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Rise in human population and gradual decline in fossil fuels are increasing the demand for fuels and causing an upsurge in fuel prices and global warming. Concomitantly, consumers have raised their health awareness by taking various supplements, e.g. omega-3 fatty acids, thus calling for advanced nutraceuticals. Both issues are addressed by recent research on microalgae, which can be easily cultivated to produce lipidic biofuels and active drugs. Here, we reviewed the types and biosynthesis of microalgal lipids. We discuss genetic engineering and manipulation of cultivation conditions for enhancing lipid production. We present techniques for lipid extraction, with focus on green techniques. We also discuss the technical and economic challenges in manufacturing microalgae-based biofuels and other bioproducts at the industrial scale. Last, the market potentials and further research directions for future commercialization of microalgae lipids are discussed.

The capacity to diagnose cancer with the existing endogenous biomarkers remains limited because biomarkers usually act at the tumor site and are thus challenging to be detected directly from body fluids with high sensitivity and specificity, especially in the early stage of tumorigenesis. Here, we demonstrate an exogenous tumor-penetrating nanomarker composed of fluorescent nanoparticles conjugated with specific fluorescein-labeled peptides. The injectable nanomarkers perform four functions: they penetrate the tumor, target sites of cancer, cleave specific peptides by on-target protease, and drop off the labeled peptide into host urine for fluorescent detection. Sensitive in vivo tracking and monitoring of the cyclic process of the nanomarker was also accomplished. The nanomarker can noninvasively diagnose and monitor tumors with a volume of about 17 mm3 without invasive core biopsies. Enhanced capacity of early point-of-care detection for cancer is accomplished by receptor-dependent specificity of the signal generation in the urine compared with clinically used blood biomarkers.

The Hemipteran predator, Cyrtorhinus lividipennis, feeds on the eggs and nymphs of rice planthoppers and leafhoppers. We previously demonstrated that sublethal concentrations of imidacloprid stimulated the reproduction of C. lividipennis. Considering the essential roles of juvenile hormone (JH) in insect reproduction, we speculated that sublethal concentrations of imidacloprid may stimulate the reproduction of C. lividipennis by regulating JH level. To test this, we cloned C. lividipennis JH acid methyl transferase (ClJHAMT) and JH esterase (ClJHE), which are responsible for JH biosynthesis and degradation genes, respectively. We then knocked down ClJHAMT by injecting dsRNA into C. lividipennis nymphs and found that emerging female adults exhibited 88.8% lower expression of the vitellogenin gene (ClVg) and the number of eggs was reduced by 41.5% as compared with controls. Silencing ClJHE increased ClVg mRNA expression by 275.0% but did not affect fecundity. A sublethal concentration of imidacloprid (LC20) increased the JH titer in females by 35.3% and 60.6% at 24 and 48 h post-emergence, respectively. In treatments containing both imidacloprid and dsJHAMT, the silencing of CLJHAMT reduced the number of eggs produced by adult females by 21.4% as compared to the control (imidacloprid + dsGFP). Our results indicated that sublethal concentration of imidacloprid may induce C. lividipennis reproduction by upregulating JH level via JHAMT. The finding could provide valuable information for improved integration of C. lividipennis and insecticides in pest management.

Bobbin tool friction stir welding (BT-FSW) is a variant of conventional friction stir welding (FSW). It can be used to weld complex curvature structures and closed sections by adding an extra shoulder instead of a rigid backing anvil, which expands the potential application of FSW in aerospace, railway, automotive and marine industries. BT-FSW has some significant advantages over conventional FSW such as no root flaws, full weld penetration, low stiffness requirements for machines and fixtures, balanced heat input, lower distortion and thus has broad prospects for development. At present, there have been numerous research reports on BT-FSW, but its widespread use is still restricted due to various factors such as tool life, process stability, control complexity and implementation cost. In this paper, the domestic and foreign research progress of BT-FSW is reviewed from four aspects of bobbin tool design and classification, temperature field and flow field during welding, microstructure and mechanical properties of welded joints as well as industrial application, and then the possible research hotspots of BT-FSW in the future are pointed out. This paper mainly aims to help researchers have a comprehensive and in-depth understanding of BT-FSW.

Various studies showed that the suppression of α-glucosidase activity can impede the glucose absorption in our body, and therefore, it can be used to treat type 2 diabetes. Hence, the compounds with anti-α-glucosidase have gained considerable attention because of their potential application in diabetes treatment. In previous literature studies, these anti-α-glucosidase compounds were extracted from plants and fungus. Less studies are being conducted to identify the anti-α-glucosidase compounds in the microbial community. In this study, 23 marine bacterial strains were screened for their potential to suppress the α-glucosidase activity. The highest inhibitory activity was exhibited by isolated L06 which was identified as Oceanimonas smirnovii EBL6. The cultivation conditions, such as temperature and pH, were optimized to increase the production of α-glucosidase inhibitors by Oceanimonas smirnovii EBL6 strain. The result findings showed that the highest yield of α-glucosidase inhibitors can be obtained at the culture time of 120 h, fermentation temperature of 30 °C, and pH 4.6. Under these conditions, the inhibitory activity of α-glucosidase can reach 81%. The IC50 of n-butanol extract was 13.89 μg/ml, while standard acarbose was 31.16 μg/ml. Overall, these findings suggest that Oceanimonas smirnovii produces α-glucosidase inhibitors and could been applied in the biochemical and medicinal fields in the future.

Waste cooking oil (WCO) is considered as one of the hazardous wastes because improper disposal of WCO can cause significant environmental problems such as blockages of drains and sewers as well as water or soil pollution. In this review, the physical and chemical properties of WCO are evaluated along with its regulations and policies in different countries to promote WCO refined biofuels. Blended WCO can be an auxiliary fuel for municipal solid waste incinerators while the heat produced is able to form superheated steam and subsequently generate electricity via combined heat and power system. Also, WCO contains high ratio of hydrogen atoms compared to carbon and oxygen atoms, making it able to be catalytically cracked, synthesizing hydrogen gas. WCO-based biodiesel has been traditionally produced by transesterification in order to substitute petroleum-based diesel which has non-degradability as well as non-renewable features. Hence, the potentials of hazardous WCO as a green alternative energy source for electricity generation, hydrogen gas as well as biofuels production (e.g. biodiesel, biogas, biojet fuel) are critically discussed due to its attractive psychochemical properties as well as its economic feasibility. Challenges of the WCO utilization as a source of energy are also reported while highlighting its future prospects.

Global plastic pollution has been a serious problem since many years and micro (nano) plastics (MNPs) have gained attention from researchers around the world. This is because MNPs able to exhibit toxicology and interact with potentially toxic elements (PTEs) in the environment, causing soil toxicity. The influences of MNPs on the soil systems and plant crops have been overlooked despite that MNPs can accumulate in the plant root system and generate detrimental impacts to the terrestrial environments. The consumption of these MNPs-contaminated plants or fruits by humans and animals will eventually lead to health deterioration. The identification and measurement of MNPs in various soil samples is challenging, making the understanding of the fate, environmental and ecological of MNPs in terrestrial ecosystem is limited. Prior to sample assessment, it is necessary to isolate the plastic particles from the environment samples, concentrate the plastic particles for analysis purpose to meet detection limit for analytical instrument. The isolation and pre-concentrated steps are challenging and may cause sample loss. Herein, this article reviews MNPs, including their fate in the environment and toxic effects exhibited towards soil microorganisms, plants and humans along with the interaction of MNPs with PTEs. In addition, various analysis methods of MNPs and management of MNPs as well as the crucial challenges and future research studies in combating MNPs in soil system are also discussed.

Oil pollution which results from industrial activities, especially oil and gas industry, has become a serious issue. Cinder beats (CB), coconut fiber (CF) and polyurethane foam (PUF) are promising immobilization carriers for crude oil biodegradation because they are inexpensive, nontoxic, and non-polluting. The present investigation was aimed to evaluate this advanced technology and compare the efficiency of these immobilization carriers on supporting purple phototrophic bacterial (PPB) strains in hydrocarbon biodegradation of crude oil contaminated seawater. The surface of these biocarriers was supplemented with crude oil polluted seawater and immobilized by PPB strains, Rhodopseudomonas sp. DD4, DQ41 and FO2. Through scanning electron microscopy (SEM), the bacterial cells were shown to colonize and attach strongly to these biocarriers. The bacteria-driven carrier systems degraded over 84.2% supplemented single polycyclic aromatic hydrocarbons (PAHs). The aliphatic and aromatic components in crude oil that treated with carrier-immobilized consortia were degraded remarkably after 14 day-incubation. Among the three biocarriers, removal of the crude oil by CF-bacteria system was the highest (nearly 100%), followed by PUF-bacteria (89.5%) and CB-bacteria (86.3%) with the initial crude oil concentration was 20 g/L. Efficiency of crude oil removal by CB-bacteria and PUF-bacteria were 86.3 and 89.5%, respectively. Till now, the studies on crude oil degradation by mixture species biofilms formed by PPB on different carriers are limited. The present study showed that the biocarriers of an oil-degrading consortium could be made up of waste materials that are cheap and eco-friendly as well as augment the biodegradation of oil-contaminated seawater.

An integrated aptamer macroarray functionalized with reduced graphene oxide (rGO) to specifically capture and sensitively detect cancer cells is reported. The capture for cancer cells is based on effective recognition of the modified rGO surface through the aptamer against epithelial cell adhesion molecule (EpCAM). The rough structure of rGO enhances morphologic interactions between rGO film interface and the cancer cells, while super-hydrophilicity of modified rGO hinders nonspecific cell capture. The synergistic interactions offer the aptamer macroarray high efficiency of cancer cell capture. By means of a turn-on fluorescence strategy based on the conformation change of the aptamer induced by the target recognition, the enriched cancer cells can be directly read out at excitation/emission wavelengths of 550/680 nm without washing, separation, and dying steps. The working range is 1 × 102 to 2 × 104 cells per mL with a detection limit of 22 cells per mL. The results indicate that the aptamer macroarray has a considerable foreground for early diagnosis, therapy, and monitoring of cancer.

Microalgae are autotroph organisms that utilise light energy to synthesize various high-value bioactive compounds such as polysaccharides, proteins and lipids. Due to its fast growth rate and capability to survive in harsh environment, microalgae nowadays are applied in various industrial areas. The process of obtaining microalgae-based biomolecules starts with the selection of suitable microalgae strain, cultivation, followed by downstream processing of the biomass (i.e., pre-treatment, harvesting, extraction and purification). The end products of the processes are biofuels and other valuable bioproducts. Nevertheless, low production yield and high-cost downstream processes are the emerging bottlenecks which need to be addressed in the upscaling of extracted compounds from microalgae biomass. To conclude, tremendous efforts are required to overcome these challenges to revolutionize microalgae into a novel and green factory of different bioactive compounds for industrial necessities to satisfy and fulfil global demands.

Sensitive detection, especially in situ monitoring of intracellular MMP-2, is extremely desirable for cancer early diagnosis, evaluation of therapy, and discovery of the new anti-cancer drug. Herein, a programmed microcapsule-type MMP-2 responsive nanosensor based on mesoporous silica nanoparticles (MSN) is developed to realize in situ imaging monitoring of intracellular MMP-2. In the wrapping anti-MMP-2 antibody sealed microcapsule-type nanosensor, a black hole fluorescence quencher (BHQ-3) is covalently combined onto the inner walls of the MSN mesopores, and the fluorescein Cy5 is loaded in the cavity of MSN, resulting in fluorescence “OFF” state. With the existence of MMP-2, the anti-MMP-2 antibody which acts as a “bio-lid” could detach from the surface of the nanosensor owing to the binding MMP-2 with the antibody, leading to the release of the fluorescein Cy5 to produce fluorescence “ON” state. The prepared programmed microcapsule-type MMP-2 responsive nanosensor is capable of sensitive in situ imaging monitoring of intracellular MMP-2 and is further verified by tracking the change of intracellular MMP-2 level in response to MMP-2-repressive drugs. Thus, the nanosensor give a platform for in vivo detection of biomarkers for diagnosis, evaluation of therapy, and discovery of the new anti-cancer drug.

A new rearranged lignan, asasiebolin (1), was isolated from a kind of traditional Chinese medicine Asarum sieboldii, together with two known lignans, L-sesamin and L-asarinin. Asasiebolin (1) contained a benzo[d][1,3]dioxole-5-carboxyl moiety linked to a hydroxymethyl at C-3 of the tetrahydrofuran core, which might be rearranged after a cleavage from C-4. The structure with relative configuration was elucidated by in-depth spectral methods.

Magnetically weakly coupled diamond chains in the 3D metal–organic framework are well separated by diamagnetic [V4O12]4− cluster units and semi-rigid ligands, and exhibit not only weak ferromagnetic interactions with frustrated spin canting but also single-chain magnets with slow magnetic relaxation below 3.4 K.

FOrster resonance energy transfer (FRET)-based biosensors have achieved great success for biological applications. However, what is not extensively appreciated is the growing role as versatile FRET biosensors within a similar biological context. This review provides a brief introduction of recent advances in principle, the designing strategies and kinds of applications of FRET biosensors. For each FRET biosensor, the appropriate background and fabrication is explained before studying their related applications. The prominent roles of nanomaterials are present in the development of more sensitive and specific FRET biosensors. Finally, the challenges and outlooks of FRET biosensors are emphasized.

Endotoxin, also known as lipopolysaccharide (LPS), can induce strong immune response that causes casualties annually. This number may be greatly reduced if specific, robust, sensitive and more capable of clearance LPS biosensor existed. By introducing a LPS specific binding peptide to a typical aggregation induced emission (AIE) fluorophore, 1-(4-carboxylbenzene)-1,2,2-triphenyl (CTPY), a robust, sensitive and specific “OFF-ON” fluorescent biosensor was developed. The biosensor can achieve LPS sensing of a linear relationship in the concentration range of 0.1–1 μM with a detection limit of 6.97 nM. Moreover, a rapid clearance of LPS is simultaneous realized by integration of mesoporous silica nanospheres with a LPS recognition peptide. Such robust biosensor with highly specific detection and rapid clearance based on LPS specific binding peptide hold considerable promise in diverse clinical and biological applications.

An immunoassay is described for either colorimetric and fluorometric determination of the cancer biomarker α-fetoprotein (AFP). It is making use of ZnS nanospheres modified with CdTe quantum dots (QDs). These display strong fluorescence due to the enrichment of the QDs onto the porous ZnS nanospheres. In this assay, the release of millions of zinc(II) ions can be triggered to form a purple complex (with an absorption maximum at 571 nm) on addition of the reagent 2-(5-nitro-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino) phenol. This results in a sensitive colorimetric immunoassay which can also be used as a visual test. It represents an enzyme-free alternative to the commonly used ELISAs. It also can be evaluated by fluorometry (with excitation/emission maxima at 400/645 nm). The detection limits are 10 pg·mL−1 for fluorometry and 7 pg·mL−1 for colorimetry. This sensitivity is better by one order of magnitude than that of the commercial ELISA. The dual detection feature provides good complementarity and reduces the risk of false-positive or false-negative results.