痤疮丙酸杆菌拮抗菌的筛选、发酵优化及安全性评价

Screening,fermentation optimization,and safety evaluation of antagonistic bacteria of Cutibacterium acnes

痤疮是一种毛囊皮脂腺单位的皮肤炎症,青少年患病率可达85%,它的发病与痤疮丙酸杆菌的定植有关。获取能够高效拮抗痤疮丙酸杆菌的微生物,丰富痤疮丙酸杆菌拮抗菌的资源库。采用琼脂扩散法从酸菜中筛选出对痤疮丙酸杆菌具有较强抑菌活性的菌株。通过菌落形态、生化鉴定和16S rDNA序列比对进行菌株鉴定。从培养基优化及发酵条件优化两方面提升拮抗菌的抑菌活性。采用体外安全评价方法评估拮抗菌的安全性。筛选得到一株能高效拮抗痤疮丙酸杆菌的菌株HA2,初步鉴定为海恩西芽孢杆菌(Bacillus haynesii)。通过优化菌株HA2的发酵条件,将过膜发酵上清液抑菌圈的直径从38 mm提升至53 mm。根据四环素效价曲线换算,效价从20308.6 U提升至112927.6 U,提升5.56倍。经体外安全评价,初步判断菌株HA2为安全菌株。海恩西芽孢杆菌HA2是一株能高效拮抗痤疮丙酸杆菌,且成功通过体外安全评价的菌株,具有进一步研究的价值。

Acne is an inflammatory skin condition of the sebaceous units of the hair follicles,with a prevalence of up to 85% in adolescents,which is associated with the colonization of Cutibacterium acnes.To obtain microorganisms that can efficiently antagonize C.acnes and enrich the resource base of C.acnes antagonists.Agar diffusion method was used to screen the strains with strong antibacterial activity against C.acnes from sauerkraut.The strain was identified by colony morphology,biochemical identification,and 16S rDNA gene sequence comparison.The antibacterial activity of the antagonistic bacteria was enhanced by optimizing the culture medium and fermentation conditions.In vitro safety evaluation methods were used to assess the safety of antagonistic bacteria.A strain HA2 was screened for its ability to efficiently antagonize C.acnes and was initially identified as Bacillus haynesii.By optimizing the fermentation conditions of strain HA2,the diameter of the fermentation supernatant inhibition circle was increased from 38 mm to 53 mm.According to the conversion of the tetracycline potency curve,the potency increased from 20 308.6 U to 112 927.6 U,resulting in a 5.56-fold increase.After in vitro safety evaluation,strain HA2 was initially judged to be a safe strain.The Bacillus haynesii HA2 is a strain that can efficiently antagonize C.acnes and has successfully passed the in vitro safety evaluation,which is valuable for further research.