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Summary: Plants employ an array of intricate and hierarchical signaling cascades to perceive and transduce informational cues to synchronize and tailor adaptive responses. Systemic stress response (SSR) is a recognized complex signaling and response network quintessential to plant's local and distal responses to environmental triggers; however, the identity of the initiating signals has remained fragmented.Here, we show that both biotic (aphids and viral pathogens) and abiotic (high light and wounding) stresses induce accumulation of the plastidial‐retrograde‐signaling metabolite methylerythritol cyclodiphosphate (MEcPP), leading to reduction of the phytohormone auxin and the subsequent decreased expression of the phosphatase PP2C.D1.This enables phosphorylation of mitogen‐activated protein kinases 3/6 and the consequential induction of the downstream events ultimately, resulting in biosynthesis of the two SSR priming metabolites pipecolic acid and N‐hydroxy‐pipecolic acid.This work identifies plastids as a major initiation site, and the plastidial retrograde signal MEcPP as an initiator of a multicomponent signaling cascade potentiating the biosynthesis of SSR activators, in response to biotic and abiotic triggers. [ABSTRACT FROM AUTHOR]

Two medicinal plants, African Locust Bean (Parkia biglobosa) and Lonicera japonica, traditionally used in West Africa and China were investigated against four spoilage microorganisms: Bacillus subtilis, Cronobacter dublinensis, Pantoea agglomerans, and Bacillus sp., isolated from mulberry fruit. The aqueous extract of the P. biglobosa (ALB) was potent with average inhibitory zones against four spoilage microorganisms recorded as (Means ± SD) 6.5 to 19.5 mm as well as 6.5 to 15.5 mm for L. japonica (HSF) at concentrations of 400 mg/ml. The aqueous extracts of P. biglobosa (54%) inhibited decay better than L. japonica (66%). Decay situations of the medicinal plants with 1‐MCP emerged higher than the control group 78%, 72%, and 68% in ALB + 1‐MCP, HSF + 1‐MCP, and deionized water, respectively. Therefore, two plant extracts against spoilage microorganisms isolated from mulberry fruit had good inhibitory activities, but their mixture with 1‐MCP could not preserve the mulberry fruits in limited storage time. Practical applications: Advance in the bacteria control using a natural control like medicinal plants against plant infections was investigated. The present study demonstrated the potentials of African locust bean and L. japonica as a novel biocontrol agent to the extent of preserving the postharvest decay of mulberry fruit in limited storage time at room temperature. The results and findings obtained in this study support the potential application of these two plants in mulberry fruit preservation as well as in traditional therapeutics. In addition, the combination with 1‐MCP also serves as the potential to extend the shelf life of mulberry fruit in order to limit the use of pesticides in postharvest treatments. This study reports for the first time isolated microorganisms from mulberry fruit and the developments of edible coatings utilizing plant extracts from different continents against their activities. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: The preharvest application of Ca‐containing foliar fertilizers can reduce the incidence of bitter pit (BP) in apples and improve fruit quality by increasing the Ca content and decreasing both the N content and the N/Ca ratio in fruits. In this study, we aimed to investigate the control efficacy of Ca‐containing fertilizers on the incidence of BP and their effects on the Ca and N contents in bagged ‘Fuji’ apples by spraying foliar fertilizer containing calcium chloride (CaCl2), calcium nitrate [Ca(NO3)2] or calcium formate [Ca(HCOO)2] at an early stage, five days after full bloom (DAFB) and 40 DAFB, and at a late stage, 80 DAFB and 125 DAFB. RESULTS: The incidences of BP were reduced significantly by 43.2–73.0%, and the efficacy of spraying at an early stage was significantly higher than that of spraying at a late stage. The Ca content of bagged apple fruits increased whereas the N content and N/Ca ratio decreased after spraying Ca‐containing foliar fertilizers; however, the Ca content, N content and N/Ca ratio of apple leaves were differentially influenced. CONCLUSION: Foliar fertilizer containing CaCl2, Ca(NO3)2 or Ca(HCOO)2 can be used at an early stage to control BP in apple and improve the quality of bagged apple fruits. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Highlights • Membrane Contact Sites (MCS) as interfaces for interorganellar communication. • MCSs enable differential intracellular lipid distribution. • MCSs facilitate Ca2+ homeostasis, a conserved signaling agent. Cellular adaptive responses arise from an array of spatially and temporally distinct biochemical interactions that modulate biological processes and reorganize subcellular structures tailored to the nature of stimulus. As such, cells have evolved elegantly and tightly regulated mechanisms to enable interorganellar communication in part through the dynamic readjustment of physical distance enabling the tethering between two closely apposed membranous organelles and thus formation of Membrane Contact Sites (MCSs). MCSs are dynamic and ubiquitous interorganellar structures that serve as regulatory interfaces to facilitate transmission of signals and to integrate synthesis of metabolic pathways such as lipids required for upholding cellular homeostasis in response to environmental and developmental inputs. Endoplasmic reticulum (ER) is the most copious endomembrane system that extend throughout the cell, and functions in production, processing, and transport of proteins and lipids, as well as in intracellular signaling. Reminiscent of the ancient Silk Road, ER connection to other membranous organelles via MCSs alters cellular landscape and serves as nexus for coordinating exchange of metabolites such as lipids, ions such as Ca2+, and other small molecules involved in maintaining cellular integrity under prevailing conditions. Delineating the molecular organization of the tethering complexes, molecular action of exchanged molecules and hence the nature of information transmitted will afford insight into underlying basis of interorganellar communication and shed light on the evolutionarily conserved function of ER as the ancient trans-kingdom Silk Road trafficking vital metabolites via the non-vesicular pathway. [ABSTRACT FROM AUTHOR]

Plants have evolved tightly regulated signaling networks to respond and adapt to environmental perturbations, but the nature of the signaling hub(s) involved have remained an enigma. We have previously established that methylerythritol cyclodiphosphate (MEcPP), a precursor of plastidial isoprenoids and a stress-specific retrograde signaling metabolite, enables cellular readjustments for high-order adaptive functions. Here, we specifically show that MEcPP promotes two Brassicaceae-specific traits, namely endoplasmic reticulum (ER) body formation and induction of indole glucosinolate (IGs) metabolism selectively, via transcriptional regulation of key regulators NAI1 for ER body formation and MYB51/122 for IGs biosynthesis). The specificity of MEcPP is further confirmed by the lack of induction of wound-inducible ER body genes as well as IGs by other altered methylerythritol phosphate pathway enzymes. Genetic analyses revealed MEcPP-mediated COI1-dependent induction of these traits. Moreover, MEcPP signaling integrates the biosynthesis and hydrolysis of IGs through induction of nitrile-specifier protein1 and reduction of the suppressor, ESM1 , and production of simple nitriles as the bioactive end product. The findings position the plastidial metabolite, MEcPP, as the initiation hub, transducing signals to adjust the activity of hard-wired gene circuitry to expand phytochemical diversity and alter the associated subcellular structure required for functionality of the secondary metabolites, thereby tailoring plant stress responses. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new enzyme-assisted aqueous extraction with CNPs@Cu-Trypsin (CAE) was proposed. • Catalytic reinforcement of Cu2+ on the trypsin immobilized on CNPs was firstly revealed. • Hydrolysis activity and K cat / K m value of the new catalyst was increased by 6.16 and 1.7 times. • The CAE technique simultaneously utilizes oil and protein from biomass without solvents. • The CAE technique ensured products quality and the new catalyst can be reused ten times. Edible insects are rich in oil and protein resources, and has it become increasingly important to develop them reasonably when resources are increasingly scarce. However, due to the challenges in recovering enzymes in the enzyme-assisted aqueous extraction technique and the remaining organic solvents in the extraction process based on organic solvent, it is difficult to achieve simultaneous utilization of oil and protein from edible insects. Hence, an improved enzyme-assisted aqueous extraction process based on the assistance of chitosan cross-linked Fe 3 O 4 nanoparticles (CNPs) immobilized enzymes and divalent copper ions chelation, CNPs@Cu-Trypsin-assisted aqueous extraction technique, was first proposed. The hydrolysis activity was significantly increased by 6.16 times, and the value of K cat / K m was increased by 1.7 times for the results of the formation of the hydrophilic microenvironment. Furthermore, the extraction ratio of silkworm pupae oil extracted via CNPs@Cu-Trypsin-assisted aqueous extraction technique could be increased to 93%, and the oil extraction rate could be maintained above 65% after 10 times reused. Improvement of enzyme-assisted aqueous extraction under the addition of divalent copper ions could achieve an ideal effect of oil extracted from silkworm pupae with less time. Additionally, the quality of silkworm pupae oil was significantly improved and the silkworm pupae protein hydrolysate also showed improved biological activity. Therefore, the enzyme-assisted aqueous extraction enhancement by trypsin immobilization and divalent copper ion chelation is a promising strategy for the green and sustainable exploration of edible insect oil and protein without the use of organic solvents. [ABSTRACT FROM AUTHOR]

Interorganellar cooperation maintained via exquisitely controlled retrograde-signaling pathways is an evolutionary necessity for maintenance of cellular homeostasis. This signaling feature has therefore attracted much research attention aimed at improving understanding of the nature of these communication signals, how the signals are sensed, and ultimately the mechanism by which they integrate targeted processes that collectively culminate in organellar cooperativity. The answers to these questions will provide insight into how retrograde-signal-mediated regulatory mechanisms are recruited and which biological processes are targeted, and will advance our understanding of how organisms balance metabolic investments in growth against adaptation to environmental stress. This review summarizes the present understanding of the nature and the functional complexity of retrograde signals as integrators of interorganellar communication and orchestrators of plant development, and offers a perspective on the future of this critical and dynamic area of research. [ABSTRACT FROM AUTHOR]

The pupae is one of the most valuable components of the silkworm, a by-product of silk reeling. Employing them as a raw material to create valued products will help to recycle and reuse silkworm pupae, as well as contribute to the food industry's long-term development. Silkworm pupae protein (SPP) and pupae oil (SPO) are high in nutritional and bioactive components that have a variety of applications in the food industry as well as health-promoting characteristics. In this review, we first elaborate on the modification, nutritional, and functional properties of silkworm pupae in terms of requirements for protein and lipids processing as well as current extraction technology. In the subsequent sections, we summarize the modification techniques including the science and technology involved in attaining fatty acid components of SPO. Finally, we focus on recent studies related to the utilization of SPP and SPO subject to their inclusion in foods for their health benefits. The key to silkworm pupae product design may be to fully exploit and utilize the inherent characteristics of the pupae to produce functional peptides and structural lipids with high nutritional content, which may necessitate further improvements in the bioactive and functional properties. Designing more ecologically friendly, low-cost, and efficient processes for producing protein and oil from silkworm pupae is also a trend in technology. This may further provide new insights into the mechanisms behind modifying silkworm pupae as food and its health advantages. [Display omitted] • Modifications and functions of silkworm pupae protein (SPP) and oil (SPO) were reviewed. • Modification of SPP and SPO reveal valuable nutritional properties. • Inclusion of SPP and SPO in food and feed applications were summarized. • Peptide composition in silkworm pupae aid in valuable biological activities. • Further research to compare SPP and SPO with standard proteins and oils is recommended. [ABSTRACT FROM AUTHOR]

The reaction can be scaled up. [ABSTRACT FROM AUTHOR]

• Mulberry anthocyanins were prepared by ATPS biotransformation and HPLC purification. • An ATPS was designed to enhance the conversion of mulberry red pigment from C 3 R to C 3 G. • Whole-cell catalysts containing α -rhamnosidase at the interface of ATPS for easy recovery. • Peak partition collection and post-processing of semi-preparative HPLC was established. • The final purities of C 3 G and C 3 R prepared by semi-preparative HPLC reached 99 %. As a nutritious fruit, mulberry is an ideal source of high-quality cyanidin-3- O -glucoside (C 3 G) with various biological activities. However, the difficult separation process of high-purity C 3 G leads to its high price. To rapidly prepare high-purity C 3 G, cyanidin-3- O -rutinoside is converted to C 3 G by direct hydrolysis of rhamnose bond using a whole-cell catalyst containing α -rhamnosidase. Combined with an aqueous two-phase system, a coupling reaction separation system was established. Two monomers were successfully separated by semi-preparative high performance liquid chromatography (semi-preparative HPLC). The conversion of C 3 G catalyzed by whole-cells in the PEG/Na 2 SO 4 system increased from 47.11 % to 66.56 %, compared with the EtOH/(NH 4) 2 SO 4 system, and the whole-cell activity remained above 50 % after five rounds of reuse. Meanwhile, the purity of C 3 G was increased to 99 % via the semi-preparative HPLC purification and identified by MS. Thus, an integrated process of whole-cell-catalyzed conversion and product peak cutting partition collection provides a novel strategy for efficient biomanufacturing of high-purity C 3 G. [ABSTRACT FROM AUTHOR]

To maintain homeostasis in the face of intrinsic and extrinsic insults, cells have evolved elaborate quality control networks to resolve damage at multiple levels. Interorganellar communication is a key requirement for this maintenance, however the underlying mechanisms of this communication have remained an enigma. Here we integrate the outcome of transcriptomic, proteomic, and metabolomics analyses of genotypes including ceh1, a mutant with constitutively elevated levels of both the stress-specific plastidial retrograde signaling metabolite methyl -erythritol cyclodi phosphate (MEcPP) and the defense hormone salicylic acid (SA), as well as the high MEcPP but SA deficient genotype ceh1/ eds16, along with corresponding controls. Integration of multi-omic analyses enabled us to delineate the function of MEcPP from SA, and expose the compartmentalized role of this retrograde signaling metabolite in induction of distinct but interdependent signaling cascades instrumental in adaptive responses. Specifically, here we identify strata of MEcPP-sensitive stress-response cascades, among which we focus on selected pathways including organelle-specific regulation of jasmonate biosynthesis; simultaneous induction of synthesis and breakdown of SA; and MEcPP-mediated alteration of cellular redox status in particular glutathione redox balance. Collectively, these integrated multi-omic analyses provided a vehicle to gain an in-depth knowledge of genome-metabolism interactions, and to further probe the extent of these interactions and delineate their functional contributions. Through this approach we were able to pinpoint stress-mediated transcriptional and metabolic signatures and identify the downstream processes modulated by the independent or overlapping functions of MEcPP and SA in adaptive responses. [ABSTRACT FROM AUTHOR]

Developing circular economy is the only way to improve the efficiency of resource utilization. Whole-cell catalysis is an effective method to recycle enzymes, improve catalytic efficiency, and reduce production costs. The enzyme, α -L-rhamnosidase has considerable application prospects in the field of biocatalysis as it can hydrolyze a variety of α -L rhamnoses. In the present study, the genes for α -L-rhamnosidase (rhaB1) and enhanced fluorescent protein (EGFP) were co-expressed using a bi-promoter expression vector pRSFDuet1 and their enzymatic properties were evaluated. To our knowledge, this study has established an effective rhamnosidase-fluorescent indicator and whole-cell catalytic system for the first time. Moreover, we analyzed the change in the activity of the crude rhaB1-EGFP as well as its whole-cell during the biocatalysis process using fluorescence intensity. Recombinant rhaB1-EGFP as a product which contains rhaB1 and EGFP showed higher thermal stability, pH stability, and conversion efficiency than rhaB1, and its optimum temperature for rutin catalysis was ideal for industrial applications. Moreover, under the optimal conditions of a rutin concentration of 0.05 g/L, pH of 6.0, temperature of 40 °C, a yield of 92.5% was obtained. Furthermore, we demonstrated the relationship between the fluorescence intensity and enzyme activity. This study established a highly efficient whole-cell catalytic system whose activity can be evaluated by fluorescence intensity, providing a reference for enzyme recycling. Unlabelled Image • Two genes of rhaB1 and EGFP were firstly co-expressed by a bi-promoter expression vector. • Crude rhaB1-EGFP possessed higher thermal and pH stabilities than those of crude rhaB1. • Expression vector activity could be quantitatively detected by measuring fluorescence intensity. • Affinity of rhaB1-EGFP to substrate was not significantly reduced confirmed by SPR assay. • A labeled and recycling whole-cell catalyst was developed for flavonoids transformation. [ABSTRACT FROM AUTHOR]