l-Glutaminase is an amidohydrolase which can act as a vital chemotherapeutic agent against various malignancies. In the present work, l-glutaminase productivity from Aspergillus versicolor Faesay4 was significantly increased by 7.72-fold (from 12.33 ± 0.47 to 95.15 ± 0.89 U/mL) by optimizing submerged fermentation parameters in Czapek’s Dox (CZD) medium including an incubation period from 3 (12.33 ± 0.47 U/mL) to 6 days (23.36 ± 0.58 U/mL), an incubation temperature from 30 °C (23.36 ± 0.49 U/mL) to 25 °C (31.08 ± 0.60 U/mL), initial pH from pH 5.0 (8.49 ± 0.21 U/mL) to pH 7.0 (32.18 ± 0.57 U/mL), replacement of glucose (30.19 ± 0.52 U/mL) by sucrose (48.97 ± 0.67 U/mL) as the carbon source at a concentration of 2.0% (w/v), increasing glutamine concentration as the nitrogen source from 1.0% (w/v, 48.54 ± 0.48 U/mL) to 1.5% (w/v, 63.01 ± 0.60 U/mL), and addition of a mixture of KH₂PO₄ and NaCl (0.5% w/v for both) to SZD as the metal supplementation (95.15 ± 0.89 U/mL). Faesay4 l-glutaminase was purified to yield total activity 13,160 ± 22.76 (U), specific activity 398.79 ± 9.81 (U/mg of protein), and purification fold 2.1 ± 3.18 with final enzyme recovery 57.22 ± 2.17%. The pure enzyme showed a molecular weight of 61.80 kDa, and it was stable and retained 100.0% of its activity at a temperature ranged from 10 to 40 °C and pH 7.0. In our trials, to increase the enzyme activity by optimizing the assay conditions (which were temperature 60 °C, pH 7.0, substrate glutamine, substrate concentration 1.0%, and reaction time 60 min), the enzyme activity increased by 358.8% after changing the assay temperature from 60 to 30 °C and then increased by 138% after decreasing the reaction time from 60 to 40 min. However, both pH 7.0 and glutamine as the substrate remain the best assay parameters for the l-glutaminase activity. When the glutamine in the assay as the reaction substrate was replaced by asparagine, lysine, proline, methionine, cysteine, glycine, valine, phenylalanine, l-alanine, aspartic acid, tyrosine, and serine, the enzyme lost 23.86%, 29.0%, 31.0%, 48.3%, 50.0%, 73.6%, 74.51%, 80.42%, 82.5%, 83.43%, 88.36%, and 89.78% of its activity with glutamine, respectively. Furthermore, Mn²⁺, K⁺, Na⁺, and Fe³⁺ were enzymatic activators that increased the l-glutaminase activity by 25.0%, 18.05%, 10.97%, and 8.0%, respectively. Faesay4 l-glutaminase was characterized as a serine protease enzyme as a result of complete inhibition by all serine protease inhibitors (PMSF, benzamidine, and TLCK). Purified l-glutaminase isolated from Aspergillus versicolor Faesay4 showed potent DPPH scavenging activities with IC₅₀ = 50 μg/mL and anticancer activities against human liver (HepG-2), colon (HCT-116), breast (MCF-7), lung (A-549), and cervical (Hela) cancer cell lines with IC₅₀ 39.61, 12.8, 6.18, 11.48, and 7.25 μg/mL, respectively.

l -谷氨酰胺酶是一种酰胺水解酶，可作为对抗各种恶性肿瘤的重要化学治疗剂。在目前的工作中，来自花曲霉的l-谷氨酰胺酶生产力通过优化 Czapek's Dox (CZD) 培养基中的浸没发酵参数，包括从 3 (12.33 ± 0.47 U/mL) 到 6 天的潜伏期，Faesay4 显着增加了 7.72 倍（从 12.33 ± 0.47 到 95.15 ± 0.89 U/mL） (23.36 ± 0.58 U/mL)，孵育温度从 30 °C (23.36 ± 0.49 U/mL) 到 25 °C (31.08 ± 0.60 U/mL)，初始 pH 从 pH 5.0 (8.49 ± 0.21 U/mL)至 pH 7.0 (32.18 ± 0.57 U/mL)，用蔗糖 (48.97 ± 0.67 U/mL) 作为碳源以 2.0% (w/v) 的浓度替代葡萄糖 (30.19 ± 0.52 U/mL)，增加作为氮源的谷氨酰胺浓度从 1.0% (w/v, 48.54 ± 0.48 U/mL) 到 1.5% (w/v, 63.01 ± 0.60 U/mL)，并加入 KH ₂ PO ₄的混合物和 NaCl（两者均为 0.5% w/v）到 SZD 作为金属补充剂（95.15 ± 0.89 U/mL）。Faesay4 l-谷氨酰胺酶被纯化以产生总活性 13,160 ± 22.76 (U)、比活性 398.79 ± 9.81 (U/mg 蛋白质) 和纯化倍数 2.1 ± 3.18，最终酶回收率为 57.22 ± 2.17%。纯酶的分子量为 61.80 kDa，在 10 至 40 °C 和 pH 7.0 的温度范围内稳定并保持 100.0% 的活性。在我们的试验中，为了通过优化测定条件（温度 60 °C、pH 7.0、底物谷氨酰胺、底物浓度 1.0% 和反应时间 60 分钟）来提高酶活性，在改变实验条件后，酶活性提高了 358.8%。测定温度从 60°C 到 30°C，然后在将反应时间从 60 分钟减少到 40 分钟后增加了 138%。然而，pH 7.0 和谷氨酰胺作为底物仍然是l-谷氨酰胺酶活性。当测定中作为反应底物的谷氨酰胺被天冬酰胺、赖氨酸、脯氨酸、蛋氨酸、半胱氨酸、甘氨酸、缬氨酸、苯丙氨酸、l-丙氨酸、天冬氨酸、酪氨酸和丝氨酸取代时，酶分别减少了23.86%、29.0%、谷氨酰胺分别占其活性的 31.0%、48.3%、50.0%、73.6%、74.51%、80.42%、82.5%、83.43%、88.36% 和 89.78%。此外，锰²⁺，K ⁺，钠⁺和Fe ³⁺是酶促活化剂的是增加了升分别为25.0％，18.05％，10.97％，和8.0％，-glutaminase活性。Faesay4 l由于被所有丝氨酸蛋白酶抑制剂（PMSF、苯甲脒和 TLCK）完全抑制，β-谷氨酰胺酶被表征为丝氨酸蛋白酶。从花曲霉Faesay4 中分离的纯化l-谷氨酰胺酶显示出有效的 DPPH 清除活性，IC ₅₀  = 50 μg/mL 和对人肝 (HepG-2)、结肠 (HCT-116)、乳腺 (MCF-7)、肺 ( A-549) 和宫颈 (Hela) 癌细胞系的 IC _{50 分别为}39.61、12.8、6.18、11.48 和 7.25 μg/mL。