Porcine placenta hydrolysate as an alternate functional food ingredient: In vitro antioxidant and antibacterial assessments

Phanthipha Laosam; Worawan Panpipat; Gorawit Yusakul; Ling-Zhi Cheong; Manat Chaijan

doi:10.1371/journal.pone.0258445

Peer Review History

Original SubmissionJune 8, 2021
24 Aug 2021 Decision Letter - Saikat Dewanjee, Editor PONE-D-21-18837 Porcine placenta hydrolysate as an alternate functional food ingredient PLOS ONE Dear Dr. Panpipat, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please submit your revised manuscript by Oct 04 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. 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I also suggest including more references from the same journal and replace old references. [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Yes Reviewer #2: Yes Reviewer #3: Partly Reviewer #4: Partly ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: Yes Reviewer #3: N/A Reviewer #4: Yes ****** 3. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: Yes Reviewer #2: Yes Reviewer #3: Yes Reviewer #4: No ****** 4. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes Reviewer #2: Yes Reviewer #3: No Reviewer #4: No ****** 5. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: The presented manuscript, "Porcine placenta hydrolysate as an alternate functional food ingredient" seems okay. It will be very good if the authors go for thorough language checking prior publishing the article. Reviewer #2: The manuscript entitled "Porcine placenta hydrolysate as an alternate functional food ingredient" describes the food functional values and antioxidant activities of Porcine placenta hydrolysate. The manuscript has been nicely represented with significant scientific work. Some figures are not clear to understand properly. English editing is needed since there are many Grammatical errors in the manuscript. Statistical significance should be included in the figure 1 to figure 4. After these changes, manuscript may be accepted for the publication. Reviewer #3: The work done by Worawan Panpipat et al., entitled “Porcine placenta hydrolysate as an alternate functional food ingredient” is too preliminary for any scientific conclusion. There are few comments that need to be properly addressed before further progress of the manuscript. 1.The author should find out the effect of hydrolysate in invivo/ invitro model. 2.The author should also perform some additional experiment to established anti-microbial and antioxidative properties. 3.The author should provide appropriate figure legends. 4.Author should go through the manuscript thoroughly to check the typographical errors and grammatical mistakes. Reviewer #4: 1. Restructure Ln 52, 53, 54 2. Ln 56, 57 do not have citation 3. Ln 63, 63 has poor English, need correction 4. rationale of the study is not appropriate in the given interest 5. Mention Cat# for all the reagents/Chemicals, and other consumables. 6. All experiments were carried out in triplicate (N = 3), does it satisfy power of the study 7. Figure Legends needs to re-write and not conveying required information 8. anti-microbial and anti-oxidant properties are not established properly ****** 6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review?** For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #1: No Reviewer #2: No Reviewer #3: No Reviewer #4: No [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0258445.r001
Revision 1
28 Aug 2021 Author Response Response to Reviewers All points raised by the reviewers were carefully addressed and answered point-by-point. A revision was made in highlighted red fonts. The revised manuscript was carefully prepared to meet PLOS ONE's style requirements. Journal Requirements: When submitting your revision, we need you to address these additional requirements. 1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf Ans: The revised manuscript was carefully prepared to meet PLOS ONE's style requirements. 2. PLOS requires an ORCID iD for the corresponding author in Editorial Manager on papers submitted after December 6th, 2016. Please ensure that you have an ORCID iD and that it is validated in Editorial Manager. To do this, go to ‘Update my Information’ (in the upper left-hand corner of the main menu), and click on the Fetch/Validate link next to the ORCID field. This will take you to the ORCID site and allow you to create a new iD or authenticate a pre-existing iD in Editorial Manager. Please see the following video for instructions on linking an ORCID iD to your Editorial Manager account: https://www.youtube.com/watch?v=_xcclfuvtxQ Ans: The ORCID iD for the corresponding author is given. 3. We suggest you thoroughly copyedit your manuscript for language usage, spelling, and grammar. If you do not know anyone who can help you do this, you may wish to consider employing a professional scientific editing service. Ans: QuillBot, a paraphrase tool, was used to double-check the language throughout the manuscript. Reviewer #1: The presented manuscript, "Porcine placenta hydrolysate as an alternate functional food ingredient" seems okay. It will be very good if the authors go for thorough language checking prior publishing the article. Ans: QuillBot, a paraphrase tool, was used to double-check the language. Reviewer #2: The manuscript entitled "Porcine placenta hydrolysate as an alternate functional food ingredient" describes the food functional values and antioxidant activities of Porcine placenta hydrolysate. The manuscript has been nicely represented with significant scientific work. Some figures are not clear to understand properly. English editing is needed since there are many Grammatical errors in the manuscript. Statistical significance should be included in the figure 1 to figure 4. After these changes, manuscript may be accepted for the publication. Ans: The Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/, was used to check the quality of all figures. We double-checked that the figures complied with PLOS guidelines. QuillBot, a paraphrase tool, was used to double-check the language. All figures and tables were statistically analyzed, as stated in the text. The letters indicating statistical differences, on the other hand, were not included in the figures since they would make the figures too cluttered. Reviewer #3: The work done by Worawan Panpipat et al., entitled “Porcine placenta hydrolysate as an alternate functional food ingredient” is too preliminary for any scientific conclusion. There are few comments that need to be properly addressed before further progress of the manuscript. 1.The author should find out the effect of hydrolysate in in vivo/ in vitro model. Ans: The statement and its significance were given in the Abstract. “The production of bioactive peptides from animal-based raw materials highly depends on enzymatic hydrolysis. Porcine placenta is an underutilized biomass in Thailand's pig farms, yet it is still a source of proteins and beneficial compounds. Porcine placenta could be used as a protein substrate for the production of enzymatic hydrolysate, which could be employed as a functional food ingredient in the future. The goal of this study was to enzymatically produce porcine placenta hydrolysates (PPH) using three commercial enzymes (Alcalase, Flavouzyme, and papain) and evaluate their in vitro antioxidant and antibacterial activity.”. As a result, the antioxidant and antibacterial properties were investigated in vitro in this work. This study did not contain any in vivo testing. So the title was changed to “Porcine placenta hydrolysate as an alternate functional food ingredient: in vitro antioxidant and antibacterial assessments” to make it more apparent. In vitro tests can be performed to examine the bioactivity of active compounds such as protein hydrolysate, which is particularly useful in the area of Food Science and Technology. 2. The author should also perform some additional experiment to established anti-microbial and antioxidative properties. Ans: The antibactial and antioxidant capabilities were tested and reported in the original manuscript. The antioxidant activities were exhibited, which included DPPH•/ABTS•+ scavenging activities (Fig. 2), reducing power (Fig. 3) and metal chelating activity (Fig. 3). Table 2 also includes the correlation coefficient between enzymatic hydrolytic variables and antioxidant activities of porcine placenta hydrolysate. In addition, the gastrointestinal (GI) tract model system was used to investigate changes in DPPH•/ABTS•+ scavenging activities and reducing power. The antibacterial activity of PPH was examined using the agar-well diffusion method against Staphylococcus aureus and Escherichia coli, and the zone of inhibition was reported. All of the tests can be used to draw conclusions about porcine placenta hydrolysate's antioxidant and antibacterial activities. 3.The author should provide appropriate figure legends. Ans. All of the legends for the figures were double-checked. 4.Author should go through the manuscript thoroughly to check the typographical errors and grammatical mistakes. Ans: QuillBot, a paraphrase tool, was used to check for typographical errors and recheck the language. Reviewer #4: 1. Restructure Ln 52, 53, 54 Ans: It was changed to “Wastes and by-products are being reassembled in the farrow-to-finish production pig farming system, which consists of breeding pigs, producing piglets, and fattening pigs, as a result of the expansion of large-scale pig farms [3].” 2. Ln 56, 57 do not have citation Ans: Because no research has been documented in Thailand, no references were provided. Therefore, the sentence was changed to “However, there has been no published research on the use of pig placenta in Thailand. It is of great interest to figure out how to use the right technologies to add value to this placenta.” 3. Ln 63, 63 has poor English, need correction Ans: It was changed to “Collagen is the most abundant protein in the extracellular matrix of the placenta, with lately high market values [4, 5, 6].” 4. rationale of the study is not appropriate in the given interest Ans: The rationale of the study was intensively revised as highlighted in the Introduction. 5. Mention Cat# for all the reagents/Chemicals, and other consumables. Ans: It was stated in the “Chemical” section that “All enzymes (Alcalase from Bacillus licheniformis, Flavourzyme from Aspergillus oryzae protease, papain from papaya latex) and chemicals (e.g., trichloroacetic acid (TCA), 2,4,6-trinitrobenzene sulfonic acid (TNBS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 3-(2-pyridyl)-5-6-diphenyl-1,2,4-triazine-4′,4′′-disulphonic acid sodium salt (ferrozine), 2,2-azino-bis(3-thylbenzothiazoline-6-sulphonicacid) diammonium salt (ABTS), 2,4,6-tripyridyl-s-triazine (TPTZ)) were purchased from Sigma-Aldrich (St. Louis, MO, USA).”. It met the journal's requirements, and many standard journals do not require the Cat#. As a result, we didn't include the Cat#. Thank you very much. 6. All experiments were carried out in triplicate (N = 3), does it satisfy power of the study Ans: All experiments were run in triplicate with three different lots of placenta (N = 3). As a result, the study's power was satisfied. 7. Figure Legends needs to re-write and not conveying required information Ans: The figure legends were revised accordingly. 8. anti-microbial and anti-oxidant properties are not established properly Ans: The antioxidant activities were tested, which included DPPH•/ABTS•+ scavenging activities (Fig. 2), reducing power (Fig. 3) and metal chelating activity (Fig. 3). Table 2 also includes the correlation coefficient between enzymatic hydrolytic variables and antioxidant activities of porcine placenta hydrolysate. In addition, the gastrointestinal (GI) tract model system was used to investigate changes in DPPH•/ABTS•+ scavenging activities and reducing power. The antibacterial activity of PPH was examined using the agar-well diffusion method against Staphylococcus aureus and Escherichia coli, and the zone of inhibition was reported. All of the tests can be used to draw conclusions about porcine placenta hydrolysate's antioxidant and antibacterial activities. While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. Ans: Done. Attachments Attachment Submitted filename: Response to Reviewers.docx https://doi.org/10.1371/journal.pone.0258445.r002
28 Sep 2021 Decision Letter - Saikat Dewanjee, Editor Porcine placenta hydrolysate as an alternate functional food ingredient: in vitro antioxidant and antibacterial assessments PONE-D-21-18837R1 Dear Dr. Panpipat, We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements. Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication. An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Saikat Dewanjee Academic Editor PLOS ONE Additional Editor Comments (optional): Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation. Reviewer #2: All comments have been addressed Reviewer #3: All comments have been addressed ******** 2. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #2: Yes Reviewer #3: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #2: Yes Reviewer #3: I Don't Know ****** 4. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #2: (No Response) Reviewer #3: (No Response) ****** 5. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #2: Yes Reviewer #3: No ****** 6. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #2: (No Response) Reviewer #3: (No Response) ****** 7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #2: No Reviewer #3: Yes:** Parames C. Sil https://doi.org/10.1371/journal.pone.0258445.r003
Formally Accepted
7 Oct 2021 Acceptance Letter - Saikat Dewanjee, Editor PONE-D-21-18837R1 Porcine placenta hydrolysate as an alternate functional food ingredient: in vitro antioxidant and antibacterial assessments Dear Dr. Panpipat: I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department. If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org. If we can help with anything else, please email us at plosone@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr Saikat Dewanjee Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0258445.r004

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