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            <front>

                <journal-meta>
                                                                <journal-id>int j. life sci. biotechnol.</journal-id>
            <journal-title-group>
                                                                                    <journal-title>International Journal of Life Sciences and Biotechnology</journal-title>
            </journal-title-group>
                                        <issn pub-type="epub">2651-4621</issn>
                                                                                            <publisher>
                    <publisher-name>International Society of Academicians</publisher-name>
                </publisher>
                    </journal-meta>
                <article-meta>
                                        <article-id pub-id-type="doi">10.38001/ijlsb.1824289</article-id>
                                                                <article-categories>
                                            <subj-group  xml:lang="en">
                                                            <subject>Microbiology (Other)</subject>
                                                    </subj-group>
                                            <subj-group  xml:lang="tr">
                                                            <subject>Mikrobiyoloji (Diğer)</subject>
                                                    </subj-group>
                                    </article-categories>
                                                                                                                                                        <title-group>
                                                                                                                        <article-title>Carica Papaya Plant Parts Endophytic Bacteria and the Activity of Its Secondary Metabolite Against Klebsiella Species and Staphylococcus aureus</article-title>
                                                                                                                                                                                                <trans-title-group xml:lang="tr">
                                    <trans-title>Carica Papaya Plant Parts Endophytic Bacteria and the Activity of Its Secondary Metabolite Against Klebsiella Species and Staphylococcus aureus</trans-title>
                                </trans-title-group>
                                                                                                    </title-group>
            
                                                    <contrib-group content-type="authors">
                                                                        <contrib contrib-type="author">
                                                                    <contrib-id contrib-id-type="orcid">
                                        https://orcid.org/0000-0002-2076-6690</contrib-id>
                                                                <name>
                                    <surname>Umar</surname>
                                    <given-names>Fatima Jummai</given-names>
                                </name>
                                                                    <aff>Kaduna State University Kaduna State, Nigeria</aff>
                                                            </contrib>
                                                    <contrib contrib-type="author">
                                                                    <contrib-id contrib-id-type="orcid">
                                        https://orcid.org/0000-0002-6273-7601</contrib-id>
                                                                <name>
                                    <surname>Doko</surname>
                                    <given-names>Hassan M. I</given-names>
                                </name>
                                                                    <aff>Ahmadu Bello University, Zaria</aff>
                                                            </contrib>
                                                    <contrib contrib-type="author">
                                                                    <contrib-id contrib-id-type="orcid">
                                        https://orcid.org/0000-0003-3750-9954</contrib-id>
                                                                <name>
                                    <surname>Muhammad Sani</surname>
                                    <given-names>Aliyu</given-names>
                                </name>
                                                                    <aff>Ahmadu Bello University, Zaria</aff>
                                                            </contrib>
                                                    <contrib contrib-type="author">
                                                                    <contrib-id contrib-id-type="orcid">
                                        https://orcid.org/0009-0002-0805-7928</contrib-id>
                                                                <name>
                                    <surname>Ambi</surname>
                                    <given-names>Aminu Adamu</given-names>
                                </name>
                                                                    <aff>Ahmadu Bello University, Zaria</aff>
                                                            </contrib>
                                                                                </contrib-group>
                        
                                        <pub-date pub-type="pub" iso-8601-date="20260416">
                    <day>04</day>
                    <month>16</month>
                    <year>2026</year>
                </pub-date>
                                        <volume>9</volume>
                                        <issue>1</issue>
                                        <fpage>270</fpage>
                                        <lpage>276</lpage>
                        
                        <history>
                                    <date date-type="received" iso-8601-date="20251119">
                        <day>11</day>
                        <month>19</month>
                        <year>2025</year>
                    </date>
                                                    <date date-type="accepted" iso-8601-date="20260102">
                        <day>01</day>
                        <month>02</month>
                        <year>2026</year>
                    </date>
                            </history>
                                        <permissions>
                    <copyright-statement>Copyright © 2018, International Journal of Life Sciences and Biotechnology</copyright-statement>
                    <copyright-year>2018</copyright-year>
                    <copyright-holder>International Journal of Life Sciences and Biotechnology</copyright-holder>
                </permissions>
            
                                                                                                <abstract><p>Considerable research has been carried out on medicinal plants for bioactive compounds except bacterial endophytes of plants which could serve as good source of novel antibiotic agents. This study was aimed to determine the antibacterial activity of secondary metabolites of endophytic bacterial isolates of Carica papaya against Klebsiella species and Staphylococcus aureus. Clinical isolates; Klebsiella species and Staphylococcus aureus were confirmed using morphological and biochemical standards. Bacterial endophytes were also cultured, isolated and identified using morphological and biochemical tests and the endophytes isolated designated as PL, PS, PR1 and PR2 which were all Gram negative rod. The bacterial endophyte PL1 was presumed to be Flavobacterium species, Enterobacter species for PS and PR1 while Proteus species for PR2. The endophytes were screened for bioactive secondary metabolites with antibacterial activity using ethyl acetate extract and agar well-diffusion method. Secondary metabolites from PS and PR2 showed strong antibacterial activity against Klebsiella species only with zones of inhibition of 18mm and 22mm respectively while that of PL and PR1 showed no zones of inhibition against both clinical isolates. Ethyl acetate extract of secondary metabolite was then subjected to phytochemical screening where flavonoid and phenol were detected and confirmed using Thin Layer chromatography (TLC) plates developed in ethyl acetate and Methanol chamber (8:2). Flavonoid and Phenol are known to possess antibacterial activities and as such could be responsible for the antibacterial activity against the clinical isolates. Therefore, bacterial endophytes from Carica papaya root could serve as a good source for the development of therapeutic drugs.</p></abstract>
                                                                                                                                    <trans-abstract xml:lang="tr">
                            <p>Considerable research has been carried out on medicinal plants for bioactive compounds except bacterial endophytes of plants which could serve as good source of novel antibiotic agents. This study was aimed to determine the antibacterial activity of secondary metabolites of endophytic bacterial isolates of Carica papaya against Klebsiella species and Staphylococcus aureus. Clinical isolates; Klebsiella species and Staphylococcus aureus were confirmed using morphological and biochemical standards. Bacterial endophytes were also cultured, isolated and identified using morphological and biochemical tests and the endophytes isolated designated as PL, PS, PR1 and PR2 which were all Gram negative rod. The bacterial endophyte PL1 was presumed to be Flavobacterium species, Enterobacter species for PS and PR1 while Proteus species for PR2. The endophytes were screened for bioactive secondary metabolites with antibacterial activity using ethyl acetate extract and agar well-diffusion method. Secondary metabolites from PS and PR2 showed strong antibacterial activity against Klebsiella species only with zones of inhibition of 18mm and 22mm respectively while that of PL and PR1 showed no zones of inhibition against both clinical isolates. Ethyl acetate extract of secondary metabolite was then subjected to phytochemical screening where flavonoid and phenol were detected and confirmed using Thin Layer chromatography (TLC) plates developed in ethyl acetate and Methanol chamber (8:2). Flavonoid and Phenol are known to possess antibacterial activities and as such could be responsible for the antibacterial activity against the clinical isolates. Therefore, bacterial endophytes from Carica papaya root could serve as a good source for the development of therapeutic drugs.</p></trans-abstract>
                                                            
            
                                                            <kwd-group>
                                                    <kwd>antibacterial</kwd>
                                                    <kwd>  bacterial endophytes</kwd>
                                                    <kwd>  Carica papaya</kwd>
                                                    <kwd>  clinical isolates</kwd>
                                                    <kwd>  secondary metabolites</kwd>
                                            </kwd-group>
                                                        
                                                                            <kwd-group xml:lang="tr">
                                                    <kwd>antibacterial</kwd>
                                                    <kwd>  bacterial endophytes</kwd>
                                                    <kwd>  Carica papaya</kwd>
                                                    <kwd>  clinical isolates</kwd>
                                                    <kwd>  secondary metabolites</kwd>
                                            </kwd-group>
                                                                                                            </article-meta>
    </front>
    <back>
                            <ref-list>
                                    <ref id="ref1">
                        <label>1</label>
                        <mixed-citation publication-type="journal">1.	Kushwaha, M.S., A. Nayak, A.K. Rai, and et al., Antibacterial Potential of Fungal Endophytes Isolated from Carica papaya. Indian Journal of Animal Research, 2023. 57(8): p. 1079-1084. Doi:10.18805/IJAR.B-4354
2.	Singh, A.K., R.K. Sharma, V. Sharma, T. Sharma, and D. Kumari, Isolation, morphological identification and in vitro antibacterial activity of endophytic bacteria isolated from Morus nigra (mulberry) leaves. Journal of Animal Research, 2017. 7(1): p. 155-164
3.	Saleem, M., M.T. Cheema, A. Hassan, S. Shaukat, and I. Sajid, Endophytes and Plant Extracts of Carica papaya Linn. Exhibit Promising Antibacterial and in vitro Antitumor Activity. The Journal of Animal &amp; Plant Sciences, 2020. 30(4): p. 1037-1046
4.	Morare, R.F., E. Ubomba-Jaswa, and M.H. Serepa-Dlamini, Isolation and identification of bacterial endophytes from Crinum macowanii Baker. African Journal of Biotechnology, 2018. 17(33): p. 1040-1047. Doi:10.5897/AJB2017.16350</mixed-citation>
                    </ref>
                            </ref-list>
                    </back>
    </article>
