School of Agriculture, Food and Ecosystem Sciences - Research Publications
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ItemDioscorea Plants: A Genus Rich in Vital Nutra-pharmaceuticals-A Review(BRIEFLAND, 2019)Dioscorea species, known as "Yams," belong to family Dioscoreaceae. This genus consists of more than 600 species distributed from Africa, Asia, the Caribbean's South America, and the South Pacific islands. Their organoleptic properties make them the most widely used carbohydrate food and dietary supplements. The underground and/or aerial tubers represent valuable sources of proteins, fats, and vitamins for millions of people in West Africa. This review gives a shot of secondary metabolites of Dioscorea plants, including steroids, clerodane diterpenes, quinones, cyanidins, phenolics, diarylheptanoids, and nitrogen-containing compounds. This review collected the evidence on biological properties of description Dioscorea, including in-vitro and in-vivo studies. Dioscorea species contain promising bioactive molecules i.e. diosgenin that support their different biological properties, including antioxidant, hypoglycaemic, hypolipidemic, anti- antimicrobial, inflammatory, antiproliferative, androgenic, estrogenic, and contraceptive drugs. Indeed, besides its nutrient values, Dioscorea is a potential source of bioactive substances of interest in the prevention/treatment of several diseases, and thus represents a great challenge in developing countries. However, ethnomedicinal potential should be validated and further researches on pharmacological properties and phytochemical composition should be carried out. Particularly, doing some studies to convert the preclinical results to clinical efficacy should be guaranteed. Dioscorea, Food plant, Traditional use, Phytochemistry, Pharmacological activities.
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ItemNo Preview AvailableFarm to Consumer: Factors Affecting the Organoleptic Characteristics of Coffee. II: Postharvest Processing Factors(Wiley, 2018-09-01)The production and consumption of coffee are increasing despite the roadblocks to its agriculture and global trade. The unique, refreshing, and stimulating final cupping quality of coffee is the only reason for this rising production and consumption. Coffee quality is a multifaceted trait and is inevitably influenced by the way it is successively processed after harvesting. Reportedly, 60% of the quality attributes of coffee are governed by postharvest processing. The current review elaborates and establishes for the first time the relationship between different methods of postharvest processing of coffee and its varying organoleptic and sensory quality attributes. In view of the proven significance of each processing step, this review has been subdivided into three sections, secondary processing, primary processing, and postprocessing variables. Secondary processing addresses the immediate processing steps on the farm after harvest and storage before roasting. The primary processing section adheres specifically to roasting, grinding and brewing/extraction, topics which have been technically addressed more than any others in the literature and by industry. The postprocessing attribute section deals generally with interaction of the consumer with products of different visual appearance. Finally, there are still some bottlenecks which need to be addressed, not only to completely understand the relationship of varying postharvest processing methods with varying in-cup quality attributes, but also to devise the next generation of coffee processing technologies.
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ItemLC-ESI-QTOF/MS Profiling of Australian Mango Peel By-Product Polyphenols and Their Potential Antioxidant Activities(MDPI AG, 2019-10-18)Mango (Mangifera indica L.) is one of the most important fruits in the world. Mango peel is an important by-product that is rich in polyphenols and it could have high economic value if it is e_ectively utilized. Phenolic characterization is an essential step in the commercial utilization of mango peel by-products as food ingredients. Herein, qualitative and quantitative analyses of two Australian mango peel “Keitt” and “Kensington Pride” (K&P) by-products were conducted while using liquid chromatography coupled to electrospray ionisation and quadrupole time of flight mass spectrometry (LC-ESI-QTOF/MS) and high-performance liquid chromatography coupled to photodiode array detector (HPLC-PDA). A total of 98 polyphenols compounds were tentatively identified in both Keitt peel and K&P peel extracts, with greater concentrations of these compounds being detected in Keitt peel. The total phenolic content (TPC), total flavonoid content (TFC), and a total tannin content (TTC) were determined. The antioxidant activity of mango peel by-products was determined while using 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant assay, ferric reducing antioxidant power (FRAP) assay, and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assay. Keitt peel contained higher concentrations of total phenolic compounds, flavonoids, and tannins and had higher antioxidant capacity in DPPH, FRAP, and ABTS assays as compared to K&P peel. In HPLC-PDA quantification, the predominant phenolic compounds in Keitt peel and K&P peel were catechin (62.32 _ 0.01 mg/gd.w.) and syringic acid (17.78 _ 0.01 mg/gd.w).
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ItemMarine Processing Waste: In Search of Bioactive Molecules(Longdom Publishing, 2016)
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ItemSupplementation of Powdered Black Cumin (Nigella sativa) Seeds Reduces the Risk of Hypercholesterolemia(Functional Food Center, 2011)Background: Functional and nutraceutical foods are gaining immense popularity among the masses. Plants and their bioactive molecules are of prime importance. Although various plants from different geographical areas have been tested in the past, many horizons still need to be addressed. Black cumin (Nigella sativa L.) is one such example that is quite popular in South Asia and the Middle East. Context and purpose: The present research study was designed to expedite the role of black cumin seed in reducing the risk of hypercholesterolemia. For the purpose, thirty Sprague dawley rats were procured from the National Institute of Health (NIH) in Islamabad, Pakistan, and further split up into three groups, (10 rats each). Experimental diets were prepared using powdered black cumin (PBC) at 1% and 2%, and compared with the placebo. Results: The results revealed that PBC was effective in reducing the serum cholesterol, triglycerides, and low-density lipoproteins (LDL). Additionally, the experimental diets resulted in a non-significant increase in high-density lipoprotein (HDL). Overall, powdered black cumin at 1% and 2% reduced cholesterol level by 6.73, and 4.48%, LDL by 24.79, and 24.32% respectively. However, the supplementation of PBC at 2% resulted in marked variations as increasing tendency, which was recorded for cholesterol and triglycerides contents after 28 days of study. Conclusion: Present research investigation brightened the prospects of using powdered black cumin seed in diet based therapies to improve the lipid profile. Further studies are still required to assess the phytochemistry of the plants and indeed the functional ingredients responsible for such health benefits. Such studies would bring meticulousness for utilization of black cumin seeds as a functional food.
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ItemGrowth Performance and Characterization of Meat Quality of Broiler Chickens Supplemented with Betaine and Antioxidants under Cyclic Heat Stress(MDPI, 2019-09)Heat stress (HS) causes oxidative stress, which compromises broiler performance and meat quality. The aim of this study was to determine whether dietary antioxidants could be used as an amelioration strategy. Seventy-two day-old-male Ross-308 chicks were exposed to either thermoneutral or cyclical heat stress conditions. Diets were either control commercial diet (CON), CON plus betaine (BET), or with a combination of betaine, selenized yeast, and vitamin E (BET + AOX). Heat stress increased the rectal temperature (p < 0.001), respiration rate (p < 0.001), decreased blood pCO2 (p = 0.002), and increased blood pH (p = 0.02), which indicated the HS broilers had respiratory alkalosis. Final body weight was decreased by HS (p < 0.001), whereas it was improved with BET (p = 0.05). Heat stress reduced cooking loss (p = 0.007) and no effect on drip loss, while BET decreased the drip loss (p = 0.01). Heat stress reduced the myofibril fragmentation index (p < 0.001) and increased thiobarbituric acid reactive substances (p < 0.001), while these were improved with the combination of BET + AOX (p = 0.003). In conclusion, BET overall improved growth rates and product quality in this small university study, whereas some additional benefits were provided by AOX on product quality in both TN and HS broilers.
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ItemLC-ESI-QTOF/MS Characterisation of Phenolic Acids and Flavonoids in Polyphenol-Rich Fruits and Vegetables and Their Potential Antioxidant Activities(MDPI, 2019-09)Polyphenols are naturally occurring compounds found largely in fruits and vegetables. The antioxidant properties of these polyphenols including total phenolic content (TPC), total flavonoid content (TFC), tannin content, 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH), 2,2'-azinobis-(3-ethylbenzo-thiazoline-6-sulfonic acid) (ABTS) scavenging abilities and ferric ion reducing antioxidant power (FRAP) were measured among sixteen (16) plant foods (mango, blueberry, strawberry, black carrot, raspberry, dark grapes, garlic, ginger, onion, cherry, plum, apple, papaya, peach, pear and apricot) by modifying, standardising and translating existing antioxidant methods using a 96-well plate reader. Eighteen targeted phenolic acids and flavonoids were characterised and quantified using high-performance liquid chromatography-photometric diode array (HPLC-PDA) and verified by modifying an existing method of liquid chromatography coupled with electrospray-ionisation triple quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF/MS). While most of these compounds were accurately detected by the HPLC-PDA at a low concentration, a few polyphenols in low concentrations could be only be characterised using the LC-ESI-QTOF/MS method. Our results showed that mango possessed the highest overall antioxidant activity, phenolic acid and flavonoid content among the selected fruits. Factor analysis (FA) and Pearson's correlation tests showed high correlations among ABTS, DPPH, FRAP and phenolic acids, implying the comparable capabilities of scavenging the DPPH/ABTS free radicals and reducing ferric ions from the antioxidant compounds in the samples. Phenolic acids contributed significantly to the antioxidant activities, and flavonoids contributed more to tannin content based on the correlations. Overall, methods modified and standardized in this study can provide better understanding of high throughput technologies and increase the reliability of antioxidant data of different plant foods.
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ItemLC-ESI-QTOF/MS Characterization of Phenolic Compounds in Palm Fruits (Jelly and Fishtail Palm) and Their Potential Antioxidant Activities(MDPI AG, 2019-12-20)Hops (Humulus lupulus L.) and juniper berries (Juniperus communis L.) are two important medicinal plants widely used in the food, beverage, and pharmaceutical industries due to their strong antioxidant capacity, which is attributed to the presence of polyphenols. The present study is conducted to comprehensively characterize polyphenols from hops and juniper berries using liquid chromatography coupled with electrospray-ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF/MS) to assess their antioxidant capacity. For polyphenol estimation, total phenolic content, flavonoids and tannins were measured, while for antioxidant capacity, three different antioxidant assays including the 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant assay, the 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical cation decolorization assay and the ferric reducing-antioxidant power (FRAP) assay were used. Hops presented the higher phenolic content (23.11 ± 0.03 mg/g dw) which corresponded to its strong antioxidant activity as compared to the juniper berries. Using LC-ESI-QTOF/MS, a total of 148 phenolic compounds were tentatively identified in juniper and hops, among which phenolic acids (including hydroxybenzoic acids, hydroxycinnamic acids and hydroxyphenylpropanoic acids) and flavonoids (mainly anthocyanins, flavones, flavonols, and isoflavonoids) were the main polyphenols, which may contribute to their antioxidant capacity. Furthermore, the HPLC quantitative analysis showed that both samples had a high concentration of phenolic acids and flavonoids. In the HPLC quantification, the predominant phenolic acids in hops and juniper berries were chlorogenic acid (16.48 ± 0.03 mg/g dw) and protocatechuic acid (11.46 ± 0.03 mg/g dw), respectively. The obtained results highlight the importance of hops and juniper berries as a rich source of functional ingredients in different food, beverage, and pharmaceutical industries.
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ItemCashew nut allergy; immune health challenge(Elsevier, 2019-04)Background Cashew nut allergy is a significant tree nut allergy that is increasing gradually and becoming serious health issue these days. Allergens responsible for cashew nut allergy are highly potent and for some people, these reactions have the potential to be severe and even life-threatening (anaphylaxis). Increased consumption of cashew nuts and a change in eating and cooking may be responsible. It's time to spread the knowledge and awareness about cashew nut allergy among society, clinics and development of clinical confession. Scope and approach In recent era, various researches regarding cashew nut allergy are under consideration. In this comprehensive review, investigations were carried to identify aspects of cashew nut allergy including its prevalence, characteristics, processing effects, different allergens, diagnosis and management. Key findings and conclusion Main etiology is the utilization of minor quantity of cashew nut allergens like Ana-o-3, Ana-o-1 and Ana-o-2, proposed to be very powerful as compared to other tree nuts. Its prevalence is increasing especially in children. Several methods like oral immunotherapy, adrenaline auto-injector device and enzymatic processing are very helpful in the treatment of this emerging type of allergy. Moreover, labelling of foods products having cashew nuts plays significant role in prevention of cashew nut allergy. This information concludes that allergen of cashew nut allergy may be powerful that is chronic cause of many immune disorders.
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ItemNo Preview AvailableToxicological and safety evaluation of Nigella sativa lipid and volatile fractions in streptozotocin induced diabetes mellitus(Elsevier, 2014-09)Objective: To evaluate the toxicological aspects of Nigella sativa (N. sativa) lipid and volatile fractions in streptozotocin induced diabetes mellitus. Methods: National Institute of Health (NIH), Islamabad provided us thirty Sprague Dawley rats that were further divided into three groups, i.e. control, N. sativa lipid fraction (4%) and N. sativa volatile fraction (0.3%), respectively. The serological and haematological indices were evaluated at 4-week intervals during 56 d study. Results: The results indicated that the diabetes mellitus imparted negative effects on various serological and haematological attributes. However, supplementation of the N. sativa lipid fraction and N. sativa volatile fraction ameliorated the adverse consequences of diabetes mellitus. The diabetes induced renal toxicity and imbalanced serum chemistry were slightly modulated by experimental diets. However, the impact of essential oil was more significant as compared to the fixed oil. Conclusions: In a nutshell, experimental diets containing N. sativa lipid fraction and N. sativa volatile fraction are effective without having any toxicological effects, and experimental diets reduced toxicological and adverse consequences of diabetes mellitus.