In order to meet the market demand and avoid the increase of operation amount and cleaning cost in the process of ultrafiltration, it is particularly important to find more practical and efficient methods to control and improve membrane fouling. In this study, the ions in the ultrafiltration process were regulated to affect membrane surface proteins composition (lactoferrin, α-lactalbumin, β-lactoglobulin A and β-lactoglobulin B) and delay membrane fouling. It was found that Na+ (21 mmol/L), Zn2+ (0.25 mmol/L) and K+ (44 mmol/L) was added at 4 min, 8 min and 12 min, respectively during ultrafiltration process. The continuous regulation slowed down the decline rate of membrane flux and reduced the content of α-lactalbumin, β-lactoglobulin A and β-lactoglobulin B on the membrane surface analyzed by HPLC. This could reduce the irreversible membrane fouling of proteins cake resistance. Furthermore, the ions concentration was also investigated after filtration. The concentration of K+ was increased significantly and other ions concentration was not significantly changed after continuous regulation such Na+, Mg2+, Zn2+ and Ca2+ compared to control. Therefore, dynamic ionic regulation of whey protein ultrafiltration process is a simple and effective method, which provides technical theoretical basis for optimizing and improving membrane technology.

Salinity is a worldwide problem limiting the plant growth and risking food security. This study was conducted to examine exogenous application of silicon (Si), gibberellic acid (GA3) upon the ion transport, growth, yield, and antioxidant enzymes activities of pea plant in saline conditions. Two pea varieties Meteor-FSD and Samrina Zard were pre-treated with GA3 (10-4 M) for 12 h. Plants were allowed to grow with or without silicon in washed silica sand. Ten days old seedlings were shifted in pots with 10 kg soil. Twenty-five days old plants were exposed to 0 and 5 dS m-1 sodium stress. Results showed that exogenous application of GA3 + Si was the best treatment for increasing plant biomass and yield in the presence and absence of NaCl. Furthermore, application of Si or GA3 enhanced chlorophyll content in the leaves, thereby increasing the net assimilation rate of pea varieties under NaCl stress by increasing the antioxidant enzyme activity. Treatment of Si alone or in combination with GA3 significantly reduced Na+ movement in both pea varieties. Results showed that Si has more prominent role than GA3 alone to build-up high plant biomass, yield, soluble protein content and reduction of Na+ transport. Samrina Zard variety showed higher yield, shoot and root dry weight as compared to Meteor-FSD variety in presence and absence of salt. It was concluded that Si can be used as a nutrient for pea under saline or non-saline conditions. Moreover, application of GA3 has a potential role for increasing salinity tolerance, mostly in sensitive pea varieties.

OBJECTIVE: Plant beneficial rhizobacteria (PBR) improve salt tolerance and plant yield in vegetable plants by producing 1-aminocyclopropane-1-carboxylate-deaminase, indole-3-acetic acid and phosphate solubilization. Organic-based carrier material is needed to ensure the PBR\'s uniform application, distribution, survival and functioning in a variety of fields. The PBR also use carbon present in the carrier as food and energy source. The selection of a suitable organic-based carrier material for the application of the PBR in normal and saline soils always has received less attention. The current study compared the PBR suitability of different organic-based carrier materials (biochar, biogas residues [BGRs] and coconut powder) and evaluated their effects on okra productivity under normal and saline soil conditions.
RESULTS: In a pot experiment, the PBR strain Bacillus sp. MR-1/2 (accession number, MG548383) was applied with/or without organic-based carrier materials to okra grown in three different soils: S1 (EC 1.0 dS m-1 ), S2 (EC 3.0 dS m-1 ) and S3 (EC 5.0 dS m-1 ). The experiment was set up in a completely randomized design with five replicates in factorial arrangement. Results indicated that in soil S1, PBR + BGR increased the number of pods per plant, plant dry weight and indole compounds by 64%, 68% and 17% while reduced the electrolyte leakage (ELL), malonaldehyde (MDA) contents and stress ethylene level by 17%, 55% and 38%, respectively over the PBR application without any carrier. Similarly, in soil S2, the treatment PBR + BGR increased the number of pods by 81%, plant dry weight by 40% and indole compounds by 13% while reduced the ELL by 17%, MDA contents by 50% and stress ethylene by 30% over the PBR alone treatment. In soil S3, PBR + biochar increased the number of pods by 51%, plant dry weight by 62% and indole compounds by 20%, while reduced the ELL by 21%, MDA by 40% and indole compounds by 54% over the PBR alone treatment.
CONCLUSIONS: Results concluded that in soil S1 and S2 (normal soils), BGR as carrier for PBR showed best results, while in soil S3, biochar as carrier for PBR resulted in enhanced potassium (K+ ) and calcium (Ca+2 ) uptake and increased the productivity of okra.
CONCLUSIONS: Response of different carrier materials in supporting PBR under different soil conditions was variable. This study will help in the selection and use of best suitable carrier material for PBR application under different soil conditions. It is recommended that farmer should use BGR as carrier material for PBR application in normal soils while biochar should be used as carrier for the PBR application in saline soil.

The effects of exogenous trehalose (Tre) on salt tolerance of pharmaceutical plant Catharanthus roseus and the physiological mechanisms were both investigated in this study. The results showed that the supplement of Tre in saline condition (250 mM NaCl) largely alleviated the inhibitory effects of salinity on plant growth, namely biomass accumulation and total leaf area per plant. In this saline condition, the decreased level of relative water content (RWC) and photosynthetic rate were also greatly rescued by exogenous Tre. This improved performance of plants under high salinity induced by Tre could be partly ascribed to its ability to decrease accumulation of sodium, and increase potassium in leaves. The exogenous Tre led to high levels of fructose, glucose, sucrose and Tre inside the salt-stressed plants during whole the three-week treatment. The major free amino acids such as proline, arginine, threonine and glutamate were also largely elevated in the first two-week course of treatment with Tre in saline solution. It was proposed here that Tre might act as signal to make the salt-stressed plants actively increase internal compatible solutes, including soluble sugars and free amino acids, to control water loss, leaf gas exchange and ionic flow at the onset of salt stress. The application of Tre in saline condition also promoted the accumulation of alkaloids. The regulatory role of Tre in improving salt tolerance was optimal with an exogenous concentration of 10 mM Tre. Larger concentrations of Tre were supra-optimum and adversely affected plant growth.