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An automatic bulk monitoring and aeration controller was programmed with an adsorption equilibrium absolute humidity (CAE)equation and was used to aerate paddy with the aim to increase moisture content (MC) and preventing fissuring. The ventilation control window for rewetting paddy was developed according to two conditions: (i) the average grain bulk temperature (tg) is higher than the dewpoint temperature (DPTa) of the atmosphere; and (ii) the equilibrium absolute humidity (EAHg) of grain moisture content plus 1 percentage point is lower than the absolute humidity (AHa) of the atmosphere. The ventilators were turned on when the atmosphere state point was within the ventilation windowand turned off outside that window. In a humid subtropical monsoon climate, during Oct. 8th to Nov. 1st, 2013, the system was used for a paddy depot of 1035 t in Dianjiang, Chongqing province. The natural humid air was introduced into the paddy bulk by negative pressure suction aeration during the 10-12 h night time period and allowed to equilibrate with grain kernels during the 12-14 h day time period. Aeration increased grain MC by 0.6 percentage points with two 1.5 kW axial flow ventilators and power consumption of 209 kW·h. The unit energy consumption was 0.336 KW·h (1% moisture·t)-1. The broken milled rice percentage was decreased by 2-3 percentage points. In the warm temperate semi-humid monsoon climate, during April 13th to June 16th, 2017, the system was used to rewet japonic paddy in a 2489 t depot in Qihe, Shandong province. The conditions for running two 0.85 kW axial flow fans were: (i) when the atmosphere relative humidity (RHa) is ≤80% and its temperature (ta) is DPTa, and EAHg80% and ta 28°C, the two fans were switched off. This rewetting aeration increased grain MC from 13.5% to 14.0%, and the unit energy consumption was 0.455 kW·h (1% moisture·t)-1. The percentages of average head rice yield and damaged grains after aeration were 71.7% and 7.7%, respectively.

Due to the impact of global environment and climate change, determining how to ensure food production and reduce food loss has become an important research topic for many countries, especially developing countries, and can provide key information for China's grain harvest management. This article mainly examines the impact of harvesting period on rice yield, the existence of latent losses, and their management value. From 2019 to 2022, our team conducted experiments on the growth curve of rice grains, plants, and populations to investigate the existence of latent losses by establishing the relationship between the standard moisture weight and the days after heading. The results showed that the weight of the rice gradually decreased as the harvest time was delayed, and there were latent losses, of which the dry matter loss was about 3.5%. With the addition of grain shattering loss, the latent loss rate was about 7.0%. In summary, if rice management is strengthened, including harvesting at the optimal time, 4.67% of the loss can be recovered. The timing of the harvest significantly impacts rice yield. Understanding the process and causes of new types of rice losses, increasing the basis for judging the timely harvest period, and providing the best management measures can prevent the post-harvest losses caused by traditional methods and increase the amount of fertile land available. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA) is widely found in food and feed products as a mycotoxin contaminant. It is produced byPenicilliumspecies and severalAspergillusspecies. The identification OTA detoxification microorganisms is believed to be the best approach for decontamination. In this study, we isolated ASAG1, a bacterium with the ability to degrade OTA effectively, from grain depot-stored maize. A 16S rDNA sequencing approach was used to identify this strain asBacillus amyloliquefaciensASAG1. The degradation of OTA was detected in both medium and cell-free extracts after incubation with a culture ofB. amyloliquefaciensASAG1 cells. Subsequently, a hydrolysed enzyme (carboxypeptidase) related to the enzymatic conversion of OTA was cloned from theB. amyloliquefaciensASAG1 genome. Using theEscherichia coliExpression System, we successfully expressed and purified this carboxypeptidase. When this enzyme was incubated with the engineered recombinantE. colicells, the concentration of OTA was dramatically degraded. Our data therefore indicate that the carboxypeptidase produced byB. amyloliquefaciensASAG1 is likely responsible for the biodegradation of OTA. [ABSTRACT FROM PUBLISHER]

Grain storage has very important effects on national security and has been given increasing attentions at past several decades. Condensation is one of the main dangers to the grain storage safety. Temperature, moisture and warehouse type are the three most important factors to form condensation. However, it is very difficult to study the effects of temperature and moisture on the grain storage safety in the actual granary due to the huge cost. So, it is a good choice by building models to forecast the changes of temperature or humidity in the granary by experiments. At present, the studies were still at the middle-small experimental stages in the domestic and overseas. Due to the differences of climate, long storage period and warehouse types at different regions, it is more difficult to build the universal temperature or humidity models in China than other nations. To explore the condensation processes, wheat were storage in steel squat silo and horizontal bin located in Tianjin District respectively, which were used widely to store grain in China. The changes of temperature and water vapor pressure of the wheat in spring, summer and winter were researched in the paper. The grain temperature data in different seasons was obtained by sensors array. Second Newton interpolation method was used to obtain the fitting algorithm of temperature. The data of wheat water vapor pressure was figured out by WU model. The temperature fields and the water vapor pressure field of the wheat in two researched storehouse were reproduced by MATLAB software, respectively. Then, the cloud maps were analyzed according to the coupling principle of temperature and water vapor pressure fields and WU model. The results showed that a large cold area existed in the wheat in the steel squat silo or the horizontal bin in summer, which could be the main reason of non-dewfall and resulted in a storage safety. A multi-level water vapor pressure zone, which was defined as the low-water vapor pressure area and high-ones alternately appeared in the stored wheat, all was observed in the wheat in the steel squat silo and the horizontal bin during late winter to early spring. More significant multi-level water vapor pressure zone (which suggested a larger gradient of grain temperature and water vapor pressure) and more moisture absorbed rate of the surface grain than that of the horizontal bin resulted in the condensation on the surface occurred more easily in the steel squat silo in early spring, which suggested a storage risk of the wheat in spring. The isotherm was different remarkably between the two warehouses. In the steel squat silo, the isotherm was closed, but it presented non-closed in the horizontal bin. Based on the change direction of isothermal curve, it could deduce that there was another horizontal bin bordered. Additionally, the isotherms of the two horizontal bins could close well from the temperature field cloud maps, which suggested grain stored in the bordered horizontal bin. The results were in consistent with the actual. They provided not only new thought of forecasting condensation, but also new perspective of making inventories of warehouses. [ABSTRACT FROM AUTHOR]

l-cysteine is an important sulfur-containing α-amino acid. It exhibits multiple physiological functions with diverse applications in pharmaceutical cosmetics and food industry. Here, a strategy of coordinated gene expression between carbon and sulfur modules in Escherichia coli was proposed and conducted for the production of l-cysteine. Initially, the titer of l-cysteine was improved to (0.38±0.02) g/L from zero by enhancing the biosynthesis of l-serine module ( serA f , serB and serC Cg ) and overexpression of CysB. Then, promotion of l-cysteine transporter, increased assimilation of sulfur, reduction or deletion of l-cysteine and l-serine degradation pathway and enhanced expression of cysE f (encoding serine acetyltransferase) and cysB St (encoding transcriptional dual regulator CysB) were achieved, resulting in an improved l-cysteine titer (3.82±0.01) g/L. Subsequently, expressions of cysM , nrdH , cysK and cysIJ genes that were involved in sulfur module were regulated synergistically with carbon module combined with utilization of sulfate and thiosulfate, resulting in a strain producing (4.17±0.07) g/L l-cysteine in flask shake and (11.94±0.1) g/L l-cysteine in 2 L bioreactor. Our results indicated that efficient biosynthesis of l-cysteine could be achieved by a proportional supply of sulfur and carbon in vivo . This study would facilitate the commercial bioproduction of l-cysteine.

For the wise use of fungal biocontrol and metalaxyl fungicide, starch-alginate-based formulations have been developed by encapsulating metalaxyl and non-toxigenic Aspergillus flavus spores simultaneously in the form of microspheres using calcium chloride as a cross-linking agent. The formulations were characterized by Fourier transform infrared spectroscopy (FTIR), a scanning electron micrograph (SEM), and thermogravimetry (TGA). Formulation characteristics, including the bead size, entrapment efficiency, swelling ratio of the beads, and rheological properties, were analyzed. The release behavior of beads with different formulations was evaluated. The addition of kaolin and rice husk powder in starch-alginate beads retarded the release profile of spores and metalaxyl. The release of the active ingredient from starch-alginate-kaolin beads and starch-alginate-rice husk powder beads occurred in both a controlled and sustained manner. Additionally, the release rate decreased with the increase of kaolin or rice husk powder content. The beads added with kaolin were slower than the release of rice husk powder. In comparison, spores released slower and lasted longer than metalaxyl. The starch-alginate-kaolin formulations could be used as controlled release material in the field of biocontrol and reduce the harm of fungicides to the environment., Competing Interests: The authors declare no conflict of interest.