Moaz Alzahrani - Academia.edu (original) (raw)
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Papers by Moaz Alzahrani
Plant antimicrobials fulfil the needs of today’s consumer looking for wholesome food without chem... more Plant antimicrobials fulfil the needs of today’s consumer looking for wholesome food without chemical preservatives.
These can be classified as novel compounds obtained from plants that delay microbial growth of pathogens and spoilage
organisms in food. The antimicrobial activity of plant extracts that is observed in in-vitro conditions is quite different to its
effect in complex food systems. In most cases antimicrobial activity is decreased due to interactions with food
components. This could be a challenge in utilizing plant antimicrobials, as a higher concentration could result in
unfavourable changes to the taste and aroma of food. There is growing scientific evidence of the potential use of plant
antimicrobials for the extension of shelf life in food. This review covers recent trends in using plant antimicrobials in food,
their combination with other technologies, their role in controlling food pathogens and mechanisms of action.
The antimicrobial activity of essential oils and their components has been recognized for a very ... more The antimicrobial activity of essential oils and their components has been recognized for a very long time. Essential oils
(EOs) are made from a very complex mixture of volatile molecules that are produced by the secondary metabolism of
aromatic and medicinal plants and can be obtained by distillation of different parts of plants. The large number of studies on the antimicrobial activity of EOs has allowed the scientific recognition of these compounds on the control of a wide range of microbial pathogens. The progresses made on the investigation of the mode of action of EOs against bacterial cell targets give us new perspectives to combat persistent and antimicrobial resistant bacterial pathogens. The recent
investigation on the activity of EOs disruption of quorum sensing process is an excellent example. On the other hand
proteomic analysis show that bacterial pathogens respond to EO sublethal doses using known mechanisms of adaptation to
several environmental stress conditions.
The present paper illustrates the basic concepts of PBK modeling. PBK modeling includes six steps... more The present paper illustrates the basic concepts of PBK modeling. PBK modeling includes six steps: (i) definition of the conceptual model, (ii) translation into a mathematical
model, (iii) defining parameter values, (iv) solving the equations, (v) evaluation of model
performance and (vi) making predictions
Alkaloid-containing plants are an intrinsic part of the regular Western diet. The present paper s... more Alkaloid-containing plants are an intrinsic part of the regular Western diet. The present paper summarizes the occurrence of alkaloids in the food chain, their mode of action and possible adverse effects including a safety assessment. Pyrrolizidine alkaloids are a reason for concern because of their bioactivation to reactive alkylating intermediates. Several quinolizidine alkaloids, b-carboline alkaloids, ergot alkaloids and steroid alkaloids are active without bioactivation and mostly act as neurotoxins. Regulatory agencies are aware of the risks and have taken or are considering appropriate regulatory actions for most alkaloids. These vary from setting limits for the presence of a compound in feed, foods and beverages, trying to define safe upper limits, advising on a strategy aiming at restrictions in use, informing the public to be cautious or taking specific plant varieties from the market. For some alkaloids known to be present in the modern food chain, e.g. piperine, nicotine, theobromine, theophylline and tropane alkaloids risks coming from the human food chain are considered to be low if not negligible. Remarkably, for many alkaloids that are known constituents of the modern food chain and of possible concern, tolerable daily intake values have so far not been defined.
Plant antimicrobials fulfil the needs of today’s consumer looking for wholesome food without chem... more Plant antimicrobials fulfil the needs of today’s consumer looking for wholesome food without chemical preservatives.
These can be classified as novel compounds obtained from plants that delay microbial growth of pathogens and spoilage
organisms in food. The antimicrobial activity of plant extracts that is observed in in-vitro conditions is quite different to its
effect in complex food systems. In most cases antimicrobial activity is decreased due to interactions with food
components. This could be a challenge in utilizing plant antimicrobials, as a higher concentration could result in
unfavourable changes to the taste and aroma of food. There is growing scientific evidence of the potential use of plant
antimicrobials for the extension of shelf life in food. This review covers recent trends in using plant antimicrobials in food,
their combination with other technologies, their role in controlling food pathogens and mechanisms of action.
The antimicrobial activity of essential oils and their components has been recognized for a very ... more The antimicrobial activity of essential oils and their components has been recognized for a very long time. Essential oils
(EOs) are made from a very complex mixture of volatile molecules that are produced by the secondary metabolism of
aromatic and medicinal plants and can be obtained by distillation of different parts of plants. The large number of studies on the antimicrobial activity of EOs has allowed the scientific recognition of these compounds on the control of a wide range of microbial pathogens. The progresses made on the investigation of the mode of action of EOs against bacterial cell targets give us new perspectives to combat persistent and antimicrobial resistant bacterial pathogens. The recent
investigation on the activity of EOs disruption of quorum sensing process is an excellent example. On the other hand
proteomic analysis show that bacterial pathogens respond to EO sublethal doses using known mechanisms of adaptation to
several environmental stress conditions.
The present paper illustrates the basic concepts of PBK modeling. PBK modeling includes six steps... more The present paper illustrates the basic concepts of PBK modeling. PBK modeling includes six steps: (i) definition of the conceptual model, (ii) translation into a mathematical
model, (iii) defining parameter values, (iv) solving the equations, (v) evaluation of model
performance and (vi) making predictions
Alkaloid-containing plants are an intrinsic part of the regular Western diet. The present paper s... more Alkaloid-containing plants are an intrinsic part of the regular Western diet. The present paper summarizes the occurrence of alkaloids in the food chain, their mode of action and possible adverse effects including a safety assessment. Pyrrolizidine alkaloids are a reason for concern because of their bioactivation to reactive alkylating intermediates. Several quinolizidine alkaloids, b-carboline alkaloids, ergot alkaloids and steroid alkaloids are active without bioactivation and mostly act as neurotoxins. Regulatory agencies are aware of the risks and have taken or are considering appropriate regulatory actions for most alkaloids. These vary from setting limits for the presence of a compound in feed, foods and beverages, trying to define safe upper limits, advising on a strategy aiming at restrictions in use, informing the public to be cautious or taking specific plant varieties from the market. For some alkaloids known to be present in the modern food chain, e.g. piperine, nicotine, theobromine, theophylline and tropane alkaloids risks coming from the human food chain are considered to be low if not negligible. Remarkably, for many alkaloids that are known constituents of the modern food chain and of possible concern, tolerable daily intake values have so far not been defined.