Comparative Study of Biogas Production from Jackfruit Waste, Banana Peels, and Pineapple Peels Co-Digested with Cow Dung

Only 42% of Uganda’s population has access to electricity. The population continues to use firewood and charcoal as a source of energy, which leads to depletion of forests thus to climate change. The purpose of this study was to assess the potential of biogas production from jackfruit waste, banana peels, and pineapple peels when co-digested with cow dung as an alternative energy source. Substrates for each waste were co-digested with varying proportions (0%, 25%, and 50%) of cow dung using laboratory-scale 250 mL anaerobic digestors. The total biogas generation for jackfruit waste, banana peels, and pineapple peels after 30 days of anaerobic digestion was 82.3, 189, and 262 mL, respectively. When jack fruit waste, pineapple peels and banana peels were co-digested with 25% cow dung, the total amount of biogas produced increased by a factor of two and three, respectively. However, 50% of cow dung only significantly (p ≤ 0.05) improved for jack fruit waste by two folds. Therefore, the results indicated that jackfruit waste, banana and pineapple peels can be used for biogas production to augment energy supply. .

Determination of the Antioxidant Potentials of Two Different Varieties of Banana Peels in Two Different Solvents

Fruit wastes which are perishable pose a big problem to pollution monitoring agencies;however these problems can be reduced by utilizing the high value compounds present in the food waste. Banana peels contain a reasonable number of antioxidant compounds such as gallocatechin and dopamine. This paper investigates the anti-oxidant potential of two different varieties of Banana peels (Dwarf cavandish and Musa omini). The peels were extracted with two different solvents (Methanol and Ethanol) using the soxhlet extractor. The results show that ethanolic extracts have higher phenolics and flavonoid contents (336.83 - 383.83 mgGAE/100g, 242.83 - 252.82 mgRutin/100g) compared to the methanolic extracts of the same banana varieties (299.42 - 344 mgGAE/100g, 240.77 - 241.23 mgRutin/100g). However methanolic extracts exhibit higher DPPH Antioxidants Activity (30.82% - 51.66%) compared to ethanolic extracts (25.44% - 30.27%). This implies that antioxidative compounds other than phenolics and flavonoids were also involved in inhibiting the DPPH Radicals. It was also observed that at any concentration between 0.5 - 2.5 mg, ethanol extracts of both dwarf cavandish and musa omini had higher reducing power than the other two varieties.

Banana Peel for Acetylsalicylic Acid Retention

A method for adsorption involving banana peel (BP) was studied to remove the pollutant acetylsalicylic acid (ASA) in aqueous medium. The results show that bioadsorbent has satisfactory maximum adsorption capacity (2.29 mg/g) for removing this analgesic and anti-inflammatory drug in aqueous solution (pH 7.0) using the Langmuir mathematical model. The tested concentrations of this pollutant were higher than the levels commonly found in the aquatic environment. This and other results suggest the BP as an alternative to ASA removal in water contaminated with pharmaceuticals pollutants.

Heavy metals adsorption by banana peels micro-powder: Equilibrium modeling by non-linear models

In this study the copper and lead adsorption efficiency onto banana peels powder was investigated. The agroindustrial waste recovery represents one of the Circular Economy pillars. In the view of the synthesis of an environmentally friendly adsorbent material, the powder was used without any preliminary chemical or thermal activation, but only after simple washing, drying and grinding. The bio-adsorbent was characterized by the FTIR technique and tested in batch mode on synthetic aqueous solutions containing Pb and Cu in the range 10–90 mg·L^(-1). A selection of two(Langmuir, Freundlich) and three(Sips, Redlich–Peterson, Koble–Corrigan) parameter isotherm models was chosen to fit adsorption equilibrium data by non-linear regression procedure. The best fit isotherm model was selected relying on the error function with the lowest average percentage error(APE) value, among those characterized by the highest R^2 values. As expected, the three-parameter models are found to better represent both metals bio-adsorption, with APE and R^2 values always lower and higher, respectively, than the corresponding values obtained for the two-parameter models.

Preparation of Hierarchically Interconnected Porous Banana Peel Activated Carbon for Methylene Blue Adsorption

Hierarchically interconnected porous activated carbon have high specific surface areas, large numbers of dye adsorption sites, and interconnected pores for dye molecule diffusion and transportation. We prepared hierarchically interconnected porous banana peel activated carbons(BPACs) via a green method involving hydrothermal pretreatment and KOH activation, and systematically tested its methylene blue(MB) adsorption capacity. SEM showed that the BPACs had an interconnected porous structure and high-porosity surface. The Brunauer-Emmett-Teller surface area was 601.21 m^2/g, the adsorption average pore diameter was 2.11 nm, and the total pore volume was 0.32 cm^3/g. The MB adsorption capacity increased with increasing temperature, initial MB concentration, and pH value; it decreased with increasing adsorbent dosage. The adsorption isotherms and kinetic results for MB adsorption on BPACs were best described by the Langmuir adsorption and pseudo-second-order kinetic models, respectively. BPACs have a well-developed hierarchically interconnected porous structure, which increase the MB adsorption capacity and removal efficiency. Systematic MB adsorption tests show that BPAC is a highly efficient and easily available adsorbent.

Enhanced Biogas Production from the Anaerobic Batch Treatment of Banana Peels

Waste disposal management and the energy crisis are important challenges facing most countries.The fruit-processing industry generates daily several tons of wastes,of which the major share comes from banana farms.Anaerobic digestion(AD)technology has been applied to the treatment of wastewater,animal slurry,food waste,and agricultural residues,with the primary goals of energy production and waste elimination.This study examines the effect of organic loading(OL)and cow manure(CM)addition on AD performance when treating banana peel waste(BPW).The maximum daily biogas production rates of banana peels(BPs)with a CM content of 10%,20%,and 30%at 18 and 22 g of volatile solids(gvs)per liter were 50.20,48.66,and 62.78 mL (gvs.d)^-1 and 40.49,29.57,and 46.54 mL (gvs.d)^-1,respectively.However,the daily biogas yield showed no clear interdependence with OL or CM content.In addition,a kinetic analysis using first-order and cone models showed that the kinetic parameters can be influenced by the process parameters.

Well-dispersive K2O-KCl alkaline catalyst derived from waste banana peel for biodiesel synthesis

In this work, a novel alkaline catalyst was synthesized by an economical and effective method of roasting waste banana peel. From XRD, FTIR, SEM, EDS, TGA and CO2-TPD characterization, it was proved that the calcined banana peel catalyst showed the strong alkalinity and well dispersity in microstructure, and K2O-KCl as the main active contents. The calcined banana peel catalyst showed better catalytic performance than the catalysts by physical mixing of K2O and KCl, which was due to good dispersibility of K2O-KCl formed during decomposing of carbon fiber by calcination of banana peel. Furthermore, the calcined banana peel catalyst also performed well in both water-resistant ability and recyclability, indicating their potential for biodiesel production from an efficient, robust, and low-cost catalyst.

Banana Peel Carbon that Containing Functional Groups Applied to the Selective Adsorption of Au(III) from Waste Printed Circuit Boards

This paper reports a kind of banana peel carbon (BPC) containing -OH, -NH2 functional groups which prepared through controlling carbonization temperature and its application on the selective adsorption of gold from waste printed circuit boards (PCBs). The adsorption of BPC for Au(III) reached equilibrium in 30 min and the adsorption of Au(III) was favorable at pH 2.5. Meanwhile, the adsorption isotherm showed the maximum adsorption capacity of 801.7 mg/g for Au(III). The results displayed that BPC had a strong selectivity for Au(III) and a negligible affinity to base metal ions, such as Cu(II), Ni(II), Fe(III) and Pb(II). The BPC adsorbent, which absorbed gold, can be recovered completely by HCl-thiourea solution.

Probing nutritional and functional properties of salted noodles supplemented with ripen Banana peel powder

Banana peel is appreciated for higher dietary fiber, phenolics, flavonoid contents, and minerals (particularly iron, calcium, and potassium), despite being a waste product. After drying, it can be processed into powder/flour to be combined with wheat flour (WF) for development of value-added products. In this study, we substituted WF with banana peel powder (BPP) at supplementation rates of 5, 10, and 15%, and evaluated their suitability to develop salted noodles. The results showed that the composite flour with 15% BPP had significantly higher protein, ash, and crude fiber content as compared to control. Higher antioxidant capacity was observed in composite flour noodles: total phenolics content (TPC), total flavonoid content (TFC), ferric reducing power (FRAP) and DPPH reducing power were increased up to 278, 260, 143 and 13 percent respectively in the noodles containing 15% BPP as compared to control (100% WF). On the other hand, values for viscosity decreased up to 22% with addition of BPP in WF. Furthermore, water absorption capacity and cooking losses were increased up to 15 and 13 percent respectively with 15% BPP incorporation in WF. Results for sensory evaluation demonstrated that noodles with 10% BPP scored highest for sensory profile.

Antioxidant Potential of Peel Extracts of Banana Varieties (<i>Musa sapientum</i>)

The study has been aimed to evaluate and compare phytochemical content and the antioxidant activity in peel extracts of nine local varieties of banana, i.e. Musa sapientum species. Ethanolic extract of peels of these varieties were subjected to in vitro free radical scavenging assays like DPPH, ABTS and lipid peroxidation inhibition assay. Total antioxidant capacity assay to confirm the antioxidant potential and phytochemical content such as total phenols, flavonoids were also determined. The results obtained were analyzed statistically by ANOVA and DMRT analysis. The peel ex- tracts of all the nine varieties of banana exhibited significant antioxidant and phytochemical activities with Musa spp – Blueggoe (Monthan) - AAB and Musa spp – Rasthali – AAB showing highest free radical scavenging activity and Musa spp – Karpooravalli – ABB, Musa spp – Rasthali – AAB, Musa spp - Ney Poovan (Kadali) – AB and Musa spp – Mysore (Poovan) – AAB having highest phytochemical content. The study suggests that peel extracts of these banana varieties could be useful to combat free radical mediated diseases.

香蕉果酒带皮发酵对其品质和挥发性香气成分的影响

为了探究香蕉皮对香蕉果酒品质和风味的影响,该研究对带皮香蕉果酒和去皮香蕉果酒发酵过程中糖度、酒精度、总酸和多酚等理化指标进行测定,同时利用气相色谱-质谱联用技术测定两种果酒中挥发性香气物质,结果显示带皮香蕉果酒的酒精度为10.5%vol,低于去皮香蕉果酒的12.3%vol,但是发酵结束后带皮香蕉果酒中总酸(4.03 g/L)和感官评分(87.62),要显著优于去皮香蕉果酒。此外,带皮香蕉果酒及其蒸馏酒中甲醇含量分别为120.20 mg/L和372.30 mg/L,远低于对应国家限量标准。挥发性风味物质分析结果显示香蕉酒中主要的风味物质为酯类和醇类,带皮香蕉果酒风味物质种类比去皮香蕉果酒更为丰富,其中乙酸乙酯(>8.10 mg/L)和3-甲基-1-丁醇(>15.78 mg/L)是香蕉果酒中主要的挥发性风味物质。因此香蕉皮的添加可以改善果酒品质和风味且不会显著提高果酒中甲醇的含量,但是对出酒率有一定的影响,该研究为实现食品原料的整体化综合利用、减少食品加工废弃物的生成拓宽了思路,同时也为开发高品质香蕉酒提供了参考。

Lead removal from aqueous medium using fruit peels and polyaniline composites in aqueous and non-aqueous solvents in the presence of polyethylene glycol

In the present study,composites of Polyaniline and some fruit peels were synthesized in various conditions and used for lead removal from aqueous solutions.Adsorption tests were conducted in batch mode using the most efficient adsorbent,and the effects of medium pH,initial lead concentration,contact time,adsorbent dosage,and adsorption isotherms were investigated.The results showed that all composites were more efficient in lead removal compared to the fruit peels alone.The highest removal percentage was related to the composite of banana peel and Polyaniline that synthesized in the aqueous solution in the presence of 2 g·L^(-1) Poly ethylene glycol.This composite showed 95.96%lead adsorption at pH=6,the contact time of 90 min,the initial lead concentration of 25 mg·L^(-1),and an adsorbent concentration of 8 g·L^(-1).Adsorption isotherm study showed that adsorption of lead by synthesized composite could be fitted by both Langmuir and Freundlich models,but the Langmuir model was more fitted than Freundlich.Besides,some characteristics of the composites,such as chemical composition(XRD analysis),structure,and morphology(SEM analysis)and functional groups(FTIR analysis),were studied.

Adsorption Isotherm Study of Activated Fruit Peels for Copper Removal

Heavy metal polluted water threatens the integrity of ecosystem.The use of agricultural waste as adsorbent becomes popular due to its biodegradability and availability.However,limited research works has been done to process agricultural waste for heavy metal adsorption purpose.The objective of this study is to propose a new approach to treat banana peel using ZnCl_(2) prior to alkali and acid treatment and explore the potential of dragon fruit peels as the adsorbent for Cu^(2+)adsorption.Seven adsorption isotherm was adopted to identify the adsorption mechanism and four statistical parameters were calculated for model verification purpose.The experiment was conducted by dispersing ZnCl_(2) treated and untreated adsorbents into Cu^(2+) solution.Results showed that ZnCl_(2) treated adsorbents performed better in terms of Cu^(2+) removal compared with untreated adsorbents due to higher surface area for Cu^(2+) adsorption.The treated banana peel(Act.-B)performed approximately 30%better than the treated dragon fruit peel(Act.-D)due to the presence of hydroxyl and carboxyl groups.The equilibrium adsorptive capacity of Act.-B was 1872.8 mg Cu^(2+)/g and the experimental data fitted Freundlich isotherm well with R^(2)=0.9978,0.0161 of residual sum of error(SSE),0.0068 of χ^(2),and 0.0567 of root mean square error(RMSE)values.This suggests non⁃linear adsorption and multilayer adsorption on heterogenous surfaces.Thus,it is recommended to further improve the surface properties of Act.-B by steam pyrolysis and surface modification.

Formulation and evaluation of semisolid jelly produced by Musa acuminata Colla(AAA Group) peels

Objective:To study the jelly formulation produced by Musa acuminata Colla(AAA Group) peels and evaluate its antioxidant properties which are related to the product quality.Methods:The formulations of peel jelly were established under two-level full factorial designs within two blocks and one center point.Regarding response optimizer,the amount of sugar and citric acid was obtained;hence,the peel jellies were produced.The evaluation of antioxidant properties was conducted by using total phenolic content(TPC)assay and 1,1 diphenyl-2-picrylhydrazyl(DPPH) free radical assay.Results:The TPC of peel powder varied from 91.8 to 602.26 mg gallic acid equivalents/100 g dry weight,and 5%-7% peel jellies had phenolic content ranging from 29.38 to 48.31 mg gallic acid equivalents/100 g dry weight.The results of DPPH test indicated that at 10 mg/mL,the peel powder showed 89% DPPH inhibition,while 7% peel jelly prominently exhibited 84% DPPH inhibition.The correlation between DPPH IC50 value and TPC of peel powder as well as peel jelly was quite reasonably high with correlation coefficient ranging from 0.843 7 to 0.995.Conclusions:TPC can be used as an indicator in assessing the antioxidant activity of fruits and vegetables.The present investigation reveals that TPC is mainly responsible for DPPH free radical scavenging capacity.

低温对2个香蕉品种采后生理和后熟期品质的影响

【目的】明确低温对不同香蕉品种采后生理和后熟期品质的影响,为改善越冬挂果香蕉果实品质及提升商品价值提供参考依据。【方法】以饱满度70%的宝岛蕉和桂蕉6号香蕉果实为试验材料,分别经低温[(6±0.5)℃]处理48 h(T1、T2),以常温[(22.0±0.5)℃]处理为对照(CK1、CK2),在相同催熟条件下,比较分析低温处理对2个香蕉品种后熟过程中果皮外观色泽、果皮多酚氧化酶(PPO)和过氧化物酶(POD)活性、果实内在品质及细胞膜透性的影响。【结果】后熟第3、5、7天,T1处理果皮亮度(L值)均显著高于T2处理(P<0.05,下同),分别高19.7%、22.6%和67.7%,并且T1和T2处理果皮L值显著低于CK1和CK2。后熟第3天,T2处理果皮色度(H值)比T1处理显著低9.4%,此时T2处理果皮开始褪绿,2种处理条件下宝岛蕉(T1、CK1)果皮转色均较桂蕉6号(T2、CK2)晚2 d左右。后熟过程中,T1和T2处理果皮PPO和POD活性均显著高于CK1和CK2;后熟第3和5天,T2处理果皮POD活性分别显著高于T1处理22.6%和13.1%。后熟第3天,T1处理果肉硬度比T2处理显著高30.1%;后熟第1和第3天,CK1果肉硬度比CK2分别显著高37.4%和30.0%,T2处理和CK2果肉硬度比T1处理和CK1下降快;随着成熟进程的推移,各处理香蕉果肉可溶性固形物含量呈上升趋势,淀粉和维生素C含量呈下降趋势,T1和T2处理可溶性固形物含量增长速度及淀粉和维生素C含量下降速度均比CK1和CK2显著减慢,T1处理与T2处理间差异不显著(P>0.05)。在后熟进程中,T2处理细胞膜透性显著高于T1处理、CK1和CK2。【结论】低温对桂蕉6号果皮颜色褐化程度及细胞膜透性增加的影响比宝岛蕉更显著。在2种处理条件下,宝岛蕉果皮褪绿转黄、果肉硬度下降均比桂蕉6号晚2 d左右,宝岛蕉贮运品质更佳。低温对2个香蕉品种果实可溶性固形物、淀粉和维生素C含量影响差异不显著。

香蕉皮提取物通过调节肠道菌群和肠神经递质水平提高便秘模型小鼠肠动力

探究香蕉皮提取物对便秘小鼠肠动力的干预作用。本研究采用混合抗生素溶液构建便秘小鼠模型。用香蕉皮提取物溶液对便秘小鼠进行干预,并测定其对便秘小鼠的肠道菌群、肠神经递质水平和肠动力的影响。结果表明,高浓度香蕉皮提取物组小鼠的粪便含水量增加了137.5%、小肠推进率增加了3.4倍、首粒黑便排出时长减少了73.7%(P<0.05),且基本恢复到空白组小鼠水平。便秘模型小鼠菌群紊乱,部分有益菌缺失,经低浓度香蕉皮提取物干预后,属水平上Trabulsiella(特布尔西菌属)和Unclassified-f-Enterobacteriaceae的相对丰度增加了6倍,肠道Bacteroides(拟杆菌属)的相对丰度减少了94.4%。在神经递质中,低浓度香蕉皮提取物组小鼠的去甲肾上腺素、多巴胺、γ-氨基丁酸、乙酰胆碱的浓度显著增加了6.1%、17.6%、63.7%、52.6%。以上结果表明,香蕉皮提取物可调节肠道菌群和肠神经递质水平提高便秘小鼠肠动力。

香蕉皮粉末对黑腹果蝇的引诱活性及挥发物化学成分分析

黑腹果蝇(Drosophila melanogaster)是危害杨梅的主要果蝇种类,而通过引诱剂监测并诱杀该害虫是一项绿色且环保的害虫控制技术。本文利用固相微萃取技术(SPME)连续5 d分别收集成熟香蕉皮粉末逐日发酵的化学物质,并采用气相色谱质谱(GC-MS)分析其化学成分;进一步通过室内行为选择测试和室外果蝇种群动态监测探讨香蕉皮粉末对黑腹果蝇的引诱效果。结果表明,第1天和第2天香蕉皮粉末中芳香成分均以3-甲基丁酸丁酯为主要成分,含量分别达到56.79%和40.25%,并与第3、4、5天化学成分以及含量均存在明显差异。而分别发酵1、3、5天的香蕉皮粉末对黑腹果蝇的行为选择表明,第1天的香蕉皮粉末引诱活性最高,对雌、雄虫的引诱率分别达到62.50%、60.00%,而第3天和第5天的香蕉皮粉末无引诱活性。而野外动态监测进一步表明,香蕉皮粉末中存在引诱果蝇的芳香成分。此外,室内行为选择也表明了3-甲基丁酸丁酯较好的引诱活性,当质量浓度为1000μg·mL^(-1)时,对雌、雄成虫的引诱率分别高达71.25%、66.25%。因此,推测香蕉皮粉末中的3-甲基丁酸丁酯为主要的引诱活性物质,在开发黑腹果蝇引诱剂方面具有潜在用途。

香蕉皮膳食纤维的酶法提取优化及理化性质分析

以中性蛋白酶与α-淀粉酶共同作用提取香蕉皮中的膳食纤维,在单因素试验的基础上通过正交试验优化提取工艺。结果表明:最佳工艺条件为料液比1∶22(g/mL)、α-淀粉酶添加量0.5 g、中性蛋白酶添加量0.15 g、α-淀粉酶水浴时间60 min,在此条件下可溶性膳食纤维得率为16.35%±0.34%。不溶性膳食纤维与可溶性膳食纤维均有一定的持水性、持油性、吸水膨胀力、葡萄糖吸附能力及胆固醇吸附能力。

TiO_(2)-SiO_(2)改性香蕉皮生物炭对水中二氯喹啉酸吸附性能研究

为了寻找有效去除污水中二氯喹啉酸(QNC)的方法,以农业废弃物香蕉皮为原料,磷酸、TiO_(2)和SiO_(2)为活化剂,制备了TiO_(2)-SiO_(2)改性香蕉皮生物炭(Ti-Si-BC)。采用扫描电镜(SEM)、X射线衍射(XRD)、红外光谱(FTIR)、比表面积法(BET)和元素分析(EDS)等手段对改性前后生物炭的物理化学性质进行表征,研究了Ti-Si-BC对QNC的吸附机理以及接触时间、初始浓度、温度和吸附剂用量等因素对吸附效果的影响。结果表明:磷酸、TiO_(2)和SiO_(2)的协同改性显著提高了生物炭的比表面积并增加了吸附点位。在QNC初始浓度为60 mg·L^(-1)时,Ti-Si-BC对QNC的吸附率是天然香蕉皮生物炭(BC)的2.5倍。Ti-Si-BC对QNC的吸附动力学过程更符合准二级动力学模型,说明吸附包括表面的物理吸附和内部的化学扩散。等温吸附过程更符合Freundlich模型,说明吸附为非均相多层吸附。热力学结果表明该吸附为吸热的自发反应。Ti-Si-BC对QNC吸附的机理主要包括孔隙填充、静电和氢键等作用,其吸附效果较BC明显提高,具有良好的应用潜力。