Daminozide Enhances Vigor and Steviol Glycoside Yield of Stevia (Stevia rebaudiana Bert.) Propagated in the Temporary Immersion Bioreactor

Stevia (Stevia rebaudiana Bertoni) contains sweet compound widely used as natural sweetener, steviol glycoside (SG). SG is a diterpenoid secondary metabolite synthesized from ent-kaurenoic acid, the same precursor of Gibberellin (GA). Therefore, in this study, a GA inhibitor, Daminozide (0, 10, 20 ppm) was used to block ent-kaurenoic acid conversion towards GA synthesis in attempt to increase SG content of stevia propagated in Temporary Immersion Bioreactor (TIB). Daminozide in 10 mg/L was observed to be the optimum concentration which increased biomass weight and SG content (stevioside and rebaudioside A) up to 40%. The treatment also increased transcripts accumulation of genes enrolled in SG biosynthesis, such as SrKA13H, SrUGT85C2, and SrUGT76G1, indicating SG pathway become more active due to the inhibition of GA pathway. Furthermore, the inhibition of GA was also indicated by the upregulated expression of GA biosynthesis gene (GA3ox) as the result of feedback regulation, and the downregulated expression of GA catabolism gene (GA2ox2) as the result of feed-forward regulation caused by inhibitor treatment.

Ce:LaB3O6 glass for high-resolution radiation dosimetry

Ce:LaB3O6 (LBO) glass, whose constituents are abundant elements and fabrication is easy and cheap, is found to be a promising thermoluminescence (TL) dosimeter. This is originally achieved by CeF3 doping and melting under a reducing atmosphere, with the optimum concentration of 0.1% (quantum efficiency = 66%). The corresponding Ce interatomic distance is ~ 4 nm, below which concentration quenching occurs via Ce dipole-dipole interaction, as elucidated experimentally by Dexter’s theory. Ce:LBO exhibits a good dose resolution, with a linear dependence covering five orders of magnitude on both irradiation-dose and TL-response. Furthermore, it can be cyclically irradiated and read without degradation.

Application of Different Rates and Frequencies of Rejuvenator for the Treatments of Brown Bast Syndrome on Hevea brasiliensis

Background: Brown bast is one of the most serious threats to natural rubber production. It is estimated that brown bast leads to an approximately 15-20% decrease in latex yield production. There is currently no effective method to control this problem and an effort to overcome this problem is in progress by the natural rubber producing countries. Methods: This study evaluated the effect and the most suitable rate and frequency of Rejuvenator application to cure brown bast (latex dryness) and improve latex yield. The Rejuvenator treatment was applied to the selected tree with two different treatment frequencies (every 3 days and every 6 days) and three different Rejuvenator concentrations (5 g/L, 10 g/L and 5 g/L). The Rejuvenator was applied 5 times. Data on latex yield and brown bast cure were then recorded 1 month after the application of the last treatment. The treatments used were T1: No Rejuvenator, T2: 5 g/L of Rejuvenator, T3: 10 g/L of Rejuvenator, T4: 15 g/L of Rejuvenator. Result: Of all the treatment used, T3 (10 g/L) resulted in higher production of latex yield and Hevea bark nutrient concentration (g/t/t) than control. It also gave the highest nutrient content in the bark tissue. The findings of this study reveal that the optimum concentration and frequency of Rejuvenator application were established at 10 g/L every 6 days. More so, the findings explain that inadequate nutrients can be attributed to the brown bast syndrome in rubber plantation which can be prevented with the use of a rejuvenator to the tree’s bark.

Shellac dan Gelatin untuk Konsolidasi Artefak Kayu

Wood is a hygroscopic organic material, prone to damage and weathering, especially by humidity. The moisture in the wood will trigger biotic activities such as fungus, which can decompose of wood materials, that is, cellulose. Moreover, wood is susceptible to insect attacks such as termites. This condition will cause the wood to become brittle so that the strength of the wood will decrease. To strengthen brittle wood, consolidation treatments are needed. Material for wood consolidation that has been used is Paraloid B72 with acetone solvent, which is not easy to find everywhere Materials tested for wood artifacts consolidations were shellac and gelatin with a concentration of 5%, 7,5%, and 10%. As a comparison, the material used for wood consolidation is Paraloid B72 10%. Test parameters used include SEM test, density test, compressive strength test, color change test, fungal growth observation, and FTIR test. Test results have shown that shellac 7,5% and 10% can be an alternative to Paraloid B72 as a wood artifacts consolidation material. Shellac 7,5% is the optimum concentration for wood artifacts consolidation because materials will be more efficient. This material can fill the wood pores and increase the density by 13,89%. The resulting compressive strength value reached 248,01 kg/cm2 or increased by 43,18%, higher than Paraloid B72 10%. Shellac 7,5% does not change the color of the wood and safe from fungal growth when applied to wood. This material also does not change the chemical composition of wood. Keywords: wood, artifact, consolidation, shellac, gelatin, Paraloid B72

Antioxidant status, nutrition facts, and sensory of spinach extract fortified wet noodles

Healthy food has been a lifestyle trend in modern society since the last decades. Vegetable noodles as an alternative healthy food are often consumers’ choices considering that noodles are a favourite food today. This study aims to get more insight into the effect of spinach extract (SE) fortification on noodle dough toward antioxidant status, nutrition facts, and the sensory of wet spinach noodles (WSN) produced. The dough of wet noodle samples was treated by 4 different concentrations of SE fortification of 0, 0.4, 4.0, and 40 mg/mL in which for each treatment was quintuple. Results showed SE fortification had a significant effect on antioxidant status, some nutrient composition (protein, sugar, cholesterol, energy amount, iron, magnesium, and vitamin C), and sensory characteristics of the wet noodle. WSN with rich in antioxidants, low calories, and favoured by panellists was obtained at the optimum concentration of 4 mg/mL. Thus, SE was potential as food fortificant for developing WSN as a promising functional food product in the future.

Differences in the Effects of Calcium and Magnesium Ions on the Anammox Granular Properties to Alleviate Salinity Stress

Divalent cations were known to alleviate salinity stress on anammox bacteria. Understanding the mechanism of reducing the salinity stress on anammox granules is essential for the application of the anammox process for saline wastewater treatment. In this study, the effect of Ca2+ and Mg2+ augmentation on the recovery of the activity of freshwater anammox granules affected by salinity stress was evaluated. At the condition of a salinity stress of 5 g NaCl/L, the specific anammox activity (SAA) of the granule decreased to 50% of that of the SAA without NaCl treatment. Augmentation of Ca2+ at the optimum concentration of 200 mg/L increased the SAA up to 78% of the original activity, while the augmentation of Mg2+ at the optimum concentration of 70 mg/L increased the SAA up to 71%. EPS production in the granules was increased by the augmentation of divalent cations compared with the granules affected by salinity stress. In the soluble EPS, the ratio of protein to polysaccharides was higher in the granules augmented by Ca2+ than with Mg2+, and the functional groups of the EPS differed from each other. The amount of Na+ sequestered in the soluble EPS was increased by the augmentation of divalent cations, which seems to contribute to the alleviation of salinity stress. Ca. Kuenenia-like anammox bacteria, which were known to be salinity stress-tolerant, were predominant in the granules and there was no significant difference in the microbial community of the granules by the salinity stress treatment. Our results suggest that the alleviation effect of the divalent cations on the salinity stress on the anammox granules might be associated with the increased production of different EPS rather than in changes to the anammox bacteria.

Effect of Fetal Bovine Serum on the Sperm Quality of Depik (Rasbora tawarensis) after Short-term Cryopreservation

Background: Sperm cells are susceptible to oxidative stress during cryopreservation. Therefore, an antioxidant is necessary to protect them from damages. Fetal bovine serum (FBS) is one of potent antioxidants for fish sperm cryopreservation. Hence, the aims of this study are to examine the effect of FBS on sperm quality after a short period and to determine its optimum concentration on depik (Rasbora tawarensis). Methods: Depik fish were obtained from the Fish hatchery of Lukup Badak, Aceh Tengah District, Indonesia. Sperms collected from the fish were diluted in Ringer extenders containing FBS concentration of 10% (P1), 20% (P2), 30% (P3), 40% (P4), 50% (P5) and 60% (P6), filled into 2 ml cryotubes and equilibrated prior immersed into liquid nitrogen for 15 days. The parameters observed were sperm motility, consistency, pH, fertilization and hatching rates and DNA fragmentation post-thawing. Result: The ANOVA test indicates that the application of FBS in Ringer had a significant effect on sperm motility, fertilization and hatching rates (P less than 0.05). The highest motility (58.33%) was recorded at FBS 60% and significantly different from those at other concentrations. The laddering analysis showed that applying FBS protected the integrity of depik sperms DNA. It is concluded that the optimum concentration of FBS on depik sperm led to a short-term cryopreservation of 60%.

Expression of the recombinant C-terminal of the S1 domain and N-terminal of the S2 domain of the spike protein of porcine epidemic diarrhea virus

Background and Aim: Porcine epidemic diarrhea virus (PEDV) causes severe diarrhea in suckling piglets, leading to severe economic losses in the swine industry. Commercial vaccines have limited effectiveness against different genogroups of PEDV and the shedding of virus. The C-terminal of the S1 domain and the N-terminal of the S2 domain (S1-2) protein of the spike (S) protein have four neutralizing epitopes. However, research on the expression of the S1-2 segment of the S gene has been limited. In this study, we expressed a recombinant S1-2 protein of the S protein of the PEDV Thai isolate and characterized the immunological properties of the recombinant S1-2 protein. Materials and Methods: The S1-2 segment of the S gene of the PEDV Thai isolate (G2b) was amplified, cloned into the pBAD202/D-TOPO® vector (Invitrogen, Carlsbad, CA, USA), and expressed in Escherichia coli. The optimum concentration of arabinose and the optimum induction time for the expression of the recombinant S1-2 protein were determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The immunogenic reactivity of the recombinant S1-2 protein was determined using Western blot analysis with rabbit polyclonal antibodies against the SM98 strain of PEDV (G1a). Results: The recombinant S1-2 segment of the S gene of the PEDV Thai isolate protein was cloned and the recombinant S1-2 protein was successfully expressed. The optimum concentration of arabinose and the optimum induction time for the induction of the recombinant S1-2 protein were 0.2% and 8 h, respectively. The recombinant S1-2 protein reacted specifically with both rabbit anti-histidine polyclonal antibodies and rabbit anti-PEDV polyclonal antibodies. Conclusion: The recombinant S1-2 protein reacted with rabbit anti-PEDV polyclonal antibodies induced by the different PEDV genogroup. Therefore, the recombinant S1-2 protein may be a useful tool for the development of a diagnostic test for PEDV or for a vaccine against PEDV.

Recycling of Bagasse as an Agricultural Waste and its Effect as Filler on Some Mechanical and Physical Properties of SBR Composites

In the present study, a series of mixes based on different concentrations of carbon black (CB) as a reinforcing filler and sugarcane bagasse as supplementary filler, were investigated to examine their effects on the mechanical properties of styrene butadiene rubber (SBR) composites. To this end, the first group of mixes deals with the effect of different concentrations of CB ranging from 0 to 80 phr at fixed bagasse concentration of 25 phr. The second group of mixes involves the addition of bagasse with concentrations varying from 10 to 50 phr at 10 intervals with fixed CB concentration of 40 phr. The sizes of the employed ground bagasse powder (GBP) in all prepared formulations ranged from 20 to 180 μm. In addition, 2.5 phr of maleic anhydride (MA) was added to enhance the interfacial adhesion between SBR and agricultural waste fillers (i. e. bagasse). Tensile strength, elongation at break, modulus at 100% elongation, resilience, hardness (Shore A), abrasion and degree of swelling of the rubber vulcanizates were studied. The prepared samples were also analyzed by scanning electron microscopy (SEM) to show the distribution of fiber and the occurrence of fiber-matrix adhesion. The optimum concentration of bagasse to be used simultaneously with CB in SBR composites was found to be 30 phr. Overall, it was found from the obtained results that the addition of GBP up to 50 phr is feasible without impairing the mechanical properties of SBR vulcanizates.