Harmony in detoxification: Microalgae unleashing the potential of lignocellulosic pretreatment wastewater for resource utilization

Lignocellulosic biomass is a pivotal renewable resource in biorefinery process, requiring pretreatment, primarily chemical pretreatment, for effective depolymerization and subsequent transformation. This process yields solid residue for saccharification and lignocellulosic pretreatment wastewater (LPW), which comprises sugars and inhibitors such as phenols and furans. This study explored the microalgal capacity to treat LPW, focusing on two key hydrolysate inhibitors: furfural and vanillin, which impact the growth of six green microalgae. Chlorella sorokiniana exhibited higher tolerance to furfural and vanillin. However, both inhibitors hindered the growth of C. sorokiniana and disrupted algal photosynthetic system, with vanillin displaying superior inhibition. A synergistic inhibitory effect (Q < 0.85) was observed with furfural and vanillin on algal growth. Furfural transformation to low-toxic furfuryl alcohol was rapid, yet the addition of vanillin hindered this process. Vanillin stimulated carbohydrate accumulation, with 50.48 % observed in the 0.1 g/L furfural + 0.1 g/L vanillin group. Additionally, vanillin enhanced the accumulation of C16: 0 and C18: 2, reaching 21.71 % and 40.36 %, respectively, with 0.1 g/L vanillin. This study proposed a microalgae-based detoxification and resource utilization approach for LPW, enhancing the comprehensive utilization of lignocellulosic components. The observed biomass modifications also suggested potential applications for biofuel production, contributing to the evolving landscape of sustainable biorefinery processes.

Unveiling the Potential of Algal Extracts as Promising Antibacterial and Antibiofilm Agents against Multidrug-Resistant Pseudomonas aeruginosa: In Vitro and In Silico Studies including Molecular Docking

Multidrug-resistant Pseudomonas aeruginosa poses a global challenge due to its virulence and biofilm-forming ability, leading to persistent infections. This study had a dual focus: first, it aimed to investigate the biofilm activity and antibiotic resistance profiles of Pseudomonas aeruginosa isolates obtained from a fish-rearing farm. Second, it explored the potential of algal extracts as effective antibacterial and antibiofilm agents. The study analyzed 23 isolates of P. aeruginosa from the farm, assessing antibiotic resistance and biofilm formation. The antimicrobial and antibiofilm activities of two algal extracts, Arthrospira platensis (cyanobacteria) acetone extract (AAE) and Polysiphonia scopulorum (Rhodophyta) methanol extract (PME), were tested individually and combined (COE). The effects on biofilm-related gene expression were examined. AAE, PME, and COE were evaluated for antimicrobial and antibiofilm properties. Biofilm-related gene expression was measured and the extracts were analyzed for physicochemical properties and toxicity. Most P. aeruginosa isolates (86.9%) were antibiotic-resistant and formed biofilms. AAE, PME, and COE displayed promising antibacterial and antibiofilm effects, with COE being particularly effective. COE reduced a key biofilm-related gene expression. The fatty acid content (56% in AAE and 34% in PME) correlated with the effects. Specific compounds, such as phytol, bromophenol, and dihydroxy benzaldehyde, contributed to the activities. The extracts showed favorable characteristics and interactions with FabZ protein amino acids. This study suggests the potential of algal extracts as antibacterial and antibiofilm agents against drug-resistant infections. Further exploration in clinical applications is warranted.

Application of a novel biological-nanoparticle pretreatment to Oscillatoria acuminata biomass and coculture dark fermentation for improving hydrogen production

BACKGROUND

Energy is the basis and assurance for a world's stable development; however, as traditional non-renewable energy sources deplete, the development and study of renewable clean energy have emerged. Using microalgae as a carbon source for anaerobic bacteria to generate biohydrogen is a clean energy generation system that both local and global peers see as promising.

RESULTS

Klebsiella pneumonia, Enterobacter cloacae, and their coculture were used to synthesize biohydrogen using Oscillatoria acuminata biomass via dark fermentation. The total carbohydrate content in O. acuminata was 237.39 mg/L. To enhance the content of fermentable reducing sugars, thermochemical, biological, and biological with magnesium zinc ferrite nanoparticles (Mg-Zn Fe₂O₄-NPs) pretreatments were applied. Crude hydrolytic enzymes extracted from Trichoderma harzianum of biological pretreatment were enhanced by Mg-Zn Fe₂O₄-NPs and significantly increased reducing sugars (230.48 mg/g) four times than thermochemical pretreatment (45.34 mg/g). K. pneumonia demonstrated a greater accumulated hydrogen level (1022 mLH₂/L) than E. cloacae (813 mLH₂/L), while their coculture showed superior results (1520 mLH₂/L) and shortened the production time to 48 h instead of 72 h in single culture pretreatments. Biological pretreatment + Mg-Zn Fe₂O₄ NPs using coculture significantly stimulated hydrogen yield (3254 mLH₂/L), hydrogen efficiency)216.9 mL H₂/g reducing sugar( and hydrogen production rate (67.7 mL/L/h) to the maximum among all pretreatments.

CONCLUSION

These results confirm the effectiveness of biological treatments + Mg-Zn Fe₂O₄-NPs and coculture dark fermentation in upregulating biohydrogen production.

Predictors of non-invasive ventilation failure in adult patients with cardiac dysfunction presenting with community acquired pneumonia; an Egyptian multicenter prospective study

Funding Acknowledgements

Type of funding sources: None.

Background

Non-invasive ventilation (NIV) might be successful if properly selected in adult patients with cardiac dysfunction presenting with community acquired pneumonia. The main objective was to identify contributing factors to NIV failure.

Methods

All adult patients with LV EF less than 50% admitted to the ICU with community acquired pneumonia and acute respiratory failure were enrolled in our multicenter prospective study after getting informed consents . The study was registered and given a number (ID ISRCTN14641518). Non-invasive ventilation failure was defined as requirement of intubation after institution of NIV intervention.

Results

We prospectively enrolled 177 patients between February 2019 to July 2020. Fifty-three patients (29.9%) were considered failed NIV. The mean age of studied patients was 64.1±12.6 years with a male predominance (73.4%) and a mean left ventricle EF of 36.4±7.8%. There were insignificant differences between the NIV success and NIV failure groups regarding the underlying morbidities nor the inflammatory markers. The patients who failed NIV were significantly older with higher mean SOFA and APACHE II scores compared to the patients with succeeded NIV. Non-invasive Ventilation failure was associated with longer ICU stay (p&lt;0.001), higher SOFA at 48 hours (p&lt;0.001) and higher mortality (p&lt;0.001) compared to the NIV success group. NIV failure was independently predicted with APACHE II (OR:1.420, p 0.01, 95% CI:1.224 – 1.647), SOFA (OR:17.6 , p &lt;0.001, 95% CI: 4.148-74.68), baseline HACOR (OR:2.041, P 0.026, 95% CI:1.225 –3.401), lung ultrasound score (OR:1.209,P 0.017,95% CI:1.014–1.441) and blood lactate (OR:9.702,P &lt;0.001,95%CI:1.357–69.37).Conclusion: High initial APACHE II and SOFA scores , hindered lactate clearance as well as non-decrementing patterns of HACOR and LUS scores were associated with early NIV failure in patients with heart failure presenting with community acquired pneumonia.

Epidemiology of hilar cholangiocarcinoma in Egypt: single center study

BACKGROUND/AIMS

Cholangiocarcinoma is the second most frequent malignant tumor of the liver after hepatocellular carcinoma. The incidence rates of hilar cholangiocarcinoma (CC) vary greatly among different areas of the world, this variation is related to distribution of risk factors. The aim of this work is to study epidemiology and possible risk factors in the North East delta of Egypt.

METHODOLOGY

This study included 440 patients with hilar cholangiocarcinoma who were admitted to the Gastrointestinal Surgical Center, Mansoura University between January 1995 and October 2004. After complete evaluation by thorough history, clinical examination, biochemical assessment including liver function tests, kidney function tests, blood picture and serology of viral markers, tumor markers and radiological investigation.

RESULTS

The mean age was 54.49 +/- 12.8 (range 23 to 82 year). Male to female ratio was 1.7:1, with increasing annual incidence from 22 patients at 1995 up to 68 patients in 2003 and 60 patients in the first 10 months of 2004. Hilar CC is common in patients coming from rural areas especially in Dakahlia government area (41%). All patients presented with jaundice, while weight loss was presented in 41%, and right upper abdominal pain in 37% of patients. Positive history of schistosomiasis infection was encountered in 66.5% while typhoid infection was in 52% of patients with high prevalence of both in rural versus urban (89% vs. 13%, p < 0.001 & 66% vs. 25%, p < 0.001). Laboratory assessment revealed 238 (54%) patients HCV positive while HBs antigen positive in 10 (2%) with high significant increase of HCV in rural versus urban (70% vs. 16%, p < 0.001). Gallstones was significantly higher in rural versus urban (28% vs. 40%, p = 0.016). The laboratory data showed highly significant increase in serum alkaline phosphatase, CA19.9 (26.9 +/- 1 4.4mg/dL, 56.3 +/- 30.6 KAU, 517.8 +/- 279.2 u/mL respectively).

CONCLUSIONS

We conclude that, the number of newly diagnosed cases increases annually, it is common in males especially in farmers and rural residents. Liver cirrhosis, HCV, bilharziasis, chronic typhoid infection and gallstones can be possible risk factors for hilar cholangiocarcinoma in Egypt.

Resectability and prognostic factors after resection of hilar cholangiocarcinoma

BACKGROUND/AIMS

Hilar cholangiocarcinoma, still a challenging problem for surgeons and resectional surgery, is the treatment of choice for long-term survival. In this study we tried to evaluate different prognostic factors after resection.

METHODOLOGY

From January 1995 to October 2004, 440 patients with hilar cholangiocarcinoma were admitted to the Gastroenterology Surgical Center, Mansoura University, Egypt. Of these patients 73 underwent potentially curative resection giving respectability rate of 17%, and the remaining 367 patients underwent non-surgical treatment because of advanced disease, advanced cirrhosis and poor general condition. Of the 73 patients, 35 (48%) underwent localized hepatic resection and 38 (52%) patients underwent major hepatic resection. Various prognostic factors for survival were evaluated by univariate and multivariate analysis.

RESULTS

Hospital mortality occurred in 8 (11%) patients. The most common postoperative complications were: bile leak, liver cell failure and wound infection 23.2%, 17.8% and 9.5% respectively. The survival rates at 1, 2, 3, 4, and 5 years were 79%, 32.6, 18.5, 137% and 13% respectively. The result of univariate analysis revealed that radicality of resection, lymph nodes status, tumor differentiation, modified Bismuth staging, underlying liver pathology, HCV viral infection, blood transfusion, preoperative serum bilirubin <10mg and CA19-9 are dependent prognostic factors. By multivariate Cox analysis radicality of resection, lymph nodes status, serum bilirubin below 10mg/dL level of CA19-9 and hepatitis viral infection were independent predictor factors.

CONCLUSIONS

From this study we found that aggressive surgical procedure to obtain curative resection with preoperative serum bilirubin below 10mg and HCV infective negative especially in noncirrhotic liver may bring a better prognosis in hilar cholangiocarcinoma.

Primary hepatic carcinoid tumor: one Egyptian center experience

BACKGROUND/AIMS

Carcinoid tumors of the liver are rare and pose both a diagnostic and therapeutic dilemma. Our aim was to study the diagnosis and treatment of primary hepatic carcinoid and to highlight its incidence in relation to hepatocellular carcinoma in our series and review of literature.

METHODOLOGY

Between March 1992 and May 2005, we managed 5 patients (1 male, 4 females) with primary hepatic carcinoid in our center.

RESULTS

The main presentation was upper abdominal pain with palpable mass, while in one patient tumor was discovered accidentally, none of them had carcinoid syndrome. The tumors were located in the left lobe in one patient, caudate lobe in two patients and right lobe in two patients. The diagnosis was confirmed histologically with light microscopy and immunohistochemistry. Four patients remain alive and disease free after follow-up of 72, 18, 16, and 4 months. One patient died after 11 years of follow-up with recurrence after 10 years, with mean follow-up of 45.2 +/- 53.1 months in May 2005.

CONCLUSIONS

Primary hepatic carcinoid tumor is rare. It occurs on top of non-cirrhotic liver. Hepatic resection even in large-sized tumor is the treatment of choice.

Outcome after resection of central cholangiocarcinoma: preliminary experience with 46 patients in a single center

BACKGROUND/AIMS

Despite the enormous progress in surgery the management of cholangiocarcinoma remains a problem. In this study we present our preliminary experience in the surgical treatment of central cholangiocarcinoma.

METHODOLOGY

Between May 1997 and December 2001, 175 patients with central cholangiocarcinoma were admitted to our center. Of the 175 patients, 54 cases subjected to surgery, the remaining 131 patients did not undergo surgery because of advanced disease, advanced liver cirrhosis and poor general condition. Forty-six patients underwent surgical excision, their mean age was 53 +/- 3 years, and male to female ratio was 74-26%. All patients presented with jaundice associated with pain (30%) or biliary stones (32%). Surgical resection of the bile duct with or without part of segment IV were done in fourteen patients and bile duct resection together with major hepatectomy had been done in the remaining 28 patients.

RESULTS

Hospital mortality occurred in 10.8%; the main cause of mortality was hepatic cell failure. The most common complications were hepatic cell failure that occurred in 7 cases (15%), biliary leakage in 8 cases (17%), gastrointestinal bleeding in 3 cases (6.5%) and wound infection in 3 cases (6.5%). Late complication in the form of recurrence occurred in 12 cases (29.5%). cholangitis in 8 cases (19.5%), hepatic cell failure in 5 (12%) and gastrointestinal bleeding in 2 (4.8%). At the end of the study, 19 patients (46%) were alive with mean follow-up of 16.6 +/- 9 months. The survival rate at 6, 12, 18, 24 months was 92, 82, 52, 25, 18%, respectively. Recurrence and cholangitis were found significantly higher in the group without hepatectomy than the group after hepatectomy (p < 0.0001, p < 0.0016, respectively).

CONCLUSIONS

From our results we can conclude that major hepatectomy with excision of the extrahepatic bile duct system and caudate lobe resection may be recommended for the surgical treatment of central cholangiocarcinoma in selected cases.