Esterification of citric acid (CA) with locust bean gum (LBG) was prepared by hydrochloric acid (HCl) as a catalyst and UV irradiation (254 nm) as esterification energy. This study aims to determine the best conditions of esterification. Other than that, it is to know the effect of amount HCl and UV irradiation time for the esterification process of CA with LBG. The amounts of HCl are 0.18 and 0.30 M, while the variations of UV irradiation time are 75 and 100 minutes. Polyester (CA-LBG) were characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffractometer (XRD), esterification degree, and viscosity. Parameters for determining the best conditions for esterification are esterification degree and viscosity. The best conditions of esterification were obtained by using 0.30 M mL HCl and 100 minutes of UV irradiation time resulted in CA-LBG having a value of esterification degree 9.69 % and viscosity 7.46 cPs. HCl accelerates protonation on the O atoms and the formation of positive C atoms of carbonyl groups of citric acid. The time of UV irradiation gives the longer energy for the bond formation between the positive C atoms of the carbonyl group and the O atoms of the hydroxyl group at C-6 atoms of mannose and galactose.

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Introduction: Salicylic acid derivate is very popular for its activity to suppress pain, fever, and inflam ma tion. One of its derivatives is acetylsalicylic acid (ASA) wh ich has be en reported repeatedly that, as a nonsteroidal anti-inflam ma tory drug (NSAID), it has a cardioprotective effect. Although ASA has various advantages, several stud ies have reported that it ma y indu ce severe peptic ulcer disease. We recently synthesized a new compoun d derived from salicylic acid, name ly 2-((3-(chloromethyl)be nz oyl)oxy)be nz oic acid (3 -CH 2 Cl) wh ich still has the be nefit of acetylsalicylic acid as an analgesic and antiplatelet, bu t lacks its harmful side effects (Caroline et al., 20 19 ). In addition, in silico stud ies of 3-CH 2 Cl showed a higher affinity towards protein receptor cyclooxygenase-2 (COX-2; PDB: 5F1A ) than ASA. We hypothesized that 3-CH 2 Cl inhibits the COX-2 activity wh ich could presumably decrease the inflam ma tory responses. However, no knowledge is available on the anti-inflam ma tory response and molecular signaling of this new compoun d. Henc e, in this stud y, we investigated the potential func tional relevanc e of 3-CH 2 Cl in regulating the inflamma tory response in lipopolysacch aride (LPS)-indu ced rats. The results of this stud y show that this compoun d could significantly redu ce the inflam ma tory parame ter in LPS-indu ced rats. Material and methods: Rats were indu ced with LPS of 0.5 mg/kg bw intravenously, prior oral administration with vehicle (3 % Pulvi s Gumm i Arabicum / PGA), 50 0 mg/60 kg body weight (b w; rat dosage converted to hu ma n) of 3-CH 2 Cl and ASA. The inflam ma tory parame ters such as ch anges in the temperature of septic shock, cardiac blood plasma concentrations of IL-1β and TNF-α (ELISA), blood inflam ma tion parame ters, wh ite blood cell concentrations, and lung histopathology were observed. Meanwh ile, the stability of 3-CH 2 Cl powder was evaluated. Result: After the administration of 50 0 mg/60 kg bw of 3-CH 2 Cl (rat dosage converted to hu ma n) to LPSindu ced rats, we observed a significant redu ction of both TNF-α (5 .70+ /-1.04 × 10 3 pg/mL, p= <0 .001 ) and IL-1β (2 .32+ /-0.28 × 10 3 pg/mL, p= <0 .001 ) cardiac blood plasma concentrations. Besides, we foun d a redu ction of wh ite blood cell concentration and the severity of lung injury in the 3-CH 2 Cl group compared to the LPS-indu ced rat group. Ad ditionally, this compoun d ma intained the rat body temperature within norma l limits du ring inflam ma tion, preventing the rats to un dergo septic shock, ch aracterized by hypothermic (t = 12 0 min.) or hyperthermic (t = 36 0 min) conditions. Furthermore, 3-CH 2 Cl was foun d to be stable un til 3 years at 25°C with a relative hu midity of 75 ± 5% . Conclusion: 3-CH 2 Cl compoun d inhibited inflam ma tion in the LPS-indu ced inflam ma tion response model in rats, hypothetically through bind ing to COX-2, and presumably inhibited LPS-indu ced NF-κβ signaling pathways. This stud y could be used as a preliminary hint to investigate the t...