Bioactive Natural Products

Bioactive natural products have never ceased to play an important role in the search of novel therapeutic agents. Natural products from the nature such as the plant and marine sources form an integral part of the living system, and they have existed ever since the beginning of life. Therefore, it is undeniable that works related to natural products continue to develop in many aspects involving researchers from various scientific backgrounds. This special issue is dedicated to compile twelve articles on chemical and biological aspects of research developments in natural products

The Antioxidant Properties of Whey Permeate Treated Fresh-Cut Tomatoes

The aim of this research was to analyse the effects of three types of cheese whey permeate treatment on the antioxidant properties of fresh-cut tomatoes. Tomatoes were treated with whey permeate concentrate (PC), delactosed permeate (DP) and delactosed concentrate (DC), stored at 4 C for 10 days and compared to samples treated with the industry standard, chlorine (120 ppm). Samples treated with DP retained significantly higher antioxidant activity (FRAP) and total phenols (TP), when compared with those treated with PC and DC. DP showed significantly higher results than chlorine for DPPH, FRAP and TP. In DPPH assay, all whey permeate-treated samples showed similar antioxidant activity, while ascorbic acid and lycopene were unaffected by treatment. Among the three whey permeates, delactosed permeate showed the best results in maintaining the antioxidant properties of tomato, suggesting it could be used to enhance the antioxidant activity of fresh-cut tomato and retain the antioxidant components during storage

Valorisation of Apple Peels

The peels of processed apples can be recovered for further food applications. Limited information on the valorisation of this type of waste is available for cooking varieties, e.g. cv Bramley’s Seedling. Extracts from fresh or dried (oven-dried or freeze-dried) peels were obtained with solvents of different polarity (aqueous acetone or ethanol) and assayed for their total phenolic content and antioxidant capacity; their antiradical power was compared to herb extracts. The dried peels were also characterised as bulk powders by assessing their nutritional value and total phenolic content. High amounts of ascorbic acid (up to 4 mg/g, dry weight) and polyphenols (up to 27 mg gallic acid equivalents/g, dry weight) were found in the peels, with the latter contributing significantly to the antioxidant capacity; the nutrient profile was low in 2 protein (less than 10%, w/w) and total dietary fibre content (less than 40%, w/w). Higher yields of phenolic antioxidants were recovered with acetone from freeze-dried peels; the resulting extracts had equivalent antioxidant power to oregano leaves (Origanum vulgare L.). The combination of oven-drying/ethanol led to lower recovery yields of phenolic antioxidants; however, these conditions could increase the feasibility of the extraction process, leading to antioxidant extracts with lower energy or cost input, and higher suitability for further food use. The recovery of phenolic antioxidants from the peels of processed apples could be a valuable alternative to traditional disposal routes (including landfill), in particular for cooking varieties. The recycling process could enhance the growth of traditional culinary apple markets in UK and Ireland thanks to the new business opportunities for the peel-derived materials

Optimization of Application of Delactosed Whey Permeate Treatment to Extend the Shelf-Life of Fresh Cut Tomato Using Response Surface Methodology.

Optimization of delactosed whey permeate (DWP) treatment for fresh-cut tomato was accomplished by evaluating different quality, nutritional and microbial markers. Response surface methodology was applied to obtain polynomial model equations. DWP concentration (0 - 5 %) and storage (0 - 10 days) were used as independent factors in order to optimize the process. The analyses showed that increases in DWP concentration extended the quality of the fresh-cut tomato significantly (p3 % were scored unacceptable by the sensory panel due to perceived off-odours. DWP treatment also improved retention of ascorbic acid and lycopene over storage. The total aerobic counts and yeast and moulds were reduced by ~1.5 log cfu/ g and ~1.0 log cfu/ g respectively after 10 days of storage treated with 3 % DWP. Predicted models were highly significant (p2) ranging from 0.79 to 0.99. The study recommends the use of DWP at a concentration of 3 % to extend the shelf-life of fresh-cut tomato by preserving its quality and antioxidant properties during storage

Effect of Delactosed Whey Permeat Treatment on Physiochemical, Sensorial, Nutritional and Microbial Properties of Whole Tomatoes During Postharvest Storage.

The objective of this study was to investigate the efficacy of delactosed whey permeate (DWP) treatment on the physico-chemical, microbial and antioxidant compounds of tomatoes stored at 15 °C for 21 days compared with traditional chlorine treatment. Fresh tomatoes were treated with 3 ml/100ml DWP or 120 mg/L chlorine solutions and packed in perforated polypropylene bags. The results showed that DWP treatment significantly reduced the number of total aerobic counts (~1.62 log cfu/g) and yeast and moulds (~1.66 log cfu/g) of tomatoes compared to chlorine during storage. Moreover, the tomatoes treated by DWP remained firmer (22 %) than the control fruits and maintained significantly (

Extending the Shelf-Life of Tomato Using By-Product from Cheese Indistry.

The effects of three whey permeates were investigated as potential natural washing treatment for fresh-cut tomato and compared with chlorine (120 ppm). Whey permeate treated samples resulted in equivalent or better than chlorine for all these attributes. Whey permeates were equally effective as chlorine to control the micro-organisms of fresh-cut tomato during storage. The microbial counts at day 10 were significantly reduced (~1.0 log CFU/g) in all the treated samples compared to the control (water treated) samples. Moreover whey permeate treated fresh-cut tomatoes showed lower water activity (2 %) and POD activities (21%) than chlorinated samples after 10 days of storage. Whey permeate also inhibited the loss of firmness of treated tomato slices. Sensory scores for aroma were significantly higher in whey permeate treated samples than chlorine treated samples. Among the three types of whey permeate, delactosed permeate (DP) showed the best results in maintaining the quality of fresh-cut tomato. Practical ApplicationS The market sales of ready-to-eat fresh vegetables have grown rapidly in recent decades as a result of changes in consumer attitudes. The marketing of fresh-cut vegetables is limited by their short shelf-life due to the quick decline in post-processing quality. Many attempts have been made to increase the shelf life of fresh-cut fruit and vegetables and many attempts have been made to increase the use of whey permeate, a valuable by-product of cheese processing industry. This paper takes an interesting approach by attempting to use whey permeate as a preserving agent of fresh-cut tomato quality during storage

Optimisation of Accelerated Solvent Extraction of Antioxidant Compounds from Rosemary (Rosmarinus officinalis L.), Marjoram (Origanum majorana L.) and Oregano (Origanum vulgare L.) Using Response Surface Methodology

The present study optimised the accelerated solvent extraction (ASE) conditions (Dionex ASE® 200, USA) to maximise the antioxidant capacity of the extracts from three spices of Lamiaceae family; rosemary, oregano and marjoram. Optimised conditions with regard to extraction temperature (66–129 °C) and solvent concentration (32–88% methanol) were identified using response surface methodology (RSM). For all three spices results showed that 129 °C was the optimum temperature in order to obtain extracts with high antioxidant activity. Optimal methanol concentrations with respect to the antioxidant activity of rosemary and marjoram extracts were 56% and 57% respectively. Oregano showed a different response to the effect of methanol concentration and was optimally extracted at 33%. The antioxidant activity yields of the optimal ASE extracts were significantly (p \u3c 0.05) higher than solid/liquid extracts. The predicted models were highly significant (p \u3c 0.05) for both total phenol (TP) and ferric reducing antioxidant property (FRAP) values in all the spices with high regression coefficients (R2) ranging from 0.952 to 0.999

The Impact of Delactosed Whey Permeat Treatment on Shelf-life and Antioxidant Contents of Strawberries

The aim of this study was to investigate the effect of delactosed whey permeate (DWP) 27 treatment on antioxidant and physico-chemical properties of strawberries. Fresh strawberries 28 treated with 3 % DWP were analyzed for different quality, nutritional and microbiological 29 markers during 10 days of storage at 5 °C. The results showed that DWP treatment 30 significantly reduced incidences of decay (70 %) and numbers of total aerobic counts (~1.4 31 Log10 CFU/g) and yeast and moulds (~1.8 Log10 CFU/g). DWP treatment also inhibited the 32 loss of firmness (15 %) and maintained significantly (

Quality Markers of Functional Tomato Juice With Added Apple Phenolic Antioxidants

The natural approach to food stabilisation is at the forefront of research on plant compounds for food use. Matrix interactions and stability studies of the incorporated foods are necessary prior to further food processing. In this study, apple peel phenolic fractionated based on acidity (flavonoids and phenolic acids) were added to a commercial bottled tomato juice. The juice was left open i.e. air in the headspace at 4°C for 4 days to assess its physical-chemical quality, and for 10 days for the microbiological analysis. Quality markers were analysed (colour and turbidity) and showed that apple peel phenolics, particularly procyanidins, could form insoluble complexes with colloidal pectins thus affecting the turbidity; this led to brighter juice colours with enhanced yellowness due to added flavonol glycosides. The presence of other natural antioxidants (i.e. ascorbic acid and carotenoids) in the tomato juice was not affected by the presence of peel phenolics. Ascorbic acid was partially reduced during storage in all the juice samples. However, such decrease was counterbalanced by the presence of the added peel phenolics whose amount remained constant over time, thus contributing to a higher radical scavenging capacity compared to the control. The microbiological spoilage of the opened tomato juice was also delayed by 2-3 days in the presence of apple peel phenolics compared to the control. As a result, the open-package shelf-life of the bottled tomato juice was extended. The antimicrobial capacity was possibly due to the acidity of phenolic acids and the presence of apple flavonoids such as flavan-3-ols and flavonols that are likely to affect the transportation of nutrients across the cell membranes of the spoilage microflora

Characterization of Phenolics Composition in Lamiaceae Spices by LC-ESI-MS/MS

A total of 38 phenolic compounds in the solid/liquid extracts of five Lamiaceae spices such as rosemary, oregano, sage, basil and thyme were identified in the present study using LC-ESI-MS/MS. These compounds were distributed in four major categories namely hydroxycinnamic acid derivatives, hydroxybenzoic acid derivatives, flavonoids and phenolic terpenes. Among them, the category of flavonoids was the largest with 17 compounds. Identification of the phenolic compounds was carried out by comparing retention times and mass spectra with those of authentic standards. In case of unavailability of standards, phenolic compounds were identified based on accurate mass of pseudomolecular [M-H]- ions and tandem mass spectrometry (MS/MS) data. The results of accurate mass measurements fitted well with the elemental composition of the compounds. The diagnostic fragmentation patterns of the compounds during collision induced dissociation (CID) elucidated structural information of the compounds analysed