at 0 h and 6 h. The diversity profiles of bacteria and fungi were similar in the two species. The present study showed that the profiles of the fermentation process, microbial population and diversity were similar in crossbred water buffaloes and crossbred cattle.     

Implications of static in vitro digestion of starch in the presence of dietary fiber

Interest in understanding the digestion behavior of starch in the presence of dietary fibers is growing due to the ability of dietary component to control the release and absorption of glucose. This presents an outstanding opportunity to improve the quality of food products by incorporating dietary fiber into starchy food products. The physicochemical properties of different fibers and their behavior in the gastrointestinal tract (GIT) differ. To test the efficacy of these different fibers on starch digestion, static in vitro digestion models under conditions that mimic the human GIT are frequently used. Indeed, many efforts have been committed to the development of various static in vitro protocols for starch digestion. Though not considered as the gold standard in digestibility studies in food science and technology, static simulated models provide a useful alternative to in vivo techniques for rapid screening of the digestibility of food products under conditions that simulate the human GIT. This review presents the current status and development of digestion techniques for simulating digestion conditions in the human GIT, with particular interest on starch digestion in the presence of dietary fiber in the three phases of digestions including the oral, gastric and the intestinal steps. This summary can benefit investigators in developing static in vitro digestion models designed to simulate starch digestion with relevant values of the quantifiable parameters, including pH, enzymes and simulated digestive fluids.     

Marker assisted backcross breeding to improve cooking quality traits in Myanmar rice cultivar Manawthukha

Several components contribute to rice grain quality, and among these, fragrance and taste qualities are the most important to consumers. Manawthukha, an elite non-fragrant cultivar with high amylose content (AC), intermediate gel consistency (GC) and gelatinisation temperature (GT), occupies the largest number of acres in Myanmar. To improve fragrance and intermediate AC in Manawthukha, Basmati370 was used as a donor parent to introgress the Basmati alleles of genes conferring fragrance and intermediate AC into Manawthukha by Marker Assisted Backcrossing (MAB). Four backcrosses and one selfing were conducted to transfer positive alleles of badh2 and Wx from Basmati into Manawthukha. Twelve BC₄F₂ selected lines that carried the homozygous Basmati alleles were planted in multi-location trials (four in Myanmar and one in Thailand) and examined for their agronomic performance and cooking quality. The seeds of the improved lines and their parents, harvested from Kamphaeng Saen, Kuaukse, Kyauktada and Latpatan, were investigated for fragrance and AC. All improved lines had fragrance and intermediate AC similar to the donor parent Basmati, whereas their agronomic performances were the same as the original Manawthukha. All improved lines had medium plant heights, high tiller numbers, dense panicles, non-lodging phenotypes and high yielding potentials. Simultaneous improvement of fragrance and intermediate AC indicated that badh2 and Wx genes had major effects on the fragrance and AC, respectively. We show here the success of improving fragrance and intermediate AC by MAB and the high efficiency of selection in early generations. In the present study, MAB accelerated the development of superior qualities in the genetic background of Manawthukha. The improved Manawthukha should be immediately useful for Myanmar farmers and will help farmers to increase their incomes.     

Role of acidification elicited by sialylation and sulfation of zona glycoproteins during oocyte maturation in porcine sperm-zona pellucida interactions

The porcine zona pellucida (ZP) undergoes biochemical changes during the final phase of maturation prior to fertilization. The present study was conducted to elucidate whether the acidification of ZP glycoproteins during porcine oocyte maturation influences sperm-ZP interactions. Two-dimensional gel electrophoresis clearly demonstrated that ZP acidification occurred in accordance with the sialylation and sulfation of ZP glycoproteins in oocytes matured for 44 h. The increases in the incidences of sperm penetration and polyspermy with the progress of the IVM culture period were significantly suppressed by ZP desialylation on treatment with neuraminidase as a consequence of reductions in the number of sperm bound to ZPs and the acrosome reaction (AR) in ZP-bound sperm (P<0.05). In contrast, the blocking of ZP sulfation by NaClO(3) treatment during IVM markedly reduced the incidence of polyspermy with no inhibitory effect on penetration, but the number of sperm bound to ZPs and the rate of AR-inducing sperm were decreased to the same level as in desialylated oocytes. The results indicate that ZP sulfation influences sperm-ZP interactions in a ZP sialylation-independent manner. Moreover, sialylation and sulfation were not associated with a protective proteolytic modification of the ZP matrix before fertilization. These findings suggest that ZP acidification elicited by the sialylation and sulfation of ZP glycoproteins during oocyte maturation contributes to the porcine ZP acquiring the capacity to accept sperm.     

Evaluation of effective Myanmar Bradyrhizobium strains isolated from Myanmar soybean and effects of coinoculation with Streptomyces griseoflavus P4 for nitrogen fixation

In order to substitute the use of chemical fertilizers in legume production, there is a need for the production of rhizobial inoculants which are capable of being used as biofertilizers. To achieve this, an effective symbiotic nitrogen (N) fixation between legumes and root nodule bacteria will be essential. Evaluation of effective Myanmar Bradyrhizobium (Jordan 1982) strains isolated from Myanmar soybean (Glycine max L. Merr.) and effects of coinoculation with Streptomyces griseoflavus Krainsky 1914 P4 for N fixation were studied in pot experiments using sterilized vermiculite and Hoagland solution in the Phytotron (25°C and 70% relative humidity) with completely randomized design and three replicates. N fixation ability of soybean was evaluated by acetylene reduction activity (ARA) by gas chromatography. It was found that MAS23 showed a relatively high degree of stability and a high level of ARA per plant on both Yezin-3 and Yezin-6 soybean varieties. In the symbiotic relationship between Bradyrhizobium strains and P4 experiments, the treatments consisted of six Bradyrhizobium strains (MAS23, MAS33, MAS34, MAS43, MAS48 and USDA110) and Streptomyces griseoflavus P4 were evaluated with four Myanmar soybean varieties (Yezin-3, Yezin-6, Hinthada and Shan Sein). In the Yezin-3 soybean variety, the best treatment for ARA per plant was found in the dual inoculation of P4 and MAS34. In the Yezin-6 soybean variety, the highest nodule dry weight was found in dual inoculation of P4 with MAS34 but the highest ARA per plant was observed in the dual inoculation of P4 and MAS23. On the other hand, single inoculation of MAS43 and coinoculation of P4 with MAS48 were significantly higher in N fixation of Hinthada, and coinoculation of P4 with MAS33 was significant improvement of ARA per plant (P < 0.05) in Shan Sein soybean.     

Improved purity and immunostimulatory activity of β-(1→3)(1→6)-glucan from Pleurotus sajor-caju using cell wall-degrading enzymes

The objective of this work was to improve the purity of β-(1→3)(1→6)-glucan in the native triple helical structure from the fruiting bodies of Pleurotus sajor-caju for effective biological function using cell wall-degrading enzymes. A crude carbohydrate was extracted with hot water, then treated with crude xylanase and cellulase from Paenibacillus curdlanolyticus B-6. β-Glucan in the extract was purified to homogeneity with a single and symmetrical peak using 650M DEAE Toyopearl and Sepharose CL-6B column chromatography. The purity of β-glucan was confirmed by high-performance size-exclusion chromatography. Purified β-glucan was obtained at a purity of up to 90.2%. The Congo red reaction and atomic force microscopy indicated that the purified β-glucan exhibited a triple helix conformation. Purified β-glucan was able to effectively up-regulate the functions of macrophages such as nitric oxide (NO) and tumor necrosis factor (TNF-α) production.     

Characterization of Myanmar Paw San Hmwe Accessions Using Functional Genetic Markers

Paw San Hmwe(PSM) rice has been cultivated in many areas of Myanmar for a long time. Strong aroma,good taste and its elongation during cooking are the key characteristics of PSM rice. Thirty-one PSM accessions were genotypically characterized,and their physical grain and cooking quality traits were studied. We used specific gene markers associated with aroma,apparent amylose content(AAC) and alkali spreading value to determine the alleles carried by different PSM accessions. The results revealed that six PSM accessions(PSM10,PSM12,PSM13,PSM21,PSM22 and PSM30) had a 3-bp insertion in Os2 AP gene. Gel consistency(GC) allele was predominant among the PSM accessions for gelatinization temperature(GT),however,the phenotype observed was between low and intermediate GT because of the combination of the GC allele with the presence of low GT allele at heterozygous state from the other loci of the SSIIa gene. Intermediate to high AAC was observed among the PSM accessions corresponding to the haplotype identified for the single nucleotide polymorphism G/T and the(CT)n repeat in the Wx gene. The characterization and grouping data of PSM accessions posted benefits to Myanmar seed banks,and our results will help in maintaining the integrity of PSM rice variety.     

Microbiological properties of Myanmar traditional shrimp sauce,hmyin-ngan-pya-ye

Fisheries Science - The microbiological properties of Myanmar traditional fermented products were characterized using four different brands of bottled shrimp sauce products sold frequently at a...