The study used an aqueous extract prepared without chemical or enzymatic pretreatment. Fresh bagasse collected from sugarcane juice vendors in Haldia, West Bengal, was cut into approximately 1-inch pieces, and 5 grams were added to 200 millilitres of distilled water. The suspension was heated at 95–100 °C for 30 minutes, cooled to room temperature and filtered through muslin cloth to remove coarse solids. Previous measurements cited by the researchers placed the extract’s reducing sugar concentration at approximately 0.764 grams per litre and its total soluble sugar concentration at about 10 grams per litre. Individual sugars such as glucose, fructose and sucrose were not separately identified in the present study, so the Lane–Eynon result was a bulk estimate of total soluble sugars rather than a detailed sugar profile. Fermentation took place at pH 4.0, 30.20 °C and 6% inoculum for 22.06 hours, using conditions established in the researchers’ earlier work.

Fourier transform infrared spectroscopy indicated that the extract contained functional groups associated with cellulose, hemicellulose and lignin. A broad band between 3200 and 3400 inverse centimetres was attributed to O–H stretching, a feature near 2920 inverse centimetres to aliphatic C–H stretching, and bands between 1000 and 1150 inverse centimetres to C–O and C–O–C vibrations associated with glycosidic linkages. These observations supported the presence of carbohydrate-rich structural material in the extract, although FTIR alone could not identify or quantify individual sugars. The extract supported some fermentation, but its limited ethanol production suggested that carbohydrate-associated components alone were insufficient to sustain high productivity under the tested conditions without additional nutrients.

Researchers screened potential supplements using a one-variable-at-a-time design while holding the fermentation conditions constant. Glucose, fructose and sucrose were each tested at 1% weight per volume as carbon sources; ammonium chloride, ammonium sulfate and urea were each tested at 1% as nitrogen sources; and magnesium sulfate, ferrous sulfate, calcium chloride, potassium chloride and sodium chloride were evaluated at 0.1 milligrams per millilitre as mineral sources. Each condition was tested in triplicate, and treatment means were compared by one-way analysis of variance followed by Fisher’s least significant difference test. An untreated, non-supplemented control was not included contemporaneously in these screening experiments, so the results established relative performance among the tested supplements rather than supplying a direct baseline for every comparison.

Sucrose performed best during the initial carbon-source screen, producing a mean ethanol concentration of 0.605 ± 0.009 grams per 100 millilitres at 1%, compared with 0.558 ± 0.01 for glucose and 0.584 ± 0.005 for fructose. When sucrose concentration was varied, ethanol increased from 0.520 ± 0.006 grams per 100 millilitres at 0.5% to 1.771 ± 0.105 at 4%. Production then declined at higher concentrations, reaching 1.633 ± 0.105 grams per 100 millilitres at 7%. The authors associated this non-linear response with possible osmotic stress or altered metabolic regulation, but they did not directly measure transporter activity, invertase function or metabolic flux, so the physiological basis for the pattern remained unconfirmed. The 4% sucrose level selected for subsequent nitrogen and mineral screening produced more ethanol than any other concentration tested in that series.

Among the nitrogen sources, ammonium sulfate gave the highest mean ethanol concentration when combined with 4% sucrose: 1.598 ± 0.189 grams per 100 millilitres, compared with 1.253 ± 0.071 for ammonium chloride and 0.425 ± 0.468 for urea. Ammonium sulfate and ammonium chloride did not differ significantly in that screening, but ammonium sulfate was carried forward because it had the higher mean. Varying its concentration produced a maximum of 1.897 ± 0.03 grams per 100 millilitres at 0.5%, while further additions reduced ethanol production. Potassium chloride similarly outperformed the other minerals under the conditions tested, yielding 1.598 ± 0.05 grams per 100 millilitres at 0.1 milligrams per millilitre, versus 1.242 ± 0.03 for magnesium sulfate, 1.138 ± 0.1 for calcium chloride, 1.092 ± 0.13 for ferrous sulfate and 0.966 ± 0.12 for sodium chloride.

The three strongest supplements—sucrose, ammonium sulfate and potassium chloride—were then optimized together through response surface methodology based on a central composite design. The researchers fitted a second-order polynomial model over 20 experimental runs and assessed it using analysis of variance, lack-of-fit testing, coefficients of determination and residual diagnostics. The model was significant, with an F value of 39.38 and P below 0.0001, and explained 97.26% of the observed variation in ethanol concentration. Its adjusted R-squared value was 0.9479, the predicted R-squared was 0.8972 and the lack-of-fit test was not significant, with F = 0.52 and P = 0.7530. The experimental coefficient of variation was 5.76%, while the adequate-precision value of 15.959 exceeded the cited adequacy threshold. Residuals were approximately normally distributed, and the Box–Cox analysis did not indicate that response transformation was needed.

Within the tested domain, ethanol followed curved responses to all three concentrations rather than increasing indefinitely. Sucrose performed best near 4%, ammonium sulfate near 0.5%, and potassium chloride generally performed better toward the upper part of the concentration range examined by the model. None of the pairwise interaction terms was statistically significant: sucrose by ammonium sulfate had P = 0.6630, sucrose by potassium chloride P = 0.5066, and ammonium sulfate by potassium chloride P = 0.4171. The response surface therefore attributed the main pattern to individual and quadratic effects rather than detectable interactions between nutrient pairs. The fitted model identified 4.06% sucrose, 0.5% ammonium sulfate and 0.11 milligrams per millilitre potassium chloride as the optimum, predicting 2.42 grams of ethanol per 100 millilitres with a desirability value of 0.941.

Triplicate validation at that optimum produced 2.345 grams of ethanol per 100 millilitres, equal to 96.9% of the model prediction and within its reported 95% confidence interval of 2.33–2.51 grams per 100 millilitres. Using the extract’s initial total-sugar concentration of 10 grams per litre and the added sucrose, the researchers calculated an initial supplemented sugar concentration of 5.0 grams per 100 millilitres. With a theoretical factor of 0.511 grams of ethanol per gram of sugar, that input corresponded to 2.555 grams of ethanol per 100 millilitres, making the observed value 91.8% of the theoretical estimate. On a direct mass comparison, the ethanol represented 46.9% of the initial sugar mass. Neither figure directly measured sugar consumption, however, because residual sugars, biomass, carbon dioxide and other fermentation products were not quantified after fermentation.

The results do not establish industrial competitiveness. The study’s ethanol concentration of 23.45 grams per litre was higher than the 19.9 grams per litre reported for liquid-hot-water-pretreated bagasse in the paper’s comparison, but it was below values of 44.5 and 61.3 grams per litre reported for more intensive integrated and soda-pretreatment processes. The work was conducted at laboratory scale and did not include a techno-economic assessment, downstream nutrient treatment, scale-up or a complete carbon balance. The authors also acknowledge that model validation occurred only at the predicted optimum, without multi-point testing or calculation of mean absolute error and root mean square error. The experiment therefore provides laboratory evidence that nutritional optimization can improve fermentation of a low-severity bagasse extract, rather than proof of a commercially ready waste-to-ethanol process.

Overall, the experiments show that targeted nutrient management can overcome part of the nutritional limitation of minimally processed aqueous sugarcane bagasse extract. Sucrose supplied additional fermentable carbon, ammonium sulfate supplied nitrogen, and potassium chloride supplied a mineral component, with each supplement displaying a distinct concentration-dependent response. Optimizing the three together raised the experimentally measured ethanol concentration to 2.345 grams per 100 millilitres without adding chemical or enzymatic pretreatment to the extraction step. The study did not directly track sugar consumption, carbon distribution or economic feasibility, and it did not use high-performance liquid chromatography to distinguish individual sugars. Further work involving residual-sugar measurements, individual-sugar profiling, complete carbon accounting, multi-point model validation, larger-scale fermentation and techno-economic evaluation would be required to determine whether the strategy can translate into an efficient industrial process.

Subject of Research: Nutritional optimization of Saccharomyces cerevisiae fermentation using aqueous sugarcane bagasse extract for bioethanol production

Article Title: Nutritional optimization of aqueous sugarcane bagasse extract for enhanced bioethanol production by Saccharomyces cerevisiae MTCC 180

Article References: Ray, S., Mukherjee, A., & Ghosh, U. (2026). Nutritional optimization of aqueous sugarcane bagasse extract for enhanced bioethanol production by Saccharomyces cerevisiae MTCC 180. Frontiers in Industrial Microbiology, 4, Article 1971432. https://doi.org/10.3389/finmi.2026.1971432

Image Credits: AI Generated

DOI: 10.3389/finmi.2026.1971432

Keywords: sugarcane bagasse, bioethanol, Saccharomyces cerevisiae, nutritional optimization, response surface methodology, fermentation, sucrose, ammonium sulfate, potassium chloride, waste valorization, Nutritional, optimization

Conjoined twins arise from aberrant embryogenesis in a monozygotic, monochorionic pregnancy, in which the developing embryos fail to separate completely. They are extraordinarily rare, with an estimated incidence of one in 100,000 to 250,000 births, and roughly half of affected pregnancies end in stillbirth. The condition occurs more frequently in females, at a ratio of approximately three to one. Classification depends on the site of fusion: thoracopagus twins are joined at the chest, omphalopagus at the abdomen, ischiopagus at the pelvis, craniopagus at the head, and pygopagus twins at the sacrum or rump. Pygopagus twins account for only about 6 to 19 percent of all conjoined twin cases, making them one of the rarer varieties. In pygopagus fusion, the twins typically share portions of the gastrointestinal and genitourinary systems, and in a small minority of cases the neural elements are involved as well. Of the pygopagus separations reported in the medical literature, shared dura has been documented in 17 cases and shared spinal cord in only 10, underscoring just how unusual the anatomy in this new case truly was.

The twins in this report were discovered during a routine prenatal ultrasound at 20 weeks of gestation, allowing the mother and her obstetricians to plan carefully for the delivery. Her antenatal course remained otherwise uneventful, and the babies were born by preplanned lower segment cesarean section at a government medical hospital, with a combined birth weight of 3.6 kilograms. The infants were fused at the lower body in the sacral region by a soft tissue bridge measuring roughly 10 centimeters across the skin. They were referred to a tertiary medical college two days after birth, where they were designated Twin A and Twin B. Baseline investigations showed stable physiological parameters in both infants, and echocardiography confirmed normal cardiac anatomy and function in each, with no shunt anomalies and normal pulmonary artery pressures. Abdominal ultrasound detected no significant abnormalities, meaning the twins did not share vital visceral organs, a factor that substantially improved their surgical prognosis.

When a multidisciplinary board of pediatric surgeons, neurosurgeons, pediatricians, anesthesiologists, and a dedicated pediatric clinical nutritionist convened to evaluate the pair, they reached a critical conclusion: the infants were simply too small and too underweight to withstand the physiological trauma of a prolonged separation surgery. Moreover, the skin and subcutaneous tissue surrounding the conjoined pelvic junction were judged insufficient for tension-free primary closure. Rather than rushing to the operating room, the board opted for a delayed elective approach, instituting a structured nutritional rehabilitation program supervised by the clinical nutritionist. The twins received maternal breastfeeding supplemented with calorie-dense nutrition, with a target weight gain velocity of 20 to 30 grams per day per infant. Over the following months, their combined weight climbed to 8.9 kilograms, and biochemical markers confirmed that they had built sufficient physiological reserves to tolerate intraoperative blood loss, lengthy anesthesia, and the hypercatabolic stress of post-surgical healing.

The delay also served a second, equally important purpose: it allowed natural somatic growth to generate the redundant skin needed for reconstruction. The team had formally considered inserting mechanical tissue expanders, devices commonly used to stretch skin before complex closures. They ultimately rejected this option for three reasons: stringent institutional resource limitations, the heightened risks of expander erosion, hematoma, and catastrophic implant infection given the proximity to the diaper and perineal region, and the encouraging clinical evidence that spontaneous growth was producing sufficient cutaneous redundancy on its own. Surgeons serially assessed the pinch-laxity and dermal mobility of the lateral gluteal and flank skin relative to fixed skeletal landmarks, including the sacrococcygeal junction and the posterior superior iliac spines. Robust capillary refill times of under two seconds and the absence of scar tethering confirmed healthy microvascular perfusion, and by the time of surgery the natural tissue creep had generated enough lateral skin folds to permit primary local flap reconstruction without any synthetic prostheses.

Neuroimaging proved decisive in mapping the twins’ shared anatomy. A computed tomography scan with three-dimensional reconstruction at three months of age revealed that each twin had an independent, anatomically normal cervical, thoracic, and lumbar spine, with no osseous bridging and skeletal contact limited to the lower sacrococcygeal region. Magnetic resonance imaging of the pelvis then delivered the finding that defined the case: the sacrum was deficient in both infants, and the distal spinal cords and dural sacs converged and fused near the sacrococcygeal level within the soft tissue bridge. The thoracic and abdominal visceral compartments remained entirely separate. This combination of shared spinal cord and shared dura is exceptionally rare in pygopagus twins and dramatically raises the stakes of separation, since any misjudgment during cord division risks permanent neurological injury to one or both children. After reviewing the imaging, the surgical board scheduled the operation, though it was postponed once more when Twin A developed pneumonia, ultimately taking place six months after birth, which coincidentally aligned with the internationally recommended window of four to twelve months for planned elective separation.

The operation itself showcased how surgical precision can substitute for technology. Because advanced intraoperative neurophysiological monitoring, including somatosensory evoked potentials, motor evoked potentials, and electromyographic nerve root stimulation, was unavailable, neural preservation depended entirely on high-magnification operating microscopy and anatomical landmarks. The infants were positioned in a synchronized lateral decubitus position, and the team designed a modified curvilinear zigzag, interlocking S-pattern incision over the posterior bridge, a geometry chosen to distribute skin tension evenly, prevent straight-line scar contracture over the sacrum, and optimize flap interdigitation for each twin. Subcutaneous flaps were elevated down to the paraspinal fascia, and the sacrococcygeal junction served as the principal anchor for the exposure. Under high-power magnification, the fused thecal envelope was incised longitudinally along the midline raphe, opening the common dural chamber.

Inside the shared thecal sac, the surgeons traced each nerve root systematically, both proximally toward its origin on the cord and distally toward its corresponding neural foramen, confirming bilaterally and visually that every root belonged unequivocally to its respective infant before any division. With gentle blunt micro-dissection and continuous saline irrigation, the conjoined lower cord elements were separated without sacrificing functioning neural tissue from either twin, and the thecal sac was partitioned into two distinct envelopes. Each baby was then moved to a separate operating table, where the team repaired the dura under the microscope using 6-0 polypropylene sutures in a watertight fashion, reinforced the closure with a fascial layer, and confirmed the absence of cerebrospinal fluid leakage with a Valsalva maneuver before closing the wounds in layers. Cerebrospinal fluid leakage is a historically frequent and dangerous complication in pygopagus separations involving dural sharing, making this watertight closure one of the operation’s most consequential technical victories.

The postoperative course was largely uneventful. Apart from a bout of pneumonia in Twin B on the third day, which was treated successfully, neither infant developed surgical site infections, wound dehiscence, flap necrosis, or cerebrospinal fluid leaks. Detailed neurological examinations before discharge revealed active, symmetric, spontaneous movements of both lower extremities in each infant, normal muscle tone across the hip flexors, quadriceps, and gastrocnemius muscles, and brisk, bilaterally equal deep tendon reflexes. Sensory withdrawal responses were intact across all lumbar and sacral dermatomes from L1 to S3, and both twins displayed robust anal wink reflexes, confirming preservation of the S2 to S4 sacral autonomic and pudendal pathways that govern bowel and bladder control. Both infants demonstrated normal spontaneous fecal evacuation and independent voluntary voiding. They were released on the twelfth postoperative day with basic vitamin supplements and are now reportedly healthy and living independently.

The outcome carries weight well beyond this single hospital. Survival rates for conjoined twins after separation range from roughly 16.7 to 50 percent depending on the type of operation and whether it is elective or emergency, and mortality climbs sharply when neurological structures are shared, since it is exceptionally difficult for both twins to survive the division of a joined spinal cord. The authors of the report are candid about the limitations of their approach: nutritional and skin assessments relied on clinical expertise and biochemical parameters rather than validated scoring tools or perfusion devices, no real-time electrophysiological feedback was available during cord division, and follow-up assessments were clinical rather than urodynamic or electrodiagnostic. Even so, the case demonstrates that three surgical strategies, fixed skeletal anchoring, stepwise magnified micro-dissection, and individual rootlet verification before dural division, can substitute meaningfully for expensive neuromonitoring. For surgical teams across the developing world, where conjoined twin separations are often deemed impossible without technology-rich environments, this successful delayed elective separation offers both a practical roadmap and a compelling proof of concept.

Subject of Research: Delayed elective surgical separation of pygopagus conjoined twins with shared spinal cord and dura

Article Title: Successful Delayed Elective Separation of Pygopagus Conjoined Twins With Shared Spinal Cord and Dura in a Resource‐Limited Setting: A Case Report

Article References: Wahid, Z. U. M., Chowdhury, S. I., Islam, N., & Mifty, S. K. (2026). Successful Delayed Elective Separation of Pygopagus Conjoined Twins With Shared Spinal Cord and Dura in a Resource‐Limited Setting: A Case Report. Clinical Case Reports, 14(10), Article e73657. https://doi.org/10.1002/ccr3.73657

Image Credits: AI Generated

DOI: 10.1002/ccr3.73657

Keywords: conjoined twins, pygopagus, spinal cord, separation surgery, neurosurgery, pediatric surgery, microsurgery, resource-limited settings, dural repair, nutritional optimization, case report, tissue expansion