Spice use in food: Properties and benefits

Spices are parts of plants that due to their properties are used as colorants, preservatives, or medicine. The uses of spices have been known since long time, and the interest in the potential of spices is remarkable due to the chemical compounds contained in spices, such as phenylpropanoids, terpenes, flavonoids, and anthocyanins. Spices, such as cumin (cuminaldehyde), clove (eugenol), and cinnamon (cinnamaldehyde) among others, are known and studied for their antimicrobial and antioxidant properties due to their main chemical compounds. These spices have the potential to be used as preservatives in many foods namely in processed meat to replace chemical preservatives. Main chemical compounds in spices also confer other properties providing a variety of applications to spices, such as insecticidal, medicines, colorants, and natural flavoring. Spices provide beneficial effects, such as antioxidant activity levels that are comparable to regular chemical antioxidants used so they can be used as a natural alternative to synthetic preservatives. In this review, the main characteristics of spices will be described as well as their chemical properties, different applications of these spices, and the advantages and disadvantages of their use.     

Prevalence of nocardiosis in an area of endemic tuberculosis

OBJECTIVE: To assess the quantity and nature of the proteins that adsorb to hydrocephalus shunt catheters after implantation, and to determine whether sufficient could accumulate to obstruct the catheter. DESIGN: Elution of proteins from 102 explanted shunt catheters, with protein assay and electrophoresis of the eluate, and scanning electron microscopy (SEM) of the catheters. RESULTS: The amount of protein elutable was extremely low, and significant protein, apart from a thin film, was not found on SEM. Qualitative analysis disclosed that most of the adsorbed protein was albumin. CONCLUSIONS: Protein deposition on hydrocephalus catheters does not occur in sufficient quantities to cause catheter obstruction.     

Oryctes monoceros Trapping with Synthetic Pheromone and Palm Material in Ivory Coast

Oryctes monoceros is the most serious pest in coconut plantations, causing up to 40% damage in tropical Africa, especially in Ivory Coast. With a view to reducing pest populations by olfactory trapping, field trials were carried out to assess the efficiency of a synthetic aggregation pheromone: ethyl 4-methyloctanoate (1), 4-methyloctanoic acid (2), a related volatile produced by males, and decaying palm material, either oil palm empty fruit bunches (EFB) or pieces of coconut wood (CW) of various ages. Vertical polyvinyl chloride tube traps (2 × 0.16 m with two openings in the upper half), embedded in the soil, were more efficient than 30-L pail traps 1.5 m above ground. EFB, which were inactive alone, synergized captures with synthetic pheromone. CW was more effective than EFB in comparative trials. Compound 2 did not catch any beetles when assessed with EFB, and reduced catches by 1 + EFB when tested at >10% with the pheromone. Trapping over 6 mo in 2002 and 2003 in a 19-ha coconut plot inside a 4,000-ha oil palm estate reduced damage from 3.8% in 2001 to 0.5% in 2002, then to 0.2% in 2003. Damage was 0.0% in 2004 with routine trapping using 32 traps, which caught 3369 beetles in 9 mo. The results are discussed in relation to other Dynastid palm pests and coconut protection in Ivory Coast.     

Ethyl propionate: Synergistic kairomone for african palm weevil,Rhynchophorus phoenicis L. (Coleoptera: Curculionidae)

Small trunk pieces of a freshly felled 10-year-old oil palm,Elaeis quineensis (Jacq.), were placed in a modified Nalgene desiccator, and volatiles captured for six days on Porapak Q. Gas chromatographic (GC) analysis of Porapak-Q-trapped volatiles with both flame ionization (FID) and electroantennographic detection (EAD) using male or femaleR. phoenicis antennae revealed several EAD-active compounds. They were identified as: ethyl acetate, ethyl propionate, isobutyl propionate, ethyl butyrate, and ethyl isobutyrate. In field experiments in the La Me Research Station, Côte d'Ivoire, ethyl propionate (50 mg/24 hr) but not all esters combined (50 mg/24 hr each) significantly increased capture ofR. phoenicis in pheromone-baited (3 mg/24 hr) traps. One kilogram of 1- to 3-day-old palm tissue was significantly more effective than ethyl propionate in enhancing pheromone attraction. Superior attraction of palm tissue may be attributed to additional as yet unknown semiochemicals. Alternatively, release rates and/or ratios of synthetic volatiles differed from those of palm tissue at peak attraction.     

Green Alternatives to Nitrates and Nitrites in Meat-based Products–A Review

Several food additives are added in food for their preservation to maintain the freshness of food (antioxidants) or to slow down or stop the growth of microorganisms (preservative agents). Nitrites and nitrates are used as preservative agents in meat. Nitrites give a smoked taste, a pinkish color in the meat and protect the consumers against the risk of bacterial deterioration. Their addition is however very limited as, in high dose, it can have risks on human health and the environment. Nitrites may also combine with secondary or tertiary amines to form N-nitroso derivatives. Certain N-nitroso compounds have been shown to produce cancers in a wide range of laboratory animals. Thus, alternatives of nitrates and nitrites are the object of numerous research studies. Alternatives, such as the addition of vitamins, fruits, chemicals products, natural products containing nitrite or spices, which have similar properties of nitrites, are in evaluation. In fact, spices are considered to have several organoleptic and anti-microbial properties which would be interesting to study. Several spices and combinations of spices are being progressively evaluated. This review discusses the sources of nitrites and nitrates, their use as additives in food products, their physicochemical properties, their negatives effects and the use of alternatives of nitrites and nitrates in preserving meat products.     

Glass Transition, Water, and Glycerol Effects on Sucrose Inversion in Pullulan-Sucrose Systems

ABSTRACT: Glass transition, water, and glycerol effects on sucrose inversion were investigated in pullulan-sucrose systems. Pullulan-sucrose (2:1), PS was dissolved into distilled water. Pullulan-sucrose-invertase, PSI, and pullulan-sucrose-invertase-glycerol, PSIG, were prepared by adding tiny amounts of invertase and glycerol, respectively, to similar PS blends. Samples were freeze-dried, further dehydrated over P₂O₅, and their physical properties were determined using water sorption isotherms and DSC. The amount of glucose formed by sucrose hydrolysis in samples stored at various RH was monitored. Water and glycerol plasticized the systems. DSC thermograms indicated complex phase behavior in PSI and PSIG depending on water content. Glycerol increased sucrose hydrolysis at 0.538 a_w, and favours it even at very moderate a_w.     

Glass transition and water effects on sucrose inversion in noncrystalline carbohydrate food systems

The effects of water and glass transition on the hydrolysis of sucrose by invertase in noncrystalline carbohydrate systems were investigated. Maltodextrin/sucrose (2:1) and maltodextrin/lactose/sucrose (1:1:1) were dissolved in distilled water. Invertase (10 mg/17.2 g) was added. Amorphous samples were produced by freeze-drying the solutions. Sorption isotherms were determined gravimetrically at 24 °C over the 0.113–0.763 a_w, and over 0.239–0.764 a_w, the glass transition, T_g was determined using differential scanning calorimetry (DSC). DSC and water sorption results suggested that samples remained noncrystalline. Sucrose inversion was analysed by monitoring glucose content during storage. Sucrose hydrolysis occurred at significant rates at 0.662 and 0.764 a_w. The rate increase was not related to the apparent glass transition of the systems.     

SARS-CoV-2 Infection Dysregulates Cilia and Basal Cell Homeostasis in the Respiratory Epithelium of Hamsters

Similar to many other respiratory viruses, SARS-CoV-2 targets the ciliated cells of the respiratory epithelium and compromises mucociliary clearance, thereby facilitating spread to the lungs and paving the way for secondary infections. A detailed understanding of mechanism involved in ciliary loss and subsequent regeneration is crucial to assess the possible long-term consequences of COVID-19. The aim of this study was to characterize the sequence of histological and ultrastructural changes observed in the ciliated epithelium during and after SARS-CoV-2 infection in the golden Syrian hamster model. We show that acute infection induces a severe, transient loss of cilia, which is, at least in part, caused by cilia internalization. Internalized cilia colocalize with membrane invaginations, facilitating virus entry into the cell. Infection also results in a progressive decline in cells expressing the regulator of ciliogenesis FOXJ1, which persists beyond virus clearance and the termination of inflammatory changes. Ciliary loss triggers the mobilization of p73⁺ and CK14⁺ basal cells, which ceases after regeneration of the cilia. Although ciliation is restored after two weeks despite the lack of FOXJ1, an increased frequency of cilia with ultrastructural alterations indicative of secondary ciliary dyskinesia is observed. In summary, the work provides new insights into SARS-CoV-2 pathogenesis and expands our understanding of virally induced damage to defense mechanisms in the conducting airways.     

Time-varying autoregressive spectral estimation for ultrasound attenuation in tissue characterization

In the field of biological tissue characterization, fundamental acoustic attenuation properties have been demonstrated to have diagnostic importance. Attenuation caused by scattering and absorption shifts the instantaneous spectrum to the lower frequencies. Due to the time-dependence of the spectrum, the attenuation phenomenon is a time-variant process. This downward shift may be evaluated either by the maximum energy frequency of the spectrum or by the center frequency. In order to improve, in strongly attenuating media, the results given by the short-time Fourier analysis and the short-time parametric analysis, we propose two approaches adapted to this time-variant process: an adaptive method and a time-varying method. Signals backscattered by an homogeneous medium of scatterers are modeled by a computer algorithm with attenuation values ranging from 1 to 5 dB/cm MHz and a 45 MHz transducer center frequency. Under these conditions, the preliminary results obtained with the proposed time-variant methods, compared with the classical short-time Fourier analysis and the short-time auto-regressive (AR) analysis, are superior in terms of standard deviation (SD) of the attenuation coefficient estimate. This study, based on nonstationary AR spectral estimation, promises encouraging perspectives for in vitro and in vivo applications both in weakly and highly attenuating media.