Although food waste is a valuable carbon source for biological nutrient removal systems with low organic wastewater because of high C/N and C/P ratios, it must be pretreated to promote the hydrolysis of particulates, which is considered as a rate-limiting step. This study investigated the effects of enzymatic pretreatment on hydrolytic solubilization of food waste with commercial enzyme. Both acidification efficiency and volatile fatty acid (VFA) production potential of enzymatically pretreated food waste were examined under controlled laboratory conditions. Experimental results indicated that protease exhibited the highest VSS reduction rate among three types of enzymes: carbohydrase, protease and lipase. A mixed enzyme treatment showed better reduction efficiency than a single enzyme treatment, and the highest volatile suspended solids (VSS) reduction was observed at an enzyme mixture ratio of 1:2:1 with carbohydrase:protease:lipase, respectively. It has been noted that pretreatment resulted in both maximum VFA production and the highest VFA content of soluble chemical oxygen demand at an enzyme mixture dosage of 0.1% (v/v). VFA production at this dosage revealed a 3.3 times higher rate than that of no-enzyme added fermenter. The dominant VFAs were n-butyrate followed by acetate. 

Bifunctional chelators have been successfully used to construct (64)Cu-labeled radiopharmaceuticals. Previously reported chelators with cross-bridged cyclam backbones have various essential features such as high stability of the copper(II) complex, high efficiency of radiolabeling at room temperature, and good biological inertness of the radiolabeled complex, along with rapid body clearance. Here, we report a new generation propylene-cross-bridged chelator with hybrid acetate/phosphonate pendant groups (PCB-TE1A1P) developed with the aim of combining these key properties in a single chelator. The PCB-TE1A1P was synthesized from cyclam with good overall yield. The Cu(II) complex of our chelator showed good robustness in kinetic stability evaluation experiments, such as acidic decomplexation and cyclic voltammetry studies. The Cu(II) complex of PCB-TE1A1P remained intact under highly acidic conditions (12 M HCl, 90 °C) for 8 d and showed quasi-reversible reduction/oxidation peaks at -0.77 V in electrochemical studies. PCB-TE1A1P was successfully radiolabeled with (64)Cu ions in an acetate buffer at 60 °C within 60 min. The electrophoresis study revealed that the (64)Cu-PCB-TE1A1P complex has net negative charge in aqueous solution. The biodistribution and in vivo stability study profiles of (64)Cu-PCB-TE1A1P indicated that the radioactive complex was stable under physiological conditions and cleared rapidly from the body. A whole body positron emission tomography (PET) imaging study further confirmed high in vivo stability and fast clearance of the complex in mouse models. In conclusion, PCB-TE1A1P has good potential as a bifunctional chelator for (64)Cu-based radiopharmaceuticals, especially those involving peptides.

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We report the production of taxadiene by transformation of N. benthamiana with a taxadiene synthase gene. The production was significantly increased by an elicitor treatment or metabolic pathway shunting. Paclitaxel (Taxol(®)) was first isolated from the bark of the pacific yew tree as an anticancer agent and has been used extensively to treat various types of cancer. Taxadiene, the first committed product of paclitaxel synthesis is cyclized from geranylgeranyl diphosphate (GGPP), and further complex hydroxylation and acylation processes of the unique taxane core skeleton produce paclitaxel. To accomplish de novo production of taxadiene, we transformed Nicotiana benthamiana with a taxadiene synthase (TS) gene. The introduced TS gene under the transcriptional control of the CaMV 35S promoter was constitutively expressed in N. benthamiana, and the de novo production of taxadiene was confirmed by mass spectroscopy profiling. Transformed N. benthamiana homozygous lines produced 11-27 μg taxadiene/g of dry weight. The highest taxadiene production line TSS-8 was further treated with an elicitor, methyl jasmonate, and metabolic pathway shunting by suppression of the phytoene synthase gene expression which resulted in accumulation of increased taxadiene accumulation by 1.4- or 1.9-fold, respectively. In summary, we report that the production of taxadiene in N. benthamiana was possible by the ectopic expression of the TS gene, and higher accumulation of taxadiene could be achieved by elicitor treatment or metabolic pathway shunting of the terpenoid pathway.

The seaweed Enteromorpha linza has long been used as a food source rich in natural bioactive compounds in various regions of the world. In the present study, the essential oil from E. linza, extracted by microwave-assisted hydrodistillation, was analyzed for its chemical composition and was evaluated for its free radicalscavenging and antioxidant potential. Gas chromatography and mass spectroscopy revealed the presence of 24 compounds in the seaweed essential oil (SEO), among which hexadecanoic acid (47.32%), nonadecadiene (18.19%) and azetidine (2.84%) are of medicinal importance. SEO exhibited strong hydroxyl radicalscavenging and superoxide scavenging activity of 91.37 and 53.50%, respectively, at 500 μg/mL. SEO also exhibited strong reducing power (0.90) and inhibited lipid peroxidation by 70.53% at 500 μg/mL. Based on the high antioxidant activities of compounds in SEO, it can be used as a food additive, preservative and dietary supplement to control the deleterious effects of oxidative stress with increased nutritional values. PRACTICAL APPLICATIONSExtensive investigations of free radicals and reactive oxygen species have revealed that these components have adverse effect on biomolecules that cause damage to macromolecules, including proteins, nucleic acids, lipids and carbohydrates, as well as various food products. Seaweeds are a favorable food source that serves as an effective resource for essential oil, which could be an alternative source of natural antioxidants, used as food additives or in food preservation. In this study, SEO from E. linza extracted by microwave-assisted hydrodistillation exhibited significantly high antioxidant and radical-scavenging potential, as well as inhibition of lipid peroxidation. These findings confirm that SEO from E. linza can be used by food industries as an additive, preservative or dietary supplement and as a nutraceutical to control the harmful effects of oxidative stress on food.

The solvent effects on the solvolysis of threo-2-aryl-1-methylpropyl p-toluenesulfonates were analyzed with the aid of the extended Winstein–Grunwald Equation. The aryl-assisted kΔ solvolysis of 2-(p-methoxyphenyl)-1-methylpropyl and 2-methyl-2-phenylpropyl p-toluenesulfonates failed to give a single linear correlation with the YOTs parameter. The dispersion against YOTs cannot be due to nucleophilic solvent assistance. The m values from the plots of 2-(p-methoxyphenyl)-1-methylpropyl and 2-methyl-2-phenylpropyl p-toluenesulfonates against YOTs were significantly lower than m = 1.0 for the limiting kc solvolysis. Significantly improved correlations (R > 0.99; SD < 0.14) were obtained for the p-methoxy, 3-chloro-4-methoxy, and p-methyl derivatives with the YΔ scale based on the solvolysis of 2-(p-methoxyphenyl)-2-methylpropyl p-toluenesulfonate, instead of with YOTs. No improvement by the YΔ treatment was obtained for the unsubstituted compound (R = 0.97; SD = 0.22). A new similarity comparison analysis in terms of YOTs and YΔ, i.e., log (k/k80E) = mcYOTs + mΔYΔ, was applied successfully to the present kΔ solvolyses. The degree of YΔ character relative to the YOTs one, scaled by mΔ/(mc + mΔ), varies for 1-methyl-2-phenylpropyl tosylates in the range from 1.0 to 0.00 in the consistent manner expected if the dispersion in the YOTs plot becomes less pronounced for solvolyses of less significant anchimeric assistance. There is a continuous spectrum of behavior between the extreme pure kc mechanism and the extreme pure kΔ one.

N-mono/dimethylated TE2A tetraazamacrocycles (MM-TE2A and DM-TE2A) were synthesized in high yields. Both Cu-MM/DM-TE2A complexes showed increased kinetic stability compared to that of Cu-TE2A, whereas Cu-DM-TE2A showed even higher in vitro stability than that of Cu-ECB-TE2A. MM-TE2A and DM-TE2A were quantitatively radiolabeled with 64 Cu ions and showed rapid clearance from the body to emerge as a potential efficient bifunctional chelator. KEYWORDS: Bifunctional chelator, copper complex, imaging agent, radiopharmaceutical A dvances in metal-based radiopharmaceuticals are driving research and development for medical diagnosis and therapy. 1−3 Several copper radioisotopes ( 60 Cu, 61 Cu, 62 Cu, 64 Cu, and 67 Cu) have attractive physical properties for medical applications, and various radioactive copper labeled bioconjugates are in the clinical trial pipeline. 4−6 The successful development of Cu(II)-based radiopharmaceuticals is not only dependent on targeting biomolecules but also highly dependent on the proper choice of a bifunctional chelator (BFC) coordinating radioactive Cu(II) ions. 7−9 Enormous efforts to construct an ideal BFC have been seen in recent decades. These BFCs should be radiolabeled with radioactive copper ions at a mild temperature with fast reaction kinetics, form stable complex with Cu(II), and possess rapid body clearance.Various tetraazamacrocyclic BFCs containing N-acetic acid pendant arms have been utilized for Cu(II) complexation (Figure 1). The kinetic stability of BFC-Cu(II) complexes could indicate their in vivo stability more closely than thermodynamic stability. 10 The order of stability for the BFC-Cu(II) complexes is Cu-ECB-TE2A ≫ Cu-TETA ≈ Cu-DOTA > Cu-EDTA. 10,11 It is now well accepted that 64 Cu-TETA and 64 Cu-DOTA are prone to transchelation of 64 Cu ions to proteins under physiological conditions resulting in slow body clearance of radioactivity. 12,13 Ethylene cross-bridged (ECB)-TE2A shows excellent kinetic stability for Cu(II) ions in acid decomplexation experiments and equally good in vivo inertness. However, despite this high stability, ECB-TE2A suffers from shortcomings such as cumbersome synthesis (total synthesis time: 35 days and 45% overall yield from cyclam), and harsh radiolabeling conditions for 64 Cu ions (1−2 h at 75−95°C). 14, 15 We have reported that TE2A (1,8-N,N′-bis-(carboxymethyl)-1,4,8,11-tetraazacyclotetradecane) is a better chelator for Cu(II) ions than TETA (1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetraacetic acid) and DOTA (1,4,7,10-tetraazacyclodo-

A method for the regioselective synthesis of a wide range of dihydrothiophenes was developed from the rhodium-catalyzed transannulation of 1,2,3-thiadiazoles with aliphatic, aromatic, and heteroaromatic alkenes. Tandem rhodium-catalyzed transannulation of 1,2,3-thiadiazoles with alkenes followed by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) oxidation was also demonstrated for the one-pot regioselective synthesis of various thiophenes. Advantages of the present method include a broad substrate scope, wide functional group compatibility, and high regioselectivity.